bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extragalactic Magnetism with SOFIA (SALSA Legacy Program). VII. A Tomographic View of Far-infrared and Radio Polarimetric Observations through MHD Simulations of Galaxies
Authors: Martin-Alvarez Sergio , Lopez-Rodriguez Enrique , Dacunha Tara , Clark Susan E. , Borlaff Alejandro S. , Beck Rainer , Rodríguez Montero Francisco , Jung Seoyoung L. , Devriendt Julien , Slyz Adrianne , Roman-Duval Julia Christine , Ntormousi Evangelia , Tahani Mehrnoosh , Subramanian Kandaswamy , Dale Daniel A. , Marcum Pamela M. , Tassis Konstantinos , del Moral-Castro Ignacio , Tram Le Ngoc , Jarvis Matt J. 
Published: April 2024

Abstract
The structure of magnetic fields in galaxies remains poorly constrained, despite the importance of magnetism in the evolution of galaxies. Radio synchrotron and far-infrared (FIR) polarization and polarimetric observations are the best methods to measure galactic scale properties of magnetic fields in galaxies beyond the Milky Way. We use synthetic polarimetric observations of a simulated galaxy to identify and quantify the regions, scales, and interstellar medium (ISM) phases probed at FIR and radio wavelengths. Our studied suite of magnetohydrodynamical cosmological zoom-in simulations features high-resolutions (10 pc full-cell size) and multiple magnetization models. Our synthetic observations have a striking resemblance to those of observed galaxies. We find that the total and polarized radio emission extends to approximately double the altitude above the galactic disk (half-intensity disk thickness of h
I radio ∼ h
PI radio = 0.23 ± 0.03 kpc) relative to the total FIR and polarized emission that are concentrated in the disk midplane (h
I FIR ∼ h
PI FIR = 0.11 ± 0.01 kpc). Radio emission traces magnetic fields at scales of ≳300 pc, whereas FIR emission probes magnetic fields at the smallest scales of our simulations. These scales are comparable to our spatial resolution and well below the spatial resolution (<300 pc) of existing FIR polarimetric measurements. Finally, we confirm that synchrotron emission traces a combination of the warm neutral and cold neutral gas phases, whereas FIR emission follows the densest gas in the cold neutral phase in the simulation. These results are independent of the ISM magnetic field strength. The complementarity we measure between radio and FIR wavelengths motivates future multiwavelength polarimetric observations to advance our knowledge of extragalactic magnetism.
The Gasing Pangkah Collaboration. I. Asteroseismic Identification and Characterization of a Rapidly Rotating Engulfment Candidate*
Authors: Ong 王 J. M. Joel 加冕 , Hon Marc Teng Yen , Soares-Furtado Melinda , Stephan Alexander P. , van Saders Jennifer , Tayar Jamie , Shappee Benjamin , Hey Daniel R. , Cao Lyra , Yıldız Mutlu , Orhan Zeynep Çelik , Örtel Sibel , Montet Benjamin , Holoien Thomas W.-S. , Bland-Hawthorn Joss , Buder Sven , De Silva Gayandhi M. , Freeman Ken C. , Martell Sarah L. , Lewis Geraint F. , Sharma Sanjib , Stello Dennis 
Published: April 2024

Abstract
We report the discovery and characterization of TIC 350842552 (“Zvrk”), an apparently isolated, rapidly rotating (P
rot ∼ 99 days) red giant observed by TESS in its southern Continuous Viewing Zone. The star’s fast surface rotation is independently verified by the use of p-mode asteroseismology, strong periodicity in TESS and ASAS-SN photometry, and measurements of spectroscopic rotational broadening. A two-component fit to APOGEE spectra indicates a coverage fraction of its surface features consistent with the amplitude of the photometric rotational signal. Variations in the amplitude of its photometric modulations over time suggest the evolution of its surface morphology and therefore enhanced magnetic activity. We further develop and deploy new asteroseismic techniques to characterize radial differential rotation, but find at best only weak evidence for rotational shear within Zvrk’s convective envelope. This high surface rotation rate is incompatible with models of angular-momentum transport in single-star evolution. Spectroscopic abundance estimates also indicate a high lithium abundance, among other chemical anomalies. Taken together, all of these suggest a planet-ingestion scenario for the formation of this rotational configuration, various models for which we examine in detail.
Unveiling the Initiation Route of Coronal Mass Ejections through Their Slow Rise Phase
Authors: Xing Chen , Aulanier Guillaume , Cheng Xin , Xia Chun , Ding Mingde 
Published: April 2024

