bluuebunny/crossref_metadata_2025_split huggingface dataset:
Revealing the Dynamic Magnetoionic Environments of Repeating Fast Radio Burst Sources through Multiyear Polarimetric Monitoring with CHIME/FRB
Authors: Mckinven R. , Gaensler B. M. , Michilli D. , Masui K. , Kaspi V. M. , Su J. , Bhardwaj M. , Cassanelli T. , Chawla P. , Dong F. (Adam) , Fonseca E. , Leung C. , Li D. Z. , Ng C. , Patel C. , Pearlman A. B. , Petroff E. , Pleunis Z. , Rafiei-Ravandi M. , Rahman M. , Sand K. R. , Shin K. , Stairs I. H. , Tendulkar S. 
Published: July 2023

Abstract
Fast radio bursts (FRBs) display a confounding variety of burst properties and host-galaxy associations. Repeating FRBs offer insight into the FRB population by enabling spectral, temporal, and polarimetric properties to be tracked over time. Here, we report on the polarized observations of 12 repeating sources using multiyear monitoring with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) over 400–800 MHz. We observe significant rotation measure (RM) variations from many sources in our sample, including RM changes of several hundred radians per square meter over month timescales from FRBs 20181119A, 20190303A, and 20190417A, and more modest RM variability (ΔRM ≲ few tens of radians per square meter) from FRBs 20181030A, 20190208A, 20190213B, and 20190117A over equivalent timescales. Several repeaters display a frequency-dependent degree of linear polarization that is consistent with depolarization via scattering. Combining our measurements of RM variations with equivalent constraints on DM variability, we estimate the average line-of-sight magnetic field strength in the local environment of each repeater. In general, repeating FRBs display RM variations that are more prevalent and/or extreme than those seen from radio pulsars in the Milky Way and the Magellanic Clouds, suggesting repeating FRBs and pulsars occupy distinct magnetoionic environments.
Dust Properties of 870 μm-selected Galaxies in GOODS-S
Authors: McKay S. J. , Barger A. J. , Cowie L. L. , Bauer F. E. , Rosenthal M. J. Nicandro 
Published: July 2023

Abstract
We analyze the dust properties of 57 870 μm-selected dusty star-forming galaxies in GOODS-S using new deep Atacama Large Millimeter/Submillimeter Array 1.2, 2, and 3 mm continuum imaging together with other far-infrared through millimeter data. We fit the spectral energy distributions (SEDs) with optically thin modified blackbodies to constrain the emissivity indices and effective dust temperatures, finding a median emissivity index of

β
=

1.78

−
0.25

+
0.43

and a median temperature of

T

d

=

33.6

−
5.4

+
12.1

K. We observe a negative correlation between β and T

d
. By testing several SED models, we determine that the derived emissivity indices can be influenced by opacity assumptions. Our temperature measurements are consistent with no evolution in dust temperature with redshift.
On Wave Interference in Planet Migration: Dead Zone Torques Modified by Active Zone Forcing
Authors: Chametla Raúl O. , Chrenko Ondřej , Lyra Wladimir , Turner Neal J. 
Published: July 2023

