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By Avlin on
Are you looking into a career in nursing? Qualifying as a Certified Registered Nurse Anesthetist (CRNA) is one of the most profitable and interesting nursing careers in healthcare. CRNAs have the task of administering anesthesia and pain-relief medication to patients during medical procedures.
What Is The Average For An Anesthetist Nurse Salary?
What Is An Anesthetic Nurse?
What Are The Steps To Becoming An Anesthetic Nurse?
Step 1 – Earn Your BSN Degree
Step 2 – Pass Your NCLEX Exams and Receive RN Licensing
Step 3 – Gain Experience Nursing in Critical Care Units
Step 4 – Enroll In a Nurse Anesthesia Course
Step 5 – Graduate With a DNP or DNAP And Pass Your National Certification Exam (NCE)
Step 6 – Start Your Career as a CRNA.
Anesthetic Nurse Education Requirements
Earning Your BSN Degree
Requirements For Admission
Time to Completion
Skills Acquired
Doctor of Nursing Practice (DNP)
Doctor Of Nursing Practice or Doctor of Nurse Anesthesia Practice?
Doctor Of Nurse Anesthesia Practice
Nurse Anesthetist Credentials
CRNA Certification
CRNA Licensure
FAQs On Becoming an Anesthetist Nurse
Q: How Long Will It Take for Me to Qualify as a CRNA?
Q: Is It Challenging to Become a Nurse Anesthetist?
Q: Do Nurse Anesthetists Receive a Good Salary?
These Advanced Practice Registered Nurses (APRNs) are some of the highest-earning professionals in nursing and benefit from considerable autonomy in their practice. The demand for qualified CRNAs is higher than ever, and the US Bureau of Labor Statistics (BLS) projects these jobs to grow by up to 12% between 2021 and 2031, that's 6% higher than other RN specialties.
So, what can you expect to earn for an anesthetic nurse's salary? Is it worth pursuing this specialty as a career? Let's unpack everything you need to know about the remuneration for a CRNA.
According to the Bureau of Labor Statistics, the average anesthetic nurse salary in 2022 in the US is $195,610 USD per year. This equates to $16,300 per month, and $4,075 per week.
ZipRecruiter states the average anesthetic nurse salary in 2022 in Canada is CAD$169,308 per year. That equates to an hourly wage of around CAD$81.40, CAD$3,255 per week, or CAD$14,109 per month. However, there are instances of CRNAs earning salaries ranging from a high of CAD$323,000 per annum to a low of CAD$97,500.
Most Nurse Anesthetist's salaries range between CAD$166,500 in the 25th percentile to CAD$197,500 in the 75th percentile. The top earning bracket sees these professionals walk away with salaries of CAD$225,000 in the 90th percentile.
Average pay ranges depend mostly on the practitioner's location and experience. Based on the quantity of new job listing activity on ZipRecruiter, Nurse Anesthetists may find it challenging to secure a job in the Canadian market due to few positions being offered.
A CRNA or APRN has specialized training in pain relief and anesthesia. APRNs determine patients' anesthesia and pain relief requirements during surgery and other medical procedures. They're responsible for administering anesthesia and prescribing scheduled pain medication.
Nurse anesthetists work in several medical environments, including surgical centers, hospitals, private practices, and clinics. In rural healthcare facilities and clinics, CRNAs and APRNs may only act as anesthesia specialists, while they typically work with anesthesiologists in hospital settings.
Typically, it takes around seven to ten years of specialized training and education to qualify as a nurse anesthetist. The duration to receive a full qualification, certification, and licensing depends on where you intend to practice.
You'll need to earn your four-year Bachelor of Science degree in nursing (BSN). After that, you must pass the National Council Licensure Examination for Registered Nurses (NCLEX-RN). You'll follow up by completing a Doctor of Nursing Practice (DNP) or Doctor of Nursing Anesthesia Practice (DNAP) degree, which occupies you for a further three years.
After completing your doctorate, you'll have to pass the National Certification Exam (NCE) set by the National Board of Certification and Recertification for Nurse Anesthetists (NBCRNA). Let's unpack the education process in detail.
It takes candidates up to four years to earn their Bachelor of Science in Nursing degree (BSN). Some anesthetist nurses start their careers by earning their Associate Degree in Nursing (ADN). This qualification is more demanding than a BSN, taking two years to complete. However, the AND is seen as a lower-level certification.
Many educational institutions offer RN-to-BSN courses, with some offering a Master of Science in Nursing (MSN) program, including a bridging option for students with an ADN qualification.
Students with BScs in non-nursing fields may enroll in accelerated BSN programs, earning their BSN in two to three years, depending on the credits they transfer from their previous qualification.
All students studying for their RN qualification must undertake and pass the National Council Licensure Examination for RNs (NCLEX-RN). This exam is computer adaptive and takes approximately six hours to complete.
The test covers nursing practices, conditions and treatments, healthcare systems, teamwork, and patient communication. RNs must also pass a state-issued background check before receiving a qualification in the field.
All CRNA and APRN programs require the candidate to complete between one to three years of critical care experience in surgeries, intensive care units (ICUs), or emergency and trauma centers.
This training in critical care teaches the RN to deliver medical interventions to patients with critical injuries or illnesses. These scenarios will include life-threatening situations for the patient, teaching the student how to cope with the stress and pressure of these situations.
In 2022, the minimum educational requirement for aspiring CRNAs and APRNs is a Doctor of Nurse Anesthesia Practice (DNAP) or Doctor of Nursing Practice (DNP) instead of an MSN. Students may select their specialty during their DNP program, whereas the DNAP curriculum is already specialized.
Most CRNA graduate programs require the applicant to have a minimum 3.0GPA, with some educational institutions requiring a minimum 3.5 GPA to enroll at the school. Applicants must also submit an essay motivating why they should be selected to attend the school.
Success with your NCE determines a candidate's competency for working at an entry-level practice. These candidates must hold a DNAP or DNP degree and an RN license. The NBCRNA charges approximately $995 to take the exam, with the cost increasing to $1,045 as of January 2023.
This computer-adaptive test lasts three hours, consisting of between 100 to 170 questions covering basic science topics like instrumentation, equipment, and medical technology. It also covers principles of anesthesia for surgical procedures and special requirements.
In most states, a CRNA must have an APRN license. Each state licensing board determines the scope of practice for CRNAs and the level of supervision required.
The final step in the process is to take a position at a surgical center or hospital. The aspiring APRN will work alongside a surgeon, anesthesiologist, and the anesthesia team. Individuals may also work in military bases, medical offices, and clinics where they lead the anesthesia team.
In these environments with limited resources, such as rural clinics, the APRN may act solo as the primary anesthesia professional on site. CRNAs may have an independent practice and work solo, depending on the state.
So, what are the primary educational requirements for earning your qualifications as a CRNA or APRN? Let's unpack them in detail.
The two-year ADN degree is the minimum qualification required for your RN license. Most nursing programs at the graduate level prefer the candidate to have a BSN degree. Some programs have a bridge component allowing ADNs to complete a program, giving them the equivalent certification of a BSN degree.
Most CRNA and APRN programs require the candidate to have a 3.0 GPA or higher, with 3.5 being the preferred score for elite medical training institutions. The candidate must successfully complete prerequisites in science, math, biology, and chemistry.
The BSN program typically includes courses on physiology and anatomy, statistics, effective nursing practice, community health, and medical ethics.
Most candidates take four years to earn their BSN degree after leaving high school. Candidates with an ADN or bachelor's degree in other fields of healthcare and science may transfer their credits to fast-track their progress through the BSN program.
The BSN program prepares the candidate for administering medications and physical examinations. Applicants must also learn the specifics of monitoring patients and understand and work in healthcare settings as part of a team.
The aspiring CRNA pursues a DNP degree through a nursing school accredited by the American Nurses Credentialing Center (ANCC). Alternatively, they earn a DNAP certification through the Nurse Anesthetists Council of Accreditation (NACA).
CRNAs must also take time to specialize in fields like adult cardiac anesthesiology, chronic pain management, and pediatric anesthesiology.
Most DNAP/DNP education programs require the candidate to have a minimum 3.0 GPA, with 3.5 GPAs being preferable. Given the competitive nature of the industry, a 3.5 GPA is becoming the more common standard for acceptance.
They must also secure an unrestricted RN license and have one to three years of experience working in critical care environments, with professional references.
The DNAP and DNP curriculum includes courses in pharmacology, epidemiology, risk management, safety, and advanced evidence-based medical practices. Candidates must also undergo training in healthcare legality and organizational leadership with clinical residencies.
Those candidates with an MSN will finish their DNP qualification in approximately one to two years, with a BSN student finishing in three to four years.
The aspiring nurse anesthetist candidate must learn to apply this research to a new practice, employ the latest technology, utilize sound judgment in clinical settings, and topics related to administering and planning anesthesia and pain relief.
There are several educational options to assist CRNAs in satisfying the doctoral-level degree requirements. The DNAP and DNP are options.
The highest degree in nursing practice. This qualification is essential for teaching in university positions.
The DNP is only available through medical nursing schools.
The American Association of Colleges of Nursing (AACN) defines the DNP curriculum and course standards.
It's more common for candidates to undergo certification with the DNP program than the DNAP.
The DNP doctoral degree focuses on practice over research.
A DNAP degree is available from universities and nursing schools.
The Council on Accreditation of Nurse Anesthesia (CANA) approves all DNAP programs.
The DNAP is a practice-focused doctoral degree requiring nurse anesthesia practice and management/administration.
All nurse anesthetists must have certification and licensing to practice anesthesia. The state is responsible for administering and regulating licensure, and the NBCRNA manages all credentials of nurse anesthetists.
The NBCRNA exam tests the candidate's knowledge of anesthesia practices for use in the field. DNP and MSN students will undertake specialized nursing anesthesia courses; these DNAP programs have a specific design around these specialties.
Those candidates seeking an NBCRNA certification to qualify as a CRNA must pass their National Certification Exam. They must then earn a degree from accredited CRNA programs, hold an unencumbered RN license, and provide a sworn statement. The statement asserts the candidate doesn't have any condition that might limit their ability to administer anesthesia.
The CRNA licensing requirements differ between states. However, every state requires the candidate to undergo CRNA certification. Nurse anesthetists apply with the local state board of nursing for licensing.
Some states may require candidates to complete additional applications for physician supervision forms or prescriptive authorities. CRNAs must secure education credits to maintain their licensure in their state.
A: Earning your qualification as a CRNA requires around seven to ten years of intensive study in a university and specialized medical schools. You'll also need to undertake several years of critical care experience as a Registered Nurse working in theaters, emergency rooms, and other critical care facilities.
As of 2022, candidates looking to qualify as CRNAs can plan on spending two to three years completing a DNP or DNAP degree after securing their BSN qualification and RN license.
A: Yes. Studying to become a nurse anesthetist is highly demanding on your time. Most graduate-level programs require the candidate to have a minimum 3.0 GPA, with most preferring a 3.5 GPA for admission into DNAP and DNP programs.
The candidate will have to undergo intensive study in the fields of anatomy and physiology, pharmacology, and nursing practices. Some programs may only admit 10% of applicants, and others may only accept 20%.
A: Yes. As a nurse anesthetist, you can expect to walk into a job earning close to six figures, depending on your location and final qualifications. The lowest average salary for a CRNA is CAD$97,500, while the top 90th percentile of earners takes home approximately CAD$225,000 per annum.


