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Reconstructing the genesis of a globular cluster system at a look-back time of 9.1 Gyr with the JWST
Forbes, Duncan A.; Romanowsky, Aaron J.
Using early-release data from the JWST, Mowla et al. and Claeyssens et al. recently measured various properties for gravitationally lensed compact sources ('sparkles') around the 'Sparkler' galaxy at a redshift of 1.378 (a look-back time of 9.1 Gyr). Here, we focus on the Mowla et al. as they were able to break the age-metallicity degeneracy and d…
Strong and Rapid X-Ray Variability of the Super-Eddington Accreting Quasar SDSS J081456.10+532533.5
Brandt, W. N.; Garmire, Gordon P.; Luo, Bin +6 more
We report strong and rapid X-ray variability found from the super-Eddington accreting quasar SDSS J081456.10+532533.5 at z = 0.1197. It has a black hole mass of 2.7 × 107 M ⊙ and a dimensionless accretion rate of ≈4 measured from reverberation-mapping observations. It showed weak X-ray emission in the 2021 February Chandra ob…
Denoising Diffusion Probabilistic Models to Predict the Density of Molecular Clouds
Xu, Duo; Tan, Jonathan C.; Hsu, Chia-Jung +1 more
We introduce the state-of-the-art deep-learning denoising diffusion probabilistic model as a method to infer the volume or number density of giant molecular clouds (GMCs) from projected mass surface density maps. We adopt magnetohydrodynamic simulations with different global magnetic field strengths and large-scale dynamics, i.e., noncolliding and…
Time series analysis of bright TESS RRc stars: additional modes, phase variations, and more
Pál, A.; Plachy, E.; Molnár, L. +3 more
Using two years of data from the TESS space telescope, we have investigated the time series of 633 overtone pulsating field RR Lyrae (RRc) stars. The majority of stars (82.8 per cent) contain additional frequencies beyond the main pulsation. In addition to the frequencies previously explained by the ℓ = 8 and 9 non-radial modes, we have identified…
Photometric Calibrations of M-dwarf Metallicity with Markov Chain Monte Carlo and Bayesian Inference
Caballero, J. A.; Montes, D.; Duque-Arribas, C. +3 more
Knowledge of stellar atmospheric parameters (T eff, $\mathrm{log}g$ , [Fe/H]) of M dwarfs can be used to constrain both theoretical stellar models and Galactic chemical evolutionary models, and guide exoplanet searches, but their determination is difficult due to the complexity of the spectra of their cool atmospheres. In our ongoing ef…
X-ray and optical spectroscopic study of a γ Cassiopeiae analog source π Aquarii
Tsujimoto, Masahiro; Hayashi, Takayuki; Morihana, Kumiko +1 more
γ Cas analog sources are a subset of Be stars that emit intense and hard X-ray emission. Two competing ideas for their X-ray production mechanism are (a) the magnetic activities of the Be star and its disk and (b) the accretion from the Be star to an unidentified compact object. Among such sources, π Aqr plays a pivotal role as it is one of the on…
The X-Ray Binary-star Cluster Connection in Late-type Galaxies
Chandar, Rupali; Maccarone, Thomas J.; Thilker, David A. +3 more
We conduct one of the largest systematic investigations of bright X-ray binaries (XRBs) in both young star clusters and ancient globular clusters (GCs) using a sample of six nearby star-forming galaxies. Combining complete CXO X-ray source catalogs with optical Physics at High Angular Resolution in Nearby Galaxies-Hubble Space Telescope cluster ca…
Non-thermal Broadening of IRIS Fe XXI Line Caused by Turbulent Plasma Flows in the Magnetic Reconnection Region During Solar Eruptions
Reeves, Katharine K.; Polito, Vanessa; Chen, Bin +3 more
Magnetic reconnection is the key mechanism for energy release in solar eruptions, where the high-temperature emission is the primary diagnostic for investigating the plasma properties during the reconnection process. Non-thermal broadening of high-temperature lines has been observed in both the reconnection current sheet (CS) and flare loop-top re…
Star-forming site RAFGL 5085: Is a perfect candidate of hub-filament system?
Dewangan, L. K.; Pandey, Rakesh; Sharma, Saurabh +4 more
To investigate the star-formation process, we present a multi-wavelength study of a massive star-forming site RAFGL 5085, which has been associated with the molecular outflow, HII region and near-infrared cluster. The continuum images at 12, 250, 350 and 500
Environmental Impacts on the Rest-frame UV Size and Morphology of Star-forming Galaxies at z 2
Koyama, Yusei; Kodama, Tadayuki; Shimakawa, Rhythm +1 more
We report the measurement of rest-frame UV size and morphology of Hα-emission-selected star-forming galaxies (HAEs) in four protoclusters at z ~ 2 (PKS 1138-262, USS 1558-003, PHz G237.0+42.5, and CC 2.2) using archival Hubble Space Telescope Advanced Camera Survey (HST/ACS) F814W data. We compare the measurement of 122 HAEs in protoclusters detec…