Abstract
We investigate planetary migration in the dead zone of a protoplanetary disk where there is a set of spiral waves propagating inward due to the turbulence in the active zone and the Rossby wave instability, which occurs at the transition between the dead and active zones. We perform global 3D unstratified magnetohydrodynamical simulations of a gaseous disk with the FARGO3D code, using weak gradients in the static resistivity profiles that trigger the formation of a vortex at the outer edge of the dead zone. We find that once the Rossby vortex develops, spiral waves in the dead zone emerge and interact with embedded, migrating planets by wave interference, which notably changes their migration. The inward migration becomes faster depending on the mass of the planet, due mostly to the constructive (destructive) interference between the outer (inner) spiral arm of the planet and the destruction of the dynamics of the horseshoe region by means of the set of background spiral waves propagating inward. The constructive wave interference produces a more negative Lindblad differential torque, which inevitably leads to an inward migration. Lastly, for massive planets embedded in the dead zone, we find that the spiral waves can create an asymmetric, wider, and deeper gap than in the case of α-disks and can prevent the formation of vortices at the outer edge of the gap. The latter could generate a faster or slower migration compared to the standard type-II migration.
All-sky Faint DA White Dwarf Spectrophotometric Standards for Astrophysical Observatories: The Complete Sample
Authors: Axelrod Tim , Saha Abhijit , Matheson Thomas , Olszewski Edward W. , Bohlin Ralph C. , Calamida Annalisa , Claver Jenna , Deustua Susana , Holberg Jay B. , Hubeny Ivan , Mackenty John W. , Malanchev Konstantin , Narayan Gautham , Points Sean , Rest Armin , Sabbi Elena , Stubbs Christopher W. 
Published: July 2023

Abstract
Hot DA white dwarfs (DAWDs) have fully radiative pure hydrogen atmospheres that are the least complicated to model. Pulsationally stable, they are fully characterized by their effective temperature T
eff and surface gravity

log

g

, which can be deduced from their optical spectra and used in model atmospheres to predict their spectral energy distributions (SEDs). Based on this, three bright DAWDs have defined the spectrophotometric flux scale of the CALSPEC system of the Hubble Space Telescope (HST). In this paper we add 32 new fainter (16.5 < V < 19.5) DAWDs spread over the whole sky and within the dynamic range of large telescopes. Using ground-based spectra and panchromatic photometry with HST/WFC3, a new hierarchical analysis process demonstrates consistency between model and observed fluxes above the terrestrial atmosphere to <0.004 mag rms from 2700 to 7750 Å and to 0.008 mag rms at 1.6 μm for the total set of 35 DAWDs. These DAWDs are thus established as spectrophotometric standards with unprecedented accuracy from the near-ultraviolet to the near-infrared, suitable for both ground- and space-based observatories. They are embedded in existing surveys like the Sloan Digital Sky Survey, Pan-STARRS, and Gaia, and will be naturally included in the Large Synoptic Survey Telescope survey by the Rubin Observatory. With additional data and analysis to extend the validity of their SEDs further into the infrared, these spectrophotometric standard stars could be used for JWST, as well as for the Roman and Euclid observatories.
The Next Generation Virgo Cluster Survey (NGVS). XXXV. First Kinematical Clues of Overly Massive Dark Matter Halos in Several Ultradiffuse Galaxies in the Virgo Cluster
Authors: Toloba Elisa , Sales Laura V. , Lim Sungsoon , Peng Eric W. , Guhathakurta Puragra , Roediger Joel , Wang Kaixiang , Mihos J. Christopher , Côté Patrick , Durrell Patrick R. , Ferrarese Laura 
Published: July 2023

Abstract
We present Keck/DEIMOS spectroscopy of the first complete sample of ultradiffuse galaxies (UDGs) in the Virgo cluster. We select all UDGs in Virgo that contain at least 10 globular cluster (GC) candidates and are more than 2.5σ outliers in scaling relations of size, surface brightness, and luminosity (a total of 10 UDGs). We use the radial velocity of their GC satellites to measure the velocity dispersion of each UDG. We find a mixed bag of galaxies, from one UDG that shows no signs of dark matter, to UDGs that follow the luminosity–dispersion relation of early-type galaxies, to the most extreme examples of heavily dark matter–dominated galaxies that break well-known scaling relations such as the luminosity–dispersion or U-shaped total mass-to-light ratio relations. This is indicative of a number of mechanisms at play forming these peculiar galaxies. Some of them may be the most extended version of dwarf galaxies, while others are so extreme that they seem to populate dark matter halos consistent with that of the Milky Way or even larger. Even though Milky Way stars and other GC interlopers contaminating our sample of GCs cannot be fully ruled out, our assessment of this potential problem and simulations indicate that the probability is low and, if present, unlikely to be enough to explain the extreme dispersions measured. Further confirmation from stellar kinematics studies in these UDGs would be desirable. The lack of such extreme objects in any of the state-of-the-art simulations opens an exciting avenue of new physics shaping these galaxies.
Interplanetary Shocks between 0.3 and 1.0 au: Helios 1 and 2 Observations
Authors: Hajra Rajkumar , Tsurutani Bruce T. , Lakhina Gurbax S. , Lu Quanming , Du Aimin , Shan Lican 
Published: July 2023

