bluuebunny/crossref_metadata_2025_split huggingface dataset:
ALMA and IRIS Observations of the Solar Chromosphere. II. Structure and Dynamics of Chromospheric Plages
Authors: Chintzoglou Georgios , De Pontieu Bart , Martínez-Sykora Juan , Hansteen Viggo , Cruz Rodríguez Jaime de la , Szydlarski Mikolaj , Jafarzadeh Shahin , Wedemeyer Sven , Bastian Timothy S. , Dalda Alberto Sainz 
Published: January 2021

Abstract
We propose and employ a novel empirical method for determining chromospheric plage regions, which seems to better isolate a plage from its surrounding regions than other methods commonly used. We caution that isolating a plage from its immediate surroundings must be done with care in order to successfully mitigate statistical biases that, for instance, can impact quantitative comparisons between different chromospheric observables. Using this methodology, our analysis suggests that λ = 1.25 mm free–free emission in plage regions observed with the Atacama Large Millimeter/submillimeter Array (ALMA)/Band6 may not form in the low chromosphere as previously thought, but rather in the upper chromospheric parts of dynamic plage features (such as spicules and other bright structures), i.e., near geometric heights of transition-region temperatures. We investigate the high degree of similarity between chromospheric plage features observed in ALMA/Band6 (at 1.25 mm wavelengths) and the Interface Region Imaging Spectrograph (IRIS)/Si iv at 1393 Å. We also show that IRIS/Mg ii h and k are not as well correlated with ALMA/Band6 as was previously thought, and we discuss discrepancies with previous works. Lastly, we report indications of chromospheric heating due to propagating shocks supported by the ALMA/Band6 observations.
Confrontation of Observation and Theory: High-frequency QPOs in X-Ray Binaries, Tidal Disruption Events, and Active Galactic Nuclei
Authors: Smith Krista Lynne , Tandon Celia R. , Wagoner Robert V. 
Published: January 2021

Abstract
We compile observations of high-frequency quasi-periodic oscillations (QPOs) around black holes, both stellar and supermassive, and compare their positions in the parameter space of black hole mass, spin, and oscillation frequency. We find that supermassive black holes occupy a separate region of parameter space than stellar, and further, that QPOs seen around tidal disruption events rather than Seyfert-type active galactic nuclei (AGN) occupy an entirely different space. We then compare these results to the orbital resonance, diskoseismic, warped disk, and disk–jet coupling theoretical models for the origin of high-frequency QPOs. We find that while oscillations around stellar mass black holes are generally consistent with the above models, supermassive black holes are decidedly not. Oscillations seen in tidal disruption events are consistent with oscillations near the frequency of the innermost stable circular orbit, while QPOs in AGN are not accounted for by any of the physical models in consideration. This indicates that despite the scale invariance of accretion processes implied by a decades-wide correlation between QPO frequency and black hole mass, any theory of high-frequency QPOs must relate the frequency to more than just the mass and spin.
A Two-zone Photohadronic Interpretation of the EHBL-like Behavior of the 2016 Multi-TeV Flares of 1ES 1959+650
Authors: Sahu Sarira , López Fortín Carlos E. , Castañeda Hernández Luis H. , Rajpoot Subhash 
Published: January 2021

Abstract
The high-energy-peaked blazar 1ES 1959+650 is a well-known and well-studied nearby blazar that has undergone several episodes of multi-TeV flaring. In 2002 for the first time an orphan TeV flare was observed from this blazar. During a multiwavelength campaign from 2016 April 29 to November 21, MAGIC telescopes observed multi-TeV flarings during the nights of 2016 June 13 and 14 and July 1 when the position of the synchrotron peak was found to be above 1017 Hz. Also observed was that the second peak of the spectral energy distribution shifted toward higher energy and exhibited extreme HBL-like behavior. The photohadronic model, which is very successful at explaining the multi-TeV flaring from many high energy blazars, including 1ES 1959+650, is applied to study the flaring events of 2016. It is observed that the photohadronic model is unable to explain the observed spectra. Here, we use a two-zone photohadronic model to explain the observed spectra. We clearly demonstrate that the low energy regime (zone-1) of the spectra corresponds to the standard flaring events of the high energy blazar and the high energy regime (zone-2) of the spectra is solely due to the extreme nature of the flaring events. Our two-zone photohadronic model explains the multi-TeV flaring events observed by MAGIC telescopes very well.
Correlated X-Ray and Optical Variability in the O-type Supergiant ζ Puppis
Authors: Nichols Joy S. , Nazé Yaël , Huenemoerder David P. , Moffat Anthony F. J. , Miller Nathan A. , Lauer Jennifer , Ignace Richard , Gayley Ken , Ramiaramanantsoa Tahina , Oskinova Lidia , Hamann Wolf-Rainer , Richardson Noel D. , Waldron Wayne L. , Dahmer Matthew 
Published: January 2021

