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Jonathan & Charlotte: Station Sessions is Fabulous (Video)
I can't possibly write about how awesome it is being British and how wonderful so many British things are without mentioning the operatic duo, Jonathan and Charlotte.
Discovered on Britain's Got Talent earlier in the year, Jonathan Antoine and Charlotte Jaconelli are still in their late teens but are already famous as two of the most popular young opera singers in the world.
At the time they appeared on Britain's Got Talent the audience was not only blown away by their voices but also at how young they were, with Jonathan being only 16 and Charlotte just a year older.
Jonathan and Charlotte released their first album in the UK at the end of September, 2012. It went to number 5 on the British charts.
Jonathan and Charlotte's first performance on Britain's Got Talent is, of course, their most famous video, but I love this one — the Jonathan and Charlotte Station Sessions – where they sing live at St. Pancras International train station in November of this year.
By the way, the Station Sessions are wonderful events St. Pancras International Station puts on in seasons throughout the year to draw the public's attention to incredible music by allowing them to see performers live and, of course, free. Their website has a schedule of upcoming artists, as well as videos of some of the other British artists who have already sung there.
As for Jonathan and Charlotte, you can find out everything about them including their upcoming first national tour of the UK in 2013 on their website.
Park Bo Gum and IU starring in You Have Done Well as Ae Soon – a story about a rebellious woman and the man who loves her - January 27, 2023
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Has Talk Show Host Larry King Died? No, That Would Be Playwright Larry L. King
Sam Smith and Kim Petras' 'Unholy' was one of the spectacular songs played on the soundtrack of the series finale of Gossip Girl yesterday — Gossip Girl, Season 2, Episode…
Listen to Wesley Schultz's 'If It Makes You Happy' from How I Met Your Father, Season 2, Ep. 1


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AMV – Rainfall by Mastamind.
January 26, 2015 January 26, 2015 / razorbackwriteraus	/ Leave a comment
AMV – Anime music video. Another wonderful example of the beauty of anime mixed to the delights of an acoustic guitar and vocals. This is an art form that captures the imagination, and you find yourself swept away. This is by Mastamind, with the song "Wake me".
Holy Hell – SS.
Furious that the Ball was now in a state of utter chaos, the Princess decides to face the menace head on, but not without a bit of help – or interference. Continuation from Ballroom Blitz.
Scene setting – The Masquerade Ball of Greed, Seven Sins Series.
Co-written with Zetta, Temp, Nhal and Moo.
Zetta: His mask was taken off before he had gotten his answer, but Cecil was never impatient when it came to his love. When her hand lifted to remove his face-cover he rose his head up some so that it would be an effortlessly slip-off in place of a tugging. It was a light desire to be on the reverse end of this, however he was sure she would hit him, he was here representing Gabriel and had deliberately ignored the other princess. But he had only been ensuring his own lady's complacency and overall safety.
Cecil felt almost restless at this point, his arms were at his sides and he practically clawing at his own leggings. It was disgusting to see someone randomly approach a Prince, and in this case a Princess, that man- who had just come flying from the ceiling had no concern about rankings apparently. His pink-hair signified at least to a small desire that he wanted to be different, and this was the second time he had seen self-propelled flight. It was impossible to tell what type of strength that one had, but with his appearance he evidently thought very highly of himself. He did not even speak with any honorifics as one should when speaking to the upper class, the submissive guard had done so for so long he could not even fancy a different approach. Even now, giving his lady nicknames he maintains a strong sense of respect towards her. When she had spoke to him, asking if he would dare to question her his eyes spread widely. "I wouldn't! Princess, forgive me, with me here you need not lift a finger." He said, slightly flustered while turning from her, standing before her highness with his hand wrapped around the wrist of his other arm.
He cracked a light smile, perhaps his time would come soon.
The look on the assumed Princess' face was hilarious, lacking any sort of restraint, Blitz chuckled at the first sign of disdain shown. At first a strain of the neck, thinner than anything he could have named off the top of his head broadened in the light of the room. He was sure that once Anarchy Division was properly credited, he could easily use his senses in accordance with time-space to find the one person who had contact with all of those killed in the room. While obviously the large gathering of people would ensure that everyone touched at least five others here, none of them could have made it to several parts of the room while dancing.. Her verbal response would have made him laugh if he did not already release tension from his prior chuckle, she had continued, actually answering his questions instead of getting to the point. "Don't get hung up on the details, or something bad might happen, just say yes." He said simply, money was worthless to someone who could create. The man was more focused on getting fame after all, and deduced instantly that while they spoke, there was likely to be another murder. Infamy loved taking action in the midst of turmoil. Everyone had a singular focus right now, too. Then the worst possibility came to pass, an intruder on the conversation, just another presence to bide the killer more time to maneuver.
Unwilling to persist on a matter he previously didn't care for though, he listened to what the man had to say. He could tell though that this one was another VIP, the moment they'd come within feet of each other he was analyzed thoroughly. "You're pretty strong old man! Alright, show me what'cha got, just try to hurry." Or something bad might happen.. He didn't add that in, forsaking repetition. Black coated the ceiling first and moved to swiftly cover everywhere else, while the tactic seemed brilliant, someone like Eren would have laughed at the smokescreen provided for his teleportation. Blitz was prepared for something along those lines, so now that he had the darkness as a sort of cover as well he could work to prevent such a retreat, and if needed, his own instantaneous movement. Before anything else happened though, he heard the sound of fast moving metal, this moved at the same time as the shadows cloaked everywhere. Blitz shut his eyes, with no light in the room his other senses would become more dominant, his head was turned towards the assassin already while the body was hit and just about to hit the floor.
The murderer was bold, but from where he was Blitz was unable to tell his strength. That made it interesting, since the royalty seemed more eager to act than the surrounding guards, the demigod folded his arms he had always considered simply destroying the princes and conquer Hell on his own. Now that he had a decent gathering of what the two could do, he could now visually identify their capabilities. If he went on any type of offensive in a place like this he would bring down the castle in a few minutes, to that end he would wait for an opportunity to try and strike a critical blow.
Nhal: Belphegor shook his head slowly as the assassin revealed himself, upset at the fact that he had ruined what little fun the prince could have squeezed from the event. "What a waste… But I suppose it cannot be helped, feel free to destroy him princess, I shall keep these walls up for as long as I remained entertained by the battle. " drifting away from the center of the room Belphegor crossed his arms and watched carefully, observing both the combatants closely as he grumbled softly to himself.
Moo: The thudding of the bass from the music above was adding to the eerie feeling of the room. But it wasn't anything Kirsikka couldn't handle as she walked casually behind the hypnotized guard. She gave a light sigh while she looked along the dusty stone walls, cobwebs well gathered throughout the place. It was obvious someone had been through the area before though; a good sign as any. It was barely lit either, until they wound up in the room she'd been searching for. Her expression gave way to a small smile as she looked over the suit on its little showcase. The fact that the room was unguarded aside from the man in front of her was enough to raise suspicion…so her guard remained up as she gave the man a small push at his shoulder. He led her closer to the stand while she observed the statues around the room. So as she stopped in front of the suit, she put her hands on her hips and looked it up and down. "Do you speak? Or were those guards really insane…"
Gabriel felt more satisfaction than anything in seeing Cecil's eyes widen, the flustered expression showing plainly on his face before he turned away. "There is no forgiveness in Hell." She spoke casually while she stepped closer, her hand well on her little cane she'd created. Lydia had lost any bit of sensibility at this point, aside from understanding she didn't have to pay to find good help. Not that it was necessary. With the sound of someone's head being split in two, the entire crowd's attention would cast onto a single man. One who was apparently an outsider to hell, and not just the greed kingdom alone… his Holy armor and weaponry could be recognized by everyone. Even petty demons knew of the Excalibur. How the wielder of the sword had found his way here was what baffled anyone. Or why he chose to come. It actually pissed Gabriel off the instant she recognized him for a Templar. Her crimson hues widened while she bristled nearly as much as Lydia had. And at this rate… who cared if it was Lydia's problem, or if Gabriel wanted to see her party crumble to bits… This man was an idiot and the sight of his brilliant armor and equipment just struck her nerves. She began to lift her cane as though it were her sword, as she could actually turn it into such in a blink…but she paused and forced herself to lower it with an exhale. Even as she glared, she knew better than to jump into the middle. Otherwise she might kill more than just the Templar, and nobody needed the trouble Lydia could reap if she so wished. Plus, Gabriel was still a man, and still needed to be changed back. It didn't stop her glaring eyes from watching the scene play out, anticipating blood to spray from either party.
Astarte hadn't had anything to do this entire time. The situation had become dire…and the way the princess had reacted to Blitz wasn't exactly the most positive. She really did palm her face this time while Lydia's voice echoed around the room, repeating something about payment. This woman was definitely full of dramatics, but Blitz certainly wasn't caring any. Did her ears really pick up a chuckle from him. It brought a small grin to her lips… But now as the prince was offering a helping hand, everything was just lost. Not that it would have mattered…the culprit made himself known as he pulled his blade free and stuck it into some demon's head, yanking it free before revealing himself. This was the part where the room was filled with gasps, everyone basically recognizing his holy armor and especially Excalibur. Astarte herself was a demon, just like everyone else in the room. Besides one person. She looked at Blitz while he observed the scene, the princess having gotten completely pissed that she attacked the intruder herself. Would he jump in?
Temp: There were a great deal of frightened faces surrounding William. The demons were obviously confused as to how and why someone like him was here. The fact that he carried Excalibur was probably the main cause of panic though. Almost everything in this room was very vulnerable to the holy blade, as well as William himself. The demons closest to him were all on their knees simply due to the aura that he was emanating. There was clear aggression within the room, mostly coming from the royalty, but that was to be expected. Obviously, this event had been a big deal to the Kingdom of Greed, and he had single-handedly ruined it. Honestly, he had expected more demons to be foolish and straight up attack up, but instead of many there was only one. The Princess of Greed was obviously furious, and decided to start attacking him. Her fire-ball was quickly blocked by Sanctus, which he had pulled up to block with. His grip on both sword and shield tightened as he turned his head to look at the area around him. Guards would likely attack soon, and with them anyone else that felt bold enough to confront him. No matter what these demons may have thought, he wasn't after a single one of them. All of his targets that were among the attendees of this party were already dead. The only thing William intended to do at this point was to leave this place. "Not Target…No Conflict…Fighting Foolish." The awkward broken words were spoken loud enough for everyone to hear, though he had a feeling they would do little for him. Demons were never quick to lower their aggression, and he wastechnically one of their greatest enemies. Regardless, he actually turned his back on the people in the room and began making his way towards the nearest exit. Just because his back was turned didn't mean he was vulnerable though. He was actually very much anticipating a violent reaction. Quite honestly, he'd prefer to leave this place without shedding any more blood.
Razorbackwriter: Scores of the party guests, the elite members of hell closest to the assassin were on their knees – bedazzled and stricken by the force of the holy sword's power. Held tightly in the grip of William's hand he was a danger to all present, and dressed for war as opposed to a society ball. Lydia's attempt to knock the blade clean from the assassin's hand was foiled by the skilled wielding of the Templar. The Princess of Greed lowered her charged hand slowly, as she realized that this mode of attack was useless against him. Lydia's lips puckered and with narrowing eyes she heard the assassin exclaim in a broken voice that she was not the target, and that he had no intent to cause conflict with her directly. Fighting him, was in his mind a foolish action.
Easy for him to say, when your reputation amongst the Princes of Hell was at stake. Already the Prince of Sloth had told Lydia to finish him, and while Gabriel looked deeply annoyed by the Templar's presence he or she made no move to enter what was Lydia's fight.
"Don't you dare turn your back on me, you coward." The Princess's voice was filled with a bravado and a sense of pride. She was still the Princess of Ambition, and did not want to lose her place in Hell. If others saw her as weak, and backing out of a fight, then they may well try to remove her and destroy Greed entirely. A low and guttural growl emitted from the very pit of her stomach as she took a single step forward. Her darkened locks loosening from the delicate binding to form a windswept frame around her face. A quick glance upward as the Templar had his back to her and she saw the massive chandelier that was lit and hanging over head. If she could not make a direct hit upon him with her powers, then maybe it would take something a little bigger. Lydia closed her eyes, as she willed the yoke of the damned. The walls of the ballroom shimmered with a greenish glow as many hands slid out from the walls, and veered upward….higher and higher till reaching the chandelier. The metal screws that held the chandelier in place, whizzed at great speed, till the only thing holding the chandelier up was one small bolt. It swayed back and forth precariously, right over the Templar's head.
"There will be no escape for you!" At the final word spoken, the chandelier plummeted from the roof heading straight for the Templar as the Princess bore a broad grin. So, she was about to lose a precious and dazzling ornament, but knocking the Templar out from above would more than compensate that.