Abstract
The Helios 1 (H1) and Helios 2 (H2) spacecraft measured the solar winds at a distance between ∼0.3 and 1.0 au from the Sun. With increasing heliocentric distance (r
h), the plasma speed is found to increase at ∼34–40 km s−1 au−1 and the density exhibits a sharper fall (

r

h

−
2

) compared to the magnetic field magnitude (

r

h

−
1.5

) and the temperature (

r

h

−
0.8

). Using all available solar wind plasma and magnetic field measurements, we identified 68 and 39 fast interplanetary shocks encountered by H1 and H2, respectively. The overwhelming majority (85%) of the shocks are found to be driven by interplanetary coronal mass ejections (ICMEs). While the two spacecraft encountered more than 73 solar wind high-speed streams (HSSs), only ∼22% had shocks at the boundaries of corotating interaction regions (CIRs) formed by the HSSs. All of the ICME shocks were found to be fast forward (FF) shocks; only four of the CIR shocks were fast reverse shocks. Among all ICME FF shocks (CIR FF shocks), 60% (75%) are quasi-perpendicular with shock normal angles (θ
Bn) ≥ 45° relative to the upstream ambient magnetic field, and 40% (25%) are quasi-parallel (θ
Bn < 45°). No radial dependences were found in FF shock normal angle and speed. The FF shock Mach number (M
ms), magnetic field, and plasma compression ratios are found to increase with increasing r
h at the rates of 0.72, 0.89, and 0.98 au−1, respectively. On average, ICME FF shocks are found to be considerably faster (∼20%) and stronger (with ∼28% higher M
ms) than CIR FF shocks.
Morphologies of Galaxies at z ≳ 9 Uncovered by JWST/NIRCam Imaging: Cosmic Size Evolution and an Identification of an Extremely Compact Bright Galaxy at z ∼ 12
Authors: Ono Yoshiaki , Harikane Yuichi , Ouchi Masami , Yajima Hidenobu , Abe Makito , Isobe Yuki , Shibuya Takatoshi , Wise John H. , Zhang Yechi , Nakajima Kimihiko , Umeda Hiroya 
Published: July 2023

Abstract
We present morphologies of galaxies at z ≳ 9 resolved by JWST/NIRCam 2–5 μm imaging. Our sample consists of 22 galaxy candidates identified by stringent dropout and photo-z criteria in GLASS, CEERS, SMACS J0723, and Stephan’s Quintet flanking fields, one of which has been spectroscopically identified at z = 11.44. We perform surface brightness (SB) profile fitting with GALFIT for six bright galaxies with a signal-to-noise ratio = 10–40 on an individual basis and for stacked faint galaxies with secure point-spread functions (PSFs) of the NIRCam real data, carefully evaluating systematics by Monte Carlo simulations. We compare our results with those of previous JWST studies, and confirm that the effective radii r
e of our measurements are consistent with those of previous measurements at z ∼ 9. We obtain r
e ≃ 200–300 pc with the exponential-like profiles, Sérsic indexes of n ≃ 1–1.5, for galaxies at z ∼ 12–16, indicating that the relation of r
e ∝ (1 + z)
s
for