Abstract
Understanding the early evolution of coronal mass ejections (CMEs), in particular their initiation, is the key to forecasting solar eruptions and induced disastrous space weather. Although many initiation mechanisms have been proposed, a full understanding of CME initiation, which is identified as a slow rise of CME progenitors in kinematics before impulsive acceleration, remains elusive. Here, with a state-of-the-art thermal magnetohydrodynamics simulation, we determine a complete CME initiation route in which multiple mainstream mechanisms occur in sequence yet are tightly coupled. The slow rise is first triggered and driven by the developing hyperbolic flux tube (HFT) reconnection. Subsequently, the slow rise continues as driven by the coupling of the HFT reconnection and the early development of torus instability. The end of the slow rise, i.e., the onset of the impulsive acceleration, is induced by the start of the fast magnetic reconnection coupled with the torus instability. These results unveil that CME initiation is a complicated process involving multiple physical mechanisms, thus being hardly resolved by a single initiation mechanism.
Mass Assembly in Massive Star Formation: A Fragmentation Study of ATLASGAL Clumps
Authors: Pandian Jagadheep D. , Chatterjee Rwitika , Csengeri Timea , Williams Jonathan P. , Wyrowski Friedrich , Menten Karl M. 
Published: April 2024

Abstract
The mass assembly in star-forming regions arises from the hierarchical structure in molecular clouds in tandem with fragmentation at different scales. In this paper, we present a study of the fragmentation of massive clumps covering a range of evolutionary states, selected from the ATLASGAL survey, using the compact configuration of the Submillimeter Array. The observations reveal a wide diversity in the fragmentation properties with about 60% of the sources showing limited to no fragmentation at the 2″ scale, or a physical scale of 0.015–0.09 pc. We also find several examples where the cores detected with the Submillimeter Array are significantly offset from the clump potential, suggesting that initial fragmentation does not result in the formation of a large number of Jeans mass fragments. The fraction of the clump mass that is in compact structures is seen to increase with source evolution. We also see a significant correlation between the maximum mass of a fragment and the bolometric luminosity of the parent clump. These suggest that massive star formation proceeds through clump fed core accretion, with the initial fragmentation being dependent on the density structure of the clumps and/or magnetic fields.
Nonlinear Wave Damping by Kelvin–Helmholtz Instability-induced Turbulence
Authors: Hillier Andrew , Arregui Iñigo , Matsumoto Takeshi 
Published: April 2024

Abstract
Magnetohydrodynamic kink waves naturally form as a consequence of perturbations to a structured medium, for example, transverse oscillations of coronal loops. Linear theory has provided many insights into the evolution of linear oscillations, and results from these models are often applied to infer information about the solar corona from observed wave periods and damping times. However, simulations show that nonlinear kink waves can host the Kelvin–Helmholtz instability (KHI), which subsequently creates turbulence in the loop, dynamics that are beyond linear models. In this paper we investigate the evolution of KHI-induced turbulence on the surface of a flux tube where a nonlinear fundamental kink mode has been excited. We control our numerical experiment so that we induce the KHI without exciting resonant absorption. We find two stages in the KHI turbulence dynamics. In the first stage, we show that the classic model of a KHI turbulent layer growing at ∝t is applicable. We adapt this model to make accurate predictions of the damping of the oscillation and turbulent heating as a consequence of the KHI dynamics. In the second stage, the now dominant turbulent motions are undergoing decay. We find that the classic model of energy decay proportional to t
−2 approximately holds and provides an accurate prediction of the heating in this phase. Our results show that we can develop simple models for the turbulent evolution of a nonlinear kink wave, but the damping profiles produced are distinct from those of linear theory that are commonly used to confront theory and observations.
Unusually Low-frequency Whistler-mode Waves and Their Association with High-energy Protons Observed Upstream of Martian Bow Shock
Authors: Jin Taifeng , Ni Binbin , Fu Song , Li Lei , Cao Xing , Pang Shuyue , Yun Xiaotong , Long Minyi , Du Hengle 
Published: April 2024

Abstract
Whistler-mode waves upstream of planetary bow shock are often referred to as “1-Hz waves” due to the center of their observed frequency range being at ∼1 Hz. A series of whistler-mode waves were observed upstream of the Martian bow shock by MAVEN on 2015 August 14, with unusually low frequencies centered at ∼0.4 Hz. These waves were accompanied (though not synchronized) by the significant flux enhancement of high-energy protons up to ∼10 keV. By analyzing the wave dispersion property and the wave–particle interaction condition, we find that the observed whistler-mode waves have the potential of resonating with protons of ∼1 keV with large pitch angles up to nearly perpendicular to the background magnetic field, thereby providing a feasible means of accounting for proton acceleration. Our results indicate the possible origin of energized protons in the Martian environment through the interaction with whistler-mode waves, and their potential relationship with the unique upstream conditions.
A Consistent Explanation for the Unusual Initial Mass Function and Star Formation Rate in the Central Molecular Zone (CMZ)
Authors: Chabrier Gilles , Dumond Pierre 
Published: April 2024

