adsabs/SciX_UAT_keywords huggingface dataset:
Constraining High-energy Neutrino Emission from Supernovae with IceCube

Core-collapse supernovae are a promising potential high-energy neutrino source class. We test for correlation between seven years of IceCube neutrino data and a catalog containing more than 1000 core-collapse supernovae of types IIn and IIP and a sample of stripped-envelope supernovae. We search both for neutrino emission from individual supernovae as well as for combined emission from the whole supernova sample, through a stacking analysis. No significant spatial or temporal correlation of neutrinos with the cataloged supernovae was found. All scenarios were tested against the background expectation and together yield an overall p-value of 93%; therefore, they show consistency with the background only. The derived upper limits on the total energy emitted in neutrinos are 1.7 × 1048 erg for stripped-envelope supernovae, 2.8 × 1048 erg for type IIP, and 1.3 × 1049 erg for type IIn SNe, the latter disfavoring models with optimistic assumptions for neutrino production in interacting supernovae. We conclude that stripped-envelope supernovae and supernovae of type IIn do not contribute more than 14.6% and 33.9%, respectively, to the diffuse neutrino flux in the energy range of about [ 103-105] GeV, assuming that the neutrino energy spectrum follows a power-law with an index of -2.5. Under the same assumption, we can only constrain the contribution of type IIP SNe to no more than 59.9%. Thus, core-collapse supernovae of types IIn and stripped-envelope supernovae can both be ruled out as the dominant source of the diffuse neutrino flux under the given assumptions.

Keywords: neutrino astronomy; core-collapse supernovae; circumstellar matter; high energy astrophysics
The Redshift and Star Formation Mode of AzTEC2: A Pair of Massive Galaxies at z = 4.63

We combine observations from the Atacama Large Millimeter/submillimeter Array and the NOrthern Extended Millimeter Array to assess the redshift and to study the star formation conditions in AzTEC2, one of the brightest submillimeter galaxies (SMGs) in the COSMOS field ( ${S}_{1.1\mathrm{mm}}=10.5\pm 1.4$ mJy). Our high-resolution observations confirm that AzTEC2 splits into two components (namely AzTEC2-A and AzTEC2-B) for which we detect [C II] and 12CO(5 → 4) line emission, implying a redshift of 4.626 ± 0.001 (4.633 ± 0.001) for AzTEC2-A (AzTEC2-B) and ruling out previous associations with a galaxy at $z\sim 1$ . We use the 12CO(5 → 4) line emission and adopt typical SMG-like gas excitation conditions to estimate the molecular gas mass, which is ${M}_{\mathrm{gas}}({\alpha }_{\mathrm{CO}}/2.5)=2.1\pm 0.4\,\times \,{10}^{11}\,{M}_{\odot }$ for AzTEC2-A, and a factor four lower for AzTEC2-B. With the infrared-derived star formation rate of AzTEC2-A ( $1920\pm 100\,{M}_{\odot }$ yr-1) and AzTEC2-B ( $710\pm 35\,{M}_{\odot }$ yr-1), they both will consume their current gas reservoir within (30-200) Myr. We find evidence of a rotation-dominated [C II] disk in AzTEC2-A, with a deprojected rotational velocity of ${V}_{\mathrm{rot}}(I=39^\circ )=660\pm 130$ km s-1, velocity dispersion $\lesssim 100$ km s-1, and dynamical mass of ${M}_{\mathrm{dyn}}(I=39^\circ )={2.6}_{-0.9}^{+1.2}\times {10}^{11}\,{M}_{\odot }$ . We propose that an elevated gas accretion rate from the cosmic web might be the main driver of the intense levels of star formation in AzTEC2-A, which might be further enhanced by gravitational torques induced by its minor companion (AzTEC2-B). These results strengthen the picture whereby the population of single-dish selected SMGs is rather heterogeneous, including a population of pairs of massive, highly active galaxies in a pre-coalescence phase.