redpajama_set_name: RedPajamaCommonCrawl


The amazing Cirque u Soleil bring their ice show Crystal to Kingston from July 3rd to July 7th. This is a one of a kind show that blends their circus act with the world of ice skating.
Wednesday, July 3 at 7:30 p.m.
Saturday, July 6 at 4:00 p.m. and 7:30 p.m.
Sunday, July 7 at 1:30 p.m. and 5:00 p.m.


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1 critical after Las Vegas crash involving suspected DUI driver
Metropolitan Police Department officers responded to a crash in the south Las Vegas Valley that injured two people early Tuesday morning.
By Jessica Terrones Las Vegas Review-Journal
Updated March 5, 2019 - 9:10 am
Las Vegas police investigate a crash on Las Vegas Boulevard South near Robindale Road, Tuesday, March 5, 2019. Two people were injured and taken to a hospital. (@LVMPD_Traffic/Twitter))
Officers responded to the crash at East Robindale Road and Las Vegas Boulevard South at about 3:15 a.m., Metro Lt. David Gordon said.
A Ford Mustang traveling north on Las Vegas Boulevard and crashed into the side of a semi-trailer that was making a right turn from Robindale Road, Gordon said.
Both the driver and passenger of the Mustang were taken to the hospital. The passenger was in critical condition and "fighting for their life" according to a Tweet posted by Metro. The driver is being booked into the Clark County Detention Center for suspected impaired driving, the Tweet said.
No further information was immediately available.
Contact Jessica Terrones at jerrones@reviewjournal.com or 702-383-0256. Follow @JessATerrones on Twitter.


A good web designer uses strategic use of color, which is important for website development. A website's color palette should be aesthetically pleasing to viewers, should not be discordant, should have contrast where appropriate, and should complement the branding or logo of the business.
The Design Tip of the Day is brought to you by Bigwig Monster Media. BGWG is a full-service brand experience design agency, specializing in experiential and intuitive web design in the greater Los Angeles area.


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Q: Approval process within a VF page in lightning experience does not work I have a VisualForce page working fine in SF Classic that contains the approval process related list with this code:
<apex:relatedList list="ProcessSteps" pageSize="3" />

When I switch to lightning experience, the history still displays I have several issues:

*

*When clicking "Recall Approval Request" I get a dialog with title "Edit Approval request", I cannot edit anything on that dialog and when I hit "Save & New" I get the following error:

*I get exactly the same as in 1. when hitting the button "Reassign"

*When hitting "Approve / Reject" a new tab opens with the page /p/process/ProcessInstanceWorkitemWizardStageManager (in Classic I see the page in the same tab). In that page the buttons "Back to [Object]: [id]", "Cancel", "Approve", "Reject" don't redirect me back to the object, I get the js error in the console:

Failed to execute 'postMessage' on 'DOMWindow': The target origin
  provided ('[my_org].lightning.force.com') does not match the recipient
  window's origin ('[my_org].my.salesforce.com').

Is there a different way to include the approval history and these buttons in a VS page when running in Lightning Experience or should we implement a custom list with custom buttons to approve, reject, reassign, submit for approval and recall since this is not supported in Lightning? Thanks

A: Since you already know it's not supported in Lightning, your code should be written such that it's context sensitive. You can use code such as what's contained in this Trailhead Module on multipurpose pages to write code that adapts behavior depending on whether you're in LEX or Classic. In that way you can use the standard related list in Classic, then use the custom list approach you've mentioned when in LEX.

redpajama_set_name: RedPajamaStackExchange


— When we talk about environmental and social problems, we rarely mention population growth. We'll bemoan the shortage of affordable housing, the number of cars on the road, and the loss of topsoil to marginal agriculture. We emphasize how each person can make a difference by reducing consumption, but rarely do we consider that most of our problems are multiplied as we continue to add more people to the world.
Why Population is a problem?
The multiplying effect is why population is an environmental problem. If we could support 6.1 billion people in 2001 with the same quantity of resources we used to support 1 billion in 1800, we'd be in great shape! But since we can't, the continual addition of passengers to Spaceship Earth means we need more food, more clean water and more fuel every year – even though our resources are limited.
For millions of years of human history, there were only a few million of us on the planet. According to the estimates of the United Nations Population Division by the time the world reached its first half-billion in 1500, the growth rate was already accelerating (www.un.org/popin). In 1800, the world had a billion people for the first time ever. By 1930 the population doubled again to 2 billion, and new tools like vaccines to further cut the death rate.
In 1960, the population reached 3 billion. For the first time, population doubled within living memory, up from 1.5 billion in 1900. But that was nothing – when we reached 6 billion in 1999, we had not only doubled the population in a mere 39 years, we had quadrupled it in 100 years! A centenarian alive today has seen the population double TWICE in his or her lifetime.
Our rate of increase is beginning to slow at last. But unless we take further action, world population will still balloon to over 9 billion by 2060. Every country except the United States has a plan to slow its growth. However, many of these plans rely on funding that the U.S. promised – and now withholds! Although population growth is a problem worldwide, it will only be solved locally by each country. It is imperative that all of us do our part.
Our growth rate in the U.S. is the highest in the developed world, due mostly to our extremely high immigration rate. Since our environmental impact is a function of consumption habits as well as numbers, we have more impact on resource depletion and pollution than any other nation on the planet! In terms of impact, the U.N. Population Division reports that the United States is the most overpopulated country in the world. For example, the average American uses as much energy as 18 Chinese people, 34 Indians, or 526 Ethiopians. This is unsustainable. We cannot continue consuming resources at these rates.
In Minnesota, our only hope for sustainable transit, housing, and environmental solutions is a stabilization of our local population. Yet most politicians, businesses, and nonprofits continue to press for more growth, or they assume growth is inevitable. The challenge is one of education.
1. Have fewer children, and support family planning so that other families can choose to have fewer children.
2. Contact your local officials and state legislators and educate them about the impact of local population growth on such issues as sprawl, affordable housing, public transit, unemployment, and school funding.
3. Contact your representatives at Congress and educate them about global and national population growth and its connection to such issues as immigration, fuel prices, pollution, and quality of life.
4. Write to newspapers, magazines, and broadcasters. Encourage them to clearly make the link in all of their stories that population growth is a major factor driving all other major issues.
5. Encourage your place of worship, school, college, club or other organization to arrange a presentation by World Population Balance.