text:
Tom Shippey's most recent book is Laughing Shall I Die: Lives and Deaths of the Great Vikings.
King shall hold kingdom
Æthelred the Unready
I lerne song
Medieval schooling
Keep your eye on the tide, Jock
What did he think he was?
Ælfred the Great
Troll-Descended Bruisers
'Njal's Saga'
The Most Learned Man in Europe
Anglo-Saxon Libraries
Tom Shippey
Helen Cooper
Chaucer's Language
Farmer Eliot
Marginalia in Renaissance England
Shakespeare's Bad Daughters
History, Cultural history, 500-1399, 500-999, 800-899, Europe, Western Europe, UK, England, Literature and literary criticism
Not so much 'Unready', more 'No-Idea'
The Anglo-Saxon Chronicle edited and translated by M.J. Swanton
Dent, 364 pp, £20.00, June 1996, ISBN 0 460 87737 2
In some respects The Anglo-Saxon Chronicle is a classic Post-Modern text. For one thing, it does not exist. It is a 'construct' of much later historians, obsessed with the discovery/invention/creation of a 'national Chronicle' as opposed to 'merely local annals', to quote the most influential of them, Charles Plummer, whose 1899 edition of The Anglo-Saxon Chronicle has still, significantly or ominously, not been replaced. Since the Chronicle is a Post-Modern work, even this brief account contains slurrings or inaccuracies, but one could press on by saying that even if it didn't exist before, it certainly does now. No modern historical work on the period is without its long index entry on Anglo-Saxon Chronicle, while the libraries of the world contain scores, if not thousands of books with that title on their spines, the product of equally large numbers of scholars. So of course 'The Anglo-Saxon Chronicle' exists. You could argue that it is a product of later English scholars rather than of Anglo-Saxons, but you could not deny that Anglo-Saxons wrote it, or them, or at least the words out of which it has been made. So, to put it Post-Modernly, what is this Anglo-Saxon Chronicle, and what do we mean by 'wrote'? How is the complexity which underlies the familiar three-word title to be presented in a manner true enough to be useful and simple enough to follow?
The last problem has not yet been solved and may with present technology still be insoluble. Seven complete manuscripts of what we call The Anglo-Saxon Chronicle currently exist, along with a fragmentary eighth, but none, at least of the five major manuscripts, constitutes any more of a unity than the Chronicle itself. Take the 'E' manuscript, the 'Peterborough Chronicle'. We know the manuscript we have was copied in Peterborough in the year 1121, as it is written out in the same handwriting up to that date. Since it is known that Peterborough Abbey suffered a disastrous fire in 1116, it is usually thought that the copy we have was written to replace a manuscript destroyed in the blaze. However, the 12th-century monk copying away in his scriptorium no doubt saw the fire as a (perhaps literally) heaven-sent opportunity to get the 12th-century Peterborough version of events accepted as part of an authentic-looking seventh-century text. His version of the Chronicle, and his alone, contains a long account of the foundation of the abbey by King Wulfhere in 656, with a firm statement by the King to the effect that within the boundaries given 'nan man ne haue pær nan ofsting buton seo abbot ond se muneces' ('nobody shall have any authority there except the abbot and the monks'), that 'pær ne be numen of na geld na gaule buton to pa munecan ane' ('neither tax nor rent shall be taken from it except for the monks alone'), and that it should be regarded on a par with Rome as a place of pilgrimage. There is no doubt that this is 12th, not seventh-century work: apart from the obvious self-interest, no real Anglo-Saxon would have put a masculine singular definite article in front of a plural noun ('se muneces'), nor produced the strange conflation of singular and plural, nominative/accusative and dative, seen in 'to pa munecan ane'. Those words were written at a time when the Old English inflectional system was breaking up, or had broken up, though the copyist made no effort to modernise the archaic forms of his original.
If the date of original composition could so easily be erased every time a manuscript was copied, are any annal numbers or any palaeographical indications in any of the manuscripts trustworthy? The general view, and the very foundation of the 'national Chronicle', is that the concept of The Anglo-Saxon Chronicle – it has already become a concept not a text – was arrived at in the last years of King Alfred's reign, as a record of the victory over the Danes and the beginnings of a true national state. This relies on the fact that the 'A' manuscript is written up to the year 891 in one hand. Alternatively, did Alfred issue instructions, say, in the year 890, for a record of his deeds and those of his ancestors to be created for posterity, with continuous circulation of authoritative supplements – 'bulletins' is the term Professor Swanton uses – to keep all copies up to date and all in line? Or did one man in Winchester, like the later monk in Peterborough, simply copy out a good deal of pre-existing and perhaps heterogeneous material, and cast it onto the waters of chance?
This gives a glimpse of the problem, but the true situation is almost unimaginably more complex. There are five major manuscripts in Old English. Several Latin histories, however, clearly borrow from manuscripts of the same type, though none of these authors seems to have consulted any of the manuscripts that still exist. Each of the five manuscripts, whatever the number of the scribes who copied them and the unity or otherwise of their handwriting, is the product of many different annalists writing over a period of two to three hundred years. In general outline and particular wording they are very like each other – if they were not no one would ever have thought to call this composite 'the' Chronicle – but almost no year annal of any importance is identical to all its other versions.
The 'A' manuscript of the annal of 878 says: 'And that same winter a brother of Ivar and Halfdan was in Wessex in Devonshire with 23 ships, and he was killed there and 800 men with him and 40 men of his war-band.' The 'E' manuscript adds: 'and there the banner which they called "Raven" was taken.' In the Annals of St Neots is a long paragraph to the effect that the Raven Banner was woven within one night by the three sisters of Hynguar (or Ivar), and that it predicted victory by flapping its wings, defeat by hanging motionless. 'B', 'C' and 'D', like 'E', mention the banner, but Asser's Life of Alfred and the Chronicon of Æthelweard, an 11th-century alderman, reveal no more about the unnamed brother of Ivar than 'A' does. Does that prove that an addition was made to a lost copy of the Chronicle written after 'A' and copied into 'B', 'C', 'D', 'E' and St Neots? Or was the magic banner there all along but accidentally deleted? Alternatively, was the author of St Neots using a different source: the proto-saga in Old Norse about the descendants of Ragnar Hairy-Breeks, which survives as two late texts as well as a famous poem?
Every fact about the Chronicle seems to promise a revelation about its origins, which then trickles away in a dozen dispersing streams of doubt. Æthelweard's Chronicon preserves a sentence missed out of all versions of the Chronicle's annal for 885 – obviously by eye-skip, so Æthelweard must have had a prime original version! No, he mustn't: he could have had a later copy revised and updated. The 'B' manuscript ends with the words 'then he [King Edgar] died, then Edward, Edgar's son succeeded, and held' – the sentence breaks off with room still available on the page. That shows – doesn't it? – that this text was written after 8 July 975, the day Edgar died, and before Edward was murdered on 18 March 978: the annalist knew Edward was king but didn't know how long he would live. Not at all, Professor Janet Bately replies: it would be very unusual for an annalist to start reckoning the lifespan of a young king as soon as he'd succeeded. More likely, the text was written after Edward was known to have been murdered, and the annalist left a blank because he had not yet checked the exact duration of his reign.
As the data and the cross-references multiply like snarls in a ball of string, the hypotheses of origin become more complex. Janet Bately's stemma needs a minimum of eight hypothetical manuscripts to explain the five-plus we in fact have. Audrey Meaney has six and Charles Plummer about eight, though he does not reduce his theories to a diagram. All those stemmas, though different, do at least look like each other and all start off from the Alfredian initiative and dispersion. Cyril Hart, by contrast, offers a much more economical thesis, which drops King Alfred and proposes instead that the Chronicle didn't begin to be disseminated till more than a century later.
This inability to decode or unscramble the chain of transmission of a well-known and by no means hopelessly over-recorded text does look like a failure of technology. Printed texts destroy information: however elaborate their apparatus, they make it impossible to see where handwriting changes, where an author is evidently squeezing words onto the page or leaving blanks, where elaborate capitals have been inserted or where annal numbers have been written, perhaps by guesswork, into the margin of a continuous text. Moreover, even major research libraries cannot provide clear texts, edited according to identical principles, of all the Chronicle manuscripts. It often seems that the only way to make much sense of the way the manuscripts differ would be to get all of the originals together, lay them out on the floor and crawl from one to the other trying to see what their scribes have done. An alternative research strategy is that of the 'Collaborative Edition' of the Chronicle launched by Boydell and Brewer in 1983, and projected to run to 23 volumes, of which six have appeared, with five more in the pipeline.
But maybe print is just not the medium for this pre-Modern/Post-Modern Platonic idea of a document? Maybe instead the Chronicle has always been crying out (silently) to be a hypertext? Certainly, even more attractive than the crawl-round-the-floor method, would be to have every manuscript edited electronically, with all the suppressed information of printed texts available on sidebars, and the ability to 'toggle through' from one text to another, setting annal against annal and phrase against phrase at the touch of a key. Nice idea. But would it work? And would it be the empowering and liberating experience which technophiles promise? Some say that hypertext is an even more insidiously imprisoning technology than print: with it, you are under the control of the designers of the software and what they decide to be relevant, and are even less likely to notice it than you are to notice the results of editorial decisions in printed texts. Be that as it may, there is, as yet, no hypertext Chronicle.
The more important reason for taking an interest in The Anglo-Saxon Chronicle is that it is, to quote Swanton's Introduction to this new Everyman translation, 'the first continuous national history of any Western people in their own language'. It is the major source of information about pre-Conquest England; it is fascinating linguistically and stylistically; and it is different. Unlike the Latin Frankish chronicles, with their everlasting victories of the supradictus praeclarus rex against the Saxons (so often belied by the fact that he has to go back and repeat them next year), the late ninth-century Chronicle tells a grim, laconic, credible story of misunderstanding, disobedience and determination muddling through to a messy draw: an account that seems closer to Dark Age realities than any other surviving text. The shire aldermen do not obey their orders; vital forts are left ungarrisoned; relieving armies turn up too late; besieging armies bloody-mindedly raise the siege and go home because – and this is just the point where the original handwriting of 'A' stops – 'they had completed their call-up, and had used up their food.' At the same time, some things work. The English develop an 'army in being' strategy: don't fight the Vikings, hang off them in force so they daren't leave their ships unguarded. They try a 'scorched earth' policy and river-blocking; they try to challenge Viking supremacy at sea by building bigger ships to offset less competent sailors. The Vikings respond by changing their strategies, too: 'they went through the forest in gangs and mounted groups, on whichever edge was without an army, and almost every day they were sought by other groups both from the army and also from the strongholds, either by day or by night.' 'B', 'C', and 'D' take the second 'groups' in that sentence to mean 'peoples' or 'armies', a sensible statement but one which fails to get the immediate tactical point of (in modern terms) small-scale patrolling to dominate no man's land. The 'A' manuscript more relevantly and less predictably reads floccum not folcum, 'flocks' not 'folks', or 'platoons' rather than 'battalions'. On the other hand, both 'A' and 'B', unlike 'C' and 'D', have missed out the words 'either by day', though they are demanded by the context. Even the earliest copyists, it seems, had trouble with a text so little like any other and so unconditioned by Latin convention.
It is not surprising, therefore, that modern histories of the period often offer little more than a glossed text of the Chronicle. It tells a story we can understand. But perhaps this is a product of deliberate art rather than naive recording? Few suggestions have caused more historical fury in recent years than the argument that the Alfredian ninth-century annals are propaganda, written under the King's direct control if not by the King himself, to set out as established fact the aims of the Wessex dynasty. No other English king has any legitimacy (the Mercian king is just a 'foolish king's thegn' and a Viking puppet). No other member of the Wessex dynasty has any legitimacy (Alfred's elder brother's son Æthelwold is a traitor; Alfred's own son Edward gets no credit from the Chronicle for the victory at Farnham till his father is dead, only to be written back into the story years later by Æthelweard, a descendant of the traitor; Alfred's daughter Æthelflæd is mentioned by 'A' only when she dies, though 'C' and 'D' make it clear that she fully merited her title 'Lady of the Mercians'). Alfred's statesmanlike diplomacy is completely successful, except for one outburst of indignation from the 'A' chronicler which gives the game away. These queries make the Chronicle more interesting and potentially more valuable for historians, the ripples on the water hinting at powerful cross-currents underneath. Manuscript variation can expose contradictory opinions and Anglo-Saxon party politics, especially as the Chronicle moves on to the tenth and 11th centuries, as Scandinavian factions develop to match the English ones; as partisan chroniclers write irreconcilable accounts of the same event; and as one chronicler at least gives up in despair and writes an account of the years of Æthelræd's reign which has for ever confirmed his nickname of Unræd, 'Unready' or, more accurately, 'No-Idea'.
The Chronicle is, then, a vital and compelling text, made more so by its composite nature. But how is this to be conveyed? Plummer edited Two of the Saxon Chronicles Parallel with Supplementary Extracts from the Others, basically 'A' and 'E' on facing pages. A similar if more complex layout was used by Dorothy Whitelock in her English Historical Documents of 1954-5; her and Susie Tucker's Chronicle translation from that work was revised and reissued separately in 1962. It has long been unavailable, and Garmonsway's Everyman translation of 1953 simply follows Plummer, from the last century. A new translation which made the work more accessible and took account of modern discussion would therefore fill a gap, at least till the hypertext revolution comes: this is what Swanton has tried to provide.
The layout remains the familiar one of facing pages with inserts. On pages 60-1, for instance, we have 'A' facing 'E' for the years 817-29; the two chronicles are almost identical. Pages 90-1 are almost entirely from the long and detailed account of 896 in 'A', with mere inserts recording Alfred's death in 899 from 'D' and 'E'. Thirty pages later, the 'Death of Edgar' poem from 'A' faces what may well be a retrospective account written years after 975 by Archbishop Wulfstan from 'D', with a simpler version (the original or an abbreviation?) in 'E'. Another 30 pages on, Æthelræd's son Edmund Ironside is fighting King Canute in 'D', 'E' and 'F', and 30 pages later still, the contending chroniclers of 'C', 'D', 'E' and 'F' nevertheless agree in recording the refusal of loyal and rebel Englishmen alike to 'fight against men of their own race'. One can see that the internal variety of the Chronicle is getting fair treatment, and the prose translation is clear and consistent, the latter a valuable quality when one is dealing with variant texts. It may seem needlessly fussy always to translate here as 'raiding-army', even when it obviously indicates the East Anglian defence forces only. But then 'F' uses here while 'E' sticks to fyrd: it may mean nothing, or be a simple mistake, but trivialities in the Chronicle often turn out to be relevant.
The translator remarks wrily in his dedication to 'the saints and demons of the word processor' that 'while to err may be human, to really louse things up it takes a computer.' I can understand what he means: it would not be too difficult a business to hand-write a multiple translation with the approximate layout of one's final printed text, but given the ability of word processors invisibly to shift you onto another page while you think you're still writing a footnote, or to change the pagination at the speed of light (but not your internal references to it), I cannot imagine how a text like this could be written on a word processor, or successfully transferred from that to print. And though it has been done, there is a price. In particular, the bibliography – full though it is of both up-to-date and highly recondite material, especially on archaeology – contains no mention of several of the major discussions of Chronicle origins. Bately's Texts and Textual Relationships is there, but not her 'Manuscript Layout'. Hart's two volumes of Early Charters are there, but not his cat-among-the-pigeons 'B Text'. No work by Audrey Meaney is mentioned, nor is Swanton's major predecessor, the Whitelock and Tucker translation of 1962. One can probably see how this happened, for the bibliography 'is confined to references used in footnotes', and does not take in material used in the Introduction. Was Swanton using, to build his bibliography, some kind of tagging program for footnote references, deciding eventually not to interleave his Introduction references? Did he perhaps then have to cut down his Introduction, so that vital discussions – the first and most obvious things one would normally think of including in a bibliography – wound up falling between the editorial or electronic cracks? Some such explanation seems the likeliest, and if true it provides some excuse for omissions (and errors) which shrink the value of what will probably be for decades the most accessible modern version of the most important early vernacular European historical text.
In contrast to manuscript, print standardises and so destroys information; in contrast to both print and manuscript, the word processor eases and disguises revision. As one of Swanton's many interesting plates shows, any fool can see when a manuscript chronicler is writing in an afterthought. But a word processor smoothes it over 'swa heo no wære' ('as if it had never been'), even faster than the Peterborough chronicler. So mistakes are made which no one would make with simpler technology. In the dark all cats are grey, and all floppy disks look the same, whatever their contents. Scholars need to learn new protocols of care for Post-Modernity.
Vol. 19 No. 6 · 20 March 1997 » Tom Shippey » Not so much 'Unready', more 'No-Idea'

