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Carriera e attività
Shahla Lahiji () ha conseguito una laurea in sociologia presso la Open University di Londra e nel 1983 fondò la casa editrice Roshangaran, diventando così la prima editrice donna in Iran. Nel 2006 la Roshangaran pubblicò più di 200 articoli che o erano stati redatti da scrittrici o riguardavano diverse questioni femminili. Nel 2001  la casa editrice ricevette il premio PEN International negli Stati Uniti e il premio Pandora nel Regno Unito.

Lahiji fu una dei diciannove scrittori e intellettuali accusati penalmente per aver partecipato ad una conferenza accademica e culturale finanziata dalla Fondazione Heinrich Böll a Berlino, tenutasi dal 7 al 9 aprile 2000, durante la quale furono dibattute in pubblico le riforme politiche e sociali dell'Iran. Prima di essere rilasciata su cauzione nel giugno 2000, fu trattenuta nella prigione di Evin, dove per diversi mesi gli interrogatori si svolsero senza la presenza di avvocati. Sei dei diciannove intellettuali accusati per aver partecipato alla conferenza di Berlino furono assolti e undici condannati a pene detentive, la cui durata variava dai quattro ai quattordici anni. Tuttavia molti di loro, come il noto ecclesiastico e scrittore Hasan Yousefi Eshkevari, vennero successivamente rilasciati. A seguito della conferenza, Shahla Lahiji fu condannata a tre anni e sei mesi di carcere per aver ostacolato la sicurezza nazionale e ad altri sei mesi per aver trasmesso informazioni contro la Repubblica islamica esponendo i pericoli che devono affrontare gli scrittori iraniani. La condanna fu infine ridotta a sei mesi.

Libri

 The Quest for Identity : The Image of Iranian Women in Prehistory and History, scritto in collaborazione con Mehrangiz Kar, 1992
 Iran Awakening: One Woman's Journey to Reclaim Her Life and Country, scritto in collaborazione con Azadeh Moaveni, 2007
 Quello che mi spetta di Parinoush Saniee, (fu la coautrice), 2010 (pubblicato per la prima volta nel 2002)

Altre pubblicazioni

 Lahiji, Shahla  Scarecrow Press, Inc 2013.

Onori e premi

 2001: PEN/Barbara Goldsmith Freedom to Write Award
 2006: IPA Publishers' Freedom Prize

21 settembre 2006, Ginevra (Svizzera) e Göteborg (Svezia): durante la cerimonia di apertura della Fiera del libro di Göteborg all'editrice iraniana Shahla Lahiji verrà consegnato il premio IPA Publishers' Freedom Prize, al fine di onorare la sua straordinaria promozione e difesa della libertà di espressione, come anche la sua libertà di stampa in Iran e nel mondo. Tra i validi candidati nominati dai membri dell'International Publishers' Association (IPA), da editori indipendenti e da organizzazioni per i diritti umani, il consiglio di amministrazione dell'IPA sceglie come vincitrice Shahla Lahiji.

Voci correlate
 Shirin Ebadi
 Shahla Sherkat

Note

Collegamenti esterni
 Hajir Palaschi: "Interview with Shahla Lahiji on Women's Presence in the Labor Market: No Vocation Must Be Prohibited for Women"
 Shahla Lahiji, anvari.org
 Interview with Shahla Lahiji on Women's Presence in the Labor Market: No Vocation Must Be Prohibited for Women

Scrittori iraniani
Persone viventi
Nati nel 1942

redpajama_set_name: RedPajamaWikipedia


Each dbx environment variable is also accessible as a ksh variable. The name of the ksh variable is derived from the dbx environment variable by prefixing it with DBX_. For example dbxenv stack_verbose and echo $DBX_stack_verbose yield the same output. You can assign the value of the variable directly or with the dbxenv command.


All-weather boots that take on anything. The most durable platform on the market combines with Ariat's secure, comfortable ATS stability system. This oil- and slip-resisting sole provides extreme heat (tested to 750°F/400°C) and abrasion resistance. Waterproof Pro construction blocks out the rain, snow, and mud. Premium full-grain leather upper, Goodyear Welt construction, ergonomic support and cushioning, this heavy-duty boot delivers.


OUTSIDE The gardens are matures and include - to the front of the property and accessed from the front an original Solarium: brick built with extensive glazing and glazed double doors, woodblock floor, the room measuring about 12' x 11' with bay window seat to rear, leaded-light cupola/domed skylight. Separate and beyond this is a Garage: about 32' x 12' with pitched tiled roof over a brick construction with triple sliding doors, 2 inspection pits, power and electricity connected. To one side beyond a wrought iron entrance gate allows access to rear garden, part-walled. Delightful rear gardens with paved patio stepped down to 100ft rear garden in the main laid to grass interspersed with flower beds, mature shrubs, and fruit trees, mature hardwood trees, to rear a small hidden garden. 3 exterior brick store sheds.
Disclaimer - Property reference 101587013326. The information displayed about this property comprises a property advertisement. Rightmove.co.uk makes no warranty as to the accuracy or completeness of the advertisement or any linked or associated information, and Rightmove has no control over the content. This property advertisement does not constitute property particulars. The information is provided and maintained by Exquisite Home, Suffolk. Please contact the selling agent or developer directly to obtain any information which may be available under the terms of The Energy Performance of Buildings (Certificates and Inspections) (England and Wales) Regulations 2007 or the Home Report if in relation to a residential property in Scotland.


Counselling and psychotherapy provide you with a safe and confidential environment where you can talk through things that are concerning you. Together, we would work on understanding your emotions and making better sense of your world.
Our emotions are very important and we need to invest in them from time to time. This can be prove difficult when we live in today's fast pace society. We can sometimes feel like there is no time to listen to our emotions and, as a result we can neglect our emotional selves. So, where do we turn when we feel that life is getting too much, or we cannot make sense of our thoughts and feelings?
Healthy Vue Therapy, based not far from Fareham offers you the opportunity to take some time to focus on you and support you in rediscovering what's important. Make a positive change today and begin the journey to a healthier, happier life.
This is not an exhaustive list and I recognise that you may feel that your issue may not fall into any of these categories so I would encourage you to get in touch and discuss any questions you may have regarding the suitability of my service using the online form.


One of my first works of art and my very first cheeky Friesian cow.. She still makes me smile! One of my best selling pieces. Stock running low!!
This piece is a reproduction of an original textile artwork. The 'Giclee' process of printing ensures the quality is of the highest standard and colours will not fade, even in sunlight.
All prints are of the highest possible fine art quality. 'Giclee' is the term used to describe a fine art digital printing process which combines high quality ink with superior archival quality paper so your print will look as good in a hundred years as it did the day you purchased it!
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These limited edition fine art prints are mounted with a 2" antique white mount and ready to frame.
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Prints are supplied rolled in an art postal tube without a mount.
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Beautifull home 3 bedroom 2 and 1/2 baths in a gated community! Sparkling community pool, gorgeous clubhouse and more! With granite counter tops in kitchen and baths, ceiling fans throughout, cozy fireplace in living area and all bedrooms are located upstairs!This listing is submitted subject to errors,omissions or changes without notice.


Submitted by Mathias on Mon, 2010-11-29 14:04.
Paul Hubweber started with playing the drums at the age of 12. After a period of playing guitar and bass he started the trombone. He toured through Europe, jamming with several musicians all over Italy, France, the Netherlands. Coming back he settled down in Moers and began working within the organization of the Moers Festival 1973 - 77 and the Globe Unity Orchestra Workshop in 76. Also he mastered the Braxton Solo and the Christmann-Schoenenberg records on Ring music.
Hubweber's 1st solo record and lots of collages where produced at his own label msc between 76 - 82, and the cooperation with musicians like Claus van Bebber, Martin Theurer, Ulrich Phillipp and others began. This fits into different group activities like ARTE Festivals Kleve, Witten Easter Festivals, "der Gute ton", Moers, Wuppertal, Cologne, Aachen (together with Paul Lytton).
In Wiesbaden Hubweber had lots of sessions, concerts and several contributions to the HumaNoise Congress, and since 1984 gigs with John Butcher, Alfred Zimmerlin, Dorothea Schürch. He met lots of interesting international musicians there.
In the late 80's Hubweber founded another musicians' cooperation in Cologne (AIM) together with his college Georg Wissel, with whom he had some different ensembles like BULL'S EYE ENSEMBLE, KOLLEGU PISCHU (i.e. Live Music to the silent film "The Adventures of Mr.West in the Land of Bolschewijki", Lew Kuleschow, UdSSR 1924, with Wissel and Hans Kanty(† 2005).
The 90's started with a new version of the van Bebber-Hubweber Duo (since 1976) under the name of Vinyl & Blech. The trombone is electrified by numerous effects like tube screamer, echolette, harmonizer etc. The sounds of Claus van Bebbers' vinyl and the trombone often fuse and getting an industrial touch (technos love it!).
He met dancer Britta Lieberknecht and they started their continuing cooperation in four different projects. These choreographies do not have the main focus on improvisation but on the relationship between sound, movement and light. Improvisations plus Pina Bausch- and Kowald dancer Jean Sasportes since 2008.
Second main contact with Peter Kowald (the first was in the early Moers days) was the introduction of PAPAJO, "one of the most important ensembles on the contemporary market" (Alois Fischer). Peter and Paul had a few sessions at the 99's HumaNoise Congress and after this the SURPRISE UNIT with Fine Kwiatkowski and Michael Vorfeld. In 2000 they toured in trio with drummer/shouter Klaus Wallmeier. But Hubweber wanted to have two of his favourite musicians, Kowald and Lovens, together in one group and so they played some gigs as a trio. Because of Kowald became sick, John Edwards replaces Peter. This was a most elegant solution, because: "Balance in perfection ... nearly brilliant ... ensemble playing on a nearly perfect level ... a unity of mutual timing and presence resulting in music of high intensity..." as the Neue Westfälische/Bielefeld wrote . PAPAJO (PAul + PAul + JOhn) had the first CD at Martin Davidson's Emanem and will edit the 2nd CD September 2007 by the NY label Cadence. 2 records on Emanem and Cadence.
One of the important bullets in electro-acoustic music is the one with Uli Böttcher called SCHNACK. Enthusiastically modulated presets and Live-Sampling/Sound Processing seduce the trombone. ("sharp - i really like it !" Michel Waisvisz). They did more then 50 gigs in two years and they often cooperate with Michel Waisvisz. Other trios were played with Phil Minton, Michel Vorfeld and Georg Wolf.
The current duo with Philip Zoubek/Piano is "one of the best in duo improvisation" (Jean-Michel van Schouwburg), 2nd record out 2010 on Emanem.
1st duo record with old friend Georg Wolf on double bass in 2010. "Unchained Folk Songs" with very fine clarinet player Annette Maye. WIO Orchestra with Gunda Gottschalk, Erhard Hirt and 20 members, based in Wuppertal since 2007. Two new solo records out 2010: "Loverman hat nur eine Schwäche und die ist seine Stäke: er liebt", Paul Lovens wrote in the Liner Notes of "Loverman". the other one comprised the Cello Suites G major and D Minor of J.S.Bach.


