adsabs/SciX_UAT_keywords huggingface dataset:
No Evidence of the Significant Grain Growth but Tentative Discovery of Disk Substructure in a Disk around the Class I Protostar L1489 IRS

For revealing the first step of planet formation, it is important to understand how and when dust grains become larger in a disk around a protostar. To investigate the grain growth, we analyze dust continuum emission toward a disk around the Class I protostar L1489 IRS at 0.9 and 1.3 mm wavelengths obtained by the Atacama Large Millimeter/submillimeter Array. The dust continuum emission extends to a disk radius (r) of r ~ 300 au, and the spectral index (α) is derived to be α ~ 3.6 at a radius of r ~ 100-300 au, similar to the interstellar dust. Therefore, the grain growth does not occur significantly in the outer disk (r ~ 100-300 au). Furthermore, we tentatively identify a ring-like substructure at r ~ 90 au even though the spatial resolution and sensitivity are not enough to determine this structure. If this is the real ring structure, the ring position and small dust in the disk outer part are consistent with the idea of the growth front. These results suggest that the L1489 protostellar disk may be the beginning of planet formation.

Keywords: young stellar objects; planet formation; protostars; star formation; dust continuum emission
WISE 2150-7520AB: A Very Low-mass, Wide Comoving Brown Dwarf System Discovered through the Citizen Science Project Backyard Worlds: Planet 9

We report the discovery of WISE 2150-7520AB (W2150AB): a widely separated (∼341 au) very low-mass L1 + T8 co-moving system. The system consists of the previously known L1 primary 2MASS J21501592-7520367 and a newly discovered T8 secondary found at position 21:50:18.99-75:20:54.6 (MJD = 57947) using Wide-field Infrared Survey Explorer data via the Backyard Worlds: Planet 9 citizen science project. We present Spitzer ch1 and ch2 photometry (ch1-ch2 = 1.41 ± 0.04 mag) of the secondary and Folded-port InfraRed Echellette prism spectra of both components. The sources show no peculiar spectral or photometric signatures, indicating that each component is likely field age. Using all observed data and the Gaia DR2 parallax of 41.3593 ± 0.2799 mas for W2150A we deduce fundamental parameters of log(Lbol/L⊙) = -3.69 ± 0.01, Teff = 2118 ± 62 K, and an estimated mass = 72 ± 12 MJup for the L1 and log(Lbol/L⊙) = -5.64 ± 0.02, Teff = 719 ± 61 K, and an estimated mass = 34 ± 22 MJup for the T8. At a physical separation of ∼341 au this system has Ebin = 1041 erg, making it the lowest binding energy system of any pair with Mtot < 0.1 MSun not associated with a young cluster. It is equivalent in estimated mass ratio, Ebin, and physical separation to the ∼2 Myr M7.25 + M8.25 binary brown dwarf 2MASS J11011926-7732383AB (2M1101AB) found in the Chameleon star-forming region. W2150AB is the widest companion system yet observed in the field where the primary is an L dwarf or later.

Keywords: brown dwarfs; l dwarfs; substellar companion stars; astrometry; star formation; t dwarfs; late-type dwarf stars; stellar kinematics
Novel Model of an Ultra-stripped Supernova Progenitor of a Double Neutron Star

Recent discoveries of double neutron star (DNS) mergers and ultra-stripped supernovae (SNe) raise the questions of their origin and connection. We present the first 1D model of a DNS progenitor system that is calculated self-consistently until an ultra-stripped iron core collapse. We apply the MESA code starting from a post-common-envelope binary consisting of a 1.35 M⊙ NS and a 3.20 M⊙ zero-age main-sequence helium star and continue the modeling via Case BB Roche-lobe overflow until the infall velocity of the collapsing iron core exceeds 1000 km s-1. The exploding star has a total mass of ~1.90 M⊙, consisting of a ~0.29 M⊙ He-rich envelope embedding a CO core of ~1.61 M⊙ and an iron-rich core of ~1.50 M⊙. The resulting second-born NS has an estimated mass of ~1.44 M⊙, and we discuss the fate of the post-SN system, as well as the mild recycling of the first-born NS. Depending on the initial conditions, this family of systems is anticipated to reproduce the DNS mergers detected by the LIGO network.