redpajama_set_name: RedPajamaCommonCrawl


More than 800,000 young immigrants who came to the US as children benefited from the DACA program.
The Donald Trump government on Monday called on the Supreme Court to accelerate the decision that has pending on DACA, the program with which the Democrat Barack Obama protected from deportation to tens of thousands of undocumented youth living in the United States since childhood.
The petition came on the eve of midterm congressional elections on Tuesday in the United States, where Democrats have options to regain at least control of the House of Representatives.
Trump has agitated the fear of immigration in this campaign and has placed the issue at the center of the debate with the caravans of migrants who advance through Mexico to the United States to request asylum.
The Trump administration canceled DACA in September 2017, but three federal judges later stopped that cancellation while the complaints against the government action that were filed in lower courts were settled.
A panel of three judges from the Ninth Circuit Court of Appeals already heard the arguments in this case in May, but for the time being it has not made any decisions.
The Trump administration now wants the Supreme Court to take it without waiting for that lower instance. Right now, conservative judges in the Supreme Court are more than progressives.
The Supreme Court, based in Washington, rejected in February unanimously its members to review the case of DACA with a quick procedure, as the Trump administration had already requested.
When the Ninth Circuit Court of Appeals, considered progressive, heard arguments in May on the issue, the Government said that if it had not made a decision by October 31, it would go to the Supreme Court.
DACA was approved by Obama in 2012. It has given temporary residence and works permits to nearly 800,000 undocumented youths known as "dreamers" (dreamers), who are 80 percent Mexican.
Trump's government canceled it under the argument that Obama overreached his presidential powers by assuming an issue that corresponds to Congress. But the blockade of a federal judge in San Francisco and another in New York kept the program alive while the lawsuits against the administration are being decided.
One of them was presented a year ago by several institutions and federal states, including California.
Trump even offered to legalize the situation of 1.8 million young people – more than double of those who have become enrolled in DACA – and even open the door to obtain US citizenship 10 or 12 years later in exchange for 25,000 million dollars for the wall on the border with Mexico and to increase the deportations of the rest of the undocumented.
The Democrats refused, but the issue also caused discomfort in the Republican ranks, where there are representatives who are in favor of immigration reform that allows young people to continue in a country where they have grown up and consider theirs.