^ Slow progress on capability growth. Defence Review Asia.com. 2011-11-22 [2014-12-04].
^ Anda, Redempto. Government told of China buildup 2 months ago. Philippine Inquirer. 2012-07-17 [2013-10-29].
^ 高俊国,刘宝银. 《南沙群岛空间融合信息分析与示警:群礁发育、军事区位、警示系统》. 海洋出版社. 2009: 2–3页. ISBN 9787502773083.
^ 刘石磊、陈勇、荣启涵. 菲越长期进行非法"造岛"活动. 新华社. 2001-04-28 [2019-01-05] (中文(中国大陆)).
^ 王冠雄. 中國大陸填海造陸工程之戰略安全面探討 (PDF). 國立臺灣師範大學. 2001-04-28 [2019-01-05] (中文(台灣)).


The NXS Momentum Cross-Asset Index is a dynamic multi-asset portfolio that aims to target consistent returns throughout the market cycles. The Index, also known as the MOXA Index, has been launched by Natixis in December 2016. The historical performance of the Index is available on Bloomberg and the Natixis NXS index website.
Natixis offers a robust and transparent portfolio construction with a rule-based index based on three principles: Diversification, Momentum and Risk Management.
– Diversification : The index allocates in futures contracts across three asset classes (Equities, Fixed Income and Commodities) and three regions (Europe, US and Japan).
– Momentum : The dynamic allocation framework gets exposure to the best performers. It allows the index to benefit from an upside trend and market turnarounds.
– Risk Management : The index is monitored to target a reasonable and predefined level of volatility (5%) using a portfolio weighting technique that allows to attribute the same level of risk to each component.
Investors are looking for yield but also to avoid highly volatile investments. Multi-asset investing, also called cross-asset allocation, is typically seen as an effective way to use diversification as a source of long-term performance with reduced risks.
Momentum is used as the empirical evidence from the academic literature on the subject shows that financial assets that have appreciated in the past tend to continue to follow a bullish trend, thanks to the presence of a behavioural bias that call into question the theory of market efficiency.
The Natixis MOXA index uses a Risk Management mechanism that divides equally the portfolio risk across the 6 components of the Momentum Selection. The Risk Management principle is that each component has the same contribution to the portfolio risk (taking into account volatility and correlations). It aims to reduces the risk concentration bias of a portfolio, and generates risk-return outperformance (compared to more traditional strategies).


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Ardisia coarcta är en viveväxtart som beskrevs av Benjamin Clemens Masterman Stone. Ardisia coarcta ingår i släktet Ardisia och familjen viveväxter. Inga underarter finns listade i Catalogue of Life.

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redpajama_set_name: RedPajamaWikipedia


text:
\section{Introduction}
\label{intro}

Accretion of matter onto a gravitating centre is a ubiquitous physical process in astrophysics. The matter gravitationally captured from the surrounding rarefied medium by a body of mass $M$ (or, if in a binary system, escaping from the secondary star as a stellar wind or due to Roche lobe overflow) eventually reaches the surface of the body with the velocity of the order of the parabolic one, $v=\sqrt{2GM/R}$, where $R$ is the radius of the body. This velocity becomes very high in the case of accretion onto a compact star.
For neutron stars with radius $R_{NS}\sim 10~\mbox{km}$ the velocity reaches $\sim 10^{10}~\mbox{\rm cm~s$^{-1}$}$, so that the accretion energy release
is $L\sim 0.1 \dot Mc^2$, where $\dot M$ is the mass accretion rate and $c$ is the velocity of light. These basic facts required the calculation of the accreting matter braking near the compact star surface. In the pioneer work by
\cite{1969SvA....13..175Z}, the structure of the shock wave produced by
spherically symmetric accreting matter near the neutron star surface without magnetic field was calculated. Braking of the accreting matter was assumed to be primarily due to Coulomb interactions of the infalling protons with the surface, which is justified at low accretion rates when interaction of the charged particles with radiation is insignificant.

\begin{figure*}
\center{\includegraphics[width=0.9\textwidth]{6sources.pdf}}
\caption{The ratio of the fluxes in 5--12\,keV and 1.33--3\,keV ranges
  (referred to as ``hardness ratio'' in text) measured with RXTE/ASM for
  six transient accreting pulsars as a function of the total ASM flux in the
  1.33--12\,keV range.
}
\label{f:hardness}
\end{figure*}

Immediately after the discovery of X-ray pulsars in 1971 \citep{1971ApJ...167L..67G} it was realized that in bright pulsars the radiation plays a crucial role in braking of the accreting matter onto the surface of a neutron star with strong magnetic field. Indeed, in this case the matter is canalized by the neutron star magnetic field onto the magnetic polar caps, which are characterized by a small radius $r_0\approx R_{NS}\sqrt{R_{NS}/R_A}\sim 10^5$~cm (for a purely dipole field), where $R_A$
is the magnetosphere radius.

It is now well recognized that once the radiation density above the polar cap
starts playing the role in the accreting matter dynamics, an optically thick
accretion column above the polar cap is formed \citep{BaskoSunyaev76} (see \cite{2015MNRAS.447.1847M}
for the latest investigation). The characteristic height of the column increases with accretion rate,
most of the emission escapes through sidewalls,
and it can be expected that above some X-ray luminosity the dependence of the observed properties
of the continuum emission on the X-ray luminosity can become different from
that in the low-luminosity regime.

Here we stress that the effects of the strong magnetic field
are important for the observed properties of X-ray continuum at energies
below the cyclotron line energy due to
scattering processes which have different cross-sections for different photon
polarization modes.
At small accretion rates, the accretion mound can be viewed as a thin slab, and
mostly ordinary photons (for which the electron scattering cross-section
is strongly angular dependent but frequency independent) escape along the magnetic field lines forming
a pencil-beam X-ray emission diagram \citep{1975A&A....42..311B}. In contrast, when
the accretion column is formed at higher X-ray luminosities, mostly extraordinary photons
(for which the electron scattering cross-section is angle independent but strongly frequency dependent)
escape sidewall to form a fan-like X-ray emission beam \citep{1986Ap.....25..577L}.

Presently, there is a wealth of observational data on X-ray pulsars
that can be used to check different regimes of accretion onto
magnetized neutron stars.
Different types of spectrum--luminosity dependence were first
discovered based on the behavior of cyclotron resonant scattering
features (CRSFs) (e.g. \cite{2006MNRAS.371...19T, 2007A&A...465L..25S, Klochkov:etal:11, Becker_ea12, 2014ApJ...781...30N}).

However, the mechanism of the CRSF generation in accretion columns
of accreting neutron stars is still not well understood due
to a very complicated physics of radiation transfer in super-strong
magnetic fields of neutron stars.
For example, recently a novel model for CRSF production
in spectra of bright X-ray pulsars due to
reflection of the radiation generated in the accretion column
from the neutron star surface was proposed \citep{2013ApJ...777..115P}. This model
can successively explain the CRSF energy dependence on luminosity observed
in outbursts of the transient X-ray pulsar V~0332+53 (see also \citep{2015MNRAS.448.2175L} for further
applications of the model).
From the observational
point of view, the study of CRSFs is a challenging task because it requires long
dedicated observations using the instruments with high effective area
and spectral resolution above 20--30\,keV. Only in a fraction of
accreting pulsars CRSFs are reliably measured \citep{2012MmSAI..83..230C, 2014SSRv..tmp...58R}.

Recently, \cite{Klochkov:etal:11} and \cite{Reig:Nespoli:13}
pointed out that
in addition to the CRSF behaviour,
different types of the spectrum--luminosity dependence
in accreting pulsars can be probed by studying the variability of the X-ray
continuum with luminosity.
Specifically,
it was found that the X-ray continuum
described by a power-law dependence $F_\mathrm{X}\sim E^\Gamma$ becomes \textit{harder} with
increasing X-ray flux in X-ray pulsars showing a \textit{positive} correlation of
the CRSF energy $E_c$ with flux,
whereas it becomes \textit{softer} or virtually does not change with increasing flux
in pulsars showing a negative $E_c(F_\mathrm{X})$-correlation
(Figs.\,3 and 6 in \cite{Klochkov:etal:11}). Clearly, the continuum studies
are much less demanding from the point of view of data analysis than the spectroscopic
analysis of the CRSF behaviour (if the CRSF is reliably identified in the
X-ray pulsar spectrum at all).

The purpose of the present paper is to perform model 2D calculations of
the accretion column structure in the radiation diffusion approximation
and to calculate the emerging X-ray continuum
in order to see how
the hardness of the sidewall emission
from accretion columns with different geometries (a
filled or hollow cylinder) changes with
accretion rate variations in the regime of radiation-dominated
accretion flow braking. We calculate the sidewall energy flux escaping
from the optically thick accretion column and the saturated Compton
spectrum of extraordinary photons. We find that
for typical parameters of X-ray pulsars (the neutron star surface
magnetic field $B= 3\times 10^{12}$~G, mass accretion rate onto one pole
$\dot M=(1-12)\times 10^{17}$~g~s$^{-1}$), with increasing mass accretion rate the hardness of
the emergent sidewall emission from the column always increases.
The sidewall emission from the column is Doppler-boosted by unbraked
matter in the external part of the column toward the neutron star surface.
The reflected radiation
from the neutron star atmosphere calculated in the single-scattering approximation
is harder than the incident emission, and its addition to the
total flux form the column renders the spectrum even harder.
However, starting from some accretion rate the height of the column
increases such that the fraction of the reflected radiation in the
total flux starts decreasing. This purely geometrical effect
leads to the saturation of the hardness ratio
at $\dot M_{cr}\sim (6-8)\times 10^{17}$~g~s$^{-1}$ (for the assumed neutron star
parameters).
In the case of the hollow-cylinder accretion column geometry, the saturation
of the spectral hardness has not been reached in the calculated range of
mass accretion rates due to smaller photon diffusion times across the
columns thickness and correspondingly smaller heights of such columns, when
the contribution of the emission reflected from the neutron star surface
always dominates.