Keywords: interacting binary stars; neutron stars; gravitational wave sources; x-ray binary stars; stellar evolution
Closure Statistics in Interferometric Data

Interferometric visibilities, reflecting the complex correlations between signals recorded at antennas in an interferometric array, carry information about the angular structure of a distant source. While unknown antenna gains in both amplitude and phase can prevent direct interpretation of these measurements, certain combinations of visibilities called closure phases and closure amplitudes are independent of antenna gains and provide a convenient set of robust observables. However, these closure quantities have subtle noise properties and are generally both linearly and statistically dependent. These complications have obstructed the proper use of closure quantities in interferometric analysis, and they have obscured the relationship between analysis with closure quantities and other analysis techniques such as self calibration. We review the statistics of closure quantities, noting common pitfalls that arise when approaching low signal to noise due to the nonlinear propagation of statistical errors. We then develop a strategy for isolating and fitting to the independent degrees of freedom captured by the closure quantities through explicit construction of linearly independent sets of quantities along with their noise covariance in the Gaussian limit, valid for moderate signal to noise, and we demonstrate that model fits have biased posteriors when this covariance is ignored. Finally, we introduce a unified procedure for fitting to both closure information and partially calibrated visibilities, and we demonstrate both analytically and numerically the direct equivalence of inference based on closure quantities to that based on self calibration of complex visibilities with unconstrained antenna gains.

Keywords: very long baseline interferometry; interferometry; radio interferometers; astrostatistics techniques; astrostatistics strategies; aperture synthesis
Presolar Stardust in Asteroid Ryugu

We have conducted a NanoSIMS-based search for presolar material in samples recently returned from C-type asteroid Ryugu as part of JAXA's Hayabusa2 mission. We report the detection of all major presolar grain types with O- and C-anomalous isotopic compositions typically identified in carbonaceous chondrite meteorites: 1 silicate, 1 oxide, 1 O-anomalous supernova grain of ambiguous phase, 38 SiC, and 16 carbonaceous grains. At least two of the carbonaceous grains are presolar graphites, whereas several grains with moderate C isotopic anomalies are probably organics. The presolar silicate was located in a clast with a less altered lithology than the typical extensively aqueously altered Ryugu matrix. The matrix-normalized presolar grain abundances in Ryugu are ${4.8}_{-2.6}^{+4.7}$ ppm for O-anomalous grains, ${25}_{-5}^{+6}$ ppm for SiC grains, and ${11}_{-3}^{+5}$ ppm for carbonaceous grains. Ryugu is isotopically and petrologically similar to carbonaceous Ivuna-type (CI) chondrites. To compare the in situ presolar grain abundances of Ryugu with CI chondrites, we also mapped Ivuna and Orgueil samples and found a total of 15 SiC grains and 6 carbonaceous grains. No O-anomalous grains were detected. The matrix-normalized presolar grain abundances in the CI chondrites are similar to those in Ryugu: ${23}_{-6}^{+7}$ ppm SiC and ${9.0}_{-3.6}^{+5.4}$ ppm carbonaceous grains. Thus, our results provide further evidence in support of the Ryugu-CI connection. They also reveal intriguing hints of small-scale heterogeneities in the Ryugu samples, such as locally distinct degrees of alteration that allowed the preservation of delicate presolar material.

Keywords: meteorites; interstellar dust; asteroids; small solar system bodies; circumstellar matter
Blind Prediction of the Returning Image of Supernova Refsdal from a New Lens Model of the Galaxy Cluster MACS J1149.5+2223

We present a preliminary gravitational lensing model for the galaxy-cluster MACS J1149.5+2223 constructed using a new, lensing-potential curving modeling method under development. Multiple images identified before 2015 are used to constrain the model, and we aim to provide a prediction of the relative time delay of the reappearance SN Refsdal before its final measurement is unblinded to us. The predicted time delay of S2-S4 and SX images of SN Refsdal relative to S1 are 9.13 ± 2.63 days, 5.58 ± 3.78 days, 18.98 ± 2.55 days and -332.35 ± 9.32 days, assuming H0 = 70 km s-1 Mpc-1. Our calculation of the uncertainties is currently under development, and those given above are expected to be underestimated, since they are derived from only a single, best-fitting model.