Abstract
Analysis of the recent long exposure Chandra X-ray observation of the early-type O star ζ Pup shows clear variability with a period previously reported in optical photometric studies. These 813 ks of HETGS observations taken over a roughly one-year time span have two signals of periodic variability: (1) a high-significance period of 1.7820 ± 0.0008 day, and (2) a marginal detection of periodic behavior close to either 5 days or 6 days. A BRITE-Constellation nanosatellite optical photometric monitoring (using near-contemporaneous observations to the Chandra data) confirms a 1.78060 ± 0.00088 day period for this star. The optical period coincides with the new Chandra period within their error ranges, demonstrating a link between these two wave bands and providing a powerful lever for probing the photosphere-wind connection in this star. The phase lag of the X-ray maximum relative to the optical maximum is ∼ ϕ = 0.45, but consideration of secondary maxima in both data sets indicates possibly two “hot” spots on the star with an X-ray phase lag of ϕ = 0.1 each. The details of this periodic variation of the X-rays are probed by displaying a phased and trailed X-ray spectrum and by constructing phased light curves for wavelength bands within the HETGS spectral coverage (ranging down to bands encompassing groups of emission lines). We propose that the 1.78 day period is the stellar rotation period and explore how stellar bright spots and associated corotating interaction regions (CIRs) could explain the modulation of this star’s optical and X-ray output and their phase difference.
Fundamental Reference AGN Monitoring Experiment (FRAMEx). I. Jumping Out of the Plane with the VLBA
Authors: Fischer Travis C. , Secrest Nathan J. , Johnson Megan C. , Dorland Bryan N. , Cigan Phillip J. , Fernandez Luis C. , Hunt Lucas R. , Koss Michael , Schmitt Henrique R. , Zacharias Norbert 
Published: January 2021

Abstract
We present the first results from the Fundamental Reference active galactic nucleus (AGN) Monitoring Experiment, an observational campaign dedicated to understanding the physical processes that affect the apparent positions and morphologies of AGNs. In this work, we obtained simultaneous Swift X-ray Telescope and Very Long Baseline Array (VLBA) radio observations for a snapshot campaign of 25 local AGNs that form a volume-complete sample with hard X-ray (14–195 keV) luminosities above 1042 erg s−1, out to a distance of 40 Mpc. Despite achieving an observation depth of ∼20 μJy, we find that 16 of 25 AGNs in our sample are not detected with the VLBA on milliarcsecond (subparsec) scales, and the corresponding core radio luminosity upper limits are systematically below predictions from the Fundamental Plane of black hole activity. Using archival Jansky Very Large Array (VLA) radio measurements, our sample jumps back onto the Fundamental Plane, suggesting that extended radio emission is responsible for the apparent correlation between radio emission, X-ray emission, and black hole mass. We suggest that this discrepancy is likely due to extranuclear radio emission produced via interactions between the AGN and host environment. We compare VLBA observations of AGNs to VLA observations of nearby Galactic black holes, and we find a mass-independent correlation between radio and X-ray luminosities of black holes of

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∼10−6, in line with predictions for coronal emission, but allowing for the possibility of truly radio-silent AGNs.
Solar Bayesian Analysis Toolkit—A New Markov Chain Monte Carlo IDL Code for Bayesian Parameter Inference
Authors: Anfinogentov Sergey A. , Nakariakov Valery M. , Pascoe David J. , Goddard Christopher R. 
Published: January 2021