Keywords: galaxies; galaxy evolution; galaxy formation; high-redshift galaxies; disk galaxies
The Formation of an Atypical Sunspot Light Bridge as a Result of Large-scale Flux Emergence

We use a combination of full-disk data from the Solar Dynamics Observatory and high-resolution data from the Dunn Solar Telescope (DST) to study the formation, structure, and evolution of an atypical light bridge (LB) in a regular sunspot. The LB results from the emergence of magnetic flux with one footpoint rooted in a pore outside the parent sunspot that appears about 17 hr before the LB. The pore has a polarity opposite to that of the sunspot and recedes from it at a speed of about 0.4 km s-1. This is accompanied by the development of an elongated magnetic channel in the outer penumbra that triggers the formation of the LB when it reaches the inner penumbral boundary. The LB is a nearly horizontal structure with a field strength of about 1.2 kG that exhibits long-lived photospheric blueshifts of about 0.85 km s-1 along its entire length. The emergence of the LB leads to dynamic surges in the chromosphere and transition region about 13 minutes later. We derive the photospheric and chromospheric structure of the LB in the DST data from spectral line parameters and inversions of He I at 1083 nm, Si I at 1082.7 nm, Ca II IR at 854 nm, and Hα at 656 nm and speckle-reconstructed imaging at 700 and 430 nm. The LB shows an elongated filamentary shape in the photosphere without lateral extrusions. The thermal inversion of Ca II IR reveals the LB to be about 600-800 K hotter than the umbra. Different sections of the LB are elevated to heights between 400 and 700 km. Our results indicate that LB formation is part of a flux emergence event with the LB envelope reaching a height of about 29 Mm before dissolving after about 13 hr. We conclude that the existence of persistent, large-scale photospheric blueshifts in LBs is the most likely criterion for distinguishing between flux emergence events and overturning convection in field-free umbral intrusions.

Keywords: sunspots; solar magnetic flux emergence; solar magnetic fields; solar photosphere; solar chromosphere; solar corona
Effects of Emerging Bipolar Magnetic Regions in Mean-field Dynamo Model of Solar Cycles 23 and 24

We model the physical parameters of Solar Cycles 23 and 24 using a nonlinear dynamical mean-field dynamo model that includes the formation and evolution of bipolar magnetic regions (BMRs). The Parker-type dynamo model consists of a complete MHD system in the mean-field formulation: the 3D magnetic induction equation, and 2D momentum and energy equations in the anelastic approximation. The initialization of BMRs is modeled in the framework of Parker's magnetic buoyancy instability. It defines the depths of BMR injections, which are typically located at the edge of the global dynamo waves. The distribution with longitude and latitude and the size of the initial BMR perturbations are taken from the NOAA database of active regions. The modeling results are compared with various observed characteristics of the solar cycles. Only the BMR perturbations located in the upper half of the convection zone lead to magnetic active regions on the solar surface. While the BMRs initialized in the lower part of the convection zone do not emerge on the surface, they still affect the global dynamo process. Our results show that BMRs can play a substantial role in the dynamo processes and affect the strength of the solar cycles. However, the data driven model shows that the BMR's effect alone cannot explain the weak Cycle 24. This weak cycle and the prolonged preceding minimum of magnetic activity were probably caused by a decrease of the turbulent helicity in the bulk of the convection zone during the decaying phase of Cycle 23.

Keywords: the sun; solar physics; solar magnetic fields
Search for Coincident Gravitational Waves and Long Gamma-Ray Bursts from 4-OGC and the Fermi-GBM/Swift-BAT Catalog

The recent discovery of a kilonova associated with an apparent long-duration gamma-ray burst has challenged the typical classification that long gamma-ray bursts originate from the core collapse of massive stars and short gamma-ray bursts are from compact binary coalescence. The kilonova indicates a neutron star merger origin and suggests the viability of gravitational-wave and long gamma-ray burst multimessenger astronomy. Gravitational waves play a crucial role by providing independent information for the source properties. This work revisits the archival 2015-2020 LIGO/Virgo gravitational-wave candidates from the 4-OGC catalog that are consistent with a binary neutron star or neutron star-black hole merger and the long-duration gamma-ray bursts from the Fermi-GBM and Swift-BAT catalogs. We search for spatial and temporal coincidence with up to a 10 s time lag between gravitational-wave candidates and the onset of long-duration gamma-ray bursts. The most significant candidate association has only a false-alarm rate of once every 2 yr; given the LIGO/Virgo observational period, this is consistent with a null result. We report an exclusion distance for each search candidate for a fiducial gravitational-wave signal with conservative viewing angle assumptions.