Keywords: strong gravitational lensing; supernovae; galaxy clusters
JWST-TST High Contrast: Achieving Direct Spectroscopy of Faint Substellar Companions Next to Bright Stars with the NIRSpec Integral Field Unit

The JWST NIRSpec integral field unit (IFU) presents a unique opportunity to observe directly imaged exoplanets from 3 to 5 μm at moderate spectral resolution (R ∼ 2700) and thereby better constrain the composition, disequilibrium chemistry, and cloud properties of their atmospheres. In this work, we present the first NIRSpec IFU high-contrast observations of a substellar companion that requires starlight suppression techniques. We develop specific data-reduction strategies to study faint companions around bright stars and assess the performance of NIRSpec at high contrast. First, we demonstrate an approach to forward model the companion signal and the starlight directly in the detector images, which mitigates the effects of NIRSpec's spatial undersampling. We demonstrate a sensitivity to planets that are 3 × 10‑6 fainter than their stars at 1″, or 3 × 10‑5 at 0.″3. Then, we implement a reference star point-spread function subtraction and a spectral extraction that does not require spatially and spectrally regularly sampled spectral cubes. This allows us to extract a moderate resolution (R ∼ 2,700) spectrum of the faint T dwarf companion HD 19467 B from 2.9 to 5.2 μm with a signal-to-noise ratio of ∼10 per resolution element. Across this wavelength range, HD 19467 B has a flux ratio varying between 10‑5 and 10‑4 and a separation relative to its star of 1.″6. A companion paper by Hoch et al. more deeply analyzes the atmospheric properties of this companion based on the extracted spectrum. Using the methods developed here, NIRSpec's sensitivity may enable direct detection and spectral characterization of relatively old (∼1 Gyr), cool (∼250 K), and closely separated (∼3–5 au) exoplanets that are less massive than Jupiter.

Keywords: direct imaging; high contrast spectroscopy; high resolution spectroscopy; near infrared astronomy; extrasolar gaseous giant planets
Active Galactic Nucleus Properties of ∼1 Million Member Galaxies of Galaxy Groups and Clusters at z < 1.4 Based on the Subaru Hyper Suprime-Cam Survey

Herein, we present the statistical properties of active galactic nuclei (AGNs) for approximately 1 million member galaxies of galaxy groups and clusters with 0.1 < cluster redshift (z cl) < 1.4 selected using the Subaru Hyper Suprime-Cam, the so-called CAMIRA clusters. In this research, we focused on the AGN power fraction (f AGN), which is defined as the proportion of the contribution of AGNs to the total infrared (IR) luminosity, L IR (AGN)/L IR, and examined how f AGN depends on (i) z cl and (ii) the distance from the cluster center. We compiled multiwavelength data using the ultraviolet–mid-IR range. Moreover, we performed spectral energy distribution fits to determine f AGN using the CIGALE code with the SKIRTOR AGN model. We found that (i) the value of f AGN in the CAMIRA clusters is positively correlated with z cl, with the correlation slope being steeper than that for field galaxies, and (ii) f AGN exhibits a high value at the cluster outskirts. These results indicate that the emergence of the AGN population depends on the redshift and environment and that galaxy groups and clusters at high redshifts are important in AGN evolution. Additionally, we demonstrated that cluster–cluster mergers may enhance AGN activity at the outskirts of particularly massive galaxy clusters. Our findings are consistent with a related study on the CAMIRA clusters that was based on the AGN number fraction.

Keywords: galaxy clusters; active galactic nuclei; infrared galaxies; spectral energy distribution; catalogs
Presupernova Evolution and Explosive Nucleosynthesis of Rotating Massive Stars. II. The Supersolar Models at [Fe/H] = 0.3

We present an extension of the set of models published in Limongi & Chieffi (2018) at metallicity 2 times solar, i.e., [Fe/H] = 0.3. The key physical properties of these models at the onset of core collapse are mainly due to the higher mass loss triggered by the higher metallicity: the supersolar metallicity (SSM) models reach core collapse with smaller He- and CO-core masses, while the amount of 12C left by the central He burning is higher. These results are valid for all the rotation velocities. The yields of the neutron-capture nuclei expressed per unit mass of oxygen (i.e., the X/O) are higher in the SSM models than in the SM ones in the nonrotating case, while the opposite occurs in the rotating models. The trend shown by the nonrotating models is the expected one, given the secondary nature of the neutron-capture nucleosynthesis. Vice versa, the counterintuitive trend obtained in the rotating models is the consequence of the higher mass loss present in the SSM models, removes the H-rich envelope faster than in the SM models while the stars are still in central He burning, dumping out the entanglement (activated by the rotation instabilities) and therefore conspicuous primary neutron-capture nucleosynthesis.