Abstract
We present the Solar Bayesian Analysis Toolkit (SoBAT), which is a new easy to use tool for Bayesian analysis of observational data, including parameter inference and model comparison. SoBAT is aimed (but not limited) to be used for the analysis of solar observational data. We describe a new IDL code designed to facilitate the comparison of a user-supplied model with data. Bayesian inference allows prior information to be taken into account. The use of Markov Chain Monte Carlo sampling allows efficient exploration of large parameter spaces and provides reliable estimation of model parameters and their uncertainties. The Bayesian evidence for different models can be used for quantitative comparison. The code is tested to demonstrate its ability to accurately recover a variety of parameter probability distributions. Its application to practical problems is demonstrated using studies of the structure and oscillation of coronal loops.
Bursts before Burst: A Comparative Study on FRB 200428-associated and FRB-absent X-Ray Bursts from SGR J1935+2154
Authors: Yang Yu-Han , Zhang Bin-Bin , Lin Lin , Zhang Bing , Zhang Guo-Qiang , Yang Yi-Si , Tu Zuo-Lin , Zou Jin-Hang , Ye Hao-Yang , Wang Fa-Yin , Dai Zi-Gao 
Published: January 2021

Abstract
Accompanied by an X-ray burst, the fast radio burst (FRB) FRB 200428 was recently confirmed as originating from the Galactic magnetar soft gamma repeater (SGR) SGR J1935+2154. Just before and after FRB 200428 was detected, the Five-hundred-meter Aperture Spherical radio Telescope (FAST) had been monitoring SGR J1935+2154 for eight hours. From UTC 2020 April 27 23:55:00 to 2020 April 28 00:50:37, FAST detected no pulsed radio emission from SGR J1935+2154, while Fermi/Gamma-ray Burst Monitor registered 34 bursts in the X/soft γ-ray band, forming a unique sample of X-ray bursts in the absence of FRBs. After a comprehensive analysis on light curves, time-integrated, and time-resolved spectral properties of these FRB-absent X-ray bursts, we compare this sample with the FRB-associated X-ray burst detected by Insight-HXMT, INTEGRAL, and Konus-Wind. The FRB-associated burst distinguishes itself from other X-ray bursts by its nonthermal spectrum and a higher spectral peak energy, but otherwise is not atypical. We also compare the cumulative energy distribution of our X-ray burst sample with that of first repeating FRB source, FRB 121102, with the calibration of FRB 200428-X-ray burst association. We find a similarity between the two, offering indirect support of the magnetar origin of cosmological FRBs. The event rate density of magnetar bursts is about ∼150 times higher than the FRB event rate density at the energy of FRB 200428. This again suggests that, if all FRBs originate from magnetars, only a small fraction of X-ray bursts are associated with FRBs.
Nonlinear Alfvén Wave Model of Stellar Coronae and Winds from the Sun to M Dwarfs
Authors: Sakaue Takahito , Shibata Kazunari 
Published: January 2021

Abstract
An M dwarf’s atmosphere and wind are expected to be highly magnetized. The nonlinear propagation of Alfvén waves could play a key role in both heating the stellar atmosphere and driving the stellar wind. Using this Alfvén wave scenario, we carried out a one-dimensional compressive magnetohydrodynamic simulation to examine the nonlinear propagation of Alfvén waves from the M dwarf’s photosphere, chromosphere to the corona, and interplanetary space. Based on the simulation results, we developed a semi-empirical method describing the solar and M dwarf’s coronal temperature, stellar wind velocity, and wind’s mass-loss rate. We find that M dwarfs’ coronae tend to be cooler than the solar corona, and that M dwarfs’ stellar winds can be characterized as having a faster velocity and much smaller mass-loss rate compared to those of the solar wind.
A Novel Analytic Atmospheric T(τ) Relation for Stellar Models
Authors: Ball Warrick H. 
Published: January 2021

Abstract
Stellar models often use relations between the temperature T and optical depth τ to evaluate the structure of their optically thin outer layers. We fit a novel analytic function to the Hopf function q(τ) of a radiation-coupled hydrodynamics simulation of near-surface convection with solar parameters by Trampedach et al. The fit is accurate to within 0.82% for the solar simulation and to within 13% for all the simulations that are not on either the low-temperature or low-gravity edges of the grid of simulations.
Le scandale financier comme projet de recherche
Authors: Mazbouri Malik , Giddey Thibaud , Baubeau Patrice 
Published: January 2021