Abstract
We examine various physical processes that may explain the shallow high-mass slope of the initial mass function (IMF), as well as the low star formation rate (SFR) in star-forming molecular clouds (MCs) in the Central Molecular Zone (CMZ). We show that the strong tidal field and shear experienced by the CMZ have opposite effects on the collapse of density fluctuations and cannot explain these properties. Similarly, we show that the intense magnetic field in the CMZ provides a negligible pressure support and, for the high densities at play, should not modify the probability density function of the turbulent gas flow, thus affecting negligibly the IMF. However, we show that, in contrast to the MCs in the Galactic disk, the ones in the CMZ experience only one single episode of turbulence cascade. Indeed, their rather short lifetime, due to their high mean densities, is similar to one typical turbulence crossing time. Consequently, according to the Hennebelle–Chabrier theory of star formation, within this “single turbulence cascade episode,” the cloud experiences one single field of turbulence-induced density fluctuations, leading eventually to gravitationally unstable cores. As shown in Hennebelle & Chabrier (2013), this yields a shallower IMF than usual and leads to the correct observed slope for the CMZ star-forming clouds. Similarly, this single large-scale turbulence event within the cloud lifetime yields a 5–6 times lower SFR than under usual conditions, in agreement with the observed values. Therefore, we suggest that this “single turbulence cascade” scenario can explain both the shallow IMF and low SFR of clouds in the CMZ.
Virial Black Hole Masses for Active Galactic Nuclei behind the Magellanic Clouds
Authors: Panda Swayamtrupta , Kozłowski Szymon , Gromadzki Mariusz , Wrona Marcin , Iwanek Patryk , Udalski Andrzej , Szymański Michał K. , Soszyński Igor , Pietrukowicz Paweł , Ulaczyk Krzysztof , Skowron Jan , Poleski Radosław , Mróz Przemek , Skowron Dorota M. , Rybicki Krzysztof , Mróz Mateusz 
Published: April 2024

Abstract
We use the spectroscopic data collected by the Magellanic Quasars Survey (MQS) and the photometric V- and I-band data from the Optical Gravitational Lensing Experiment (OGLE) to measure the physical parameters for active galactic nuclei (AGNs) located behind the Magellanic Clouds. The flux-uncalibrated MQS spectra were obtained with the 4 m Anglo-Australian Telescope and the AAOmega spectroscope (R = 1300) in a typical ∼1.5 hr visit. They span a spectral range of 3700–8500 Å and have signal-to-noise ratios in a range of 3–300. We report the discovery and observational properties of 161 AGNs in this footprint, which expands the total number of spectroscopically confirmed AGNs by MQS to 919. After the conversion of the OGLE mean magnitudes to the monochromatic luminosities at 5100, 3000, and 1350 Å, we were able to reliably measure the black hole masses for 165 out of 919 AGNs. The remaining physical parameters we provide are the bolometric luminosities and the Eddington ratios. A fraction of these AGNs have been observed by the OGLE survey since 1997 (all of them since 2001), enabling studies of correlations between the variability and physical parameters of these AGNs.
Weighted Stacking of Radio Images Affected by Noise and Interfering Signals
Authors: Murgia Giulia , Fatigoni Sofia 
Published: April 2024

Abstract
We implement an algorithm based on the weighted stacking of astronomical images that can combine different observations of the same region of the sky removing the interfering signals. We develop a C++ code that takes as input a set of spectral cubes and computes the local weights of the intensity for each pixel of every channel. The weights are calculated as the inverse variance of the nearby pixels and are used to compute the weighted merge of the input files. Astronomical sources, present in all cubes, are preserved by the weighted average. However, interfering signals, present in specific cubes and a certain frequency range, are down-weighted in the average and removed from the output spectral cube. We present the results obtained by analyzing simulated spectral cubes containing astronomical sources, noise, and a random set of interferences of different intensities and spectral occupations. The performance of the algorithm is evaluated by comparing the output result with the input sky-model image. Finally, we present the results obtained by applying the method to a set of real data consisting of observations of the Andromeda galaxy, Messier 31 (M31), at 6.6 GHz obtained with the Sardinia Radio Telescope.
Detection of Rydberg Lines from the Atmosphere of Betelgeuse
Authors: Dent W. R. F. , Harper G. M. , Richards A. M. S. , Kervella P. , Matthews L. D. 
Published: April 2024