Keywords: massive stars; core-collapse supernovae; stellar rotation; stellar nucleosynthesis
Stars Stripped in Binaries: The Living Gravitational-wave Sources

Binary interaction can cause stellar envelopes to be stripped, which significantly reduces the radius of the star. The orbit of a binary composed of a stripped star and a compact object can therefore be so tight that the gravitational radiation the system produces reaches frequencies accessible to the Laser Interferometer Space Antenna (LISA). Two such stripped stars in tight orbits with white dwarfs are known so far (ZTF J2130+4420 and CD-30°11223), but many more are expected to exist. These binaries provide important constraints for binary evolution models and may be used as LISA verification sources. We develop a Monte Carlo code that uses detailed evolutionary models to simulate the Galactic population of stripped stars in tight orbits with either neutron star or white dwarf companions. We predict 0-100 stripped star + white dwarf binaries and 0-4 stripped star + neutron star binaries with a signal-to-noise ratio >5 after 10 yr of observations with LISA. More than 90% of these binaries are expected to show large radial velocity shifts of ≳200 $\,\mathrm{km}\,{{\rm{s}}}^{-1}$ , which are spectroscopically detectable. Photometric variability due to tidal deformation of the stripped star is also expected and has been observed in ZTF J2130+4420 and CD-30°11223. In addition, the stripped star + neutron star binaries are expected to be X-ray bright with LX ≳ 1033-1036 $\,\mathrm{erg}\,{{\rm{s}}}^{-1}$ . Our results show that stripped star binaries are promising multimessenger sources for the upcoming electromagnetic and gravitational wave facilities.

Keywords: compact binary stars; interacting binary stars; common envelope binary stars; gravitational wave sources; radial velocity; ellipsoidal variable stars; x-ray binary stars
PHANGS-JWST First Results: Mapping the 3.3 μm Polycyclic Aromatic Hydrocarbon Vibrational Band in Nearby Galaxies with NIRCam Medium Bands

We present maps of the 3.3 μm polycyclic aromatic hydrocarbon (PAH) emission feature in NGC 628, NGC 1365, and NGC 7496 as observed with the Near-Infrared Camera imager on JWST from the PHANGS-JWST Cycle 1 Treasury project. We create maps that isolate the 3.3 μm PAH feature in the F335M filter (F335MPAH) using combinations of the F300M and F360M filters for removal of starlight continuum. This continuum removal is complicated by contamination of the F360M by PAH emission and variations in the stellar spectral energy distribution slopes between 3.0 and 3.6 μm. We modify the empirical prescription from Lai et al. to remove the starlight continuum in our highly resolved galaxies, which have a range of starlight- and PAH-dominated lines of sight. Analyzing radially binned profiles of the F335MPAH emission, we find that between 5% and 65% of the F335M intensity comes from the 3.3 μm feature within the inner 0.5 r 25 of our targets. This percentage systematically varies from galaxy to galaxy and shows radial trends within the galaxies related to each galaxy's distribution of stellar mass, interstellar medium, and star formation. The 3.3 μm emission is well correlated with the 11.3 μm PAH feature traced with the MIRI F1130W filter, as is expected, since both features arise from C-H vibrational modes. The average F335MPAH/F1130W ratio agrees with the predictions of recent models by Draine et al. for PAHs with size and charge distributions shifted toward larger grains with normal or higher ionization.

Keywords: polycyclic aromatic hydrocarbons; interstellar dust; medium band photometry; james webb space telescope
A Scheme of Full Kinetic Particle-in-cell Algorithms for GPU Acceleration Using CUDA Fortran Programming

The emerging computable devices, graphical processing units (GPUs), are gradually applied in the simulations of space physics. In this paper, we introduce an approach that implements full kinetic particle-in-cell simulations on GPU architecture devices using the CUDA Fortran language programming for the first time. Using the latest high-performance computing NVIDIA GPUs, this program, which follows the second-order leap-frog iteration method, can speed up the computing process by a factor of 150-285 on a single device compared with the time cost of running with a single core of an Intel Xeon Gold processor. Our scheme improves fast accessibility to the simulation results and provides valuable assistance in studying the physical process.