When you are on a special day with your family&friends such as birthday, Thanksgiving day or Graduation ceremony and so on, you may need some digital camcorders to keep the memory for you. Many camcorder manufactories are trying their best to make their camcorders preciser and more portable. Sony also takes up much area in the market. They produce a number of camcorders which are popular around the world, such as Sony Cyber-shot RX100, Sony A77, Sony A57, Sony A65, Sony NEX-5n, NEX-VG20, NEX FS100 .etc. It's common for these users to have hundreds of MTS footage clips stored in the camera shotted in the journey or some special occasions. But problem turns up. If you are eager to edit these stored AVCHD videos in Avid Media Composer on you Mac to share with your friends&family members on computer or some portable devices, you may meet importing issues as the user below.
I am about to cut a half hour documentary from about 30 hours of AVCHD footage, shot on Sony FS100. I need to import the AVCHD mts clips into Avid Media Composer 5.5.3 but I am not sure exactly what codec is acceptable for them. Any suggestion are appreciated. Thank you!
Then how to bypass this kind of situation?
As we all know, Avid Media Composer is a type of computer software application known as a Non-linear editing system. The most compatible codec for Avid MC editing is DNxHD. So to solve these similiar issuses, the best solution here is to transcode Sony AVCHD to DNxHD MOV format. To the get work done, a third-party software is needed. Here Brorsoft MTS/M2TS Converter for Mac (can be used as a Mac AVCHD DNxHD Converter) is highly recommended to you. It's easy to use for conversion and editing and makes great output quality. Now just download it and follow the step-by-step guide to learn how to import your Sony AVCHD videos into Avid Media Composer for editing without any problem.
How to Convert Sony AVCHD MTS/M2TS clips to DNxHD MOV for Avid Media Composer?
Notes: If you are a Windows user and also want to make the MTS clips compatible with Avid Media Composer, Brorsoft MTS/M2TS Converter for Windows is your best choice. The steps are the same with above.
Assuming you've downloaded the excellent Sony AVCHD to Avid Converter to your Mac, install and run it. Click "Add" button on the main interface to load your MTS/M2TS camera recordings.
1. If necessary, you can click the button "Merge into one" to combine several videos to one file to save your conversion time.
2. If the supposed size of the imputed file is 1GB, then the memory space should be up to 40GB.
Click the format bar or the pull down menu of "Format" to select output format.
Just choose Avid Media Composer > Avid DNxHD(*.mov) as an output format.
Click "Convert" button to start converting Sony AVCHD MTS/M2TS video to DNxHD MOV for Avid Media Composer.
Once the conversion completes, simply click "Open" button to get the converted DNxHD MOV files. And now you can bring the output MOV files into Avid Media Composer to create your own masterpieces.
DNxHD is a proprietary Avid format, which is a video codec intended to be usable as both an intermediate format suitable for use while editing and as a presentation format. DNxHD offers a choice of three user-selectable bit rates: 220 Mbit/s with a bit depth of 10 or 8 bits, and 145 or 36 Mbit/s with a bit depth of 8 bits. DNxHD data is typically stored in an MXF container, although it can also be stored in a Quicktime container. Here Brorsoft Sony MTS Converter for Mac just packs it in a Quicktime (MOV) container for using in Avid Media Composer.


You need to change in order to grow. You can't grow if you just stay where you are. You can't grow if you don't change the way you think and act. In fact, changing your life is a continuous process. It never ends. The moment you stop changing, you stop growing.
I'm not saying that I know everything about changing life. I'm still learning myself. But here I'd like to share with you what I have learned so far.
Willingness is essential. It's your life; nobody can change it but you. If you aren't willing to change, then nothing in this world can make you do so.
To build the willingness to change, first you should realize that your life can be better than it is now. No matter how good your life is, it can always be improved. On the other hand, don't feel hopeless if your life doesn't seem good right now. You can always change your life for the better.
Accepting responsibility for your life is a must. Don't blame other people for the bad things that happen in your life. Don't blame your family, friends, boss, or the economy. Whether your life goes up or down depends on you and you alone. Once you take the responsibility, real change is within your reach.
Deep down in your heart, there are some principles that you know is true. Take the time to find them. What do you think is the most valuable thing in life? What principles do you think you must follow to live a fulfilling life? These are the values you need to align yourself with. Find them and remind yourself constantly about them.
Change is not easy because there is inertia you need to overcome. Just like a space shuttle needs a powerful rocket to overcome the Earth's gravity, you also need a powerful source of energy to overcome the inertia to change. Your cause is the source of energy you need. Your cause can give you the strength to overcome the inertia. To find your cause, find what matters to you.
Whenever you find one, write it down. After some time, look at your list. These are your limiting beliefs.
After identifying your limiting beliefs, you need to replace them with empowering beliefs. Write positive statements that counter the negative ones you wrote before and make positive affirmations using those statements. Do it whenever you realize that a limiting belief is at work.
Besides identifying limiting beliefs, you should also identify bad habits you have. Are there habits that drag you down? Are there habits that you know you need to break? List them all.
Then, rather than focusing on breaking those habits, focus on creating new positive habits that replace them. For example, let's say the bad habit is watching too much TV. Rather than focusing on reducing your TV time, you should focus on building a positive habit that will use the time in a better way. For instance, you might want to build the habit of reading.
Finding a mentor can greatly help you improve your life. Not only can your mentor give you advice on what to do in certain situations, he can also warn you about possible pitfalls in your path. Without a mentor, most likely you will have to learn many lessons the hard way. Having a mentor will save you serious amount of time.
Getting a good mentor is not easy though. In many cases, you can't just expect someone to invest his time in you for nothing. At the very least, you should show that you are an open-minded and teachable person. Furthermore, try to be useful to your mentor. Help him in any way you can to make his job easier. This way you send a message that you are a serious mentee that is worth investing in.
Having the right expectation from the beginning is important. Otherwise, it's easy for you to be discouraged when things don't go as expected. Change takes time, especially if you want the change to last. Having the right expectation prepares you to be persistent in difficult times.
The most difficult part is always the beginning. Once you go through it, things will become easier if you maintain the momentum. Just think about pushing a car. The most difficult part is getting the car to start moving. Once it's moving, pushing it will be easy as long as you don't let it stop again.
Similarly, you should keep improving your life. Change your life day by day. As the quote above says, if you don't change, you don't grow.
Once you take the responsibility, real change is within your reach.
Changing never ends. There is always room for improvement.
I like #6, I hate all of those phrases!
I think number 3 is a tough one. It's sometimes hard to leave your comfort zone and dare to take responsibility for what your life will be. With so much instability in the employment sector, I think more and more people are having to get on the steering wheels of their lives, and this causes fear.
Number 6 is also very important. I try making my son understand that what we say of ourselves influences our outcome. "I can", "I will find a way", "I am capable of" are affirmative orders that our minds execute one to one.
What do I love to do and why? Which values do I recall?
What do people around me think I'm good at?
What can I do easily?
Thanks Donald for this list!
Growth is change. Why are so many of us afraid of that word – change. I've always welcomed change…I guess I'm one of the minority that actually thrives in changing environments. However, most of the people I know are fearful of change. It just fascinates me.
Your #3 – Accepting Responsibility – is the hardest thing and also the first step. #8 – Find a Mentor – is a natural second step (in my analytical mind) considering that you're likely venturing into unfamiliar territory. A great support network is a booster shot to being successful.
I like your perspective Don!
Each of the points you shared is deep but contains a lot of truth.
Yes. I don't think we can ever be perfect, but we can always grow.
I hate them too :) Sadly, I sometimes still have them in my mind.
Yours is a nice list of question. I think the question "What makes you unique? What distinguishes you from everybody else?" is especially important for our career in the future.
A great support network is a booster shot to being successful.
This is very true. It makes a lot of difference if you have a strong support network behind you.
Your list is one of the best I've found. It's clean and simple. It's not rocket science.
I especially liked #8. Having a mentor has been very valuable for me. A common misconception is that a mentor has to spend a lot of time with you to be a effective. Lunch, a phone call or email can sometimes be just what you need to gain some perspective or insight into a problem.
This is a straightforward way to encourage human beings to take new levels of responsibility for their lives. Raising awareness builds self-nowledge and strengthens inner power. I have added this blog to the dreambuilders Australia blogroll.
I personally put a lot of attention on surrounding myself with positive people that encourage change and growth.
2. One can learn in the fields for which he or she has an "Aptitude".3. How far can he or she go , depends upon the 'Attitude' of individual.
If U can define 'Confidence' and how to differentiate between confidence & over-confidence , everything will be answered.
That's right. Self improvement is a continuous journey and that's why we must always change to grow.
A common misconception is that a mentor has to spend a lot of time with you to be a effective.
I agree. I don't spend a lot of time with my mentors but I learn a lot from them. The quality of time is more important than the quantity.
That's indeed an important part of personal growth. You become more and more like the people you surround yourself with.
I'm still learning myself so there are many things I don't know. Here I just shared my experience. Thanks for sharing your thoughts.
Please refer back to my question – 1. Definition of Confidence.
How to differentiate between Confidence & Over – confidence?
According to my experience :1. One learns only if He or She has a desire to learn.
2. Desire to learn depends on a) Aptitude & b) Attitude.
3. Motivation is purely the ability to change above 2 traits of a person.
4.It is also dependent on the skills of communication.
There are many other things which I desire to discuss to improve myself and I think that this process of exchanging Ideas and thoughts will be beneficial for all.
Thanks for the post–basic tips but these are things we often forget about when things aren't working out right. We will keep doing what we are doing and keep getting what we are getting and not think to go back through your tips and figure out the bad habits aren't working for us. Good reminder!
Those look like great tips to me.
Good post, I would add surrounding yourself with people who live to a higher standard than you currently do. Since we're influenced by our peers, these people will force you to grow beyond your comfort levels in a natural way. You'll pick up traits and habits that will help you improve your life.
I may be % wrong but in my personal opinion, If are surrounded by the persons of standards higher than that of urs, U may improve but there is every likelihood that U will first pick up their BAD Habits.
maintain them & improve upon.
Sometimes, to pick up a Good Habit, for which U have an aptitude also, may take years but one picks up bad habits in astonishingly short time but can't get rid of it even if He desires but does't have the kind of 'Will Power' required.
Take the example of Diego Maradoa & Other such celebrities, what happened to them. Persons who fell pray to bad habits are in billions ,but those who learn't from greats like; Martim Luther King, Mahatma Gandhi,Mother Terresa and other such great personalities, can be counted on fingers.
Not that we get inspired by such people as suggested by U, in most of the cases, its effect is very temporary.
Each & every person knows that they have to die one day and therefore should spend their life in a noble way, but how many really do that?
The moment U visit a cemetery, U get a feeling that life is really very short and we too would be ending up like this only and hence we should preserve and follow good and and noble traits only in the remaing life but,what happens in actual; the moment U are out, U come back in ur own world of Status.
In Sanskrit language, this feeling is termed as 'Smashan Vairagya'. Smashan- means cemetery& Vairagya means a feeling of detachment with awekening of all good traits ur supposed to inculcate, follow and reform. Since such feeling in ur mind remain till u are in cemetery and evaporates the moment U are out – " It is called as Smashan Vairagya".
It can't be right actually.
I'm totally agree with this. We must have change, because change is grow and without growing we aren't really living.
But actually it's right. when we change we grow, and for each step we grow we are getting closer and closer to our goal. Actually it's a help to us to reach it. Even if the changes is hard and difficult we must remember that we must take it as we take succes and happiness. Happy moments come and then go´. So remember if u are in a diffucult time remember that it won't be last forver (; Actually in the scool we learn't to or the teachers teach us and then we got to the exams. BUT in life we take the exam first and then teach of it. So always keep in your mind that we learn from mistakes so don't be afraid for changes.
BUT in life we take the exam first and then teach of it.
how can i change my personality to be nice..??
One thing, I'd like to add to this post is, surround yourself around people who are successful and all around "a good person". I really enjoyed this blog, thanks. I'm starting to change my life in a better, more positive way…starting today! Thanks keep up the great work.
Thanks for the kind words! And congrats for your good start. You can definitely make it.
I enjoyed reading your list and it is a very good build up and researched articles. – Every change is difficult, should be thought through and prepared.
thanks a lot.. it really helps.. ill try i mean ill do my best for a change in me.. for me, my family, relatives, friends and love ones..
thank you very much for opening my eyes on things that i have been trying very hard to fix my self into all this while. thank you very much.
you have made me to understand that it is always good to say something in the negative but rather is shoulld always be in the positive to as to be fulfilling in out destines. i will accept responsibilities, take total control of my environment, and start somewhere.
You want change? At 48, I sold all my worldly possessions that would not fit into a backpack and left my life in Los Angeles for a year-long adventure of a lifetime. I traveled through Thailand, Cambodia and Malaysia meeting some of the most incredible people and it was truly life changing. I was seriously stuck. I didn't want to live a moment longer working at some job or business I hated. During my adventure I became inspired. The stress in my body disappeared. I was sleeping all night, something I hadn't done for years… and i was in love with life again. I know that in my heart I love adventure and I love to have fun and so I dreamed up a way of sharing that with the world – Bondi Buddha. Today I live in Huntington Beach where I recently moved to pursue my love of surfing, the ocean, the beach and beach life. I do what is in my heart everyday, even it it means I surf all day. I am no longer about material possessions, in fact I live in a van! LOL. I know that any major success i may have will go towards helping others. I am a changed man and very happy : ) I say to anyone reading my little post here, it's never too late to change your life. You might have to make some sacrifices, but believe me when you are on the right path, you wont care.
I've been having a rough time the past couple months. I'm a young guy I just turned 22. Ive recently been having a round a bad luck. I know I need help to change how I am and the actions I make. You mentioned a mentor and that sounds great. My problem is I dont know how to meet people. I always feel like I am getting attacked or that someone is out to get me. So I avoid meeting new people and stick to a very close small handfull of people I regularly talk to. I wouldn't know where to look for a mentor at? Where in my city could I find that at? I live in Santa Fe, New Mexico. It's a very magical place I don't know the right word for it but its very "hippish" allot of earthly people. But i don't know where to even look. Please help me!
I thank you very much for driving me through the effective ways that i will right now start depend to. I secondly thank you for the time that you took to come up with such influencing and innovating ways that everyone has found so fit and useful to rely on. From now onwards you will be my second mentor on this communication channel.
Valuable suggestions . Just to add my thoughts if people are interested in a a form , I used a template document here https://goo.gl/hjpTCe.