Keywords: gravitational wave astronomy; gamma-ray bursts
Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC3N, CH3CN, and c-C3H2

The precursors to larger, biologically relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. Here, we present 0"3 observations of HC3N, CH3CN, and c-C3H2 in five protoplanetary disks observed as part of the Molecules with ALMA at Planet-forming Scales (MAPS) Large Program. We robustly detect all molecules in four of the disks (GM Aur, AS 209, HD 163296, and MWC 480) with tentative detections of c-C3H2 and CH3CN in IM Lup. We observe a range of morphologies-central peaks, single or double rings-with no clear correlation in morphology between molecule or disk. Emission is generally compact and on scales comparable with the millimeter dust continuum. We perform both disk-integrated and radially resolved rotational diagram analysis to derive column densities and rotational temperatures. The latter reveals 5-10 times more column density in the inner 50-100 au of the disks when compared with the disk-integrated analysis. We demonstrate that CH3CN originates from lower relative heights in the disks when compared with HC3N, in some cases directly tracing the disk midplane. Finally, we find good agreement between the ratio of small to large nitriles in the outer disks and comets. Our results indicate that the protoplanetary disks studied here are host to significant reservoirs of large organic molecules, and that this planet- and comet-building material can be chemically similar to that in our own solar system. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Keywords: protoplanetary disks; astrochemistry; interstellar molecules; planet formation
Detection of Strong Epicyclic Density Spikes in the GD-1 Stellar Stream: An Absence of Evidence for the Influence of Dark Matter Subhalos?

The density variations in thin stellar streams may encode important information on the nature of dark matter. For instance, if dark matter aggregates into massive subhalos, these perturbers are expected to scatter stars out of dynamically cold stellar streams, possibly leading to detectable gaps in those structures. Here, we reexamine the density variations in the GD-1 stream, using Gaia Data Release 2 (DR2) astrometry and Panoramic Survey Telescope and Rapid Response System photometry, together with high-precision radial velocities measured with the Canada-France-Hawaii Telescope/ESPaDOnS and Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph instruments and complemented with public radial velocity catalogs. We show that after correcting for projection effects, the density profile exhibits high contrast periodic peaks, separated by 2.64 ± 0.18 kpc. An N-body simulation is presented that reproduces this striking morphology with simple epicyclic motion in a smooth Galactic potential. We also discuss the reliability of measuring density variations using ground-based photometric surveys, and for the particular case of GD-1 we highlight some of the artifacts present in the Gaia DR2 catalog along its track. Massive dark subhalos do not appear to be required to explain the density clumping along GD-1.

Keywords: milky way dynamics; stellar dynamics; hydrodynamics; milky way galaxy; milky way dark matter halo; dark matter
Fermi Large Area Telescope Performance after 10 Years of Operation

The Large Area Telescope (LAT), the primary instrument for the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view, high-energy gamma-ray telescope, covering the energy range from 30 MeV to more than 300 GeV. We describe the performance of the instrument at the 10 yr milestone. LAT performance remains well within the specifications defined during the planning phase, validating the design choices and supporting the compelling case to extend the duration of the Fermi mission. The details provided here will be useful when designing the next generation of high-energy gamma-ray observatories.

Keywords: gamma-ray telescopes; calibration
An Improved Magnetohydrodynamic Simulation of the 2006 December 13 Coronal Mass Ejection of NOAA Active Region 10930

We present a magnetohydrodynamic simulation of the coronal mass ejection on 2006 December 13 in the emerging δ-sunspot NOAA Active Region 10930, improving upon a previous simulation by Fan as follows. (1) Incorporate an ambient solar wind instead of using a static potential magnetic field extrapolation as the initial state. (2) In addition to imposing the emergence of a twisted flux rope, also impose at the lower boundary a random electric field that represents the effect of turbulent convection, which drives field-line braiding and produces resistive and viscous heating in the corona. With the inclusion of this heating, which depends on the magnetic field topology, we are able to model the synthetic soft X-ray images that would be observed by the X-Ray Telescope (XRT) of the Hinode satellite, produced by the simulated coronal magnetic field. We find that the simulated preeruption magnetic field with the buildup of a twisted magnetic flux rope produces synthetic soft X-ray emission that shows qualitatively similar morphology as that observed by the Hinode/XRT for both the ambient coronal loops of the active region and the central inverse S-shaped "sigmoid" that sharpens just before the onset of the eruption. The synthetic postflare loop brightening also shows similar morphology to that seen in the Hinode/XRT image during the impulsive phase of the eruption. It is found that the kinematics of the erupting flux rope is significantly affected by the open magnetic fields and fast solar wind streams adjacent to the active region.