Abstract
Emission lines from Rydberg transitions are detected for the first time from a region close to the surface of Betelgeuse. The H30α line is observed at 231.905 GHz, with an FWHM ∼42 km s−1 and extended wings. A second line at 232.025 GHz (FWHM ∼21 km s−1 ), is modeled as a combination of Rydberg transitions of abundant low first ionization potential metals. Both H30α and the Rydberg combined line X30α are fitted by Voigt profiles, and collisional broadening with electrons may be partly responsible for the Lorentzian contribution, indicating electron densities of a few 108 cm−3. X30α is located in a relatively smooth ring at a projected radius of 0.9× the optical photospheric radius R
⋆, whereas H30α is more clumpy, reaching a peak at ∼1.4 R
⋆. We use a semiempirical thermodynamic atmospheric model of Betelgeuse to compute the 232 GHz (1.29 mm) continuum and line profiles making simple assumptions. Photoionized abundant metals dominate the electron density, and the predicted surface of continuum optical depth unity at 232 GHz occurs at ∼1.3 R
⋆, in good agreement with observations. Assuming a Saha–Boltzmann distribution for the level populations of Mg, Si, and Fe, the model predicts that the X30α emission arises in a region of radially increasing temperature and turbulence. Inclusion of ionized C and non-LTE effects could modify the integrated fluxes and location of emission. These simulations confirm the identity of the Rydberg transition lines observed toward Betelgeuse and reveal that such diagnostics can improve future atmospheric models.
VADER: Probing the Dark Side of Dimorphos with LICIACube LUKE
Authors: Zinzi Angelo , Hasselmann P. H. A. , Della Corte V. , Deshapriya J. D. P. , Gai I. , Lucchetti A. , Pajola M. , Rossi A. , Dotto E. , Mazzotta Epifani E. , Daly R. T. , Hirabayashi M. , Farnham T. , Ernst C. M. , Ivanovski S. L. , Li J.-Y. , Parro L. M. , Amoroso M. , Beccarelli J. , Bertini I. , Brucato J. R. , Capannolo A. , Caporali S. , Ceresoli M. , Cremonese G. , Dall’Ora M. , Gomez Casajus L. , Gramigna E. , Ieva S. , Impresario G. , Lasagni Manghi R. , Lavagna M. , Lombardo M. , Modenini D. , Negri B. , Palumbo P. , Perna D. , Pirrotta S. , Poggiali G. , Tortora P. , Tusberti F. , Zannoni M. , Zanotti G. 
Published: April 2024

Abstract
The ASI cubesat LICIACube has been part of the first planetary defense mission DART, having among its scopes to complement the DRACO images to better constrain the Dimorphos shape. LICIACube had two different cameras, LEIA and LUKE, and to accomplish its goal, it exploited the unique possibility of acquiring images of the Dimorphos hemisphere not seen by DART from a vantage point of view, in both time and space. This work is indeed aimed at constraining the tridimensional shape of Dimorphos, starting from both LUKE images of the nonimpacted hemisphere of Dimorphos and the results obtained by DART looking at the impacted hemisphere. To this aim, we developed a semiautomatic Computer Vision algorithm, named VADER, able to identify objects of interest on the basis of physical characteristics, subsequently used as input to retrieve the shape of the ellipse projected in the LUKE images analyzed. Thanks to this shape, we then extracted information about the Dimorphos ellipsoid by applying a series of quantitative geometric considerations. Although the solution space coming from this analysis includes the triaxial ellipsoid found by using DART images, we cannot discard the possibility that Dimorphos has a more elongated shape, more similar to what is expected from previous theories and observations. The result of our work seems therefore to emphasize the unique value of the LICIACube mission and its images, making even clearer the need of having different points of view to accurately define the shape of an asteroid.
Freinet – Ferenczi
Authors: Prot Frédérique Marie 
Published: April 2024