Is it Easy to Finalize a Divorce?
Read more: Is it Easy to Finalize a Divorce?
A Divorce is not easy to finalize in California. There are many reasons for this. For one, the paperwork needs to be done correctly and be consistent. If there are errors or inconsistencies, the courts will reject the petition and you may have to start all over again. The courts may also require an amendment to the petition depending on the errors. The second reason is that the process is difficult and very exacting. If the correct copies are not sent or the paperwork is not within the time alloted or not in the right order, then the courts may also reject the paperwork.The best way to begin a Divorce is to speak with an experienced Divorce Lawyer who can advise you and explain the process.
Legal Action Workshop offers you Attorney advice and oversight and handles the processing of the Divorce paperwork in the court.


text:
Marconi News
Internet Pioneers and Leaders Tell the FCC: You Don't Understand How the Internet Works
Internet creators and leading figures ask the FCC to cancel its vote repealing Net Neutrality protections The Honorable Roger Wicker Chair, Senate Commerce Subcommittee on Communications, Technology, Innovation, and the Internet The…
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Building Tomorrow's Wireless World
2018 is already shaping up to be the year of wireless. 5G is all the rage, from skepticism about the economic viability of scale deployment to the inevitable technology showcase at the Pyeongchang Olympics in February. As a key component…
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Marconi Fellows Vint Cerf and Bob Kahn Receive 2018 Franklin Institute Awards
The Franklin Institute is pleased to announce The Franklin Institute Awards Class of 2018! We hope you will join us in congratulating our newest laureates for their remarkable achievements during The Franklin Institute Awards Week, scheduled…
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Aakanksha Chowdhery, Marconi News, Paula Reinman
The Smart City Edge
By Paula Reinman Co-authored by Dr. Aakanksha Chowdhery Smart cities are all the rage. From Alphabet's Sidewalk Labs turning Toronto's eastern waterside into a smart neighborhood pilot to Barcelona's superblock by superblock plan,…
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Marconi News, Paula Reinman
From the Marconi Symposium: A New Imaging Paradigm for the Age of Visual Information
By Paula Reinman In early October, the Marconi Society honored Marconi Prize winner Arun Netravali with a Symposium focused on digital video, hosted by Nokia Bell Labs. Shree Nayar, The T. C. Chang Professor of Computer Science at…
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Marconi News, Robert W. Lucky
The Lure of a Fully Decentralized Internet
By Robert W. Lucky. From the IEEE Spectrum. There are pros and cons, but let's be honest—decentralized technologies are just more fun In the most recent season of the TV comedy "Silicon Valley," lead character Richard Hendricks is…
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Marconi Society Chair Vint Cerf's Take on Steve Crocker's Tenure at ICANN
From Net Policy News Term limited. Steve writes, We have term limits for directors, no more than three consecutive three year terms. I have reached my limit and am leaving the Board. The Board's chair is chosen each year by the Board.…
http://marconisociety.org/wp-content/uploads/2017/09/Crocker_filtered.jpg 600 900 John Verducci http://marconisociety.org/wp-content/uploads/2016/01/Marconi-Web-Logo-2-2.png John Verducci2017-09-14 13:39:262017-09-14 13:39:26Marconi Society Chair Vint Cerf's Take on Steve Crocker's Tenure at ICANN
Why the Smart Home and Smart Enterprise Are More Connected Than Ever Before
Your smart home could be the site of the next organizational data breach, which is why there has never been a better time than now to mitigate IoT risk. By Ofer Amitai, OIT Journal Imagine: You're sitting at home on a conference call…
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News Release, Vinton G. Cerf
ConversatioNIST: The Internet and Cybersecurity
Donna Dodson, Associate Director and Chief Cyber Security Advisor, and Vint Cerf, Chief Internet Evangelist for Google and former NIST VCAT member, have a wide-ranging discussion about the past, present and future of the internet, network security,…
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Marconi News, Vinton G. Cerf
The Ethics of the Internet of Things Ecosystem
By Vint Cerf I've written on this topic before, mostly in the context of the Internet. I would like to focus now on products and services developed by engineers. "Ethics" is derived from the Greek ethos, which is defined as the characteristic…
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5G Fellows GPS Innovation Internet and Internet of Things Security Wireless Young Scholars
Digging Into Diversity, Inclusion and EthicsJune 21, 2019 - 8:17 am
Building the Sustainable Internet with a Spirit of CooperationJune 20, 2019 - 1:06 pm
Welcoming Our 2019 Marconi Fellows and Young ScholarsMay 21, 2019 - 2:54 pm
Networks to Support First RespondersApril 18, 2019 - 5:52 pm
Wireless Communication and Applications Above 100 GHz: Opportunities and Challenges for 6G and BeyondApril 11, 2019 - 4:12 pm
A New Day for Cryptography: Enabling Blockchain and CryptocurrenciesMarch 15, 2019 - 6:07 pm
Storage Meets DNA: How to Fit a Data Center into a ShoeboxFebruary 21, 2019 - 8:53 am
Happy 30th Anniversary, GPS and Thank You, Brad ParkinsonFebruary 11, 2019 - 11:31 am


Moshe Schnitzer, 82, former chairman of the Israel Diamond Institute, was recently awarded the Israel Prize, Israel's highest honor, for "making a special contribution to the State of Israel and Israeli society"—particularly his role in turning Israel into one of the world's leading centers for diamond manufacturing.
This is the first time the award has been given to a diamantaire. Schnitzer received the award at an official ceremony on Israel Independence Day on April 26.


All Police Officers in England and Wales are bound by the Police and Criminal Evidence Act 1984 Codes of Practice – sometimes referred to as PACE or the PACE Codes of Practice.
This App contains the latest version of Codes A to H having broken them down into individual Codes, sections, paragraphs, notes for guidance and annexes.
As well as being able to find a paragraph by Code and Section there is also a very detailed index so you can search for all paragraphs that contain a specific word or words.
When a paragraph is displayed which has a reference to another paragraph then the reference is listed under a 'see also' heading and clicking on the reference will take you to the paragraph in question.


text:
5 Highest Paid Colorado State University Employees
Jacob Laxen
Jacob Laxen Published: February 3, 2021
For more than 150 years, Colorado State University has been key to the identity of Fort Collins.
The University established in 1870 has evolved from being known as Colorado Agricultural College and Colorado A&M.
CSU now employs more than 7,000 people — The Coloradoan tracks all employee salaries in an online database as part of its government accountability mission.
Like many universities around the country, CSU's athletics department dominates the top of the pay grade.
Here are the five highest paid employees currently at CSU:
5 Highest Paid CSU Employees
Athletics aren't just paid a premium in Fort Collins. At the University of Colorado, football coach Karl Dorrell makes a base salary of $3.2 million. Buffaloes basketball coach Tad Boyle makes $1.5 million.
University of Colorado president Mark Kennedy makes $850,000.
Some university presidents around the country are now making more than $1 million annually. University of Texas president William H. McRaven makes $1.5 million a year and Ohio State University President Michael V. Drake makes $1.07 million, according to media reports.
5 Kickass Females You Didn't Know Went to CSU
CSU Rams Fans Through the Years
Categories: CSU Rams Sports, List Galleries, Sports
Spend the Day in Sedalia, Colorado: What to See and Where to Go
Colorado Eagles Fight Cancer Weekend Was Amazing. See the Pix
New Study Names Colorado's Ugliest City — But You Say These Towns Are Uglier
10 Fort Collins Date Ideas That Are Perfect for Valentine's Day
Go, Rams: 3 Big CSU-Related Highlights From Early January 2023
Will The Broncos Suck Again Next Season? Here's Who's Coming To Mile High
Colorado Wagers: How Our Sports Betting Stacks Up to Other States
Will Empower Field at Mile High Be Next to Get a Section Yellow?


CONTACT FOR MORE INFORMATION OR PHOTOS! So just be little patient, all depends on post-office. DUBLICATE GLORY ORDER SET USSR SOVIET RUSSIAN ARMY WW2 WAR AWARDS GROUP" is in sale since Friday, October 12, 2018.
This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Russia\Medals, Pins & Ribbons".armenia" and is located in Yerevan, Armenia. This item can be shipped worldwide.


text:
Q: How can I set the value of a dropdownlist according to the action of another dropdownlist? I am a beginner in C# and asp.net.
In my work , a particular webform consist two dropdownlist whose IDs are respectively "DepartFrom" and "DepartTo". Each list consist the same text items. Texts are "Dhaka, Chittagong, Sylhet, Cox'sbazar".
Now I want to action as follows :

*

*When I select "Dhaka" in "DepartFrom" list it will not appear in the "DepartTo" list, but the others will.

*When I select 'Text' except 'Dhaka' in 'DepartFrom' list, only 'Dhaka' will appear in the "DepartTo" list.

I have tried this but it's not working.
`protected void Page_Load(object sender, EventArgs e)
        {

                if (DepartFrom.Items.ToString() == "Dhaka")
                {
                    DepartTo.Items.Clear();
                    DepartTo.Items.Add("Chittagong");
                    DepartTo.Items.Add("Cox'sbazar");
                    DepartTo.Items.Add("Sylhet");
                    DepartTo.SelectedIndex = 0;
                }

                else
                {
                    DepartTo.Items.Clear();
                    DepartTo.Items.Add("Dhaka");
                    DepartTo.SelectedIndex = 0;
                }

        }
`

Can anyone help?