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GameCo Launches Two New VGMs At The Tropicana Casino In New Jersey
J.R. Duren May 14, 2017
GameCo is at it again.
Recently the game developer announced it had launched a pair of new video game gambling machines (VGMs) in Atlantic City: two at Tropicana Casino & Resort and one at Harrah's Resort.
The new releases are additions to two other GameCo VGMs at Tropicana, Atlantic City Weekly said.
Basketball and roulette at Tropicana NJ casino
Gamblers at the Trop now have the option of playing GameCo's Nothin' But Net and Spread-Bet Roulette.
Nothin' but Net
Details on Nothin' but Net are sparse. But what we gathered from the GameCo website indicates that each round of betting involves 16 shots and can take wagers between $2 and $20.
Gamblers can choose between a male or female shooter, and all shots take place on an urban basketball court. These shots are a combination of lay-ups and jump shots from various places on the court and, like the NBA's three-point contest, include a money ball that's worth more points.
"Your skills will be challenged as you test your range from down-low to downtown," GameCo's description of the game reads. "Just don't miss the money ball!"
Spread-Bet Roulette
A press release from Tropicana provided further details about Spread-Bet Roulette, a game that has yet to have its own page on the GameCo site.
The roulette game is basically a spread bet with payouts as big as 400-to-1. Balls are dropped on an inner and outer wheel which spin simultaneously. Before they're dropped, though, a spread number is displayed and bet on.
When the balls stop, their corresponding numbers are added up and bettors win or lose based on their original spread bet.
[i15-table tableid=4301]
Two newbies add to pair of VGMs at Trop
As we mentioned earlier, Nothin' but Net and Spread-Bet Roulette will be added to the Trop's pair of GameCo VGMs: Danger Arena and Pharaoh's Secret Temple.
Danger Arena started the Atlantic City VGM craze when it debuted earlier this year. It was the first skill-based gambling terminal to appear in a United States casino.
GameCo uses the term "skill-based" to describe its games because their VGMs incorporate gaming skill into their platforms.
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redpajama_set_name: RedPajamaCommonCrawl


Father Craig began his tenure as Rector of St. John's Church in September, 2017. A native of New York, he was born in Albany, and spent his first eighteen years in a small town just south of Saratoga Springs, New York.
He attended Springfield College for his undergraduate studies (where he met his wife, Linda) and went on to complete a twenty-year military career as an Army Officer, serving honorably in a variety of positions with increasing responsibility. Father Craig holds two Master Degrees. His Master's of Divinity is from Oblate School of Theology (a Roman Catholic Seminary), and his Master's of Community Leadership is from Central Michigan University.
Linda and Craig have been married for over forty-three years and have two children and four grandchildren. Their daughter, Allison, is a high school English teacher, and their son, Matthew, is a Lutheran minister.
Father Craig believes everybody has a faith that holds them together on a daily basis. The image of Christ that embodies his priesthold is midwife...giving birth to faith...and his faith in Christ allows him to do that. The greatest gift Father Craig believes he can offer is his ability to listen compassionately.


text:
\section{Introduction}

The $\Lambda$-cold dark matter ($\Lambda$CDM) cosmological paradigm has been immensely successful at matching across cosmic time
observations spanning physical scales from the horizon length \cite[][]{planck2020} all the way down to galaxy scales \cite[e.g.,][]{chabanier2019},
and a vast menagerie of hypothetical non-baryonic elementary particles has been proposed to explain
the astrophysical data \cite[][]{feng2010}.  Cold dark matter particles have negligible thermal velocities in the matter-dominated era and
therefore clump gravitationally even on the smallest sub-galactic scales, a property that has caused persistent challenges with observations
of the abundances and density profiles of dwarf galaxies in the local Universe \cite[e.g.,][]{bullock2017}. Warm dark matter (WDM) is a
simple modification of CDM that has been proposed to suppress small-scale power and alleviate some of these
problems \cite[][]{bode2001}. WDM particles of a few keV have significant intrinsic velocities from having decoupled as thermal relics or
been produced by non-equilibrium processes, and one of the effects of their Mpc-range {\it free-streaming length} is to limit the gravitational collapse of structures and produce a cut-off in the matter power spectrum.

Intergalactic hydrogen at redshift $2\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} z \mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} 5$ scatters \hbox{\rm Lyman-$\alpha$}\ radiation and produces absorption features in the spectra of
distant quasars. This ``\hbox{\rm Lyman-$\alpha$}\ forest" is a powerful cosmological probe as it traces density fluctuations, the underlying dark matter
web-like distribution (the ``cosmic web"), and the ionization state and temperature of the intergalactic medium (IGM) at scales and
redshifts that cannot be probed by any other observable \cite[][]{hernquist1996a,croft1998,meiksin2009,mcquinn2016a}. The primary statistic
derived from spectroscopic data is the 1D power spectrum  of the flux distribution in the forest -- the
Fourier transform of the fractional flux autocorrelation function in velocity space --  which arguably provides the best tool for
distinguishing between CDM and WDM models \cite[][]{seljak2006,viel2013a,baur2016,garzilli2019,garzilli2021}. Interpreting such observations requires
expensive hydrodynamical simulations of the IGM that cover an extensive range of uncertain IGM photoionization and photoheating histories and
consistently maintain high resolution throughout a statistically representative sub-volume of the Universe, a traditional limiting factor
in previous analyses \cite[e.g.,][]{viel2013a,lukic2015a,Irsic+2017b,bolton2017,walther2021}. At present, the tightest lower limit
to the mass of a thermal WDM relic, $m_{\rm WDM}>1.9$ keV (95 percent CL), is obtained for highly conservative thermal histories of
intergalactic gas and without a marginalization over the properties of the cosmic ionizing background
\cite[][]{garzilli2021}.

In this Paper, we revisit these constraints in light of recent measurements with the {\it Keck} and {\it VLT} telescopes of the \hbox{\rm Lyman-$\alpha$}\ FPS down
to the smallest scales ever probed at redshifts $4\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} z\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} 5$ \cite[][]{boera2019a}, using a massive suite of 1080 high-resolution cosmological
hydrodynamics simulations that are part of the {\sc Cholla} IGM Photoheating Simulations (CHIPS) suite \cite[][]{villasenor2021a, villasenor2022}. High-redshift observations provide better limits on the mass of a WDM particle, as free-streaming becomes more prominent in velocity space and the effect of the non-linear evolution of the matter density field -- resulting in a
transfer of power from large scales to small scales -- is weaker at these epochs. There is also observational
evidence for a local minimum of the temperature of the IGM -- and therefore a corresponding minimum in the thermal cut-off
length scale -- in the redshift range $4 < z < 5$ \cite[][]{villasenor2022,gaikwad2020a}, making this era an optimal epoch
for deriving bounds on dark matter properties.

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_01.png}
    \caption{Impact of particle free-streaming on baryonic structures at $0<z<5.2$. The evolution of the gas density from a slice through the IGM was obtained from a subset of 8 CHIPS simulations where the mass of the warm dark matter particle \hbox{$m_{\rm{WDM}}$}\ was increased from 0.3 keV to $\infty$. All simulations assume the same gas thermal history from the best-fit model presented in \cite{villasenor2022}. Due to thermal pressure, the gas distribution is smoothed relative to the dark matter.
    }
    \label{fig:wdm_dens_slice}
\end{figure*}

\section{Basic equations and characteristic scales}

The hydrogen and helium photoheating ${\cal H}_i$ and photoionization $\Gamma_i$ rates per atom $i$ depend on the intensity of a uniform UV background radiation field $J(\nu,z)$ as

\begin{eqnarray}
\Gamma_i(z) &  =  & 4\pi \int_{\nu_i}^{\infty} \frac{J(\nu,z)}{h\nu} \sigma_i(\nu) d\nu, \\
{\cal H}_i(z) & = & 4\pi \int_{\nu_i}^{\infty} \frac{J(\nu,z)}{h\nu}\left(h\nu-h\nu_i\right) \sigma_i(\nu) d \nu,
\label{eq:photoionization_photoheating}
\end{eqnarray}
where $\nu_i$ and $\sigma_i(\nu)$ are the threshold  frequency and  photoionization cross-section, respectively. The total photoheating rate ${\cal H}$ is summed over the species $i=\,$\hbox{\rm H~$\scriptstyle\rm I$}, \hbox{He~$\scriptstyle\rm I$}, and \hbox{He~$\scriptstyle\rm II$}\ each of proper number density $n_i$, ${\cal H}=\sum_i n_i {\cal H}_i$. These rates, together with radiative recombinations, adiabatic compression, Compton and expansion cooling, and the gas density and peculiar velocity fields shaped by gravity and by pressure forces, fully determine the hydrogen \hbox{\rm Lyman-$\alpha$}\ absorption optical depth in velocity space $v$ \cite{hui97},

\begin{equation}
\tau_{v}={\sigma_\alpha c}\,\int \frac{n_{\rm HI}}{\sqrt{\pi} b H(z)}\, e^{-(v-u-v_p)^2/b^2} du.
\label{eq:tau}
\end{equation}
Here, $\sigma_\alpha=\pi e^{2} f_{12}/(m_{e} c
\,\nu_\alpha)$, $\nu_\alpha$ and $f_{12}$ are the frequency and upward oscillator strength of the \hbox{\rm Lyman-$\alpha$}\ transition, $b=(2k_BT/m_{\rm H})^{1/2}$ is the
Doppler parameter, $T$ the gas temperature,
$H(z)$ the Hubble parameter, $u$ and $v_p$
are, respectively, the real-space coordinate (in km s$^{-1}$) and the peculiar velocity along the line of sight, and we have assumed a Gaussian profile.
Denoting with $\bar z$ some mean redshift of interest, e.g. the redshift of a simulation output or the average redshift of any given data subset, one can write

\begin{equation}
u(x)= {H(\bar z)\over (1+\bar z)}(x-\bar x),
\label{eq:uvel}
\end{equation}
where $\bar x$ is the comoving position at which the redshift from Hubble expansion is exactly $\bar z$, and $H(\bar z)$ is the Hubble expansion rate. Line center in the rest frame of intervening hydrogen occurs at velocity $v=u+v_p$, which is related to the observed frequency $\nu_0$ by

\begin{equation}
\nu_\alpha=\nu_0(1+\bar z)\left(1+{v\over c}\right).
\end{equation}
Because of peculiar velocities, a photon observed at $\nu_0$ can have the same rest-frame frequency $\nu_\alpha$  at more than one place in its trajectory from the quasar to the observer.