The structure
of the paper is as follows.
In Section \ref{s:obs} we briefly describe
the observed correlations of CRSF with X-ray flux and X-ray continuum
properties with X-ray flux. In Section \ref{s:geom} the basic
equations of the structure of
the radiation-supported columns
and their numerical solution are described. The results of
calculations of the spectrum are presented in Section \ref{s:spectrum}, which is followed by the
summary and conclusions.

\section{Observations}
\label{s:obs}

There is a growing number of X-ray pulsars showing
the dependence of $E_c$ of their X-ray flux (e.g., \cite{Becker_ea12}
and references therein).
The cyclotron energy $E_c$ in the bright transient X-ray pulsar
V\,0332+53 decreases with luminosity $L_{\rm X}$
\citep{2006MNRAS.371...19T, 2010MNRAS.401.1628T}.
A similar negative $E_c(L_{\rm X})$-correlation has been reported for
another bright transient pulsar 4U\,0115+63 \citep{2007AstL...33..368T, 2004ApJ...610..390M}.
Recently, however, this correlation has been questioned by
\cite{2013A&A...551A...6M}, who argued
that the $E_c(L_{\rm X})$-correlation in 4U\,0115+63 is an artefact
related to the continuum modelling (see also \cite{2013AstL...39..375B}
for an independent analysis).

There is another type of X-ray pulsars with lower X-ray luminosities
and somewhat higher magnetic
fields which exhibit a \emph{positive} correlation of $E_c$ with $L_{\rm X}$:
Her X-1 \citep{2007A&A...465L..25S}, GX\,304$-$1 \citep{2011PASJ...63S.751Y, 2012A&A...542L..28K},
and probably Vela X$-$1 \citep{2014ApJ...780..133F}
and A\,0535+26 \citep{Klochkov:etal:11, 2013A&A...551A...6M}.

As mentioned in the Introduction, a similar
bimodality is observed in the dependence
of the X-ray continuum hardness on luminosity. This dependence can be studied using,
for example, data from all-sky monitors such as RXTE/ASM and MAXI, i.e. without dedicated
spectroscopic observations which are necessary to measure
CRSFs. Following this approach, we measured the hardness ratio as a
function of luminosity in the accreting
pulsars GX\,304$-$1, 4U\,0115+63, V\,0332+53, EXO\,2030+375, A\,0535+26
and  MXB\,0656−072
using the data from different energy bands of RXTE/ASM. The result
is shown in Fig.\,\ref{f:hardness}.  To convert the ASM count rates into X-ray
luminosities, we used published distances to the sources
(GX\,304$-$1: $\sim$2\,kpc, \citealt{Parkes:etal:80}; 4U\,0115+63: $\sim$7\,kpc,
 \citealt{Negueruela:Okazaki:01}, V\,0332+53: $\sim$7\,kpc,
  \citealt{Negueruela:etal:99}; EXO\,2030+375: $\sim$7\,kpc,
  \citealt{Wilson:etal:02}; A\,0535+26: $\sim 2$~kpc,
\citealt{1998MNRAS.297L...5S}; MXB\,0656-072: $\sim 3.9$~kpc,
\citealt{2006A&A...451..267M})
  and their broadband X-ray spectra from the archival pointed
  observations with INTEGRAL and RXTE available to us.
One can see that at lower fluxes
  the hardness ratio increases with flux. At a certain flux, however, a
  flattening of the hardness ratio is observed in
  4U\,0115+63, V\,0332+53, EXO\,2030+375, A\,0535+26
and  MXB\,0656−072. This `turnover'
  occurs at the flux roughly corresponding luminosities $(3-7)\times 10^{37}$\,erg s$^{-1}$. In GX\,304$-$1,
  which does not show such a turnover, this
  `critical' luminosity
  has simply not been reached during the outbursts registered by RXTE ASM.

A similar dependence of spectral properties on the X-ray flux at luminosities below
$\sim 10^{37}$~erg~s$^{-1}$ was also reported from spectroscopic observations
of the transient Be-X-ray pulsar GRO J1008-57 \cite{2014EPJWC..6406003K}.

At the lowest energies covered by RXTE/ASM, the spectrum of accreting
pulsars is significantly affected by photo-electric absorption caused
mostly by matter in the vicinity of the source. Such an absorption
naturally influences the derived hardness ratios and cannot be
accounted for without a high-resolution spectral analysis using pointed
observations. Neutral absorbing matter surrounding the
accretor might correlate with the mass transfer rate in the binary and
might therefore be proportional to the X-ray luminosity of the pulsar.
Such an effect might at least contribute to the observed positive correlation
between the hardness ratio and flux. However, we do not expect any
break in the slope of the correlation between the absorption column
density and flux at $L_{\rm X}\sim 10^{37}$~erg s$^{-1}$ (although we cannot
exclude this possibility). We therefore identify the observed breaks
with those reported by \cite{Reig:Nespoli:13} at similar X-ray luminosities
based on the data from RXTE/PCA observations taken at
higher energies which should be unaffected by the photo-electric absorption.

\section{Accretion column structure in the radiation diffusion limit}
\label{s:geom}

\subsection{Qualitative considerations}

At high luminosities, $L_{\rm X}\gtrsim 10^{37}$~erg~s$^{-1}$, the radiation pressure dominates,
and the braking of the accreting matter flow is due to interaction with photons. In this case,
the kinetic energy of falling particles $m_pv_0^2/2$, where $v_0=10^{10}$~cm s$^{-1}$ is the free-fall velocity near the NS surface, decreases by almost 99\% at optical depths
$\tau\sim (2-3)(c/v_0)\sim 4-9$. This was shown for the first time by \cite{1973NPhS..246....1D},
and in a wide range of parameters was calculated by \cite{1981A&A....93..255W}
by solving two-dimensional
gas-dynamic equations with diffusive radiation transfer.   As a result, the shape of
the zone of energy release looks like a 'mound' with the characteristic height $z_0\sim r_0$.

With further increasing X-ray luminosity above $L_{\rm X}>L^*$,
as was first shown by \cite{BaskoSunyaev76},
the height of the braking zone starts increasing, and instead of
a 'mound' an optically thick accretion column appears with $z_0>r_0$.
Most of the
kinetic energy of the accreting flow is transformed into heat
at around $z_0$ (which sometimes is referred to as the
height of the radiation-dominated shock), and below this height the matter settles down
towards the column base. The thermal energy is advected by the settling matter with
an effective velocity of $v\sim 0.1 v_0$, and the generated heat
finally escapes through the column sidewalls.

It is possible to estimate the critical luminosity $L^*$ by equating the
dynamical time of the fall of matter
to the diffusion time of photons across the column.
The characteristic settling time is
clearly
$t_s=z_0/v$. The characteristic time of the radiation diffusion across the
filled cylinder column is
\beq{tdif}
t_d\simeq \frac{r_0^2}{\nu_d}\simeq \frac{r_0^2\varkappa_\perp}{c}\rho=\frac{r_0^2\varkappa_\perp}{c}\frac{S}{v}
\end{equation}
where we have eliminated the density $\rho$ using the mass continuity equation
\beq{e:cont}
S=\rho v=\frac{\dot M}{\piup r_0^2}\,.
\end{equation}
In the case of a hollow cylinder with wall thickness $br_0$ the diffusion time decreases
with $b$:
\beq{tdif_hollow}
t_d\simeq \frac{b^2r_0^2}{\nu_d}\simeq \frac{b^2r_0^2\varkappa_\perp}{c}\rho=\frac{b^2r_0^2\varkappa_\perp}{c}\frac{S}{v}=\frac{b\varkappa_\perp}{c}\frac{\dot M}{\piup v}
\end{equation}
By equating $t_s=t_d$ and noting that the velocity is crossed out, we arrive at
the expression
\beq{}
z_{0,f}=\frac{\varkappa_\perp}{\piup c}\dot M\,,\quad z_{0,h}=\frac{b\varkappa_\perp}{\piup c}\dot M\,
\end{equation}
for the filled and hollow cylinder geometries, respectively.

Now, by equating $z_0=r_0$, we find the critical mass accretion rate $\dot M^*$
and the corresponding X-ray luminosity
\beq{L*}
L^*=0.1 \dot M^* c^2=
\frac{\piup c}{b\varkappa_\perp}0.1 c^2 r_0\approx 2.36\times 10^{36}[\mathrm{erg\, s}^{-1}]
\myfrac{r_0}{10^5\hbox{cm}}\myfrac{b\varkappa_\perp}{\varkappa_T}^{-1}.
\end{equation}
Here the factor $b$ should be set one for the filled cylinder geometry.

It is important to realize that
the accurate value of $L^*$ should be found from two-dimensional numerical
calculations of the radiation transfer equations, and, for example, \cite{1981A&A....93..255W} found
\beq{L*wang}
L^*\approx 5.25\times 10^{36}[\mathrm{erg\, s}^{-1}]\myfrac{E_c}{\bar E}^{2/5}\myfrac{r_0}{10^5\hbox{cm}}\myfrac{M}{1.5 M_\odot}
\end{equation}
Here the factor $(E_c/\bar E)$ takes into account the effective change in the
photon scattering cross-section in the strong magnetic field and the deviation of the magnetic
field line geometry from the simple cylindrical case near the NS surface. This factor is $\sim 1$ if
the mean photon energy $\bar E>E_c$. It is seen that our simple estimate \Eq{L*} derived
above is consistent with this value to within a factor of two.
Recently, the critical luminosity was reassessed by \cite{2015MNRAS.447.1847M}
who found it to vary by almost an order of magnitude (depending on the magnetic field)
within an interval centred at
$\sim 10^{37}$~ erg~s$^{-1}$.