A: You can set AutoPostBack="true" to your dropdownlist who define behavior of second dropdownlist, and also define SelectedIndexChanged event on this dropdownlist
asp:DropDownList ID="DepartTo" runat="server" AutoPostBack="True"
        onselectedindexchanged="itemSelected">
    </asp:DropDownList>

Code Behind
protected void itemSelected(object sender, EventArgs e)
{
   var control = (DropDownList)sender;
   if(control.SelectedValue == "")
   {
     .....
   }
}

A: Here is a long but easy to understand way:
<asp:DropDownList ID="DepartFrom" runat="server" AutoPostBack="True"
        onselectedindexchanged="fromSelected">
    </asp:DropDownList>

<asp:DropDownList ID="DepartTo" runat="server">
 </asp:DropDownList>

Code Behind.
string[] items={"Dhaka", "Chittagong", "Sylhet", "Cox'sbazar"};
protected void fromSelected(object sender, EventArgs e)
{

 if((sender as DropDownList)!=null)
  {
   DepartTo.Items.Clear();
   foreach(string str in items)
    {
       if((sender as DropDownList).SelectedItem.ToString()!=str)
       {
        DepartTo.Items.Add(str);
       }
     }
   }

}

redpajama_set_name: RedPajamaStackExchange


I'm getting braces in early February, and I have two questions about them.
I heard you can get different colours, what colour should I get?
I'm not gonna lie, braces really hurt for the first week or so. It's because your teeth are moving. So when you get them tightened or get a chain or elastics, they'll hurt for the first few days. But other than that they aren't as cumbersome as some make them out to be Just remember to brush your teeth really good, 'cause braces make it really hard to keep your mouth clean sometimes.
I used to have braces, I always loved changing the colors. Some of my favorite color combinations were pink & purple, teal & purple, teal & pink, bright green & teal. Sometimes what I did was since you get the colors changed every month, I went along with the holiday. So since you are getting them on in February I would pick pink & red.
Good luck It's really fun picking out colors every month!!
Ooh, pink and red is a good idea! I'm actually pretty excited now to get my braces, just so I can pick those colours.
That stinks that they hurt. But it will make my teeth look nice, and it doesn't sound like it hurts for too long. Thanks for the advice!


text:
Канкер () — округ в индийском штате Чхаттисгарх. Образован в 1999 году из части территории округа Бастар. Административный центр — город Канкер. Площадь округа — 6506 км². По данным всеиндийской переписи 2001 года население округа составляло 650 934 человека. Уровень грамотности взрослого населения составлял 72,9 %, что выше среднеиндийского уровня (59,5 %). Доля городского населения составляла 4,8 %.

Округа Чхаттисгарха

redpajama_set_name: RedPajamaWikipedia


Repurposing is the best! Take an old door and turn it into a hallway mantle to get the most beautiful entryway on the block. Old doors are easy to come by and depending on the type you snag you can have a mantle picture frame, coat hanger, shelf, or a mix of all three.


text:
https://doi.org/10.1140/epja/s10050-022-00904-6
Activation cross-sections of proton induced reactions on natural molybdenum within 75–100 MeV
H. Sun1,2,3, B. Liu1,3, R. Han1,2,3, Z. Chen1,2,3d, G. Tian1,3, F. Shi1,3, Z. Zhang1,2,3, B. Yang1,2,3 and P. Luo1,2,3
1 Institute of Modern Physics, Chinese Academy of Sciences, 730000, Lanzhou, China
2 School of Nuclear Science and Technology, University of Chinese Academy of Sciences, 100049, Beijing, China
3 Advanced Energy Science and Technology Guangdong Laboratory, 516000, Huizhou, China
d zqchen@impcas.ac.cn
Accepted: 9 December 2022
Experimental cross-sections for the nuclear reactions Mo(p,x) Tc, Mo, Nb and Zr were measured up to 100 MeV, carring out at separated sector cyclotron of the Heavy Ion Research Facility in Lanzhou, using the stacked-foil activation technique. The cross-sections of these nuclides in this work fill the gap in 75–100 MeV energy range. In addition, our experimental results were compared with the previously published values taken from EXFOR database and the theoretical calculations predicted by TALYS-1.95 code with six level density models, which are important input parameters affecting the excitation functions. In terms of results, our measurements show good agreement with the theoretical calculations for most of the radionuclides. Level density models still needs to be further optimized in the description of excitation functions.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
New measurement of residual cross sections from Nb reaction: a comparative study of PEQ models and nuclear level densities
Measurement of alpha-induced reaction cross-sections on Mo with detailed covariance analysis
Measurement of isomeric ratios for 89g,mZr, 91g,mMo, and 97g,mNb in the bremsstrahlung end-point energies of 16 and 45-70 MeV
A study of pre-equilibrium emission of neutrons in 93Nb(α, xn) reactions
Eur. Phys. J. A (2007) 31: 43-51
Excitation functions for the formation of Nb, Nb and Nb in the Zr(p,x) reactions


The "Optical Coherence Tomography market" report provides an organized picture of the market by the method, combination, and summary of study and information gained from different sources. The Optical Coherence Tomography market report likewise comprises a complete market and vendor scenario aside from a SWOT analysis of the major players Carl Zeiss Meditec AG, Agfa Healthcare, Imalux Corporation, Heidelberg Engineering GmbH, OPTOPOL Technology S.A., Michelson Diagnostics, Novacam Technologies Inc., Optovue, Topcon Medical Systems Inc., Thorlabs. Hence, the data provided is wide-ranging, consistent, and the result of extensive research.
The Optical Coherence Tomography market report provides a pinpoint analysis of competitive dynamics that are changing and puts you ahead of competitors. In addition, the report is also designed with the forecast for CAGR (Compound Annual Growth Rate) for the Optical Coherence Tomography market in the rate of % for the specific time span.
The report presents a detailed segmentation Catheter-Based OCT Devices, Doppler OCT Devices, Handheld OCT Devices, Tabletop OCT Devices, Market Trend by Application Ophthalmology, Cardiovascular, Oncology, Dermatology, Other of the global market based on technology, product type, application, and various processes and systems. Apart from this data, the report also provides chief challenges, forthcoming market momentum, and scope in the Optical Coherence Tomography market. This report states each point of the international Optical Coherence Tomography market, preliminary from the fundamental market information and moving ahead to different criteria based on which the global market is categorized. The chief application areas of Optical Coherence Tomography market are also covered based on their implementation. The report gives the idea about different factors and trends influencing the development course of the global Optical Coherence Tomography market. An assessment of the impact of government regulations and policies on the Optical Coherence Tomography market operations is also comprised in this report.
The characteristics and performance of the Optical Coherence Tomography market are analyzed based on the qualitative and quantitative method to give a transparent image of the present and future forecast trend. An accurate geographical analysis of the Optical Coherence Tomography market has also been done in this report. The Optical Coherence Tomography market report is well-organized with graphs, figures, and facts which demonstrates the status of the particular industry on the regional and international platform.
Chapter 13, 14 and 15, Optical Coherence Tomography sales channel, distributors, traders, dealers, Research Findings and Conclusion, appendix and data source.


My 2.5 year old son loves to play make believe games. One of his favourites is to be a knight on his horse or a Viking chasing dragons. I'm not sure Vikings really chased dragons but he has a great time pretending anyway.
Today he asked me for a shield which could be used if he was a Viking or a knight in shining armour. Instead of buying another piece of plastic, I decided we would make one together. Armed with what we could find in the house, this is what we created.
First cut up your egg box. The pieces will be used to create a relief on the shield to give it depth and texture. The number of pieces you cut will vary on the size of your plate.
Use sellotape to attach your egg box pieces to the plate. It doesn't need to look neat as this will all be covered up. Try not to have the pieces stuck too close together as it makes it harder to cover later.
Use a piece of kitchen foil which is larger than your plate. It needs to be big enough to cover the front, go over your egg box pieces and wrap around the back a little.
Gently place the kitchen foil over the front of your plate and squish around the egg cup pieces. Once it's generally over, you can then start to smooth it down. If you have some detailing around the edge of your paper plate, run your thumb over firmly and it will bring out the pattern through the foil.
Wrap the excess foil around the edge of the plate to the back.
Cut a length of cardboard, so it's long and thin to make a handle. Fold over the ends and secure with tape to the back of your shield. Your simple handle has been created.
Your shield is now ready for action. My son told me that he was going to use it to protect his baby brother from the dragons. I have a feeling I'm now going to be challenged with creating a helmet and full outfit but hopefully this will keep him occupied for now.


text:
De alaskafluithaas (Ochotona collaris)  is een zoogdier uit de familie van de fluithazen (Ochotonidae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door Nelson in 1893.

Verspreidingsgebied
De soort wordt aangetroffen in Canada en de Verenigde Staten.

Fluithazen
Dier uit het Nearctisch gebied
IUCN-status niet bedreigd


A tale of romance set in the packing department of a 1988 factory.
A short play performed at The Vaults with The Pensive Federation, April 2018.
Directed by Neil J. Byden. Starring Joanna Pope, Samuel Treharne and Isabel Crowe.


text:
\section{Introduction}
\label{sec:intro}
Vapor-cell atomic clocks provide excellent frequency stability together with low volume and power consumption. They are employed both on ground and in space applications~\cite{Riley2019}. Laser-based devices, working either with continuous or pulsed schemes, have shown state-of-the-art stability levels in their class, making them attractive options for next generation global navigation systems~\cite{Godone2015,Camparo2015,schmittberger2020}. Several industries have shown increasing interest for the pulsed optically pumped (POP) Rb clock, in virtue of its demonstrated performances and mature technology~\cite{Arpesi2019}.

For industrial and spaceborne applications, a compact and light physics package is of high importance, not only for weight and volume considerations, but also for the possibility to reduce the overall power consumption and to improve the mechanical design. Moreover, for space applications, the mid and long-term stability is of greater relevance than having state-of-the-art short term performances ($\simeq$\num{1.5e-13}$\,\tau^{-1/2}$)~\cite{Micalizio2012a,Bandi2014}. The development of a  compact physics package goes in this direction, providing easier temperature stabilization and mitigation of temperature gradients, compared to a distributed object. This results in foreseen improved mid-term frequency stability performances~\cite{Hudson2018}.

This work presents a miniaturized microwave cavity suitable for POP~\cite{Micalizio2012} or continuous-wave~\cite{Bandi2014} Rb clocks, looking for a trade-off between physical dimensions and desired short-term stability performances.

The physics package of Rubidium standards typically presents a layered structure, including several layers of magnetic and thermal shields. To reach an overall reduction the package size, the most efficient strategy is to reduce the volume of the physical core of the clock, i.e. the microwave cavity. Many high-performing clocks make use of a cylindrical cavity resonant on the $\mathrm{TE_{011}}$ mode, because of its favorable $\mathbf{H}$-field distribution, which is uniform and parallel to the cavity axis in the central region of the cavity. This features guarantees to excite the clock transition in an efficient way, increasing the contrast of the clock signal~\cite{Godone2011}. The cavity inner dimensions are designed in order to tune the resonance frequency to the atomic clock transition (\SI{6.8}{\giga\hertz} for $\mathrm{^{87}Rb}$).