s
=
−

1.22

−
0.16

+
0.17

explains cosmic evolution over z ∼ 0–16 for

∼

L

z
=
3

*

galaxies. One bright (M
UV = −21 mag) galaxy at z ∼ 12, GL-z12-1, has an extremely compact profile with r
e = 39 ± 11 pc that is surely extended over the PSF. Even in the case that the GL-z12-1 SB is fit by active galactic nuclei + galaxy composite profiles, the best-fit galaxy component is again compact,

r

e

=

48

−
15

+
38

pc, which is significantly (>5σ) smaller than the typical r
e value at z ∼ 12. Compared with numerical simulations, we find that such a compact galaxy naturally forms at z ≳ 10, and that frequent mergers at the early epoch produce more extended galaxies following the r
e ∝ (1 + z)
s
relation.
The Radial Distribution of Ion-scale Waves in the Inner Heliosphere
Authors: Liu Wen , Zhao Jinsong , Wang Tieyan , Dong Xiangcheng , Kasper Justin C. , Bale Stuart D. , Shi Chen , Wu Dejin 
Published: July 2023

Abstract
Determining the mechanism responsible for plasma heating and particle acceleration is a fundamental problem in the study of the heliosphere. Due to efficient wave–particle interactions of ion-scale waves with charged particles, these waves are widely believed to be a major contributor to ion energization, and their contribution considerably depends on the wave occurrence rate. By analyzing the radial distribution of quasi-monochromatic ion-scale waves observed by the Parker Solar Probe, this work shows that the wave occurrence rate is significantly enhanced in the near-Sun solar wind, specifically 21%–29% below 0.3 au, in comparison to 6%–14% beyond 0.3 au. The radial decrease of the wave occurrence rate is not only induced by the sampling effect of a single spacecraft detection, but also by the physics relating to the wave excitation, such as the enhanced ion beam instability in the near-Sun solar wind. This work also shows that the wave normal angle θ, the absolute value of ellipticity ϵ, the wave frequency f normalized by the proton cyclotron frequency f
cp, and the wave amplitude δ
B normalized by the local background magnetic field B
0 slightly vary with the radial distance. The median values of θ, ∣ϵ∣, f, and δ
B are about 9°, 0.73, 3f
cp, and 0.01B
0, respectively. Furthermore, this study proposes that the wave mode natures of the observed left-handed and right-handed polarized waves correspond to the Alfvén ion cyclotron mode wave and the fast magnetosonic whistler mode wave, respectively.
Environmental Dependence of the Mass–Metallicity Relation in Cosmological Hydrodynamical Simulations
Authors: Wang Kai , Wang Xin , Chen Yangyao 
Published: July 2023

Abstract
We investigate the environmental dependence of the gas-phase metallicity for galaxies at z = 0 to z ≳ 2 and the underlying physical mechanisms driving this dependence using state-of-the-art cosmological hydrodynamical simulations. We find that, at fixed stellar mass, central galaxies in massive halos have lower gas-phase metallicity than those in low-mass halos, while satellite galaxies residing in more massive halos are more metal-rich. The combined effect is that massive galaxies are more metal-poor in massive halos and low-mass galaxies are more metal-rich in massive halos. By inspecting the environmental dependence of other galaxy properties, we identify that the accretion of low-metallicity gas is responsible for the environmental dependence of central galaxies at high z, whereas the AGN feedback processes play a crucial role at low z. For satellite galaxies, we find that both the suppression of gas accretion and the stripping of existing gas are responsible for their environmental dependence, with negligible effect from the AGN feedback. Finally, we show that the difference of gas-phase metallicity as a function of stellar mass between protocluster and field galaxies agrees with recent observational results, for example from the MAMMOTH-Grism survey.
Scattering of Ions at a Rippled Shock
Authors: Gedalin Michael , Pogorelov Nikolai V. , Roytershteyn Vadim 
Published: July 2023