Therefore, the qualitative considerations presented above suggest the increase
in the accretion structure height $z_0\propto \dot M$ above some critical
luminosity $\sim 10^{37}$~ erg s$^{-1}$
(see also a more detailed derivation in \cite{1992ApJ...388..561A}, Section 3.).

\subsection{Numerical simulations of axially symmetric accretion column}

Qualitative considerations described above can be made more precise by numerical calculations of steady-state accretion columns. This radiation-hydrodynamic problem, complicated by the need to calculate the radiation transfer in a strong magnetic field, has not been solved self-consistently as yet. However, the structure of an optically thick accretion column at luminosities above $10^{37}$~erg~s$^{-1}$ can be calculated in the radiation diffusion approximation with grey scattering coefficients along and perpendicular to the magnetic field lines \citep{1973NPhS..246....1D, BaskoSunyaev76, 1981A&A....93..255W}. The emergent radiation spectrum will be formed due to scattering of photons on electrons in the optically thin outer layers, which is a separate problem (see the next Section).

We shall consider two possible axially symmetric geometries of accretion columns: a filled cylinder of radius $r_0$
and a hollow cylinder of the inner radius $r_0$ and thickness $br_0$.
In both cases $r_0$ is determined by the magnetosphere radius $R_A$, and in the second case the wall thickness $br_0$ can be related to the distance the disc matter enters the magnetosphere before being completely frozen into the magnetic field. We shall assume a purely dipole magnetic field and the disc matter frozen at a fixed fraction of the Alfv\'en radius.

From the definition of the Alfv\'en radius, $R_A \propto {\dot M}^{-\frac{2}{7}}$, and the expression for the polar cap radius $r_0$ we see that the polar cap radius scales with accretion rate as $r_0 \propto {\dot M}^{\frac{1}{7}}$.
The freezing depth of disc plasma at the Alfv\'en radius is fixed as $\Delta = 0.1 R_A$, and since $\frac{\Delta}{R_A} = b$ we have $b \simeq  0.1$. This means that with changing mass accretion rate the thickness of the accretion wall in the case of hollow cylinder geometry changes as
$br_0\propto{\dot M}^{\frac{1}{7}}$ \footnote{In principle, one may consider further complications, e.g., using a specific model of the magnetosphere-disc coupling, like it was done in \cite{2015MNRAS.447.1847M}. This only slightly changes the dependence of $br_0$ on $\dot M$.}.

Note that the value of $b$ is difficult to calculate precisely; it is clear that it should depend on many factors, including the
NS magnetic field axis misalignment, the details of the matter
entering the magnetosphere due to various instabilities, etc., which are beyond the
scope of the present study. However, we should note that in the case of thin cylinder wall, $ b\ll 1$, the radiation diffusion time \Eq{tdif} is proportional $t_d\propto b$, thus decreasing the height of the column $z_0$ at a given mass accretion rate $\dot M$. This effect is confirmed by our calculations (see below).
The neutron star magnetic field is assumed to be homogeneous across the column. This approximation is justified for not very high accretion heights (especially in the case of the hollow cylinder geometry).

\begin{figure*}
\begin{multicols}{2}
\includegraphics[height=0.4\textwidth]{rm1_r.pdf}\\a)
\vfill
\includegraphics[height=0.4\textwidth]{rm5_r.pdf}\\b)
\end{multicols}
\hfill
\begin{multicols}{2}
\includegraphics[height=0.4\textwidth]{m1_r.pdf}\\c)
\vfill
\includegraphics[height=0.4\textwidth]{m5_r.pdf}\\d)
\end{multicols}
\label{f:structure}
\caption{Contours of constant $Q$ (0.9 to 0.1, from top to bottom).
Top panels: the hollow cylinder geometry with $b=0.1$ calculated for
$\dot M_{17}=1$ (a) and $\dot M_{17}=5$ (b).
Bottom panels: the filled cylinder geometry
for $\dot M_{17}=1$ (c) and $\dot M_{17}=5$ (d).
}
\label{f:Q}
\end{figure*}

\subsubsection{Boundary conditions}

We are working in cylindrical coordinates $r,\varphi,z$ centred at the columns
axis and $z=0$ at the neutron star surface.
The initial velocity of the falling matter at high altitude above the surface of the neutron star is $v_0=10^{10}~\mbox{\rm cm~s$^{-1}$}$. At the cylinder base ($z=0$), the velocity is $v=0$. As a boundary condition at the column side surface we used the
relation between the radial energy flux to the energy density $U$ in the form $F_r(r_0,z)=2cU(r_0,z)/3$, which roughly corresponds to the conditions expected in the scattering
atmospheres in the Eddington approximation.

\subsubsection{Basic equations}

The cylindrical symmetry of the problem makes it essentially two-dimensional.
The steady-state momentum equation (ignoring gravity, which is very good approximation as discussed e. g. in \cite{BaskoSunyaev76}) for accretion braking by the radiation with energy density $U$ reads
\beq{e:momentum}
  \left(\mathbf{S}\cdot\nabla\right)\mathbf{v}=-\frac{1}{3}\nabla U,
\end{equation}
where $\bm{S}=\rho\mathbf{v}= \mbox{const}$ is the mass continuity equation. The integration of these equation yields
\beq{e:r-density}
U=3S(v_0-v).
\end{equation}

Following \cite{1973NPhS..246....1D}, the energy equation can be written as
\beq{e:energy}
\nabla\cdot\mathbf{F}=-\mathbf{S}\cdot\nabla\left(\frac{v^2}{2}\right),
\end{equation}
where we has neglected the flow of internal energy of the falling matter.

The radiative transfer equation in the diffusion approximation is
\beq{e:transfer}
\mathbf{F} = -\frac{c}{3\varkappa\rho}\nabla U+\frac{4}{3}U\mathbf{v},
\end{equation}
where the inflow of gas is considered to be stationary.

From equation (\ref{e:transfer}) in cylindrical coordinates we find the components of the radiation energy flux:
\beq{e:Fr}
F_r=\frac{-\frac{c}{3\varkappa_\bot\rho}\frac{\partial U}{\partial r}}
{1+\frac{1}{3\varkappa_\bot\rho}\frac{1}{U}\left|\frac{\partial U}{\partial r}\right|},
\end{equation}
\beq{e:Fz}
F_z=\frac{-\frac{c}{3\varkappa_\|\rho}\frac{\partial U}{\partial z}-\frac{4}{3}Uv}
{1+\frac{1}{3\varkappa_\|\rho}\frac{1}{U}\left|\frac{\partial U}{\partial z}\right|}.
\end{equation}
where the coefficients $\left(1+\frac{1}{3\varkappa_\bot\rho}\frac{1}{U}\left|\frac{\partial U}{\partial r}\right|\right)^{-1}$ and $\left(1+\frac{1}{3\varkappa_\|\rho}\frac{1}{U}\left|\frac{\partial U}{\partial z}\right|\right)^{-1}$
are introduced to use the modified diffusion approximation in the optically thin regions where the change of the radiation energy density on the photon mean free path becomes significant (see  \cite{1981A&A....93..255W}).
Equations \eqn{e:momentum} -- \eqn{e:Fz} describe the accretion shock mediated by radiation in the diffusion limit and provide the  structure of the zone where most of the accretion energy responsible for the formation of the emergent spectrum is released. The 'sinking zone' downstream the radiation shock, where the matter settles down subsonically and advects thermal energy towards the NS surface,
should be treated separately (see e.g. \cite{BaskoSunyaev76}). Different physical
effects can appear in this zone, e.g. 'photon bubble oscillations' discussed in \cite{1992ApJ...388..561A,1996ApJ...457L..85K}.

\subsubsection{Equations in dimensionless form}

The convenient  variables are dimensionless velocity of matter squared $Q=v^2/v_0^2$,  the dimensionless column radius $\tilde{r}={\varkappa_T S_0}r/{c}={\tau_T v}r/{c}$ and height $\tilde{z}={\varkappa_T S_0}z/{c}={\tau_T v}z/{c}$, where  $S_0=S(\dot M_{17}=1)=8.79\times 10^6~\mbox{\rm erg~s$^{-1}$~cm$^{-2}$}$ (here and below $\dot M_{17}=\dot M/(10^{17}\hbox{g\,s}^{-1})$ is dimensionless mass accretion rate onto one pole).
For the assumed value of $r_0(\dot M_{17}=1)$ the dimensionless factors almost exactly equal to $10^{-4}~\mbox{cm}^{-1}$.
For the scattering cross-sections we shall assume $\varkappa_\bot=\varkappa_T$ and $\varkappa_T/\varkappa_\|=10$.

With this notation and dimensionless variables, the system of equations (\ref{e:r-density}), (\ref{e:energy}), (\ref{e:Fr}), (\ref{e:Fz}) is equivalent to one
non-linear partial differential equation  (cf. \cite{1973NPhS..246....1D})
\beq{e:q}
\tilde{K}_\bot\left[\frac{\partial^2 Q}{\partial \tilde{r}^2}+\frac{1}{\tilde{r}}\frac{\partial Q}{\partial \tilde{r}}\right] + \tilde{K}_\|\left[\frac{\varkappa_T}{\varkappa_\|}\frac{\partial^2 Q}{\partial \tilde{z}^2}-8\frac{\partial}{\partial \tilde{z}}\left(\!\sqrt{Q}-Q\right)\right]-\frac{\partial Q}{\partial \tilde{z}}=0,~
\end{equation}
where the coefficients
$\tilde{K}_\bot=\left(1+\frac{v_0}{6c(1-\sqrt{Q})}\left|\frac{\partial Q}{\partial \tilde{r}}\right|\right)^{-1}$ and   $\tilde{K}_\|=\left(1+\frac{\varkappa_T}{\varkappa_\|}\frac{v_0}{6c(1-\sqrt{Q})}\left|\frac{\partial Q}{\partial \tilde{z}}\right|\right)^{-1}$
are calculated at each consecutive iteration using values of $Q$ obtained in the previous iteration.