One way to shrink the cavity dimensions, keeping the magnetic field resonant with the atomic clock transition, is the use of a loop-gap resonator (also called ``magnetron'' or ``split-ring'' resonator)~\cite{Froncisz1982,Sphicopoulos1987}. This approach has been proven effective both for the continuous-wave and the POP rubidium frequency standards~\cite{Stefanucci2012,Kang2015,Hao2019}. Indeed, it provided reduction of the overall cavity-cell volume up to a factor 4.5, retaining comparable cell size and clock performances, compared to the traditional cylindrical cavity.

Inserting a dielectric material inside the cavity volume can also lead to remarkable volume reduction~\cite{Howe1983,Williams1983}. Dielectric loading can also be exploited, to some extent, to increase the field uniformity in the active volume~\cite{Mett2001,Wang2019}.

We propose a novel design solution for the cavity-cell assembly based on an alumina-loaded microwave cavity, demonstrating an external volume of only \SI{35}{\centi\meter\cubed}.
The loaded cavity still works on a $\mathrm{TE_{011}}$-like mode, ensuring favorable magnetic field uniformity and directionality. Such strong size reduction is possible by scaling also the clock cell, whose inner volume is reduced by a factor 8. As demonstrated in more detail in \Cref{sec:design} and \Cref{sec:exp}, this volume reduction partially affects the clock short-term stability, but still provides interesting performances.

The proposed alumina-loaded cavity offers new design alternatives and thus facilitates the use of the POP technology for in-field applications. Advantages of this approach is the notable size reduction and mechanical stability, as the dielectric can serve also as self-centering spacer for the clock cell.

The paper is organized as follows: in \Cref{sec:design} the proposed design is introduced. In \Cref{sec:FEM} the loaded-cavity main features are analyzed with the aid of Finite Element Method (FEM) analysis. Finally, in \Cref{sec:exp} the cavity is experimentally characterized, and foreseen short-term stability performances for such a cavity in a POP clock experiment are discussed.

\section{Cylindrical loaded-cavity design}
\label{sec:design}
Reducing the cell dimensions has two effects: first, it reduces the available atomic sample volume, thus decreasing atom number and the signal-to-noise ratio. Second, the atomic population relaxation rates are increased, due to the collisions with the cell walls. The first point is not critical for many laser-based vapor-cell clocks, since they are not limited by shot-noise, rather from laser intensity and frequency noises~\cite{Calosso2020}. The second issue can be mitigated by finding an optimal buffer gas pressure for which the total relaxation rate is minimized. Indeed, since for typical operational temperatures the main transverse relaxation-rate contribution is due to spin-exchange collision between Rb atoms, there is margin to increase the pressure of the buffer gas without significantly enhancing the total relaxation rate~\cite{Micalizio2009}.

Given the last considerations, for a traditional buffer-gas mixture composed of Ar and $\mathrm{N_2}$ (1.6:1 ratio)~\cite{Vanier1982}, the total buffer-gas pressure is set to \SI{40}{\torr} (\SI{53.2}{\hecto\pascal}). At this pressure, and for a typical operational temperature of \SI{62}{\degreeCelsius}, the transverse relaxation rate $\gamma_2$ is minimized ($\gamma_2\simeq\SI{400}{\per\second}$)~\cite{Vanier1989}. Compared to the case of a \SI[product-units = repeat]{2 x 2}{\centi\metre} cylindrical cell with \SI{25}{torr} of buffer gas ($\gamma_2 = \SI{280}{\per\second}$), this corresponds to a 1.4 factor increase in the transverse relaxation rate. The $\gamma_2$ rate causes a decay of the atomic signal, ultimately limiting the interrogation time length ($T\approx\gamma_2^{-1}$), so we expect the optimal Ramsey time to be reduced roughly by the same factor ($T\simeq\SI{2.4}{\milli\second}$ versus $T\simeq\SI{3.4}{\milli\second}$). Finally, a reduction of the interrogation time lowers the atomic line quality factor, impacting the short-term stability. We consider these values a reasonable trade-off between expected performance and physics package size reduction.
\begin{figure}
	\includegraphics[width=\columnwidth]{./Figure1.pdf}
	\caption{\label{fig:CAD} Rendering of the cavity-cell assembly (cross-section view).}
\end{figure}

The complete setup is shown in \Cref{fig:CAD}. The dielectric has a cylindrical shape, to preserve as much as possible the symmetry of the system. A small indent is introduced to allow the cell stem to exit the cavity volume (a cold point is desirable to induce metallic rubidium condensation outside the cavity volume). The alumina tube is centered with the aid of two Teflon rings that increase the mechanical tolerance. The cavity is made of aluminum and consist of a cylindrical body and two endcaps fixed by a set of screws. The end-caps of the cavity present two circular apertures, with \SI{9}{\milli\meter} diameter, for optical access. These apertures are followed by cylindrical wave-guides with the same diameter. With such a geometry, the $\mathrm{TE_{011}}$ mode frequency is below the waveguide cut-off frequency and power attenuation of at least 40 dB for the evanescent microwave field is obtained with a total waveguide length of \SI{12}{\milli\meter}, making the clock frequency instability due to microwave leakage negligible. Also in this case, the reduction of the cell size and, consequently, of the needed optical access allowed us to scale the waveguides volume, maintaining the same attenuation of the unloaded design. On one side of the cavity, a magnetic coupling loop (created with a short-circuited SMPM coaxial cable) provides the microwave excitation. The system is completed with a plano-convex lens which focuses the laser light onto a \SI[product-units=repeat]{2.6x2.6}{\milli\meter} Si photodiode.

\subsection{Finite element analysis (FEA)}
\label{sec:FEM}
The resonance frequency and spatial distribution of the cavity modes of interest are analyzed with the aid of the finite-element-method software tool CST-studio~\cite{CSTstudio}.

At first, the geometry of the cavity, cell and loading material are determined, so that the $\mathrm{TE_{011}}$-mode frequency matches the atomic frequency. A check of the nearest resonance modes is made, to verify that they do not overlap with the main cavity mode.

\begin{table}
\caption{\label{tab:modes} Resonance frequencies and $Q$-factor for the main cavity modes (without clock cell).}
\centering
\renewcommand{\arraystretch}{1.5}
\resizebox{0.49\textwidth}{!}{
	\begin{tabular}[]{l c c c c}
		\toprule
		mode  & $\nu_0$ (FEA)\footnote{Assuming conducibility of Al $\sigma = \SI{3.8e7}{\siemens\per\meter}$ } & $Q_i$ (FEA) & $\nu_0$ (exp.) & $Q_i$ (exp.) \\
		\hline

		$\mathrm{TE_{011}}$  	 & \SI{7.17}{\giga\hertz}    &	 5200  &  \SI{7.00\pm0.01}{\giga\hertz}	& $4000\pm200$ \\

		$\mathrm{TM_{111}}$  	 & \SI{7.58}{\giga\hertz}    &	 5100  &  \SI{7.50\pm0.01}{\giga\hertz}	& $3200\pm200$ \\

		$\mathrm{TM_{011}}$  	 & \SI{6.20}{\giga\hertz}    &	 4200  &  --	& --	\\
		\bottomrule
	\end{tabular}}
\end{table}

From the FEA analysis, given their spatial distribution, the two nearest modes are recognized as the $\mathrm{TM_{011}}$ and $\mathrm{TM_{111}}$. They lie at least \SI{400}{\mega\hertz} away from the eigenmode of interest for the clock operation. Conveniently, the dielectric loading completely lifts the degeneracy of the $\mathrm{TM_{111}}$ and $\mathrm{TE_{011}}$ modes, thus no mode-choke for the $\mathrm{TM_{111}}$ mode is necessary. In \Cref{tab:modes} a list of the simulated resonance frequency modes and relative intrinsic $Q$-factors (considering also the dielectric losses from the loading materials) is shown for the loaded microwave cavity without the clock cell. The simulated values are compared to the measured one. As it will also be noted in \Cref{sec:exp}, the discrepancy in the absolute frequency is mainly due to the value of the dielectric constant of the alumina at \SI{6.8}{\giga\hertz}, which resulted \SI{3}{\percent} higher than the value given from the manufacturer~\cite{morgan-datasheet}.

Second, the uniformity and directionality grades of the $\mathrm{TE_{011}}$ mode is evaluated. In particular a ``uniformity coefficient'', introduced in \cite{Godone2011}, is used to characterize the amplitude variations of the $H_z$ component over the active volume ($V_a$). To avoid ambiguity,	the latter is taken coincident with the cell inner volume. Compared to \cite{Godone2011}, the definition has been slightly modified to allow the maximum of the magnetic field to lie away from the center of the cavity (due to asymmetries in the cell and loading materials):
\begin{equation}
u = \frac{\frac{1}{V_a}\int_{V_a}^{}H_z(\mathbf{r})^2 \; dV }{\displaystyle\max_{\mathbf{r}\in V_a} \lbrace H_z(\mathbf{r})^2\rbrace}
\end{equation}
where $\mathbf{r}$ is the spatial coordinates vector. In this way \mbox{$0<u<1$}, with $u=1$ corresponding to a perfectly uniform field distribution.
Following \cite{Stefanucci2012}, we also report the ``orientation coefficient'' $\xi$, defined as:
\begin{equation}
\xi = \frac{\int_{V_a}^{}H_z(\mathbf{r})^2 \; dV }{\int_{V_a}^{} |\mathbf{H}(\mathbf{r})|^2 \; dV }
\end{equation}
This coefficient is a figure of merit of the orientation of the $\mathbf{H}$ field along the quantization axis $z$. A high orientation factor ($\xi$ close to 1), minimizes the excitation of the $\sigma$-transitions ($\Delta F=1$, $\Delta m_F=1$), that can cause unwanted cavity pulling on the clock transition~\cite{Gerginov2014}. For completeness, we also report the filling factor, which is mostly important for active oscillators (or POP with microwave detection~\cite{Godone2004}), expressing the degree of coupling between the microwave field and the atomic sample:
\begin{equation}
\eta'= \frac{\left( \int_{V_a}^{}H_{z}(\mathbf{r}) \; dV \right)^2}{V_a\int_{V_c}^{}|\mathbf{H}(\mathbf{r})|^2 \;dV}
\end{equation}
where $V_c$ is the inner cavity volume.
\begin{figure}[]
	\centering
	\begin{subfigure}[b]{0.3\textwidth}
		\centering
		\includegraphics[width=\textwidth]{./Figure2a.png}
		\caption{$\mathbf{H}$ field in the $y$-$z$ plane.}
		\label{fig:H}
	\end{subfigure}
	\hfill
	\begin{subfigure}[b]{0.3\textwidth}
		\centering
		\includegraphics[width=\textwidth]{./Figure2b.png}
		\caption{$E_x$ component in the $y$-$z$ plane.}
		\label{fig:E_x}
	\end{subfigure}