Comme tout autre type de scandale, le scandale financier est un objet hybride, qui pose à la recherche des problèmes de repérage et de définition. Son histoire n’est pas à confondre avec celle de la corruption ou des transgressions, ni avec celle des crises et des krachs. Injustement boudé, à de rares exceptions près, par la profession historienne, le scandale financier permet pourtant d’interroger le régime des valeurs et des normes légales ou morales qui gouvernent une société ainsi que les formes de mobilisations et de contre-mobilisations auxquelles donnent (ou non) lieu la mise en cause publique d’acteurs issus du monde de l’économie et de la finance. Exposant au regard collusions inavouables et collisions inattendues, il est toutefois plus qu’un simple révélateur des relations entre l’argent et le pouvoir : sa dynamique même se nourrit des transformations qu’il est capable ou incapable d’impulser dans le fonctionnement usuel des différents univers sociaux qu’il met en tension. C’est à cet objet riche et pluridimensionnel, enjeu d’investissements stratégiques et sémantiques toujours intéressés, que sont consacrées les contributions réunies dans le présent numéro d’ Entreprises et Histoire . Celui-ci veut être à la fois un hommage aux travaux pionniers parus sur la question et un appel à renouveler les recherches sur cette thématique qui intéresse aussi bien l’histoire économique et financière que l’histoire sociale, politique et culturelle.
Au prisme du scandale : crise, faillites bancaires et régulation financière dans la France de l’entre-deux-guerres
Authors: Baubeau Patrice , Riva Angelo 
Published: January 2021

Dans cet article, nous montrons que les scandales financiers sont un facteur explicatif clé du « retard » français dans l’adoption d’une réglementation bancaire. Les scandales financiers, dont la presse s’est emparée, ont attiré l’attention de l’opinion et des pouvoirs publics sur la protection de l’épargne investie en titres, plutôt que sur celle déposée sur des comptes bancaires. Or ces scandales ont provoqué des faillites retentissantes pour les intermédiaires financiers engagés dans l’émission et le placement de titres, plutôt que dans des activités de collecte de dépôts et d’octroi de crédits réalisées par les banques à réseaux. La forte diminution des dépôts et des crédits au sein de ces dernières n’a en revanche pas soulevé de grands débats : d’une part, l’absence de statistiques publiques consolidées a caché l’ampleur du phénomène ; d’autre part, cette diminution des dépôts n’a pas résulté des pertes des déposants, mais d’une fuite des dépôts vers la sécurité représentée par les caisses d’épargne. Ainsi, lors des débats sur les faillites et difficultés financières, les enjeux principaux furent les pertes subies par les épargnants acquéreurs de titres de placement et les lacunes dans la réglementation des sociétés par actions. Même en cas de faillite d’une banque à réseaux, les débats portèrent sur le comportement imprudent d’administrateurs aventureux, au détriment et à l’insu de leurs actionnaires et déposants. Des lois de 1930 aux décrets de 1935, le Parlement et les gouvernements ont ainsi tâché, plutôt que de réguler l’activité bancaire, de protéger l’épargne et de réformer les sociétés par actions, afin de rétablir la confiance, de restaurer la prospérité et de défendre le Franc.
Le Crédit lyonnais, un quart de siècle de scandale financier en France (1994-2020)
Authors: de Blic Damien 
Published: January 2021

Le scandale du Crédit lyonnais qui nourrit régulièrement l’actualité politique et financière française depuis son éclatement en 1994 se présente comme une énigme. D’un côté, il est dénoncé comme un scandale majeur sans équivalent dans l’histoire financière ; de l’autre, il ne suscite que de faibles mobilisations et ses dénonciateurs peinent à en identifier les responsabilités. L’article propose de comprendre ce paradoxe en abordant l’événement du point de vue de la sociologie pragmatique attentive aux normes et aux motifs d’indignation partagés au sein d’un groupe social ou national et sur lesquels s’appuient les dénonciations publiques. Cette perspective permet d’éclairer le scandale en l’inscrivant dans une séquence longue où il intervient entre une période initiale (jusqu’au milieu des années 1980), où une dénonciation de « l’argent » garantit généralement en France une écoute favorable dans différents secteurs de la société, et une période postérieure (à partir du début des années 2000), où les banques et le secteur financier se retrouvent au cœur de la critique sociale. Entre les deux, au moment où intervient le scandale Crédit lyonnais, la critique de la banque et de la finance n’offre que des ressources politiques limitées dans une conjoncture politique spécifique. Alors même que les événements et le contexte de dérégulation dans lesquels sont nées les actions à l’origine du scandale du Crédit lyonnais présentent une forte ressemblance tant avec ceux précédant la crise de 2008 (contournement des règles prudentielles, tentative incontrôlée de constitution d’une banque universelle, dimension transnationale) que dans les tentatives de solution à la crise (argument du « Too Big To Fail », recapitalisations par l’État, séparation d’une banque saine d’une « bad bank »), les dénonciations formulées dans les années 1990 s’en tiennent à un appel aux vertus du marché contre l’interventionnisme étatique. Ce paysage normatif se trouve bouleversé au début des années 2000 sous l’effet des mobilisations transnationales ciblant les méfaits d’un capitalisme désormais désigné comme « financier », et s’en prenant plus généralement aux effets sociaux de la financiarisation, tout particulièrement après la crise des subprimes.
Enhancement of ESD performances of Silicon Capacitors for RFID solutions
Authors: Jacqueline Sébastien , Bunel Catherine , Lengignon Laurent 
Published: January 2021