Equation (\ref{e:q}) was solved numerically using the finite difference approximation method. A time-relaxation scheme was used. In this approach, the equation in the form $L[Q]=0$, where $L$ is the corresponding differential operator, has been replaced by a parabolic equation of the form $\frac{\partial Q}{\partial t}-L[Q]=0$. The steady-state solution of the last equation coincides with the solution of the original elliptic equation. An explicit finite-difference scheme was used to solve the parabolic equation.

\subsection{Results of numerical calculations}
\label{s:res}

Numerical simulations were carried out for accretion rates onto one pole in the range
$10^{17}-1.2\times10^{18}~\mbox{\rm g~s$^{-1}$}$
for the hollow cylinder geometry and the filled cylinder geometry. The column structure at different accretion rates is shown in \Fig{f:Q}. Note that
at a given mass accretion rates and the NS magnetic field, the height of the braking zone in the hollow cylinder case is smaller than that in the case of the filled cylinder, as expected from the dependence of the radiation diffusion time on the
wall thickness $\propto b$. Clearly, in very geometrically thin walls, $b/r_0\ll 1$,
the flow will be
optically thin as well (at least for the extraordinary mode with angle-independent
scattering cross-section in the strong magnetic field). This may suggest that
even if the flow was initially confined within a thin layer, near the NS surface
the huge energy release may change the character of the flow. This possibility is worth investigating further.

Guided by the velocity braking in a radiation-dominated shock, $v\approx1/7 v_0$,
we define the 'height' of the accretion mound $z_0(\dot{M})$ as the distance
at the centre of the structure where the gas flow velocity is reduced to one seventh of the initial value. The (dimensionless) height calculated for different accretion rates were fitted by a power law
\beq{}
\tilde{z}_0=\beta\dot{M}^\alpha_{17},
\end{equation}
where $\tilde{z}_0=\varkappa_T S_0 z_0/c$. We found that in both geometries
$\alpha\sim 1$ and $\beta>0$ ($\alpha\simeq 1.1$, $\beta\simeq 0.3$ for the case of hollow cylinder
and  $\alpha\simeq 0.9$, $\beta\simeq 13.5$ for the filled cylinder).
Therefore, the numerical solution behaves in agreement with the qualitative
physical considerations about the structure of optically thick accretion mounds described above.

\section{Change in the hardness ratio from accretion columns}
\label{s:spectrum}

\subsection{Saturated Compton spectrum of sidewall emission}

\begin{figure}
\includegraphics[width=0.48\textwidth]{Fr_rev.pdf}
\caption{
The radial energy flux $F_r(\tau=2/3,z)$ calculated along the height
of a filled cylinder column
at different mass accretion rates. Half of this flux (extraordinary photons
only) escapes
sidewall. The lines from bottom to up correspond to
$\dot M_{17}=2$, 3, 5, 8 and 12, respectively.
}
\label{f:F_r}
\end{figure}

\begin{figure*}
\includegraphics[height=0.34\textwidth]{Spectra_col.pdf}
\hfill
\includegraphics[height=0.34\textwidth]{HR_fil_col_rev.pdf}
\caption{
Left:
The spectrum of sidewall emission from optically thick filled cylinder accretion column
\eqn{e:IF}
for mass accretion rates $\dot M_{17}=2$, 3, 5, 8 and 12
(from bottom to up, respectively).
Right: The spectral hardness ratio $HR$
as a function of mass accretion rate.
}
\label{f:col_spec}
\end{figure*}

The LTE treatment of the spectrum of the sidewall emission from
accretion columns is clearly a strong oversimplification. To take into
account the scattering on electrons in the optically thin boundary of the column, we
can use the model calculations of the radiation transfer problem
in a semi-infinite plane-parallel atmosphere with strong magnetic field.
In this case the emerging
spectrum will be formed in the saturated Compton regime, with the mode 1 photons (extraordinary, i.e.
polarized perpendicular to the $\bm{k}-\bm{B}$-plane,
where $\bm{k}$ is the photon wavevector and $\bm{B}$ is the magnetic field vector)
predominantly escaping through sidewalls \citep{1986Ap.....25..577L}. The intensity
of mode 2 (ordinary, i.e. polarized in the $\bm{k}-\bm{B}$ plane) photons is comparable to
that of mode 1 photons only at large angles to the normal, $\mu'\sim 0$,
and thus insignificantly contribute to the total flux from the unit surface
area due to the
geometrical factor.

In this regime,
the specific intensity of extraordinary photons
at energies far below the cyclotron resonance can be written to an accuracy of
a few per cents as \citep{1986Ap.....25..577L}
\beq{e:I1}
I_\nu'=\frac{2\sqrt{3}}{5}(1+2\mu')\frac{h\nu \nu_g^2}{c^2 \tau_0}e^{-\frac{h\nu}{kT}}\,,
\end{equation}
where $\mu'=\cos\theta'$ is the angle between the normal to the atmosphere and
the escaping radiation direction in the plasma reference frame, $\tau_0$ is the characteristic optical depth of the problem, $\nu_g=\frac{eB}{2\piup m_ec}$ is the electron gyrofrequency in the magnetic field. By expressing the characteristic optical depth $\tau_0$ through
the emergent radiation flux $\Phi$ using Eqs. (34-37) from \cite{1986Ap.....25..577L},
we find
\beq{e:IF}
I_\nu'=\frac{3}{10\piup}\myfrac{h\nu}{kT}^2\frac{\Phi}{\nu}e^{-\frac{h\nu}{kT}}\,.
\end{equation}

Therefore, we are in the position to calculate the emerging spectrum from the column
in this approximation using the solutions for the column structure obtained above.
To do this, it is sufficient to substitute the total radial energy flux
at each height of the column $\Phi\to F_r(z)/2$, and temperature $T\to T(z)$ estimated
deep inside the column (at the optical depth $\sim 1$),
so that $T(z)=(U(z)/a_r)^{1/4}$). Note here that at large optical depth
the number density of ordinary and extraordinary photons are equal, with the
extraordinary photons becoming overwhelmingly dominant in the optically thin outer
layers. Therefore, only half of the radial energy flux, $F_r(z)/2$, should
be taken into account in the spectral calculations. The second half of
the radial flux (in ordinary photons) is admixed to the vertical energy flux
component, $F_z$. Some fraction of this energy flux can propagate (mostly
as ordinary photons) along the magnetic field into the optically thin upper
part of the column;  we do not calculate their fate in this paper and
restrict ourselves by this quantitative note.
The radial energy flux $F_r(z)$ from
the filled column is shown in Fig. \ref{f:F_r} for different mass accretion
rates.

The resulting
spectra of the sidewall emission from
the optically thick accretion column integrated over the column height $z$
is shown in Fig. \ref{f:col_spec} (left panel) for the case of the filled column and different
$\dot M$. The spectral hardness ratio
\beq{}
HR=\frac{\int\limits_{5~\mathrm{keV}}^{12~\mathrm{keV}}F_\nu d\nu}
{\int\limits_{1.3~\mathrm{keV}}^{3~\mathrm{keV}}F_\nu d\nu},
\end{equation}
is shown in the right panel of this figure as a function of $\dot M$. It is
seen that the hardness ratio of the spectrum of the column monotonically
increases with mass accretion rate.

\subsection{Account for the reflected component}

We have seen that the saturated-Comptonized spectrum of sidewall
emission from optically thick accretion column gets harder with increasing $\dot M$,
contrary to what is observed and discussed above. However, an important feature of
accretion in X-ray pulsars should be added at this point.
Namely, we should take into account the fact that the electrons in the optically thin part of the column are moving
with high velocity $v_0\sim 1/3 c$,
and thus the emission beam of the column
\eqn{e:I1} should be Doppler-boosted towards the neutron star surface and reflected from the neutron star atmosphere, as discussed
in \cite{1988SvAL...14..390L} and \cite{2013ApJ...777..115P}. The reflection coefficient in the case of single Compton electron scattering
in strong magnetic field is determined by the ratio $\lambda(\nu)=\kappa_{sc}/(\kappa_{sc}+\kappa_{abs})$, where $\kappa_{sc}$ and $\kappa_{abs}$
is the scattering and absorption coefficients for photons in the strong magnetic field, respectively.
The reflection coefficient (X-ray albedo) is calculated in the Appendix
\ref{s:appendix} and is presented in Fig.
\ref{f:albedo}. Note that the calculated X-ray albedo turns out to be very similar for
both extraordinary and ordinary photons and is virtually insensitive to
the photon incident angle to the magnetic field.
Everywhere below we shall use X-ray albedo for extraordinary photons only.
It is seen that soft photons are mostly
absorbed, while hard photons are reflected by the neutron star atmosphere.
Therefore,  the reflected spectrum  is harder than the incident one.

\begin{figure}
\includegraphics[width=0.48\textwidth]{Albedo.pdf}
\caption{
The single-scattering Compton X-ray albedo from a plane-parallel
neutron star atmosphere with strong magnetic field. The electron number
density is $n_e=5\times 10^{25}$~cm$^{-3}$, electron temperature $T=3$~keV,
magnetic field $B=3\times 10^{12}$~G,
photon incident angle to the magnetic field $\piup/4$.
Extraordinary and ordinary
photon spectra are shown by the solid and dashed lines, respectively.
The cyclotron line is ignored.
}
\label{f:albedo}
\end{figure}

Let $\alpha$ be the angle between the photon wavevector and
the plasma bulk velocity vector.
Due to the boosting, part of radiation from the column
will be intercepted by the neutron star surface and reflected.
The critical angle $\alpha^*$ within which the radiation from the
height $z$ above the surface will be intercepted
by the neutron star (in the Schwarzschild metric) is \citep{2013ApJ...777..115P}
\beq{}
\sin \alpha^*=\frac{R_{NS}}{R_{NS}+z}\sqrt{\frac{1-r_S/(R_{NS}+z)}{1-r_S/R_{NS}}},
\end{equation}
where $r_S=2GM/c^2$ is the Schwarzschild radius. The difference between the polar axis and the column cylinder side can be neglected for $r_0\ll R_{NS}$.