Abstract
In a collisionless shock the energy of the directed flow is converted to heating and acceleration of charged particles, and to magnetic compression. In low-Mach number shocks the downstream ion distribution is made of directly transmitted ions. In higher-Mach number shocks ion reflection is important. With the increase of the Mach number, rippling develops, which is expected to affect ion dynamics. Using ion tracing in a model shock front, downstream distributions of ions are analyzed and compared for a planar stationary shock with an overshoot and a similar shock with ripples propagating along the shock front. It is shown that rippling results in the distributions, which are substantially broader and more diffuse in the phase space. Gyrotropization is sped up. Rippling is able to generate backstreaming ions, which are absent in the planar stationary case.
Void Lensing in Cubic Galileon Gravity
Authors: Su Chen , Shan Huanyuan , Zhang Jiajun , Zhao Cheng , Yu Jiaxi , Wang Qiao , Xiao Linfeng , Liu Xiangkun , Zhao An 
Published: July 2023

Abstract
Weak-lensing studies via cosmic voids are a promising probe of modified gravity (MG). The excess surface mass density (ESD) is widely used as a lensing statistic in weak-lensing research. In this paper, we use the ray-tracing method to study the ESD around voids in simulations based on cubic Galileon (CG) gravity. With the compilation of an N-body simulation and the ray-tracing method, changes in structure formation and deflection angle resulting from MG can both be considered, making the extraction of lensing signals more realistic. We find good agreements between the measurement and theoretical prediction of ESD for CG gravity. However, the lensing signals are much less affected by the change in the deflection angle than by the change in the structure formation, indicating a good approximation of the ESD (statistics) as the projection of the 3D dark matter density field. Finally, we demonstrate that it is impossible to distinguish CG and general relativity in our simulation, but in the next-generation survey, thanks to the large survey area and the increased galaxy number density, detecting the differences between these two models is possible. The method employed in this paper, which combines an N-body simulation and the ray-tracing method, can be a robust way to measure the lensing signals from simulations based on the MGs, and especially on that which significantly modifies the deflection angle.
Lepto-hadronic Interpretation of 2021 RS Ophiuchi Nova Outburst
Authors: De Sarkar Agnibha , A. J. Nayana , Roy Nirupam , Razzaque Soebur , Anupama G. C. 
Published: July 2023

Abstract
Very-high-energy (VHE; 100 GeV < E ≤ 100 TeV) and high-energy (HE; 100 MeV < E ≤ 100 GeV) gamma rays were observed from the symbiotic recurrent nova RS Ophiuchi (RS Oph) during its outburst in 2021 August by various observatories, such as the High Energy Stereoscopic System (HESS), Major Atmospheric Gamma Imaging Cherenkov (MAGIC), and Fermi-Large Area Telescope (LAT). The models that have been explored so far tend to favor a hadronic scenario of particle acceleration over an alternative leptonic scenario. This paper explores a time-dependent lepto-hadronic scenario to explain the emission from the RS Oph source region. We have used simultaneous low-frequency radio data observed by various observatories along with the data provided by HESS, MAGIC, and Fermi-LAT to explain the multiwavelength spectral energy distributions corresponding to 4 days after the outburst. Our results show that a lepto-hadronic interpretation of the source not only explains the observed HE-VHE gamma-ray data but the corresponding model synchrotron component is also consistent with the first 4 days of low-radio-frequency data, indicating the presence of nonthermal radio emission at the initial stage of the nova outburst. We have also calculated the expected neutrino flux from the source region and discuss the possibility of detecting neutrinos.
Richardson–Lucy Deconvolution with a Spatially Variant Point-spread Function of Chandra: Supernova Remnant Cassiopeia A as an Example
Authors: Sakai Yusuke , Yamada Shinya , Sato Toshiki , Hayakawa Ryota , Higurashi Ryota , Kominato Nao 
Published: July 2023