In practice, only a limited range of $u$ values contributes to $\tau_v$, and one can replace in Equation (\ref{eq:tau}) $H(z)$ with $H(\bar z)$.
We can then define the flux contrast
$\delta_F(v)=F(v)/ \hbox{$\langle F \rangle$} -1$, where $F(v)=\exp(-\tau_v)$ is the flux at velocity $v$ and \hbox{$\langle F \rangle$}\ is the mean transmitted flux at a given redshift, and decompose each absorption spectrum into Fourier modes $\tilde \delta_F(k)$. Their variance as a function of the Fourier wavenumber $k=2\pi/v$ is the FPS over some velocity interval $\Delta v$,
\begin{equation}
P_F(k)=\Delta v\langle \tilde \delta_F(k)^2\rangle,
\label{eq:Pk}
\end{equation}
which is commonly expressed in terms of the dimensionless quantity $\Delta_F^2(k)=kP_F(k)/\pi$.

Four physical effects (cf. \citep{garzilli2019})
act to erase small-scale power in the FPS:

\begin{enumerate}[leftmargin=*]

\item {\bf Doppler broadening caused by gas thermal velocities along the line of sight.} Assuming a Gaussian smoothing kernel in the $\tilde
\delta_F(k)$ field of the form $\exp(-k^2\sigma_{\rm th}^2/2)$, where $\sigma_{\rm th}=(k_BT/m_{\rm H})^{1/2}$ is the broadening velocity scale, a cut-off in the FPS arises  then at the proper wavenumber
\begin{equation}
k_{\rm th}={1\over \sigma_{\rm th}}=0.11\,T_4^{-1/2}\,{\rm km^{-1}\,s},
\label{eq:kth}
\end{equation}
where $T_4\equiv T/10^4\,{\rm K}$.

\item {\bf Pressure support.} Pressure smooths
gas density fluctuations in the {\it spatial} Fourier domain with a Gaussian kernel \citep{gnedin1998,gnedin2003}
\begin{equation}
W(\tilde k, \tilde k_F)=\exp(-\tilde k^2/\tilde k_F^2),
\end{equation}
where $\tilde k$ is a comoving wavenumber,
\begin{equation}
\tilde k_F=g\tilde k_J=g\,{a\over c_s}
\sqrt{4\pi G\bar \rho}
\end{equation}
is the `filtering scale', and
$\tilde k_J$ is the wavenumber corresponding to the Jeans scale. Here,
$c_s=\left[5k_BT/(3\mu m_{\rm H})\right]^{1/2}$ is the sound speed, $\mu$ is the mean molecular weight ($\mu=0.61$ for an admixture of ionized hydrogen and singly ionized helium),
$\bar \rho$ is the mean total (dark matter plus baryons) mass density of the Universe, and $a$ is the scale factor. The $g$ factor accounts for the fact that the filtering scale depends on the prior thermal history of the IGM, and not just the instantaneous Jeans scale. Typically, $g>1$ after reionization \citep{gnedin2003}.

Mapping the 3D filtering scale to a broadening velocity
scale $\sigma_F=\sqrt{2}\,Ha/\tilde k_F$ along the line of sight results in a cut-off of the FPS at proper wavenumber
\begin{equation}
k_F={1\over \sigma_F}\simeq {\sqrt{3}g\over
2 c_s}={0.06\,g}\,T_4^{-1/2}\,{\rm km^{-1}\,s},
\label{eq:kF}
\end{equation}
where the second equality is valid at high enough redshifts. Under the physically-motivated assumptions that the gas temperature decays as $1/a$ after reionization completes around redshift $z\sim 6$, the factor $g\sim4-10$
at the redshifts $4\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} z\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$} 5.2$ of interest here \cite{gnedin1998}.
Pressure filtering, always lagging behind the growth of the Jeans length, is therefore subdominant compared to the thermal broadening of the absorption spectrum \cite{peeples10,kulkarni15,nasir16,boera2019a}.

\item {\bf Non-linear peculiar velocities in the gas.} Peculiar motions smear
power along line-of-sight (the ``fingers-of-God" effect")
over a range of scales comparable with the one-dimensional velocity dispersion. A fit to the results of numerical simulations with a Gaussian
in Fourier space yields \citep{gnedin2002}
\begin{equation}
\sigma_k=0.25~{\rm km^{-1}\,s} \left({k\over {\rm km^{-1}\,s}}
\right)^{1/2}.
\end{equation}
Setting $k=\sqrt{2}\sigma_k$, a cut-off in the FPS arises at proper wavenumber
\begin{equation}
k_v= 0.13\,{\rm km^{-1}\,s}.
\end{equation}

\item {\bf Dark matter free-streaming.} This effect can be described by the wavenumber, $\tilde k_{1/2}$, at which the WDM matter power spectrum is suppressed relative to
the CDM case by a factor of 2 \cite{viel2005},
\begin{equation}
\tilde k_{1/2}=4.25\,\left({\hbox{$m_{\rm{WDM}}$}\over 1\,{\rm keV}}\right)^{1.11}\,{\rm Mpc^{-1}}
\end{equation}
for a standard thermal relic. The conversion to a proper wavenumber in inverse km s$^{-1}$, $k_{\rm FS}=\tilde k_{1/2}/(aH)$, yields a cut-off in the FPS at
\begin{equation}
k_{\rm FS}=0.05\left({\hbox{$m_{\rm{WDM}}$}\over 1\,{\rm keV}}\right)^{1.11}\left({6\over 1+z}\right)^{1/2}\,{\rm km^{-1}\,s}.
\end{equation}
Note how the free-streaming cut-off moves toward larger scales (smaller $k$) at higher redshift.
\end{enumerate}

The numerical values of $k_{\rm th}, k_F,$ $k_v$, and
$k_{\rm FS}$ above suggest that free-streaming, thermal and velocity broadening effects all set in at similar scales. Thus, comparing the observations of the FPS to a large set of models that accurately depict the suppression on the FPS in the non-linear regime associated to each of these mechanisms is critical to constrain the WDM particle mass.
In the following section, we present our grid of simulations that evolve a total of 1080 models, which simultaneously vary the impact of free-streaming, Doppler broadening, and pressure smoothing. A comparison between  our grid of models and the observed FPS will provide new constraints on the mass of the dark matter particle that, for the first time, marginalize over all the important confounding physical effects.

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_02.png}
    \caption{ {\it Left:} Volume-weighted probability distribution function of the gas density at $z=4.6$ in WDM cosmologies compared to $\Lambda$CDM.
    Due to free-streaming, gas that otherwise would collapse into small-scale structures redistributes on larger scales. This suppressed collapse shifts the
    peak of the distribution closer to the mean density  $\bar{\rho}$.
    {\it Right:} Gas redistribution in WDM cosmologies results in an increase of the \hbox{\rm Lyman-$\alpha$}\ scattering optical depth of the IGM and a decrease of the transmitted flux $F$. Arrows display the decrease of the mean transmission \hbox{$\langle F \rangle$}\ as \hbox{$m_{\rm{WDM}}$}\ decreases.
    }
    \label{fig:dens_flux_distributions}
\end{figure*}

\section{Simulations}

The simulations used in this work were performed using the GPU-native MPI-parallelized code {\sc Cholla} \cite[][]{schneider2015a},
and evolve the equations of hydrodynamics on a uniform Cartesian grid while simultaneously tracking the non-equilibrium ionization
states of hydrogen and helium using the GRACKLE library \cite[][]{smith2017a}.  A spatially uniform, time-dependent UV radiation
background was assumed in the form of redshift-dependent photoionization
and photoheating rates per ion, $\Gamma_i$ and ${H}_i$, for the species \hbox{\rm H~$\scriptstyle\rm I$}, \hbox{He~$\scriptstyle\rm I$}, and \hbox{He~$\scriptstyle\rm II$}. The initial conditions at $z=100$ were generated using the
MUSIC code \cite[][]{Hahn+2011_Music} for a flat cosmology with parameters
$h = 0.6766$,
$\Omega_M = 0.3111$,
$\Omega_{\Lambda} = 0.6889$, $\Omega_b = 0.0497$, $\sigma_8 = 0.8102$, and $n_s = 0.9665$, consistent with constraints from Planck data \cite{planck2020}.
The initial conditions for all runs were generated from identical random number seeds to preserve the same amplitude and phase for all initial Fourier
modes across the simulation suite. The volume and numerical size of the simulations correspond to $L$ = 25 $h^{-1}$Mpc and $N$ = 2$\times$1024$^3$
cells and particles. All simulations
were run on the {\it Summit} computing system at the Oak Ridge National Laboratory.
The effect of a thermally produced WDM particle was introduced by modifying the input transfer function following the fitting formula of \cite{viel2005}, and no attempt was made to explicitly incorporate particle thermal velocities in the initial conditions \cite[][]{maccio2013}. WDM thermal velocities will be only a few percent of the velocities due to gravitational acceleration at the cosmic time of our initial conditions, and should not be important on the scales resolved by our simulations.

To compare the properties of the IGM in our simulations to observations, we extracted synthetic \hbox{\rm Lyman-$\alpha$}\ forest spectra measuring \hbox{\rm H~$\scriptstyle\rm I$}\ densities, temperatures, and peculiar velocities of the gas using 4096 skewers randomly distributed for each simulation along each axis of the box. The optical depth $\tau_v$ along each discretized line of sight was estimated as described in \cite{villasenor2021a}. From the set of lines of sight, we computed the transmitted flux and the mean one-dimensional power spectrum of the fractional transmission (see \S5.4 in \cite{villasenor2021a} for a detailed description).

\subsection{WDM Effects on the IGM}

The impact of particle free-streaming on the gas density structure of the IGM at fixed thermal history is shown in Figure \ref{fig:wdm_dens_slice}. The image displays a slice through the gaseous cosmic web at $0\le z \le 5.2$ generated from a set of 8 simulations that vary the mass of the dark matter particle \hbox{$m_{\rm{WDM}}$}\ increasing from 0.3 keV to $\infty$. The simulations follow the thermal history produced by the baseline photoheating and photoionization history presented in \cite{villasenor2022}.

The main effect of the free-streaming of keV particles on the matter density distribution is to suppress the formation of small-scale structure, reducing the clumpiness of the cosmic web. As free-streaming washes out small-scale inhomogeneities and decreases the concentration of overdense regions, baryon redistribution leaves an excess (relative to CDM) of close-to-mean density gas to permeate the IGM.
Figure \ref{fig:dens_flux_distributions} (left)
shows the change in the volume-weighted probability distribution function of the gas density at $z = 4.6$ for different \hbox{$m_{\rm{WDM}}$}\ cosmologies compared to a CDM simulation with the same thermal history.
The enhanced fraction of close-to-mean density as a
consequence of free-streaming increases the opacity of the IGM to \hbox{\rm Lyman-$\alpha$}\ scattering. Figure \ref{fig:dens_flux_distributions} (right) shows the probability distribution function of the \hbox{\rm Lyman-$\alpha$}\ transmitted flux $F$ along the skewer set for the WDM and CDM runs
at $z = 4.6$. The distribution of transmitted flux shifts to lower values with increasing free-streaming lengths.
The arrows at the bottom of the figure display the decrease of the mean transmission \hbox{$\langle F \rangle$}\ of the forest as \hbox{$m_{\rm{WDM}}$}\ decreases.