Keywords: solar magnetic reconnection; gpu computing
SCExAO/CHARIS Near-infrared Integral Field Spectroscopy of the HD 15115 Debris Disk

We present new, near-infrared (1.1-2.4 μm) high-contrast imaging of the debris disk around HD 15115 with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system coupled with the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS). The SCExAO/CHARIS resolves the disk down to ρ ∼ 0"2 (rproj ∼ 10 au), a factor of ∼3-5 smaller than previous recent studies. We derive a disk position angle of PA ∼ 279°4-280°5 and an inclination of i ∼ 85°3-86.2°. While recent SPHERE/IRDIS imagery of the system could suggest a significantly misaligned two-ring disk geometry, CHARIS imagery does not reveal conclusive evidence for this hypothesis. Moreover, optimizing models of both one- and two-ring geometries using differential evolution, we find that a single ring having a Hong-like scattering phase function matches the data equally well within the CHARIS field of view (ρ ≲ 1″). The disk's asymmetry, well evidenced at larger separations, is also recovered; the west side of the disk appears, on average, around 0.4 mag brighter across the CHARIS bandpass between 0"25 and 1″. Comparing Space Telescope Imaging Spectrograph (STIS) 50CCD optical photometry (2000-10500 Å) with CHARIS near-infrared photometry, we find a red (STIS/50CCD-CHARIS broadband) color for both sides of the disk throughout the 0"4-1″ region of overlap, in contrast to the blue color reported at similar wavelengths for regions exterior to ∼2″. Further, this color may suggest a smaller minimum grain size than previously estimated at larger separations. Finally, we provide constraints on planetary companions and discuss possible mechanisms for the observed inner disk flux asymmetry and color.

Keywords: circumstellar disks; debris disks
PeV Photon and Neutrino Flares from Galactic Gamma-Ray Binaries

The high-energy radiation from short period binaries containing a massive star with a compact relativistic companion was detected from radio to TeV γ-rays. We show here that PeV regime protons can be efficiently accelerated in the regions of collision of relativistic outflows of a compact object with stellar winds in these systems. The accelerated proton spectra in the presented Monte Carlo model have an upturn in the PeV regime and can provide very hard spectra of sub-PeV photons and neutrinos by photomeson processes in the stellar radiation field. The recent report of a possible sub-PeV γ-ray flare in coincidence with a high-energy neutrino can be understood in the frame of this model. The γ-ray binaries may contribute substantially to the Galactic component of the detected high-energy neutrino flux.

Keywords: high-energy cosmic radiation; gamma-ray sources
A Spatially Resolved Survey of Distant Quasar Host Galaxies. II. Photoionization and Kinematics of the ISM

We present detailed observations of photoionization conditions and galaxy kinematics in 11 z = 1.39-2.59 radio-loud quasar host galaxies. Data were taken with the OSIRIS integral field spectrograph and the adaptive optics system at the W. M. Keck Observatory that targeted nebular emission lines (Hβ, [O III], Hα, [N II]) redshifted into the near-infrared (1-2.4 μm). We detect extended ionized emission on scales ranging from 1 to 30 kpc photoionized by stars, shocks, and active galactic nuclei (AGN). Spatially resolved emission-line ratios indicate that our systems reside off the star formation and AGN-mixing sequence on the Baldwin, Phillips, & Terlevich diagram at low redshift. The dominant cause of the difference between line ratios of low-redshift galaxies and our sample is due to lower gas-phase metallicities, which are 2-5× less compared to galaxies with AGN in the nearby universe. Using gas velocity dispersion as a proxy to stellar velocity dispersion and dynamical mass measurement through inclined disk modeling, we find that the quasar host galaxies are undermassive relative to their central supermassive black hole mass, with all systems residing off the local scaling (M•-&sgr;, M•-M*) relationship. These quasar host galaxies require substantial growth, up to an order of magnitude in stellar mass, to grow into present-day massive elliptical galaxies. Combining these results with part I of our sample paper, we find evidence for winds capable of causing feedback before the AGN host galaxies land on the local scaling relation between black hole and galaxy stellar mass, and before the enrichment of the interstellar medium to a level observed in local galaxies with AGN.

Keywords: radio loud quasars; galaxy winds; emission line galaxies; m-sigma relation; supermassive black holes; observational astronomy; astronomical techniques; near infrared astronomy