Abstract
Richardson–Lucy (RL) deconvolution is one of the classical methods widely used in X-ray astronomy and other areas. Amid recent progress in image processing, RL deconvolution still leaves much room for improvement under realistic situations. One direction is to include the positional dependence of a point-spread function (PSF), so-called RL deconvolution with a spatially variant PSF (RLsv). Another is the method of estimating a reliable number of iterations and their associated uncertainties. We developed a practical method that incorporates the RLsv algorithm and the estimation of uncertainties. As a typical example of bright and high-resolution images, the Chandra X-ray image of the supernova remnant Cassiopeia A was used in this paper. RLsv deconvolution enables us to uncover the smeared features in the forward/backward shocks and jet-like structures. We constructed a method to predict the appropriate number of iterations using statistical fluctuation of the observed images. Furthermore, the uncertainties were estimated by error propagation from the last iteration, which was phenomenologically tested with the observed data. Thus, our method is a practically efficient framework to evaluate the time evolution of the remnants and their fine structures embedded in high-resolution X-ray images.
Three solutions for a three-point boundary value problem with instantaneous and non-instantaneous impulses
Authors: Zhang Huiping , Yao Wangjin 
Published: July 2023

<abstract><p>In this paper, we consider the multiplicity of solutions for the following three-point boundary value problem of second-order $ p $-Laplacian differential equations with instantaneous and non-instantaneous impulses:</p>

<p><disp-formula> <label/> <tex-math id="FE1"> \begin{document}$ \begin{equation*} \left\{ {\begin{array}{l}	-(\rho(t)\Phi_{p} (u'(t)))'+g(t)\Phi_{p}(u(t))=\lambda f_{j}(t,u(t)),\quad t\in(s_{j},t_{j+1}],\; j=0,1,...,m,\\	\Delta (\rho (t_{j})\Phi_{p}(u'(t_{j})))=\mu I_{j}(u(t_{j})), \quad j=1,2,...,m,\\	\rho (t)\Phi_{p} (u'(t))=\rho(t_{j}^{+}) \Phi_{p} (u'(t_{j}^{+})),\quad t\in(t_{j},s_{j}],\; j=1,2,...,m,\\	\rho(s_{j}^{+})\Phi_{p} (u'(s_{j}^{+}))=\rho(s_{j}^{-})\Phi_{p} (u'(s_{j}^{-})),\quad j=1,2,...,m,\\	u(0)=0, \quad u(1)=\zeta u(\eta), \end{array}} \right. \end{equation*} $\end{document} </tex-math> </disp-formula></p>
<p>where $ \Phi_{p}(u): = |u|^{p-2}u, \; p &gt; 1, \; 0 = s_{0} &lt; t_{1} &lt; s_{1} &lt; t_{2} &lt; ... &lt; s_{m_{1}} &lt; t_{m_{1}+1} = \eta &lt; ... &lt; s_{m} &lt; t_{m+1} = 1, \; \zeta &gt; 0, \; 0 &lt; \eta &lt; 1 $, $ \Delta (\rho (t_{j})\Phi_{p}(u'(t_{j}))) = \rho (t_{j}^{+})\Phi_{p}(u'(t_{j}^{+}))-\rho (t_{j}^{-})\Phi_{p}(u'(t_{j}^{-})) $ for $ u'(t_{j}^{\pm}) = \lim\limits_{t\to t_{j}^{\pm}}u'(t) $, $ j = 1, 2, ..., m $, and $ f_{j}\in C((s_{j}, t_{j+1}]\times\mathbb{R}, \mathbb{R}) $, $ I_{j}\in C(\mathbb{R}, \mathbb{R}) $. $ \lambda\in (0, +\infty) $, $ \mu\in\mathbb{R} $ are two parameters. $ \rho(t)\geq 1 $, $ 1\leq g(t)\leq c $ for $ t\in (s_{j}, t_{j+1}] $, $ \rho(t), \; g(t)\in L^{p}[0, 1] $, and $ c $ is a positive constant. By using variational methods and the critical points theorems of Bonanno-Marano and Ricceri, the existence of at least three classical solutions is obtained. In addition, several examples are presented to illustrate our main results.</p></abstract>