While free-streaming (in the regime $\hbox{$m_{\rm{WDM}}$} \geq 1\,$ keV) changes the IGM opacity it has a negligible effect on its density-temperature relation, often approximated with a
power-law model $T=T_0 (\rho / \overline{\rho})^{\gamma -1}$,
and the parameters $T_0$ and $\gamma$
are virtually unchanged -- for fixed photoionization and photoheating histories -- from the CDM case.

\subsection{WDM Effects on the Flux Power Spectrum}

\begin{figure}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_03.png}
    \caption{Transmitted FPS at $z=4.6$ from simulations that vary the WDM particle mass at fixed thermal history. The bottom panel displays the fractional difference relative to the CDM case. The suppression of small-scale structure due to free-streaming results in reduced power compared to CDM for $ k \gtrsim 0.02 \,\, \mathrm{ s \, km^{-1}}$. On large scales, the increase of the overall normalization compared to CDM is associated with the excess of close-to-mean density  gas and resulting reduction of the mean
    transmitted flux \hbox{$\langle F \rangle$}.  The gray bands
    denote the regions that fall outside the observational measurements of \cite{boera2019a}.
    }
    \label{fig:ps_wdm_effects}
\end{figure}

The suppression of small-scale density fluctuations from
free-streaming translates into
a decrease of the small-scale FPS compared to CDM. Figure \ref{fig:ps_wdm_effects} shows the dimensionless FPS of the \hbox{\rm Lyman-$\alpha$}\ transmitted flux, $\pi^{\mathrm{-1}} k P(k)$,
measured at $z=4.6$ in simulations with different WDM particle mass. The ratio of $P(k)$ with respect to the
standard CDM case is depicted in the bottom panel. Free-streaming  affects the FPS differently on small and large scales. On small scales, $k\gtrsim 0.02~\mathrm{s\, km^{-1}}$, the suppression of density fluctuations reduces power. On large scales,
$ k\lesssim 0.02~\mathrm{s \, km^{-1}}$, there is an increase of the overall normalization of \hbox{$P(k)$}\
associated with the reduction of the mean transmitted flux \hbox{$\langle F \rangle$}.

\subsection{Simulation Grid}

To constrain WDM cosmologies, we have performed an unprecedented grid of 1080 high-resolution simulations
(with $L$ = 25 $h^{-1}$Mpc and $N$ = 2$\times$1024$^3$) for a variety of particle masses \hbox{$m_{\rm{WDM}}$}\ and  thermal histories of the IGM that alter the impact of
free-streaming, Doppler broadening, and pressure smoothing on the forest FPS.
Here, we use the fiducial model for the hydrogen and helium photoionization and photoheating rates of \citep{villasenor2022}
(hereafter V22) as a template to generate different gas reionization and thermal histories.
The V22 photorates are a modification of the rates by \citep{puchwein2019a} and were determined
by running hundreds of cosmological simulations to
produce a reheating history in agreement with observations of the hydrogen \hbox{\rm Lyman-$\alpha$}\ FPS as well as the effective opacity of the \hbox{He~$\scriptstyle\rm II$}\ \hbox{\rm Lyman-$\alpha$}\ forest (see \citep{villasenor2022} for details).

Our grid of models is based on three different transformations of the V22 fiducial rates:

\begin{enumerate}[leftmargin=*]

\item We rescale the hydrogen (\hbox{\rm H~$\scriptstyle\rm I$}) and helium (\hbox{He~$\scriptstyle\rm I$}) photoionization rates $\Gamma_i$ by a constant factor $\beta$. This rescaling mainly impacts the neutral hydrogen (and helium) fractions, changing the mean transmitted flux \hbox{$\langle F \rangle$}\ and therefore the overall normalization of the FPS.

\item We modify the \hbox{\rm H~$\scriptstyle\rm I$}\ and \hbox{He~$\scriptstyle\rm I$}\ photoheating rates ${\cal H}_i$ by rescaling the mean energy of the ejected
photoelectrons $\mathcal{H}_i(z) / \Gamma_i(z)$
by a factor \hbox{$\alpha_\mathrm{E}$}. This modification
changes the temperature of the IGM and the impact of thermal Doppler broadening on
the small-scale FPS.

\item We change the timing of hydrogen reionization by offsetting the \hbox{\rm H~$\scriptstyle\rm I$}\ and \hbox{He~$\scriptstyle\rm I$}\ photoionization and photoheating rates by an amount $\Delta z$ -- a value $\Delta z>0$ shifts reionization to earlier times.
This shift affects the time available for the IGM to cool by adiabatic expansion and respond to thermally induced pressure gradients, changing the impact of pressure smoothing on the small-scale FPS.

\end{enumerate}

The transformations applied to the \hbox{\rm H~$\scriptstyle\rm I$}\ and \hbox{He~$\scriptstyle\rm I$}\ photorates described above can be expressed as

\begin{equation}
\begin{aligned}
\Gamma_i(z) &\rightarrow \beta \, \Gamma_i^{\mathrm{V22}}\,( z  - \Delta z), \\
\mathcal{H}_i(z) & \rightarrow \beta \, \hbox{$\alpha_\mathrm{E}$}\, \mathcal{H}_i^{\mathrm{V22}}( z - \Delta z).
\end{aligned}
\label{eq:rates_transformation}
\end{equation}
In this work we shall compare the results of our simulations to observational determinations of the FPS in the redshift range $4.2 \leq z \leq 5.0$. In the V22 model the IGM cools roughly adiabatically after reionization
at $z\sim6$ until AGNs begin to photoionize \hbox{He~$\scriptstyle\rm II$}\ and heat intergalactic gas at $z\sim 4.5$, resulting in a local minimum of the IGM temperature at this epoch. The effect of \hbox{He~$\scriptstyle\rm II$}\ reheating becomes dominant, however, only at $z<4$ and does not significantly impact the FPS at $z \geq 4.2$. Accordingly, we do not marginalize over the reionization history of helium, and fix the \hbox{He~$\scriptstyle\rm II$}\ photorates to those of V22.

Each model in our simulation suite is therefore characterized by the four-dimensional parameter vector $\theta = \{\hbox{$m_{\rm{WDM}}$}, \beta, \hbox{$\alpha_\mathrm{E}$}, \Delta z \}$, and
our parameter grid is shown in Table \ref{table:grid_parameters}. The range of dark matter masses were chosen to span from very light WDM ($\hbox{$m_{\rm{WDM}}$}=1$keV) to CDM. After running some
test calculations the ranges of thermal parameters ($\alpha$, $\beta$)
were chosen to encompass the parameter space with large
likelihood. The range of $\Delta z$ shifts span about 200 million years of cosmic time
around the end of reionization.
Full cosmological hydrodynamical simulations were performed for
all possible combinations of these four parameters, requiring
the suite of 1080 simulations used for our analysis.

\begin{table}
  \begin{threeparttable}
    \caption{WDM-CHIPS Simulation Grid\label{table:grid_parameters}}
     \begin{tabular}{cc}
        \toprule
        Parameter & Parameter Values \\ [2pt]
        \hline
        \hbox{$m_{\rm{WDM}}$} $\,$ [keV] $\,$ & 1, 2, 3, 4, 5, 6, 8, 12, 20, 40, 80, CDM\\
        $\beta$ & 0.6, 0.8, 1.0, 1.2, 1.4, 1.8 \\
        $\alpha_E$ & 0.1, 0.5, 0.9, 1.3, 1.7 \\
        $\Delta z$ & -0.5, 0.0, 0.5 \\
        \hline
     \end{tabular}
    \begin{tablenotes}
      \small
      \item NOTE.- The grid of models consist of the 1080 possible combinations of the parameters
           $\theta = \{ \hbox{$m_{\rm{WDM}}$}, \beta, \hbox{$\alpha_\mathrm{E}$}, \Delta z \}$. Each simulation evolves an $ L = 25 h^{-1} \mathrm{Mpc}$ and $N=2\times 1024^3$ box.
    \end{tablenotes}
  \end{threeparttable}
\end{table}

\subsection{Effects of Model Variations on the Flux Power Spectrum }
\label{sec:pk_variation}

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_04.png}
    \caption{ Effects of free-streaming (left), thermal broadening (center) and pressure smoothing (right) on \hbox{$P(k)$}\ at $z=4.6$,
    compared with the $P_0(k)$ measured from
    a simulation that adopts the V22 fiducial model ($\Lambda$CDM, $\beta =1$, $\hbox{$\alpha_\mathrm{E}$} =1$, and $\Delta z = 0$). Gray bands show the regions outside
    the observational measurements from \cite{boera2019a}. Free-streaming has the largest effect on the shape of \hbox{$P(k)$}\ relative to the fiducial CDM model, with suppression of $10-60$\% at $k\sim0.1\,\, \skm$ for $m_{\rm WDM}\sim5-2\,$keV. On smaller scales the free-streaming suppression saturates due to peculiar velocities (see text and Figure \ref{fig:ps_real_space}). Thermal broadening of lines induces a $10-20$\% effect at $k\sim 0.1\,\, \skm$ for mean IGM temperature changes of $\Delta T_0\sim1,000-2,000\,$K. Shifting the redshift of reionization by $\Delta z\sim0.5$ leads to differences in the impact of pressure smoothing of $1-2$\% at $k\sim0.1\,\,\skm$.
    }
    \label{fig:ps_effects_comparison}
\end{figure*}

Suppression of small-scale fluctuations in the \hbox{\rm Lyman-$\alpha$}\ forest can be attributed to decreased small-scale inhomogeneities in the intergalactic gas due to the
free-streaming of  WDM particles, but also to Doppler broadening of absorption lines and pressure smoothing of gas overdensities. Providing accurate constraints on the WDM particle mass from observations of the FPS requires differentiating the impact that these processes have on \hbox{$P(k)$}, and sampling over a dense set of models that simultaneously vary the effect of each mechanism.

Figure \ref{fig:ps_effects_comparison} illustrates the impact on the FPS of free-streaming (left), thermal broadening (center), and pressure smoothing (right) at $z=4.6$. Shown is the
ratio of the \hbox{$P(k)$}\ measured in simulations that independently vary the model parameters \hbox{$m_{\rm{WDM}}$}\ (left), \hbox{$\alpha_\mathrm{E}$}\ (center) and $\Delta z$ (right) to the
$P_0(k)$
measured from a simulation that adopts the fiducial V22 model corresponding to a $\Lambda$CDM cosmology and parameters $\beta =1$, $\hbox{$\alpha_\mathrm{E}$} =1$, and $\Delta z = 0$.
To isolate small-scale effects, for this comparison the \hbox{\rm Lyman-$\alpha$}\ optical depths of the skewers from each simulation were rescaled to produce the same \hbox{$\langle F \rangle$}\ of the fiducial model as this
equalizes \hbox{$P(k)$}\ on large scales. Additionally, for the simulations that vary $\Delta z$ (right), we separate the impact of pressure smoothing by also rescaling the instantaneous gas temperature along the skewers to have the same value at mean density $T_0$ as the fiducial model.
Variations of the model parameter $\beta$ mainly impact the ionization fraction of intergalactic hydrogen, changing the mean transmitted flux and thereby rescaling the overall normalization of the FPS. For a detailed analysis on this effect we refer the reader to Appendix B of \cite{villasenor2022}.