Keywords: magnetohydrodynamics; magnetohydrodynamical simulations; solar coronal mass ejections; solar magnetic fields
The Molecular Clouds in a Section of the Third Galactic Quadrant: Observational Properties and Chemical Abundance Ratio between CO and its Isotopologues

We compare the observational properties between 12CO, 13CO, and C18O and summarize the observational parameters based on a 7069-cloud sample from the Milky Way Imaging Scroll Painting CO survey in a section of the third Galactic quadrant. We find that the 13CO angular area ( ${A}_{{}^{13}\mathrm{CO}}$ ) generally increases with that of 12CO ( ${A}_{{}^{12}\mathrm{CO}}$ ), and the ratio of ${A}_{{}^{13}\mathrm{CO}}$ to ${A}_{{}^{12}\mathrm{CO}}$ is 0.38 by linear fitting. We find that the 12CO and 13CO flux are tightly correlated as ${F}_{{}^{13}\mathrm{CO}}=0.17\,{F}_{{}^{12}\mathrm{CO}}$ with both fluxes calculated within the 13CO-bright region. This indicates that the abundance ${X}_{{}^{13}\mathrm{CO}}$ is a constant as ${6.5}_{-0.5}^{+0.1}\times {10}^{-7}$ for all samples under the assumption of local thermodynamic equilibrium (LTE). Additionally, we observed that the X-factor is approximately constant in a large sample of molecular clouds. Similarly, we find ${F}_{{{\rm{C}}}^{18}{\rm{O}}}=0.11\,{F}_{{}^{13}\mathrm{CO}}$ with both fluxes calculated within the C18O-bright region, which indicates that the abundance ratio ${X}_{{}^{13}\mathrm{CO}}/{X}_{{{\rm{C}}}^{18}{\rm{O}}}$ stays at the same value of ${9.7}_{-0.8}^{+0.6}$ across the molecular clouds under the LTE assumption. The linear relationships of ${F}_{{}^{12}\mathrm{CO}}$ versus ${F}_{{}^{13}\mathrm{CO}}$ and ${F}_{{}^{13}\mathrm{CO}}$ versus ${F}_{{{\rm{C}}}^{18}{\rm{O}}}$ hold not only for the 13CO-bright region and C18O-bright region, but also for the entire molecular cloud scale with a lower flux ratio. The abundance ratio ${X}_{{}^{13}\mathrm{CO}}/{X}_{{{\rm{C}}}^{18}{\rm{O}}}$ inside the clouds shows a strong correlation with the column density and temperature. This indicates that the ratio ${X}_{{}^{13}\mathrm{CO}}/{X}_{{{\rm{C}}}^{18}{\rm{O}}}$ is dominated by a combination of chemical fractionation, selective dissociation, and the self-shielding effect inside the clouds.

Keywords: molecular clouds; chemical abundances; abundance ratios
Magnetic Helicity Estimations in Models and Observations of the Solar Magnetic Field. IV. Application to Solar Observations

In this ISSI-supported series of studies on magnetic helicity in the Sun, we systematically implement different magnetic helicity calculation methods on high-quality solar magnetogram observations. We apply finite-volume, discrete flux tube (in particular, connectivity-based) and flux-integration methods to data from Hinode's Solar Optical Telescope. The target is NOAA Active Region 10930 during a 1.5-day interval in 2006 December that included a major eruptive flare (SOL2006-12-13T02:14X3.4). Finite-volume and connectivity-based methods yield instantaneous budgets of the coronal magnetic helicity, while the flux-integration methods allow an estimate of the accumulated helicity injected through the photosphere. The objectives of our work are twofold: a cross-validation of methods, as well as an interpretation of the complex events leading to the eruption. To the first objective, we find (i) strong agreement among the finite-volume methods, (ii) a moderate agreement between the connectivity-based and finite-volume methods, (iii) an excellent agreement between the flux-integration methods, and (iv) an overall agreement between finite-volume- and flux-integration-based estimates regarding the predominant sign and magnitude of the helicity. To the second objective, we are confident that the photospheric helicity flux significantly contributed to the coronal helicity budget and that a right-handed structure erupted from a predominantly left-handed corona during the X-class flare. Overall, we find that the use of different methods to estimate the (accumulated) coronal helicity may be necessary in order to draw a complete picture of an active region corona, given the careful handling of identified data (preparation) issues, which otherwise would mislead the event analysis and interpretation.