Let $\Sigma$ be the surface of the column, $\Sigma'(\varphi, z)$ be a point on the surface and
$d\Sigma=r_0 d\varphi dz$ be the elementary area.
The flux from the surface element at frequency $\nu$ (in conventional notations) reads
\beq{ell}
f_\nu(\Sigma')=\frac{dE(\Sigma')}{dtd\nu r_0d\varphi dz}
\end{equation}
and can be separated into three parts in accordance to the angle relative to the observer.
Photons escaping with angles $\alpha>\alpha^*$ to the column are directly seen
as the proper column radiation $f_\nu^{col}$.
The second part includes the radiation $f_\nu^{ref}$ intercepted by the
neutron star and reflected
from the neutron star surface with X-ray albedo $\lambda (\nu)$.
The third part $f_\nu^{abs}$ is the radiation absorbed and re-radiated
by the neutron star atmosphere. Then we can write:
\begin{eqnarray}
\label{dL}
&f_\nu(\Sigma')= \int\limits_{-1}^1\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha \nonumber\\
&=\int\limits_{-1}^{\cos\alpha^*}\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha + \int\limits_{\cos\alpha^*}^1\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha \nonumber\\
&=\int\limits_{-1}^{\cos\alpha^*}\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha\nonumber\\
&+\lambda(\nu)\int\limits_{\cos\alpha^*}^1\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha +
(1-\lambda(\nu))\int\limits_{\cos\alpha^*}^1\frac{d f_\nu(\Sigma')}{d \cos \alpha} d\cos\alpha\nonumber\\
&=f_\nu^{col}(\Sigma')+f_\nu^{ref}(\Sigma')+f_\nu^{abs}(\Sigma').
\end{eqnarray}
The integrands \citep{2013ApJ...777..115P} in the cylindrical coordinates
with account for the axial symmetry ($I_\nu(\Sigma')=I_\nu(z)$, giving by (\ref{e:I1}))
have the form:
\beq{dLdcos1}
\frac{df_\nu(\Sigma')}{d\cos\alpha}
=I_\nu(z)\frac{2D^3}{\gamma}\sin\alpha\left(1+\frac{\piup D}{2}\sin\alpha\right),
\end{equation}
where the Doppler factor is $D=1/(\gamma(1-\beta\cos\alpha))$,
$\gamma=1/\sqrt{1-\beta^2}$ is the plasma Lorentz factor and $\beta=v/c$.
Here we have taken into account that the specific flux (per unit frequency interval) is $D$ times as small as the integral flux.
Then for the total radiation from the column at frequency $\nu$ we obtain:
\begin{eqnarray}\label{L}
&L_\nu = \iint\limits_\Sigma f_\nu(\Sigma')d\Sigma
=2\piup r_0\int\limits_0^{z_{max}}f_\nu(z)dz\nonumber\\
&=2\piup r_0\int\limits_0^{z_{max}}(f_\nu^{col}(z)+f_\nu^{ref}(z)+f_\nu^{abs}(z))dz\nonumber
\\
&=L_\nu^{col}+L_\nu^{ref}+L_\nu^{abs},
\end{eqnarray}
where $z_{max}$ is the upper limit of the computational area.
The observed X-ray flux from one column is
$F_\nu=(L_\nu^{col}+L_\nu^{ref})/(4\piup d^2)$, where $d$ is
the distance to the source. For the illustrative purposes, we assume
$d=5$~kpc.
Taking into account of the radiation absorbed by the neutron star
atmosphere $L_\nu^{abs}$ will add more soft photons to the total spectrum.

Since we are observing both the direct and reflected radiation from the column,
the total change in the hardness of the spectrum will depend on the fraction of the
reflected radiation in the total flux. This, in turn, depends on the
height of the column. We have calculated the total flux as the sum of the direct and reflected component as a function of $\dot M$ with taking into account the
photon ray propagation in the Schwarzschild metric of the neutron star
with a fiducial mass $M=1.5 M_\odot$ and radius $R=10$ and 13~km.
The magnetic field of the neutron star is set to $3\times 10^{12}$~G, so that the
CRSF energy is about 35 keV.
The result is presented in Fig. \ref{f:total}. It is seen that the hardness ratio
$HR$ first increases with the mass accretion rate (X-ray luminosity), but starting
from $\dot M_{cr}\sim (6-8)\times 10^{17}$~g~s$^{-1}$ it gets saturated and even decreases.
This is in agreement with observations shown in Fig. \ref{f:hardness}.

For the hollow cylinder accretion columns which have smaller height
(see Fig. \ref{f:Q}), the fraction of the reflected component
in the total emission does not virtually change with mass accretion rate within the calculated range, therefore the hardness ratio of the total spectrum monotonically
increases with $\dot M$ in this range (see Fig. \ref{f:hr_hol}). Note also
that in this case the spectrum is harder than in the case of the filled column because
the reflected (harder) emission dominates in the total spectrum.

\begin{figure*}
\includegraphics[height=0.34\textwidth]{Spectra_ref_rev4.pdf}
\hfill
\includegraphics[height=0.34\textwidth]{HR_fil_rev4.pdf}
\caption{
Left: the total spectrum of direct sidewall and reflected
from the neutron star atmosphere from the optically thick filled
accretion column for mass accretion rates $\dot M_{17}=2$, 3, 5, 8 and 12
(from bottom to up, respectively).
Right: the hardness ratio $HR$ of the total spectrum.
Shown are calculations for the neutron star radius $R_{NS}=10$~km (squares) and $R_{NS}=13$~km
(circles).
}
\label{f:total}
\end{figure*}

\section{Summary and conclusions}

In this paper, using RXTE/ASM archival data we studied the
behaviour of the spectral hardness ratio as a function of X-ray luminosity at different accretion
rates in a sample of six transient X-ray
pulsars (EXO 2030+375, GX 304-1, 4U 0115+63, V 0332+63, A 0535+26 and
MXB 0656-072). In all cases, the hardness ratio
is found to increase with X-ray flux at low luminosities and then to
saturate or even slightly to decrease above some critical
luminosity of a few times $10^{37}$~erg~s$^{-1}$
This behaviour confirms earlier findings by
\citet{Reig:Nespoli:13}, and \citet{Klochkov:etal:11}
and correlates with the behaviour of the CRSF energy with flux
in the CRSF sources.

At low mass accretion rates and low X-ray luminosities,
the braking of infalling matter is expected to be mediated by Coulomb interactions
\citep{1969SvA....13..175Z, 1993ApJ...418..874N, Becker_ea12} and occurs close to the neutron star surface,
essentially at a height of the homogeneous atmosphere above the neutron star surface,
without the formation of an accretion column. When the X-ray luminosity increases above some
critical value $\sim 10^{37}$~erg s$^{-1}$
\citep{1973NPhS..246....1D, BaskoSunyaev76, 1981A&A....93..255W, 2015MNRAS.447.1847M},
the radiation pressure of generated photons decelerates the infalling matter.
An optically thick accretion column arises with the height increasing almost linearly with accretion rate.

\begin{figure}
\includegraphics[width=0.48\textwidth]{HR_hol_rev4.pdf}
\caption{
Hardness ratio of the total emission (direct plus reflected from the
neutron star atmosphere) from a hollow cylinder accretion column
with $b=0.1r_0$ as a function of mass accretion rate $\dot M$.
}
\label{f:hr_hol}
\end{figure}
Therefore, at low luminosities $< L^*\sim 10^{37}$~erg s$^{-1}$
the emerging X-ray spectrum is essentially
formed by ordinary photons in a magnetized optically thin atmosphere. The hardness of the spectrum
is determined by the Comptonization $y$-parameter, $y=(kT/m_ec^2)\tau$,
which increases with accretion rate. This implies that in this case the hardness of the emerging radiation will increase with luminosity.

At higher luminosities an optically thick accretion column above the
magnetic pole arises, and thermal radiation generated deep inside
the column escapes sidewall predominantly as extraordinary
photons. Since at energies far less than the CRSF energy
the electron scattering cross-section strongly decreases with
frequency, the spectrum of the emergent continuum radiation will be
softer than the diluted Wien spectrum expected
to be formed in the saturated Compton
regime, $\sim \nu e^{-h\nu/kT}$ \cite{1986Ap.....25..577L}.

We have calculated the structure of axially symmetric optically thick accretion columns in the diffusion approximation for radiation transfer
for different mass accretion rates. Two accretion column geometries, filled cylinder and hollow cylinder, were considered.
In both cases we have found the expected almost linear growth of the column height with mass accretion rate.
The continuum X-ray spectrum of the sidewall emission in both geometries gets
harder with increasing mass accretion rate. Taking into account of
the radiation reflected from the neutron star atmosphere allowed us to
reproduce the observed saturation of the continuum hardness. This is purely
geometrical effect: with increasing mass accretion rate the height of the
column increases, so does the fraction of the reflected radiation. However,
starting from some height, the fraction of the reflected radiation in the
total flux stops
increasing and starts decreasing. Since the hardness of the reflected
radiation is higher than that of the incident emission  (because of the
strong energy dependence of the scattering and absorption coefficients in
the strong magnetic fields), the hardness of the total spectrum (direct
sidewall emission from the accretion column plus reflected radiation from
the neutron star atmosphere) saturates (and even can slightly decrease) beyond
some characteristic mass accretion rate $\sim (6-8)\times 10^{17}$~erg s$^{-1}$ for the
typical
neutron star parameters: $M_{NS}=1.5 M_\odot$, $R_{NS}=10$~km and 13~km, $B=3\times
10^{12}$~G.