	\caption{Magnetic and electric field distribution inside the cavity volume for the $\mathrm{TE_{011}}$ mode.}
	\label{fig:FEM}
\end{figure}
In \Cref{fig:H}, the $\mathbf{H}$ field lines and amplitude for the proposed loaded-cavity assembly are shown in the \mbox{$y$-$z$} plane (the pumping/detection laser propagates along the $z$-axis). We can notice a rather good uniformity of the field component over the cell volume. We point out that along this plane we have the maximum field distortion due to the presence of the stem, while on the \mbox{$x$-$z$} plane we have better uniformity. Looking at the field lines distribution, we notice that a gap between the alumina tube and the cavity wall is not only preferable in terms of mechanical tolerances, but it also increases the mode uniformity. Indeed, due to the high dielectric constant of $\mathrm{Al_2O_3}$, the electric field is strongly concentrated inside the dielectric volume~\cite{joannopoulos2008} (see \Cref{fig:E_x}) and the magnetic field lines need a dielectric-free volume to concatenate the electric field lines.

In \Cref{tab:coefficients} the previously introduced coefficients for the proposed configuration are reported and compared to other cavity-cell assemblies present in the literature. We can observe that the uniformity is increased compared to the case of the traditional cylindrical cavity while the orientation is comparable to other kind of compact assemblies. Finally, the filling factor is reduced compared to the case of the unloaded cavity, reducing cavity-induced sensitivities such as cavity-pulling, but still high enough to provide sufficient coupling between the field and the atomic sample to achieve efficient clock interrogation. \\

\begin{table}[t]
	\caption{\label{tab:coefficients} Comparison of different published cavity-cell assemblies in terms of magnetic field uniformity and orientation. }
	\centering

	\renewcommand{\arraystretch}{1.5}
	\resizebox{0.4\textwidth}{!}{
		\begin{tabular}[]{l c c c}
			\toprule
				cavity type	&	$u$	&	$\xi$	&	$\eta'$	 \\
			\hline

			cylindrical~\cite{Godone2011,Micalizio2012}	&	0.59	&	0.92	&	0.38	\\
			magnetron~\cite{Stefanucci2012}	&	n/a		&	0.87	&	0.14	\\
			magnetron~\cite{Hao2019}		&	n/a		&	0.90	&	n/a		\\
			$\mathrm{Al_2O_3}$-loaded (this work)&	0.82	&	0.76	&	0.20		\\

			\bottomrule
	\end{tabular}}
\end{table}

\subsubsection*{Thermal sensitivity}
For clock applications, the stability of the cavity mode frequency is of paramount importance, as it can impact the clock frequency through cavity-pulling~\cite{Micalizio2009}. One of the main parameters of influence is temperature~\cite{Godone2011,Wang2019}, which can change the resonance frequency $\nu_c$ by thermal expansion and by affecting the dielectric properties of the materials.

The total contribution to the sensitivity of the cavity resonance frequency to a temperature variation $\Delta T$, for small variations from the operational setpoints, can be expressed as a sum of terms:
\begin{equation}
		\frac{1}{\nu_c}\frac{\Delta \nu_c}{\Delta T}  = \sum_{k}^{} \frac{x_k}{\nu_c} \frac{\Delta \nu_c}{\Delta x_k}   \alpha_k  + \sum_{i}^{}   \frac{\epsilon_i}{\nu_c} \frac{\Delta \nu_c}{\Delta \epsilon_i}  \beta_i
\end{equation}
where $x_k$ are the geometric dimensions of the cavity and loading materials and $\alpha_k = \frac{\Delta x_k}{x_k\Delta T} $ the corresponding linear thermal expansion coefficient;  $\epsilon_i$ is the dielectric constant of the $i$-th material inside the cavity and $\beta_i = \frac{\Delta \epsilon_i}{\epsilon_i\Delta T}$ the related thermo-dielectric coefficient.
\begin{table}[b]
	\caption{\label{tab:temp_coeffs} Major contributions to the cavity thermal sensitivity expressed in relative terms. The geometric and thermo-dielectric contributions are listed in the upper and lower part of the table respectively, in decreasing order of importance.}
	\centering

	\renewcommand{\arraystretch}{1.5}
	\resizebox{0.49\textwidth}{!}{
		\begin{tabular}[]{l c c c}
			\toprule
			\hline
			\addlinespace[2pt]
			 	$x_k$ contribution 		& \addstackgap[1pt]{ \large $\frac{x_k}{\nu_c} \frac{\Delta \nu_c}{\Delta x_k}  $ }	& $\alpha_k$ & \large $\frac{1}{\nu_c}\frac{\Delta \nu_c}{\Delta T}$ 	 \\
			 		&	& $(\si[per-mode=symbol]{\ppm\per\kelvin})$	& $(\si[per-mode=symbol]{\ppm\per\kelvin})$ \\
			\hline

			cavity radius				&	-1.04	&  23	&	-23.9	\\
			cavity length				&	-0.13	&  23	&	-3.0	\\
			$\mathrm{Al_2O_3}$ thickness&	-0.22	&  6.9	&	-1.5	\\
			$\mathrm{Al_2O_3}$ length	&	-0.07	&  6.9	&	-0.5	\\
			\hline
			\addlinespace[4pt]
			\hline
			\addlinespace[2pt]
				$\epsilon_i$ contribution 		& \addstackgap[1pt]{ \large $\frac{\epsilon_i}{\nu_c} \frac{\Delta \nu_c}{\Delta \epsilon_i} $ }	& $\beta_i$ &  \\
				&	& $(\si[per-mode=symbol]{\ppm\per\kelvin})$	&  \\
			\hline
			$\mathrm{Al_2O_3}$ 	&	-0.43	&  92	&	-39.7	\\
			fused silica		&	-0.03	&  10	&	-0.3	\\
			\hline
			\bottomrule
			\addstackgap[1pt]{\textbf{Total sensitivity}} &	&	& -69.0 \\
			\bottomrule
	\end{tabular}}
\end{table}

In \Cref{tab:temp_coeffs} the major contributions to the cavity frequency thermal sensitivity are expressed in relative terms. The sensitivity coefficients are taken from FEM calculations, that can provide a numerical evaluation of the mode frequency as a function of the various parameters. In \cref{fig:sweeps}, for example, the $\mathrm{TE_{011}}$-mode frequency is plotted as a function of the cavity length and radius.
\begin{figure}[]
	\includegraphics[width=\columnwidth]{./Figure3.pdf}
	\caption{\label{fig:sweeps} $\mathrm{TE_{011}}$ resonance frequency as a function of cavity length and radius, as derived from the finite element analysis. The red dashed line corresponds to the atomic frequency ($\SI{6.8347}{\giga\hertz}$). }
\end{figure}

Close to the working points, we find that the main contribution from variations of the geometric parameters is due to the cavity radius: $\frac{1}{\nu_c}\frac{\Delta \nu_c}{\Delta T} = \SI[per-mode=symbol]{-23.9}{\ppm\per\kelvin}$. The sensitivity to the cavity thermal expansion is -1.17, close to the case of the empty cylindrical cavity cavity (equal to \num{-1}). Given the low thermal-expansion coefficient of alumina ($\alpha_{\mathrm{Al_2O_3}} = \SI[per-mode=symbol]{6.9}{\ppm\per\kelvin}$)~\cite{morgan-datasheet}), the geometric contribution from the loading material is instead small ($\simeq \SI[per-mode=symbol]{-2}{\ppm\per\kelvin}$).

The other major contribution to the temperature sensitivity comes from the variation of the dielectric constant of the alumina. From the manufacturer's datasheet~\cite{morgan-datasheet} we extract a thermo-dielectric coefficient $\beta_{Al_2O_3} = \SI[per-mode=symbol]{92}{\ppm\per\kelvin}$, while from the FEM analysis we obtain a linear dependence of the cavity frequency on $\epsilon$, with slope $\frac{\epsilon}{\nu_c}\frac{\Delta\nu_c}{\Delta\epsilon} = -0.43$. This value is close to the case of a fully loaded cavity cavity (-0.5). This is expected, since the electric field is mostly concentrated in the dielectric volume. The contribution from the linear expansion of the fused-silica cell and effects related to the Teflon spacers are instead negligible ($<\SI[per-mode=symbol]{0.1}{\ppm\per\kelvin}$).

Summing up all terms, the cavity resonance sensitivity is expected to be: $\Delta\nu_c/\Delta T = \SI[per-mode=symbol]{-472}{\kilo\hertz\per\kelvin}$. The total sensitivity to temperature is higher than the one of the unloaded cavity by a factor 3, but considering the lower filling factor (and for a typical cavity detuning of \SI{500}{\kilo\hertz} and loaded quality factor $Q_L=2800$) we estimate an expected clock fractional frequency sensitivity to temperature of $\simeq\SI[per-mode=symbol]{5e-12}{\per\kelvin}$ from cavity-pulling effect~\cite{Micalizio2009}. A temperature control at the level of \SI{0.5}{\milli\kelvin} is thus sufficient to reach state-of-the-art stability performance. We remind that given the small size of the cavity, such a level of temperature stabilization is not hard to achieve.
\section{Experimental characterization}
\label{sec:exp}
The cavity-cell components are shown in \Cref{fig:photo} during the assembly phase. The cell used in the experimental validation is made of fused silica, with internal diameter and length both equal to \SI{1}{\centi\meter}.