Keywords: solar magnetic fields; solar flares; solar coronal mass ejections; astronomy data analysis; astronomy data modeling
Rotational Characteristics of the Solar Transition Region Using SDO/AIA 304 Å Images

To date, the rotational characteristics of the solar transition region remain unclear. In this work, by applying the flux modulation method to the images derived from the Solar Dynamics Observatory/Atmospheric Imaging Assembly between 2011 and 2022 at 304 Å wavelength, we have studied the rotation of the solar transition region, and the results obtained are as follows. The solar transition region rotates differentially, while, from the perspective of the entire time interval, the rotation coefficients A and B are 14.39 (±0.08) and -1.61 (±0.15), respectively, and we find no prominent asymmetry in the average rotation rate of the northern and southern hemispheres. The solar transition region rotates fastest during the solar cycle maximum, and the average rotation rate follows the overall trend of solar activity. Both the equatorial rotation rate (represented by coefficient A) and the latitudinal gradient (represented by coefficient B) of the solar transition region are smaller than that of the solar chromosphere and the corona, indicating the solar transition region rotates more slowly and more rigidly than the other two layers, and we speculate that the solar chromosphere and corona seem to restrain the rotation of the solar transition region at the same time.

Keywords: solar transition region; solar activity; solar cycle; solar differential rotation; solar rotation
Protoplanetary Disk Birth in Massive Star-forming Clumps: The Essential Role of the Magnetic Field

Protoplanetary disks form through angular momentum conservation in collapsing dense cores. In this work, we perform the first simulations with a maximal resolution down to the astronomical unit (au) of protoplanetary disk formation, through the collapse of 1000 M⊙ clumps, treating self-consistently both non-ideal magnetohydrodynamics with ambipolar diffusion as well as radiative transfer in the flux-limited diffusion approximation including stellar feedback. Using the adaptive mesh-refinement code RAMSES, we investigate the influence of the magnetic field on the disks properties with three models. We show that, without magnetic fields, a population dominated by large disks is formed that is not consistent with Class 0 disk properties as estimated from observations. The inclusion of magnetic field leads, through magnetic braking, to a very different evolution. When it is included, small <50 au disks represent about half the population. In addition, about 70% of the stars have no disk in this case, which suggests that our resolution is still insufficient to preserve the smaller disks. With ambipolar diffusion, the proportion of small disks is also prominent and we report a flat mass distribution around 0.01-0.1M⊙ and a typical disk-to-star mass ratios of ~10-2-10-1. This work shows that the magnetic field and its evolution plays a prominent role in setting the initial properties of disk populations.

Keywords: star formation; protoplanetary disks; magnetohydrodynamics; radiative transfer; interstellar medium; molecular clouds; protostars
Inferring Type II-P Supernova Progenitor Masses from Plateau Luminosities

Connecting observations of core-collapse supernova explosions to the properties of their massive star progenitors is a long-sought, and challenging, goal of supernova science. Recently, Barker et al. presented bolometric light curves for a landscape of progenitors from spherically symmetric neutrino-driven core-collapse supernova (CCSN) simulations using an effective model. They find a tight relationship between the plateau luminosity of the Type II-P CCSN light curve and the terminal iron-core mass of the progenitor. Remarkably, this allows us to constrain progenitor properties with photometry alone. We analyze a large observational sample of Type II-P CCSN light curves and estimate a distribution of iron-core masses using the relationship of Barker et al. The inferred distribution matches extremely well with the distribution of iron-core masses from stellar evolutionary models and namely, contains high-mass iron cores that suggest contributions from very massive progenitors in the observational data. We use this distribution of iron-core masses to infer minimum and maximum masses of progenitors in the observational data. Using Bayesian inference methods to locate optimal initial mass function parameters, we find ${M}_{\min }={9.8}_{-0.27}^{+0.37}$ and ${M}_{\max }={24.0}_{-1.9}^{+3.9}$ solar masses for the observational data.

Keywords: core-collapse supernovae; supernovae; type ii supernovae; hydrodynamical simulations; astronomical simulations; radiative transfer; red supergiant stars; stellar mass functions; stellar masses