In the case of the hollow cylinder accretion column geometry with a fiducial
wall thickness of $0.1$ the outer column radius $r_0$,
we have not found the spectral hardness ratio saturation with increasing
mass accretion rate up to the maximum value of our calculations
$1.2\times 10^{18}$~g s$^{-1}$. Apparently, the height of the column in this case is
too low, the hard reflected component dominates at all mass accretion rates,
and the (softer) direct sidewall emission remains subdominant in the total
spectrum.

Therefore, our model calculations lead to the following conclusions.

1. The spectral hardening in X-ray pulsars with positive CRSF energy
dependence on X-ray flux can be explained by increasing of the
Comptonization parameter $y$ in the slab atmosphere of the accretion mound.
It is in this regime that
positive correlation of the cyclotron line is observed, for example,
in Her X-1 \citep{2007A&A...465L..25S}.

2. At high accretion rates, the radiation-supported optically thick
accretion column grows above the polar cap,
the sidewall emission from the column is formed by extraordinary photons
in the saturated Compton  regime. The spectrum of this emission gets
harder with increasing mass accretion rate.

3. With further increasing mass accretion rate the height of the column
increases, such that the fraction of radiation reflected from the neutron
star atmosphere starts decreasing. As the
reflected radiation is harder than the incident one, the
spectrum of the total emission
(direct plus reflected) stops hardening (and even becomes slightly softer).
This happens at the mass accretion rate onto one pole $\dot M_{cr}\sim (6-8)\times 10^{17}$~g s$^{-1}$, in qualitative agreement with observations (see Fig. \ref{f:hardness}).

4. In the frame of this model, the saturation of
the spectral hardness in the case of a hollow cylinder geometry of the
accretion column can be achieved at much higher accretion rates (roughly,
scaled with the relative thickness of the column wall, $r_0/b$),
 because the characteristic height of the column in this
case is correspondingly smaller than that of the filled column.

5. Variations in the pulse profile form and polarization
properties during the transition from the Coulomb-braking low-luminosity
regime to the radiation-braking high-luminosity state should occur
with changing mass accretion rate (X-ray luminosity) in accreting X-ray pulsars.
The profile change has already been reported during the low-states in Vela X-1
\citep{2011A&A...529A..52D}.

We conclude that X-ray continuum observations in transient X-ray pulsars
can be used as additional diagnostic of different accretion regimes
and column geometry near the surface of highly magnetized neutron stars.

\section{Acknowledgements}

MG, NSh, VL and acknowledge the Russian Science Foundation grant 14-12-00146. The work of KP and DK is supported by RFBR/DFG grant KL 2734/2-1 (RFBR-NNIO 14-02-91345).

\bibliographystyle{mn2e}

redpajama_set_name: RedPajamaArXiv


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Q: Is there a favorite room you have designed or project you have completed?
SB: I am always up for a challenge and love it when clients bring me unusual requests; whether it's designing a display room for a special mineral collection or crafting a custom kitchen into the perfect functional space. I also love designing for children and pets!
A passion of mine is designing both historic properties and modern architectural spaces. I always strive to bring harmony, balance and a connection to nature to the space.
Q: What design trends are you most excited about in 2017?
SB: There are three major themes and trends that I am excited about: Handmade furnishing items from natural materials, made by artists, not factories. Collecting! There has never been a better time to support the arts and start or expand a collection of paintings, sculptures and/or pottery. Customizable textiles printed by local artisans - personalization has never been easier!
Q: What do you recommend as first steps to those who may be unfamiliar with smart design and sustainable choices?
SB: Start small. Sometimes just a few simple changes can have an enormous impact on the health of your home or work environment. If you aren't ready to redesign your entire home, I often recommend starting with the master bedroom since this is where we spend a good portion of our time. This room above all others needs to feel restorative and calming.


text:
Ultimate Software Acquired for $11B. What Does It All Mean?
The Top-line Context
The hits keep on coming. Ultimate Software, a leading HCM cloud provider, got acquired for an approximate aggregate value of $11 billion, meaning shareholders received about $331.50 per share in cash.
The investor group was led by private equity firm Hellman & Friedman, and also included Blackstone Group LP, GIC Private Limited, Canada Pension Plan Investment Board (CPPIB), and JMI Equity. The price represents a 32 percent premium over Ultimate's volume-weighted average price in the 30 days ending on Feb. 1. Ultimate, which had won Fortune's Best Technology Workplace for four straight years, will probably get a fifth straight title, because the deal makes a few handfuls of employees into millionaires.
So What Does the Ultimate Software Acquisition Mean?
HCM is still a white-hot investment market in 2019. Average companies can do well. Great companies are going to see amazing returns. It's a strong vote of confidence in the space for the foreseeable future. As Reuters noted in its coverage of the acquisition, cloud HCM is expected to touch $22.17 billion in 2023, up from $13 billion in 2016. That's some cheddar.
2018 was private equity's biggest year since the 2008 recession, and the Ultimate deal is roughly 2.5 times bigger than Marketo being sold off to Adobe in 2018 by Vista Equity Partners. That deal was notable at the time for (a) sheer size and (b) speed of turnaround, since the business was initially taken private in 2016 for $1.8 billion. Usually the turnaround on private equity deals is closer to five years. Ultimate's acquisition will likely get less media attention, but might ultimately (ha! Get it?) mean more to the marketplace.
Who Could Ultimate Eventually Be Sold To?
This is an interesting question. Typically, if private equity partners buy a company, they think it's either undervalued or could gain significant value in the next five years for a sell-off. But who could Ultimate's next buyer be?
If you look at basic cash on hand, there are two logical options: Alphabet Inc. (i.e., Google) or Microsoft. Apple, Facebook, and Amazon would be longshots with the cash potential. The final interesting possibility here is Salesforce, which contributed heavily to a recent $20 million round of funding, designed to fuel the growth and international expansion of their platinum partner, Simplus. While CNBC and others have recommended Apple buy Salesforce in the past, Salesforce acquiring Ultimate to combine traditional HCM and traditional CRM might actually make Salesforce itself a more attractive acquisition for someone looking to topple the Microsoft-LinkedIn partnership.
Though that partnership hasn't fully fleshed itself out, let's remember that $26 billion is significantly more than $11 billion. So for all the hot takes on Ultimate — and they deserve to be stated — it's still less than half of LinkedIn's perceived value a few years ago. Does that discussion factor into what happens with Ultimate next?
You think we read this ball wrong off the bat? Let us know your takes on it. Specifically: Do you think this extends the HCM runway into the mid-2020s? How might Ultimate's core offerings improve? We'd love to hear your thoughts.
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Randy Wants For You To See This.
Tomorrow sees the release of the relaunch of Adventure Comics. For decades, Adventure Comics was up there with Action, Superman, Detective and other National/ DC Comics. It carried a lot of stories, but became well known for the Super-Family and Legion stories. Somewhere along the line they ended Adventure Comics, and added the Super Family title and gave Legion its own title.
After several Legion relaunches in the past few years, I am hoping this stabilizes the futuristic "Legion of Super-Heroes", which is contained as a back-up feature.
The main feature will contain stories of the modern Superboy, Conner Kent. And Krypto, the Superdog. And for that, I am very glad.
Add to it, the writing of Geoff Johns and art of Francis Manapul, and this series has as much potential as any new series from DC in years.
Just, you know, with two dogs.
Here's some more Superman stuff, too.
We adore Lucy. She is a sweet and loving dog, and she tries very hard, but we've always known that maybe she wasn't going to be getting into dog-Harvard.
But Scout just decided this evening to know how to fetch. Just sort of watched Lucy and decided "well, I can do that". She is learning her name. She knows where we're trying to guide her. She's cluing into the hints of dwelling with the family.
And, knock on wood, she really seems potty-trained. She just stood at the door and waited for me a few minutes ago after sniffling at my hand for attention.
I know that in a week or two, she and Lucy will not be growling at each other. And we'll be able to introduce her to Cassidy soon enough (I need to do some reading on best practices there).
It might be a bit bumpy at first, but in the end it will be good to have Scout socialized so that she can tolerate being around other dogs, and having Lucy around will be a good part of that process.
Here's an observation from this morning. I left the two of them alone while showered, etc... and they're fine. I sort of think Scout is just not sure how to share us anymore than she knows how to share Mr. Bun.
Last night was actually better than Monday night. Its a process.
It's weird seeing Mon El in present day instead of in the future. Mon El should be with the Legion. Seeing as I don't even read Superman titles, is Mon El still even a Daxamite?
Also, DC just needs to give the Legion title back to Keith Giffen.
Yup, Mon-El is a Daxamite in current continuity. My guess is that they're using this storyline to establish why he becomes a Legionnaire by choice rather than default.
There's another Daxamite in the GL Books right now (Sodam Yat), and he was just asked not to come to Earth to meet Mon-El by a time-lost Legionnaire I'd seen a few times before, but whose name always escapes me.
I saw Green Lantern - First Flight today and called it good. I thought Jordan's voice acting was a bit wooden, but it just may be they didn't give him much of a character arc. Sinestro? Spot on.


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