Je propose dans cet article de partir du fameux texte de Ferenczi de 1908 dans lequel il appelle de ses vœux une réflexion et une évolution des pratiques scolaires car celles-ci, dit-il, « constituent un véritable bouillon de culture des névroses actuelles » (Ferenczi, 1908/1968, p. 51). Ce texte porte en germe des éléments sur lesquels Célestin Freinet s’est exprimé vingt ans plus tard, lors d’une conférence à Leipzig intitulée « La discipline parmi les écoliers », conférence dans laquelle il fait la critique de ce qu’il nomme la « discipline oppressive ». Il semble que la question cruciale que pose Ferenczi se retrouve dans des pratiques imaginées et mises en œuvre par Freinet : si l’éducation reçue des adultes joue un rôle non négligeable dans la pathologie ultérieure de chacun, quels moyens thérapeutique et prophylactique envisager contre de telles pratiques ? L’éducation dans le monde allemand du XIXe et début du XXe siècle à laquelle Ferenczi fait vraisemblablement allusion est un modèle éducatif problématique car brutal. Il annulait chez les plus jeunes toutes formes de désir et de volonté. C’est d’une certaine façon tout le dilemme de l’éducation que questionnent psychanalystes et pédagogues : l’apport structurant de l’adulte à l’enfant d’une nécessaire frustration qui permette d’en faire un adulte civilisé – mais comment ? La proposition de Freinet est claire, elle s’entend suivant deux grandes idées qu’il a développées par la suite : une nouvelle organisation de l’école et de la classe permettant de sortir du modèle d’une discipline « oppressive » pour s’acheminer vers un nouveau modèle de discipline qu’il qualifia de « discipline libératrice », entendue en tant que libération de l’enfant de certains troubles psychiques. Cette capacité à agir avec sollicitude pour l’éducateur peut s’entendre comme possibilité de faire preuve de tact dans la relation avec les enfants. Introduit par Ferenczi, le tact revêt toute son importance pour le pédagogue. En effet, dans la notion de tact chez Ferenczi, il y a l’idée de toucher par une parole juste et efficiente, permettant de dire sans blesser au moment opportun. Dans les deux courts épisodes issus d’une réunion de coopérative que je présente, je tente de montrer que les professeures peuvent faire preuve de tact.
The Performance of Chatbots and the AAPOS Website as a Tool for Amblyopia Education
Authors: Doğan Levent , Özçakmakcı Gazi Bekir , Yılmaz Ĭbrahim Edhem 
Published: April 2024

Purpose:
To evaluate the understandability, actionability, and readability of responses provided by the website of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS), ChatGPT-3.5, Bard, and Bing Chat about amblyopia and the appropriateness of the responses generated by the chatbots.

Method:
Twenty-five questions provided by the AAPOS website were directed three times to fresh ChatGPT-3.5, Bard, and Bing Chat interfaces. Two experienced pediatric ophthalmologists categorized the responses of the chatbots in terms of their appropriateness. Flesch Reading Ease (FRE), Flesch Kincaid Grade Level (FKGL), and Coleman-Liau Index (CLI) were used to evaluate the readability of the responses of the AAPOS website and chatbots. Furthermore, the understandability scores were evaluated using the Patient Education Materials Assessment Tool (PEMAT).

Results:

The appropriateness of the chatbots' responses was 84% for ChatGPT-3.5 and Bard and 80% for Bing Chat (
P
> .05). For understandability (mean PEMAT-U score AAPOS website: 81.5%, Bard: 77.6%, ChatGPT-3.5: 76.1%, and Bing Chat: 71.5%,
P
< .05) and actionability (mean PEMAT-A score AAPOS website: 74.6%, Bard: 69.2%, ChatGPT-3.5: 67.8%, and Bing Chat: 64.8%,
P
< .05), the AAPOs website scored better than the chat-bots. Three readability analyses showed that Bard had the highest mean score, followed by the AAPOS website, Bing Chat, and ChatGPT-3.5, and these scores were more challenging than the recommended level.

Conclusions:
Chatbots have the potential to provide detailed and appropriate responses at acceptable levels. The AAPOS website has the advantage of providing information that is more understandable and actionable. The AAPOS website and chatbots, especially Chat-GPT, provided difficult-to-read data for patient education regarding amblyopia.

[
J Pediatr Ophthalmol Strabismus
. 2024;61(5):325–331.]
De la scène à l’écran
Authors: Rossi Jérôme 
Published: April 2024

Quoiqu’initialement conçue pour la scène, c’est finalement sur le grand écran que sort, en 1937, l’opérette Prends la route du réalisateur Jean Boyer et du compositeur Georges Van Parys. La comparaison entre le film et le manuscrit de la pièce permet de documenter avec précision les stratégies d’adaptation musicale déployées par Van Parys pour passer de la scène à l’écran : suppression des ballets et des chœurs non reliés à l’action, composition d’une importante partition instrumentale, concentration des chansons sur les vedettes principales « Pils et Tabet », réduction du nombre de chansons et redéploiement de celles-ci dans le film avec des paroles adaptées aux circonstances.