Abstract
Radio-Frequency IDentification devices such as smart cards and RFID tags are based on the presence of a resonant tuned LC circuit associated to the RFID Integrated Circuit (IC). The use of discrete capacitor, external to the IC gives greater flexibility and design freedom. In the race of miniaturization, manufacturers of RFID devices always require smaller electronic components. To save space and in the same time improve performances, capacitors are exposed to height and volume constraints. In the same time, the capacitor has to withstand ESD stresses that can occur during the assembly of the device and during operation.
Murata has developed a unique thin capacitor technology in silicon. This paper reports the development of a range of low profile capacitors with enhanced ESD performances. The manufacturing process optimization and the design adjustments will be presented here.
The process was optimized by taking into account the main electrical parameters: leakage current, breakdown voltage, capacitance density, capacitance accuracy, Equivalent Series Resistance (ESR) and Self-Resonant Frequency (SRF). The dielectric stack was defined in order to integrate up to 330pF in 0402 case. The process architecture, based on accurate planar capacitor with thick dielectric will be discussed. With this architecture there is no constraint to reach low thickness, such as 100μm or even lower.
The ESD threshold of each Silicon Capacitor was investigated with design variations associated to Human Body Model measurements. A Single Project Wafer (SPW) was founded with 36 different capacitor designs. Design modulations specifically addressed the orientation and position of the contacts openings. Special care was taken to maximize the width of the contact holes and metal tracks. A mosaic approach, constructed out of a massive network of parallelized elementary cells was also implemented, so that the charges of the ESD pulse do not concentrate at the same place, leading to electrical failure. Examples of defects due to ESD stress will be shown with failure analysis cross-sections and ways to enhance the ESD threshold by design will be illustrated.
Wireless Sensor Platform for Nanosensor Interface Electronics
Authors: Kim Bruce , Gupta Anurag , Spryn Mitchell 
Published: January 2021

Abstract
In this paper, we describe a low-cost modular sensing system that can be used to interface with nanosensors. We used nanosensors to detect CO2 gas. In addition, the system can be easily modified to incorporate multiple analog and digital sensors, decreasing the amount of effort needed to integrate multiple sensors.
Acceleration Factors and Life Predictions
Authors: Chris South P.E. 
Published: January 2021

Abstract
Acceleration factors (AF) are key to designing an effective accelerated life test (ALT). They represent the ratio of the time in field to the time in test for a particular event to occur (typically a failure event related to a specific failure mechanism). Time to failure for a device generally correlates with the amount of stress applied (the higher the stress, the quicker the device will fail), and failure models exist to mathematically define that correlation for various failure mechanisms. This allows for use of a higher stress in test than in the field, thereby providing an acceleration factor that shortens the time in test to demonstrate a failure-free time period.
ALT can take the form of qualitative or quantitative testing. The latter is used to determine the life characteristics of the device with some reliability and confidence level. Usage rate acceleration and higher stress acceleration can be used. It is important to consider the design limits of the device based on its specification and material properties, and limit the stress levels in test so as not to induce failure mechanisms that the device would not otherwise have experienced in the field.
ALT results are used to make life predictions for the device tested. With no failures, the test results demonstrate the required reliability and confidence level metrics for the failure mechanism of interest. With several failures, a reliability software tool can be used with the appropriate analysis method, rank method, and confidence bounds method chosen in order to extrapolate to an expected life in test. The equivalent field life is based on multiplying the expected life in test by the AF. If the field stress and/or test stress are not constant, there are multiple acceleration factors to utilize. As a result, an equivalent acceleration factor needs to be calculated and used as the AF when predicting equivalent field life.