As shown in Figure \ref{fig:ps_effects_comparison} (center), the effect from increasing/decreasing the IGM temperature is to suppress/boost the FPS for
$k\gtrsim 0.01 \, \, \skm $ relative to the fiducial model. On these scales
\hbox{$P(k)$}\ is also altered by pressure smoothing (right). An earlier (later) reionization epoch suppresses (boosts) power as overdensities have more (less) time to respond to thermally-induced pressure gradients.
Figure \ref{fig:ps_effects_comparison}
also makes clear the small-scale \hbox{$P(k)$}\ behavior of
WDM models (left) relative to the fiducial CDM model.
The suppression of \hbox{$P(k)$}\ due to free-streaming with respect
to CDM increases with decreasing $\hbox{$m_{\rm{WDM}}$}$, and extends
to $k \geq 0.1 \,\, \skm$ where it saturates owing to
peculiar motions.
We argue that this important feature could be key for
constraining the nature of dark matter.

Interestingly, we find that if \hbox{$P(k)$}\ is measured in configuration (`real') space instead of redshift space (ignoring gas peculiar velocities) then the suppression of \hbox{$P(k)$}\ continues to $k \sim 0.2 \,\, \skm$. Figure \ref{fig:ps_real_space} displays the ratio $\hbox{$P(k)$} / P_\mathrm{CDM}(k)$ for simulations with WDM particle mass $\hbox{$m_{\rm{WDM}}$}=5 \, \mathrm{keV}$ (blue) and $\hbox{$m_{\rm{WDM}}$}=4 \, \mathrm{keV}$ (green). Dashed lines show the same ratio $\hbox{$P(k)$} / P_\mathrm{CDM}(k)$ but in this case the FPS is computed from synthetic spectra in real space. Here, the effective opacity of the skewers of the WDM simulations has been rescaled
to match CDM on large scales.

\begin{figure}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_05.png}
    \caption{ Suppression of \hbox{$P(k)$}\ due to free-streaming relative to CDM at $z=4.6$. The full lines show the ratio $P(k)/P_\mathrm{CDM}(k)$ where \hbox{$P(k)$}\ has been measured
    from the \hbox{\rm Lyman-$\alpha$}\ transmitted flux computed in redshift space. For the dashed lines the transmitted flux from the CDM and WDM case is computed in real space
    (ignoring peculiar velocities). In real space the suppression of \hbox{$P(k)$}\ due to free-streaming continues to $k \gtrsim 0.2 \,\, \skm$, while in redshift
    space the suppression saturates at $k \sim 0.1 \,\, \skm$.
    }
    \label{fig:ps_real_space}
\end{figure}

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_06.png}
    \caption{Observational determination of \hbox{$P(k)$}\ in the redshift range $4.2 \leq z \leq 5.0$ used in this work to constrain WDM cosmologies.
    The best-fit from the full WDM-CHIPS grid (purple) and the subset CDM grid (orange) are shown as lines and shaded regions which
    correspond to 95\% confidence range of \hbox{$P(k)$}\ marginalized over the posterior distribution.
    From our analysis, the \hbox{$P(k)$}\ from WDM cosmologies with $\hbox{$m_{\rm{WDM}}$} = 4.5^{+50} _{- 1.4} \,\, \mathrm{keV}$ ($2\sigma$ interval) is preferred
    over the best-fit CDM model. We note that the WDM best-fit results in lower IGM temperatures compared to the CDM best-fit
    (see Figure \ref{fig:temperature_best_fit}). The bottom panels show the fractional differences
    between the observations (blue points), the best-fit CDM model (orange line), and the overall best-fit WDM model (purple line), along with the model 95\% confidence intervals indicated with shaded regions.
    }
    \label{fig:ps_best_fit}
\end{figure*}

The comparison presented in Figure \ref{fig:ps_real_space} suggests that peculiar velocities play an influential
role shaping the structure of the \hbox{\rm Lyman-$\alpha$}\ forest on small scales.
We conclude that for $k \gtrsim 0.1 \,\, \skm$
peculiar velocities are more important for shaping \hbox{$P(k)$}\
than free-streaming.
Since peculiar velocities and thermal broadening on the smallest scales
affect WDM and CDM models
similarly, the decrease in \hbox{$P(k)$}\ from WDM relative to CDM saturates at $k \gtrsim 0.1 \,\, \skm$.

\section{Statistical Comparison}

In this section we present the observations of \hbox{$P(k)$}\ used for this work and we describe the methodology used for the Bayesian approach used in this work to constrain
the models used for our simulation suite.

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_07.png}
    \caption{Results from the Bayesian inference procedure, showing one- and two-dimensional projections of the posterior
    distributions for the parameters $\theta= \{ m_{\rm WDM}^{-1}, \beta, \,\alpha_E,\,\Delta z \}$
    recovered by fitting synthetic flux power spectra from our grid of WDM-CHIPS simulations to observations of the \hbox{\rm Lyman-$\alpha$}\ forest from \cite{boera2019a}. Gray bands in the 1D distributions show the $1\sigma$ and $2\sigma$ intervals. The marginalized likelihood for $1/m_{\rm WDM}$ peaks at $1/(4.5\,{\rm keV})$. The preference for a non-vanishing free-streaming length is only weakly statistically significant, as the CDM case is contained within the $3\sigma$ interval of the distribution. Our main result is a lower bound $\hbox{$m_{\rm{WDM}}$} > 3.1$ keV at the $2\sigma$ confidence level.
    }
    \label{fig:corner_wdm}
\end{figure*}

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=0.8\linewidth]{fig_08.png}
    \caption{Results from our MCMC procedure, showing one- and two-dimensional projections of the posterior
    distributions for the UVB parameters $\theta= \{ \beta, \,\alpha_E,\,\Delta z \}$. Here the sampling of models is restricted to the subset of 90 simulations that evolve a CDM cosmology. Gray bands in the 1D distributions show the $1\sigma$ and $2\sigma$ intervals.
    }
    \label{fig:corner_cdm}
\end{figure*}

\subsection{Observational Flux Power Spectrum }

For this work we employ observations of the \hbox{\rm Lyman-$\alpha$}\ forest power spectrum from the Keck observatory and the Very Large Telescope, presented in \cite{boera2019a}.
These measurements represent the highest resolution determination of \hbox{$P(k)$}\ to date and probe the structure of the forest in the redshift range $4.2 \leq z \leq 5.0$.
Since the impact of free-streaming on \hbox{$P(k)$}\ is greater at high redshift
 the data set from \cite{boera2019a} is arguably the most constraining determination of \hbox{$P(k)$}\
to infer the nature of dark matter currently available.
The measurements of \hbox{$P(k)$}\ from \cite{boera2019a} along our best-fit determination obtained from our analysis are shown in Figure \ref{fig:ps_best_fit}.

\subsection{MCMC Inference}
\label{sec:mcmc_inference}

To constrain WDM cosmologies from the observations of \hbox{$P(k)$} , we use an MCMC approach to sample over our suite of models and obtain best-fit distributions for our
parameters. The likelihood function for the model given by the parameters $\theta= \{m^{-1}_{\rm WDM}, \beta, \,\alpha_E,\,\Delta z\}$ is evaluated as

\begin{equation}
\ln \mathcal{L}(\theta) =   - \frac{1}{2}  \sum_z \left[  \mathbf{\Delta}^{T} \mathbf{C}^{-1} \mathbf{\Delta} +  \ln \operatorname{det}(\mathbf{C}) + N \ln 2 \pi  \right],
\label{eq:mcmc_likelihood}
\end{equation}
\noindent
where $\mathbf{\Delta}$ denotes the difference vector between the observational \hbox{$P(k)$}\ and the model $\mathbf{\Delta} = P_{\mathrm{obs}}(z,k) - P(z,k|\theta)$, and
$\mathbf{C}$ corresponds to the covariance matrix associated with the observation of \hbox{$P(k)$}\  as reported by \cite{boera2019a}. To compute $P(z,k|\theta)$ for arbitrary
values of the parameters $\theta$ not directly simulated by our grid, we perform a four-dimensional interpolation of the sixteen neighboring simulations in parameter space.

The methodology for our
inference approach differs from previous works in a number of key respects:

\begin{enumerate}[leftmargin=*]
\item Our WDM-CHIPS simulation grid captures a wide range of  free-streaming lengths and UVB models to sample over a variety of cosmic structure formation and gas thermal histories, and thereby produce different
statistical properties for the \hbox{\rm Lyman-$\alpha$}\ forest. Due to the computational cost of the simulations, evolving
such a large grid of high-resolution cosmological hydrodynamical simulations
had not been achieved before. With the advent
of efficient numerical codes like {\sc Cholla}  and capable systems like Summit, it is now possible to simulate thousands of models.

\item We evaluate the performance of a given model in matching the observations of \hbox{$P(k)$}\ by marginalizing over the self-consistently evolved hydrogen reionization history
in the redshift interval $4.2\leq z\leq 5.0$. The IGM thermal properties at one redshift cannot be disentangled from its properties at previous epochs, thus the marginalization over the parameter posterior distributions should not be performed independently at each redshift \cite[c.f.][]{bolton2014a, nasir16, hiss2018a,  boera2019a,   walther2019a, gaikwad2020b}).

\item We do not modify, in post-processing, the mean transmitted flux \hbox{$\langle F \rangle$}\ in the forest by rescaling the \hbox{\rm Lyman-$\alpha$}\ optical depth, nor do we assume an instantaneous power-law temperature-density relation (cf. \cite{viel2013a, Irsic+2017b, boera2019a, walther2021}).
The latter does not accurately reproduce the thermal state of IGM gas in the range $-1 \leq \log_{10} \Delta \leq 1$. Instead, in our approach simulations self-consistently evolve
the ionization and thermal structure of the IGM determined by the wide range of photoionization and photoheating histories applied in our model grid.
\end{enumerate}

\begin{figure}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_09.png}
    \caption{One-dimensional posterior likelihood for the WDM particle mass obtained by limiting the observational measurements of \hbox{$P(k)$}\ \cite{boera2019a}
    to $k \lesssim 0.1 \, \skm$ compared to the likelihood distribution from fitting to
    the complete data set (dashed blue). The limited data set for the observational \hbox{$P(k)$}\ is constructed by excluding the last three points of each redshift snapshot. Gray bands show the $1\sigma$ and $2\sigma$ interval from the fit to the limited data. In this case $\Lambda$CDM is the
    preferred cosmology and the lower limit at 95\% confidence shifts to $\hbox{$m_{\rm{WDM}}$} > 3.6 \, \mathrm{keV}$ compared to $\hbox{$m_{\rm{WDM}}$} > 3.0 \, \mathrm{keV}$ from
    the fit to the full data set. }
\label{fig:mwdm_limited_data}
\end{figure}

\begin{figure}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_10.png}
    \caption{Redshift evolution of the temperature $T_0$ of IGM gas at the mean density
    from the best-fit $\Lambda$CDM and WDM models (solid lines) and $1\sigma$ interval (colored bands) obtained from our MCMC analysis.
    The data points show the values of  $T_0$ inferred from observations of the \hbox{\rm Lyman-$\alpha$}\ forest by \cite{boera2019a} and \cite{gaikwad2020a}.
    The best-fit from WDM cosmologies have moderately lower temperatures compared to CDM, which compensates for the suppression of small-scale
    \hbox{$P(k)$}\ due to free-streaming.
    }
\label{fig:temperature_best_fit}
\end{figure}

\section{Results}

By comparing the high-resolution observation of the flux power spectrum from \cite{boera2019a} to our suite of simulations that simultaneously vary the impact of
free-streaming from WDM cosmologies
on the matter distribution and different reionization and thermal histories of the IGM, we infer new constraints on the WDM particle mass \hbox{$m_{\rm{WDM}}$} . In this section we present the
posterior distribution from our MCMC analysis and the marginalized \hbox{$P(k)$}\ and thermal evolution of the IGM for our best-fit models. To complement our results, we repeat our analysis
by modifying \hbox{$P(k)$}\ from the simulations to account for a non-uniform UV background, and finally, we show hypothetical constraints on \hbox{$m_{\rm{WDM}}$}\ from an artificially increased number of quasars.