The loaded cavity resonance frequency has been experimentally measured by looking at the reflected power while sweeping the microwave frequency.
\begin{figure}[t]
	\centering
	\includegraphics[width=0.7\columnwidth]{./Figure4.png}
	\caption{\label{fig:photo} Loaded cavity components prior to the assembly. In the picture it is also shown the first cylindrical thermal shield. As a dimensional reference, a 10 euro cent coin is shown.}
\end{figure}The loaded cavity absolute frequency at the operational temperature of \SI{65}{\degreeCelsius} is found to be \SI{120}{\mega\hertz} lower than the simulated value. This is compatible with a dielectric constant for the alumina material closer to $9.7$, rather than the nominal value ($\epsilon=9.4$) which is provided by the manufacturer at $\SI{8.5}{\giga\hertz}$~\cite{morgan-datasheet}. A fine tuning has been achieved by adjusting the cavity length by fractions of \SI{1}{\milli\meter}. A measurement of the cavity resonance frequency at different temperatures lead to an experimental temperature coefficient of \SI[per-mode=symbol]{-473}{\kilo\hertz\per\kelvin} for the untuned cavity and of \SI[per-mode=symbol]{-461}{\kilo\hertz\per\kelvin} for the tuned cavity, in good agreement with the simulations. No significant degradation of the cavity intrinsic quality factor has been observed in the range \SIrange{25}{70}{\degreeCelsius}, due to excess deposition of metallic Rb. Indeed, $Q_i$ has a value of 3600 at room temperature, decreasing to 3200 around \SI{70}{\degreeCelsius}.
\begin{figure}[]
	\includegraphics[width=\columnwidth]{./Figure5.pdf}
	\caption{\label{fig:resonance} $\mathrm{TE_{011}}$ resonance frequency as a function of microwave detuning at two limit temperatures (ambient temperature and \SI{75.5}{\degreeCelsius}). The plot shows the reflected power from the cavity, detected with a microwave circulator and photodiode.}
\end{figure}
In \Cref{fig:resonance} the loaded-cavity resonance mode is shown for two limit temperatures. The measurements shown refer to the cavity resonance previous to the fine tuning. From this measurement we can also determine the cavity coupling parameter $\beta$~\cite{Godone2004}, which has a value of 0.2.

The proposed cavity-cell assembly performance has been tested with a POP clock scheme. The cavity has been operated at ambient pressure, integrated into an existing structure (same as in \cite{Calosso2007}) composed of 2 layers of thermal shielding and 3 layers of magnetic shielding. A static quantization magnetic field lifts the Zeeman degeneracy and isolates the clock transition. The optics package is the one described in \cite{Micalizio2012}, including a distribuited feedback laser (DFB) working on the $D_2$ line, frequency stabilized with an external reference cell through saturated absorption spectroscopy. The laser frequency is tuned to the minimum of the clock cell absorption profile for the $\ket{F=2}$ atomic ground-state. The pulsing is provided by an amplitude-modulated acousto-optic modulator operating in single-pass configuration.  The system is completed with a low-noise digital control and acquisition system~\cite{Calosso2017} and the microwave synthesis chain presented in \cite{Francois2015}.
In \Cref{fig:Ramsey} a scan of the Ramsey fringes, obtained with a laser absorption measurement as the microwave frequency is swept, is shown. The total cycle time is \SI{3.35}{\milli\second}, including pumping, clock interrogation and detection. The free-evolution time  $T=\SI{2}{\milli\second}$, while the Rabi pulses are $\SI{0.4}{\milli\second}$ long. The laser beam is collimated with a gaussian waist $2 w = \SI{6}{\milli\meter}$. The pumping power is \SI{4}{\milli\watt}, for a pulse duration of \SI{0.4}{\milli\second}. The detection pulse power and duration are \SI{200}{\micro\watt} and \SI{0.15}{\milli\second} respectively. With such timings and parameters, we obtained a fringe contrast of about \SI{20}{\percent}.

To characterize the atomic properties of the Rb sample in the clock cell, we measured the longitudinal relaxation time $T_1$, directly accessible with an optical detection of the population evolution, with the Franzen method~\cite{Franzen1959,Gharavipour2017}. By this means we get $T_1 = \SI{1.7(2)}{\milli\second}$ at \SI{64.5}{\degreeCelsius}. The transverse relaxation time $T_2$ is inferred by comparing envelope of the experimental Ramsey fringes to the one computed with the theory developed in \cite{Micalizio2013}. From this analysis, it turns out that $T_2$ is roughly $\SI{10}{\percent}$ lower than $T_1$, corresponding to $\gamma_2\simeq\SI{650}{\per\second}$.\\
\begin{figure}[]
	\includegraphics[width=\columnwidth]{./Figure6.pdf}
	\caption{\label{fig:Ramsey} Ramsey scan of the atomic line (absorption signal as a function of the microwave detuning from the atomic frequency; each data point is the result of 3 averages). Cavity temperature \SI{64.5}{\degreeCelsius}, free-evolution time $T = \SI{2.0}{\milli\second}$, Rabi pulses length $t_1 = \SI{0.4}{\milli\second}$.}
\end{figure}
The shift induced on the clock transition by the buffer gas is \SI[retain-explicit-plus]{+8555(5)}{\hertz}, consistent with a total buffer gas pressure of \SI{49(2)}{\torr}, assuming negligible error on the buffer gas composition~\cite{Vanier1982}.

A finer tuning of the clock operating parameters (optical power, beam waist, cycle time, etc...) is needed, seeking for the ultimate stability performances.  However,  a stability below $\num{5e-13}$ at \SI{1}{\second} is compatible with the clock signal shown in \Cref{fig:Ramsey}, considering the major noise sources of the current setup (including laser RIN and frequency noise, detector noise, etc...). This estimate is confirmed by preliminary measurements and will be further characterized in future works.

\section{Conclusions}
\label{sec:conclusions}
A compact cavity-cell assembly, based on high-grade purity alumina as loading material has been designed, realized and characterized in terms of the main parameters of interest for microwave clock applications. The dielectric loading has lead to a reduction of a factor 10 of the inner cavity volume, compared to the traditional cylindrical cavity. The size reduction was achieved by maintaining the favorable field uniformity of the $\mathrm{TE_{011}}$ mode and high cavity quality factor.

Despite the scaling of the clock cell dimension, introduced to push the miniaturization, we achieved high fringe contrast and high atomic-line quality factor by integrating the cavity in a POP clock setup. The obtained clock signal is compatible with a high-performing vapor-cell Rb clock, with short-term in the mid $10^{-13}\,\tau^{-1/2}$, as shown by preliminary characterization. The reduced size of the assembly facilitates thermal uniformity, with foreseen benefits in the medium-long term stability.

The loaded-cavity approach thus adds to the existing design options for the realization of compact vapor cell clocks based on microwave interrogation. As shown in \cite{Wang2008}, more refined configurations can also be studied to make the design even more robust against environmental sensitivities. In this paper we reported a quality factor rather high for the POP with optical detection. If needed, this value can be tailored by using alumina with different percentages of impurities.

The proposed loaded-cavity assembly paves the way for a strongly miniaturized Rb clock physics package with low mass and power consumption, particularly appealing for spaceborne applications.

\section*{Acknowledgments}
The authors thank Elio K. Bertacco for precious technical help and Marwan S.p.A. (Pisa, Italy) for the cell filling. We acknowledge valuable input on the alumina production process from J\"{o}rg-Uwe Wichert from Wesgo Ceramics (Erlangen, Germany) and Wesgo Ceramics GmbH for the alumina pieces procurement. We also thank the LED laboratory staff from Politecnico di Torino for providing the CST software and computational facility.

\bibliographystyle{ieeetr}

redpajama_set_name: RedPajamaArXiv


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During Thanksgiving I got to spend some time with my family in California and was reminded again of just how brilliant the Johns girls are. (Candis Christina & Cami) The Johns boys (George Reg & Curtis) on the other hand, now what was it all our teachers said about us, ahh yeah now I remember "they didn't apply themselves". The reason I bring this all up is because we finally have a Johns boy who may smoke the Johns girls. Presently I'm proud to say my Daughter Cami is finishing up her Senior year at Wellington High in the honors program.
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Not in my top 5, not to worry!
hey george…merry christmas to you and all of yours….sherry and our two kids and myself are now u.s citizens…feels good.


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Plenty has been made of the Reds inability to win their last two fixtures against Leicester and West Ham, while their main rivals Man City have made the most of that mini blip and climbed back to the top of the table albeit having played a game more.
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However, he has been around long enough to know he can't change what people think.
"For us, I did not see what they all say they can see in our faces.
"When I talked to the referee after the game (at West Ham) they said now he is nervous.' I did not think it but I cannot change it.
"There was never a guarantee this season. People always wanted the biggest gap in the world, pretty much, 25 points, whatever, and then only three games to go. That's nice, but it's not the reality."
The two clashes against the Foxes and Hammers have seen Liverpool lack any kind of fluency in a attacking sense, while the defence which had previously been the strength this season, has started to look a bit vulnerable under pressure.
Klopp knows they have to improve their game once again if they want to realise their title dream this season but maintains there were mitigating reasons behind the sluggish displays.
"We are very critical. In the outside world, we can never use any real explanations because it's then always used as being an excuse.
"But internally, we have to talk about why it was a bit more difficult. It's not cool if we cannot train with the team we want to play.
"We still should have performed better, especially in the Leicester game. The pitch didn't help. Nobody has to write that any more. It's just a fact. It made the game really difficult.
"West Ham was always a tough place to go and a few other teams realised that already.
"Getting a point there, and having more chances, stuff like that, which nobody even thinks after the game, it's like you have to dominate them constantly and they are not allowed to have anything.
There is a view that injuries to members of the back four have contributed the team conceding five goals in the past three games, but the manager was not using that as a excuse.
"It is never cool if you have to change but the goals we conceded were not because of the changes to the last line.
"If you look at the goals and make the analysis, the goal against West Ham and Leicester had nothing to do with the last line. That is the 100% truth.
"The goals against Palace, maybe, we had to change a lot in the game and had a red card. It is always better if you can keep seven or eight players always playing and change three or four and keep it like this."
As Klopp says, when expectations are raised, more questions follow when things don't go to plan.
The best way to answer that is to claim the three points in the fixtures ahead.
And that is what the Reds aim to do.