\subsection{Distribution of the Model Parameters}

The posterior distribution of our four model parameters $\theta= \{ m_{\rm WDM}^{-1}, \beta, \,\alpha_E,\,\Delta z \}$ resulting from the Bayesian inference procedure is
shown in Figure \ref{fig:corner_wdm}. A clear global maximum of the 1D marginalized distributions is shown for \hbox{$m_{\rm{WDM}}$}\ and the parameters $\beta$ and \hbox{$\alpha_\mathrm{E}$}\ responsible
for rescaling the photoionization and photoheating rates. The distribution of the parameter $\Delta z$ is not fully contained by our grid of models, but we
argue that this issue does not represent a significant challenge to our conclusions. Values of $\Delta z < -0.5$ would reduce the suppression of small-scale \hbox{$P(k)$}\
from pressure smoothing which could be compensated by free-streaming or thermal broadening, possibly shifting our constraint of \hbox{$m_{\rm{WDM}}$}\ to slightly lower values.

The marginalized distribution for $m_\mathrm{WDM}^{-1}$ (top left panel, Figure \ref{fig:corner_wdm}) is well constrained and it peaks at $m_\mathrm{WDM}^{-1} = 1 /(4.5 \, \, \mathrm{keV})$. Arguably, the preference for a non-zero free-streaming length is weakly significant as the CDM cosmology is contained within the $3\sigma$ interval of the marginalized distribution. The principal result from our analysis is the lower limit $\hbox{$m_{\rm{WDM}}$} > 3.0 \, \mathrm{keV}$ (at $2\sigma$ level) obtained for
the WDM particle mass.

To find the best-fit model to \hbox{$P(k)$}\ for a CDM cosmology, we repeat our MCMC approach but restricted to the models that evolve the
$\Lambda$CDM cosmology varying only the photoionization and photoheating history. Figure \ref{fig:corner_cdm} shows the one- and two-dimensional
projections of the posterior distribution for the UV background (UVB) parameters $\{ \beta, \,\alpha_E,\,\Delta z \}$ obtained from the comparison of \hbox{$P(k)$}\ from \cite{boera2019a}
to the grid of 90 CDM simulations.
The posterior distribution of the UVB parameters from our CDM fit differs slightly from the distribution of parameters
obtained from the inference that included WDM cosmologies (see Figure \ref{fig:corner_wdm}). The main difference between the two distributions
is that the parameters $\beta$ and \hbox{$\alpha_\mathrm{E}$}\ peak at slightly shifted values. In particular, the product $\beta \, \hbox{$\alpha_\mathrm{E}$}$, which rescales the photoheating rates, is higher
for the CDM case. Higher photoheating rates directly result in increased IGM temperatures (see section \ref{sec:temperature_evolution}).

\subsection{Best-Fit Power Spectrum}

The marginalized flux power spectrum \hbox{$P(k)$}\ over the posterior distribution obtained from our MCMC analysis along
the observational data used to constrain the model is shown in Figure \ref{fig:ps_best_fit}. Lines and shaded regions
show the best-fit \hbox{$P(k)$}\ and the 95\% confidence range. The result from the fit performed by sampling over the entire WDM model grid (purple)
and restricting to the CDM grid (orange) are shown separately. As shown, both results provide a good match to the observed \hbox{$P(k)$}\, nevertheless,
the relative difference between the model and the data quantified as $\chi^2= \sum_z  \Delta^{T} \mathbf{C}^{-1} \Delta$ is slightly lower for the best-fit
WDM model ($\chi^2= 38.3$), compared to $\chi^2= 40.9$ from the CDM best-fit model. Here $\mathbf{C}$ denotes the covariance matrix taken from \cite{boera2019a}
and $\Delta$ is the difference vector between the observed and model \hbox{$P(k)$} .

We find that the preference for a non-zero free-streaming scale derived from our analysis is driven by the smallest scales probed by the high-resolution
measurement of \hbox{$P(k)$}\ from \cite{boera2019a}.
We repeated our inference methodology but excluding the three last data points ($k > 0.1 \,\, \skm$) from the likelihood calculation. Here we
found that excluding the high-$k$ measurements places $\Lambda$CDM as the preferred cosmology.
The marginalized posterior distributions for \hbox{$m_{\rm{WDM}}$}\ from the fits limited to
$k \leq 0.1 \,\, \skm$ and to full data set are displayed in Figure \ref{fig:mwdm_limited_data}. As shown, the likelihood peaks at CDM and the lower limit constraint
at the $2\sigma$ level shifts to $\hbox{$m_{\rm{WDM}}$} > 3.6 \, \mathrm{keV}$.

In section \ref{sec:pk_variation} we showed that free-streaming and Doppler broadening impact \hbox{$P(k)$}\ differently on small scales ($k > 0.1 \, \skm$). As the temperature of
the gas is increased/decreased, the impact of thermal broadening is to decrease/increase the small-scale \hbox{$P(k)$}\ .
While free-streaming decreases small-scale density fluctuations, its effect on the flux power spectrum saturates at $k \gtrsim 0.1 \, \skm$
due to the impact from peculiar velocities
(see Figs. \ref{fig:ps_effects_comparison}, \ref{fig:ps_real_space}).

We have shown that the preference for a WDM cosmology over $\Lambda$CDM
originates from the $k> 0.1 \, \skm$ measurement of \hbox{$P(k)$} . Also, we showed that on these scales ($k> 0.1 \, \skm$) the suppression of \hbox{$P(k)$}\ due to free-streaming saturates
while the suppression of \hbox{$P(k)$}\ from thermal broadening increases monotonically. Therefore, we conclude that the saturated suppression
of \hbox{$P(k)$}\ due to a $\hbox{$m_{\rm{WDM}}$} \sim 4.5 \, \mathrm{keV}$ combined with a moderately lower IGM temperature
provides a slightly better fit to the $k> 0.1 \, \skm$ observation of \hbox{$P(k)$}\ compared to the $\Lambda$CDM best-fit model with
higher IGM temperatures at $4 \leq z \leq 5$ (see Fig. \ref{fig:temperature_best_fit}).

\subsection{Thermal Evolution of the IGM}
\label{sec:temperature_evolution}

One of the advantages of our approach compared to previous works that aim to constrain the WDM free-streaming from observations of the \hbox{\rm Lyman-$\alpha$}\ forest power spectrum is that
our simulations self-consistently evolve the IGM thermal and ionization history during and after reionization by sampling over a large grid models that vary the UVB photoionization and
photoheating rates. Instead, the methodology adopted by previous works \cite{viel2013a, Irsic+2017b, garzilli2019, garzilli2021} was to change the temperature $T_0$ and the ionization fraction of the IGM in post-processing by rescaling $T_0$ and the effective optical depth \hbox{$\tau_{\mathrm{eff}}$~} of the simulated skewers.

Figure \ref{fig:temperature_best_fit} shows the redshift evolution of the temperature of the gas at mean density $T_0$ marginalized over the posterior distribution
from our MCMC analysis; shaded bars show the $1\sigma$ interval. The best-fit model for WDM cosmologies with $\hbox{$m_{\rm{WDM}}$}=4.5\,$keV results in moderately lower ($5-10$\%)
IGM temperatures (purple)
due to the slightly reduced photoheating rates compared to the $\Lambda$CDM best-fit model (orange). Lower temperatures are expected from the WDM models as they decrease the impact of
thermal broadening in suppressing \hbox{$P(k)$}\ which compensates
for the suppression due to free-streaming.

In Figure \ref{fig:temperature_best_fit}, we compare the IGM temperature $T_0$ inferred by this work to other measurements at $z>4$ \cite{boera2019a, gaikwad2020a}.
The high-redshift inference presented by \cite{gaikwad2020a} was obtained by characterizing the transmission spikes observed in $z>5$ spectra.
The thermal histories obtained from our analysis are consistent with the results from \cite{gaikwad2020a}, suggesting a peak in $T_0$ due to hydrogen reonization at $z \sim 6$.

The measurement of $T_0$ presented in \cite{boera2019a} for $4.2 \leq z \leq 5.0$ was made by fitting the observed \hbox{$P(k)$}\ to simulated spectra according to a $\Lambda$CDM cosmology
where the instantaneous density-temperature distribution of the gas is modified in post-processing changing parameters $T_0$ and $\gamma$ from the power-law relation
$T= T_0 (\rho/\bar{\rho})^{\gamma-1}$. Despite using the same observational determination of \hbox{$P(k)$}\ for our inference, the IGM temperatures obtained in this work during
$4.2 \leq z \leq 5.0$ are slightly higher than those inferred by \cite{boera2019a}.
Restricting to a $\Lambda$CDM cosmology, we find a best-fit $T_0$ is 15 - 20\% higher
at redshift $z=5.0$ and $z=4.6$ compared to the result from \cite{boera2019a}. At redshift $z=4.2$ the difference lowers to 10 - 15\% and our result agrees with their inference within $1\sigma$. The evolution of $T_0$ from our best-fit WDM model is also higher (5 - 10\%) than the results from \cite{boera2019a}, but in this
case our results also agree to within $1\sigma$.

\begin{figure}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_11.png}
    \caption{One-dimensional posterior likelihood for the WDM particle mass obtained by fitting to the measurements of the FPS from \cite{boera2019a}
    but with an artificially reduced uncertainty motivated by the improved statistics of \hbox{\rm Lyman-$\alpha$}\ spectra from upcoming surveys. Here we rescale
    the covariance matrix $\mathbf{C}$ of \hbox{$P(k)$}\ by a factor of one-fourth. In this hypothetical case, the constraint on \hbox{$m_{\rm{WDM}}$}\ is tighter,
    measured as $\hbox{$m_{\rm{WDM}}$} = 4.5_{-1.0}^{+1.9} \, \mathrm{keV}$ at 95\% confidence level. The dashed line shows our result
    from fitting to \hbox{$P(k)$}\ with the reported uncertainty from \cite{boera2019a}.
    }
\label{fig:mwdm_reduced_sigma}
\end{figure}

\begin{figure*}[htb!]
    \centering
    \includegraphics[width=\linewidth]{fig_12.png}
    \caption{
    Posterior distribution of the parameters $\theta= \{ m_{\rm WDM}^{-1}, \beta, \,\alpha_E,\,\Delta z \}$ from fitting the observed \hbox{$P(k)$}\ from \cite{boera2019a}
    with models that account for a patchy reionization according to the modification to \hbox{$P(k)$}\ presented in \cite{Molaro+2022}. In this case,
    the preference for a WDM cosmology persists but the distribution shifts to higher mass. The likelihood peaks at $\hbox{$m_{\rm{WDM}}$} = 7.1 \, \mathrm{keV}$ and the lower limit at the
    95\% levels is $\hbox{$m_{\rm{WDM}}$} = 3.8 \, \mathrm{keV}$. In this case the $\Lambda$CDM cosmology is contained within the 95\% interval of the distribution. The dashed blue
    lines show the one-dimensional likelihood distributions obtained from fitting \hbox{$P(k)$}\ measured directly from the uniform UVB simulations.
    }
    \label{fig:corner_wdm_inhomogeneous}
\end{figure*}

\subsection{Constraining WDM with Increased Quasar Sightlines}

Upcoming surveys of the \hbox{\rm Lyman-$\alpha$}\ forest (e.g., DESI \cite{desi2016a}, WEAVE \cite{Pieri+2016}, EUCLID \cite{Amiaux+2012}, LSST) will drastically increase the available
observations of quasar sightlines, which will significantly improve the statistics of measurements derived from the forest. The improved statistics will allow tighter constraints on cosmological parameters as well as on WDM and the sum of the neutrino masses from their role in suppressing small-scale structure in the forest.

To assess how better statistics would impact the constraining power of high-redshift and high-resolution observations of the \hbox{\rm Lyman-$\alpha$}\ forest for WDM cosmologies, we repeat our analysis but
decreasing the uncertainty on the observed \hbox{$P(k)$}\ by a factor of one half, which would correspond to increasing the number of
observed quasar spectra from fifteen used by \cite{boera2019a} for their measurement of \hbox{$P(k)$} , to about sixty (a factor of four increase).

In our approach, we approximate a more constraining dataset by rescaling the covariance matrix $\mathbf{C}$ of \hbox{$P(k)$}\ by a factor of one-fourth in Equation  (\ref{eq:mcmc_likelihood}).
Note that the observational measurements of the FPS  are not altered, and only the covariance matrix is reduced.
Figure \ref{fig:mwdm_reduced_sigma} shows the marginalized likelihood for $\hbox{$m_{\rm{WDM}}$}^{-1}$ obtained from our analysis using the reduced uncertainty. In this hypothetical case, the
improved statistics of the \hbox{$P(k)$}\ measurement provide a tighter constraint for the WDM particle mass measured as $\hbox{$m_{\rm{WDM}}$} = 4.5_{-1.0}^{+1.9} \, \mathrm{keV}$ at the 95\% confidence level.
This exercise demonstrates that increasing the sample of high-$z$ and high-resolution observations of the \hbox{\rm Lyman-$\alpha$}\ forest should place tight constraints on WDM cosmologies.

\subsection{Modified $P(k)$ for Inhomogeneous UVB }

One of the main limitations of our analysis
is that the WDM-CHIPS simulations evolve under a homogeneous UVB in the form of uniform photoionization and photoheating rates.
We evaluate the effect of this assumption on our conclusions by repeating our analysis but using the modification to \hbox{$P(k)$}\ prescribed
by \cite{Molaro+2022} to account for the impact of a nonuniform UVB on the simulated \hbox{$P(k)$} .

In \cite{Molaro+2022}, a set of simulations that apply a uniform UVB were compared to a set that follows a hybrid-RT method.
For the latter, spatially-varying maps for the \hbox{\rm H~$\scriptstyle\rm I$}\ photoionization and photoheating rates were computed in post-processing
and used as input for a re-run of the base simulation, incorporating the response of the gas to the non-uniform photoionization and photoheating. For the comparison, pairs
of uniform and nonuniform UVB simulations were calibrated to have the same average ionization and thermal history. The authors concluded that simulations with a patchy reionization show a suppression ($10-15$\%) of the FPS on small scales ($k\sim 0.1\,\skm$) with
respect to the uniform UVB case. This effect is mainly driven by the Doppler broadening associated with the high temperatures of recently ionized regions and the divergent
peculiar velocities of thermally pressurized gas. On large scales ($k > 0.03 \, \skm$) the variation of the IGM neutral fraction due to large-scale fluctuations of the gas temperature leads to an increase on \hbox{$P(k)$}.

The likelihood distribution from our MCMC inference where we modify the \hbox{$P(k)$}\ from each one of the simulations in our WDM-CHIPS grid to account for an
inhomogeneous reionization according to the transformation presented in \cite{Molaro+2022} is shown in Figure \ref{fig:corner_wdm_inhomogeneous}. Dashed blue lines correspond to
the one-dimensional marginalized distributions obtained from fitting the base \hbox{$P(k)$}\ from the simulations with a uniform reionization.

Figure \ref{fig:corner_wdm_inhomogeneous} shows that modifying the models \hbox{$P(k)$}\ to account for patchy reionization mainly affects the likelihood of \hbox{$m_{\rm{WDM}}$}.
While WDM cosmologies are still preferred over $\Lambda$CDM when fitting the non-uniform UVB models, the likelihood shifts to higher values of \hbox{$m_{\rm{WDM}}$}\ compared to the result
from uniform UVB models. An inclination for models with reduced free-streaming compensates for the reduction of small-scale \hbox{$P(k)$}\ due to patchy reionization. In this case the
maximum likelihood occurs at $\hbox{$m_{\rm{WDM}}$} = 7.1 \, \mathrm{keV}$ and the lower limit at 95\% level is at $\hbox{$m_{\rm{WDM}}$} =  3.8 \, \mathrm{keV}$. Notably, for the patchy
UVB models, the $\Lambda$CDM cosmology is contained within the 95\% interval of the likelihood distribution.

We note that the difference between the observed and model \hbox{$P(k)$}\ defined as $\chi ^2 = \sum_z   \mathbf{\Delta}^{T} \mathbf{C}^{-1} \mathbf{\Delta} $
(see \S\,\ref{sec:mcmc_inference} is larger for the nonuniform UVB modified best-fit models compared to the best-fit models sampling from the uniform UVB simulated \hbox{$P(k)$} .
When fitting with \hbox{$P(k)$}\ measured directly from the uniform UVB simulations, we measure $\chi^2 = 38.3 $ for the best-fit model with $\hbox{$m_{\rm{WDM}}$} = 4.5 \, \mathrm{keV}$
and a slightly higher $\chi^2 = 40.9 $ for the $\Lambda$CDM best-fit model.
On the other hand, when sampling over the modified \hbox{$P(k)$}\ to account for patchy reionization, we measure larger values $\chi^2 = 46.4$ and $\chi^2 = 46.6$ for the
WDM and CDM best-fit models, respectively.
The higher values of $\chi^2$ obtained for the patchy reionization modified models show that, in the context of this work, \hbox{$P(k)$}\ measured directly from the uniform UVB simulations provide a better match to the
observation from \cite{boera2019a}, therefore we use the likelihood distribution obtained from the sampling over the uniform UVB models to construct the main results from our analysis.

\section{Conclusions}

To constrain
cosmological models where dark matter free-streaming smooths the matter distribution in the Universe, we have used the GPU-native code {\sc Cholla}
to perform a massive suite of high-resolution hydrodynamical cosmological simulations that simultaneously vary the effect of free-streaming from WDM particles and
the IGM reionization history.
We compare the power spectrum of the synthetic \hbox{\rm Lyman-$\alpha$}\ forest from our simulations to the high-resolution observational measurement presented by \cite{boera2019a} to determine via a
likelihood analysis the optimal model for cosmological free-streaming that best matches the observation. A summary of the efforts and conclusions from this work follows.

\begin{itemize}

\item We present the WDM-CHIPS suite consisting of a grid of 1080 high-resolution simulations ($ L = 25 h^{-1} \mathrm{Mpc}$, $N=2\times1024^3$) that vary the free-streaming from WDM
cosmologies and the photoionization and photoheating rates from the metagalactic UVB. The UVB rates applied for our grid use the model from \cite{villasenor2022} as a template,
and use three parameters that control a rescaling amplitude and redshift-timing of the hydrogen photoionization and photoheating rates. Combined with the WDM particle mass \hbox{$m_{\rm{WDM}}$} ,
our four-dimensional grid of models densely sample a wide range of self-consistently evolved reionization and thermal histories of the IGM. This represents a significant improvement
over previous studies that aimed to constrain WDM cosmologies from observations of the \hbox{\rm Lyman-$\alpha$}\ forest  \cite{viel2005, viel2013a, Irsic+2017b, garzilli2019, garzilli2021}.

\item The large range of thermal histories produced by the different UVB models in our grid of simulations results in synthetic measurements of \hbox{\rm Lyman-$\alpha$}\ spectra where the
impact from Doppler broadening and pressure smoothing on suppressing the small-scale \hbox{$P(k)$}\ varies widely.
This flexibility is important as these mechanisms have similar effects
as free-streaming decreasing small-scale fluctuations in the \hbox{\rm Lyman-$\alpha$}\ forest. Additionally, our approach does not require an assumption of a power-law relation
for the density-temperature distribution of the gas.
Self-consistent evolution of the IGM phase structure
proves to be important as we find that a single power law does not accurately describe the $\rho_\mathrm{gas}-T$
distribution in the density range relevant to generating the signal of the \hbox{\rm Lyman-$\alpha$}\ forest (see Appendix E of \cite{villasenor2022}).

\item We compare our grid of models to the high-redshift ($4.2 \leq z \leq 5.0$) observational measurement of the \hbox{\rm Lyman-$\alpha$}\ forest power spectrum from \cite{boera2019a}.
The observations presented in \cite{boera2019a} provide the highest resolution measurement
of \hbox{$P(k)$}\ at the time that work was executed. We perform a Bayesian MCMC sampling to determine the best-fit model for free-streaming
due to WDM cosmologies and the IGM photoionization and photoheating history.

\item From our MCMC analysis, we find that a cosmological model with non-vanishing free-streaming is preferred over $\Lambda$CDM. The best-fit and 95\% interval for the
WDM particle mass from our result is $\hbox{$m_{\rm{WDM}}$} = 4.5^{+50} _{- 1.4} \,\, \mathrm{keV}$.
We find a weak ($3\sigma$) preference for WDM over $\Lambda$CDM, but both are statistically
consistent with the currently available data.

\item
We repeat our MCMC analysis, restricting to $\Lambda$CDM only but with a variable UVB. We find that the best-fit $\Lambda$CDM model
mainly differs from the WDM optimal model in that the IGM temperatures are slightly lower ($5-10$\%) for the WDM case. We find that both thermal histories are
in good agreement with the inference from \cite{gaikwad2020a} at $5.4 \lesssim z \lesssim 5.8$ and moderately higher than the temperatures from \cite{boera2019a} at
$4.2 \leq z \leq 5.0$.

\item We introduce the effect of a patchy reionization in our models by modifying \hbox{$P(k)$}\ from our uniform UVB simulations according to the
prescription presented in \cite{Molaro+2022}.
The likelihood distribution from our MCMC approach using the modified \hbox{$P(k)$}\ shows that the preference for a WDM cosmology is maintained
but the distribution shifts to higher values
of \hbox{$m_{\rm{WDM}}$} . The maximum likelihood and the 95\% lower limit constraint are $\hbox{$m_{\rm{WDM}}$}= 7.1 \, \mathrm{keV}$ and $\hbox{$m_{\rm{WDM}}$}= 3.8 \, \mathrm{keV}$, respectively.
Additionally,
the $\Lambda$CDM case is $2\sigma$ consistent with the best-fit WDM model when accounting for an inhomogeneous UVB. Notably, the different $\chi^2$ between the observed and best-fit \hbox{$P(k)$}\ model
is higher for the modified model to account for a nonuniform UVB, and we therefore use the likelihood distribution obtained from the uniform UVB models as the basis for our results.

\end{itemize}
\bigskip
\acknowledgments

This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by
the Office of Science of the U.S. Department of Energy under Contract DE-AC05-00OR22725, using Summit allocations AST169 and AST175.
An award of computer time was provided by the INCITE program, via project AST175.  We acknowledge use of the {\it lux} supercomputer at UC Santa Cruz, funded by NSF MRI grant AST1828315, and support from
NASA TCAN grant 80NSSC21K0271. B.V. is supported in part by the UC MEXUS-CONACyT doctoral fellowship. B.E.R. acknowledges
support from NASA contract NNG16PJ25C and grants 80NSSC18K0563 and 80NSSC22K0814. E.E.S. acknowledges support from NASA grant 80NSSC22K0720 and STScI grant HST-AR-16633.001-A. We wish to thank
Nick Gnedin and Avery Meiksin for many
useful inputs and valuable discussions.

redpajama_set_name: RedPajamaArXiv


text:
Eremobates formicarius es una especie de arácnido  del orden Solifugae de la familia Eremobatidae.

Distribución geográfica
Se encuentra en México.

Referencias

Formicarius
Arácnidos de México
Especies descritas en 1842
Fauna de México


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