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Morphology of Molecular Clouds at Kiloparsec Scale in the Milky Way: Shear-induced Alignment and Vertical Confinement
Li, Guang-Xing; Chen, Bing-Qiu; Xie, Yi-Heng
The shape of the cold interstellar molecular gas is determined by several processes, including self-gravity, tidal force, turbulence, magnetic field, and galactic shear. Based on the 3D dust extinction map derived by Vergely et al., we identify a sample of 550 molecular clouds within 3 kpc of the solar vicinity in the Galactic disk. Our sample con…
Three-stage Acceleration of Solar Energetic Particles Detected by Parker Solar Probe
Li, Chuan; Chen, Xiaomin
Coronal mass ejections (CMEs) drive powerful shocks and thereby accelerate solar energetic particles (SEPs) as they propagate from the corona into interplanetary space. Here we present the processes of three-stage particle acceleration by a CME-driven shock detected by the in situ spacecraft—Parker Solar Probe (PSP) on 2022 August 27. The onset of…
XMM-Newton High-resolution Spectroscopy of EXO 0748–676 after Its Reemergence from a Long Quiescence
Bhattacharya, Sayantan; Bhattacharyya, Sudip; Shaw, Gargi
EXO 0748–676 is a well-studied, high-inclination, dipping and eclipsing neutron star low-mass X-ray binary that has recently emerged from 16 yr of quiescence into a new outburst. We present results from 55.5 ks of XMM-Newton observation, focusing on high-resolution spectroscopy with the same instrument (the Reflection Grating Spectrometer) that pr…
Stripe 82-XL: The ∼54.8 deg2 and ∼18.8 Ms Chandra and XMM-Newton Point-source Catalog and Number of Counts
Marchesi, Stefano; LaMassa, Stephanie; Urry, C. Megan +9 more
We present an enhanced version of the publicly available Stripe 82X catalog (S82-XL), featuring a comprehensive set of 22,737 unique X-ray point sources identified with a significance ≳4σ. This catalog is four times larger than the original Stripe 82X catalog, by including additional archival data from the Chandra and XMM-Newton telescopes. Now co…
The Absolute Age of NGC 3201 Derived from Detached Eclipsing Binaries and the Hess Diagram
Chaboyer, Brian; Ying, Jiaqi (Martin); Du, Wenxin
We estimate the absolute age of the globular cluster NGC 3201 using 10,000 sets of theoretical isochrones constructed through Monte Carlo simulation using the Dartmouth Stellar Evolution Program. These isochrones take into consideration the uncertainty introduced by the choice of stellar evolution parameters. We fit isochrones with three detached …
RR Lyrae Stars Belonging to the Candidate Globular Cluster Patchick 99
Clarkson, William I.; Rich, R. Michael; Kunder, Andrea +16 more
Patchick 99 is a candidate globular cluster located in the direction of the Galactic bulge, with a proper motion almost identical to the field and extreme field star contamination. A recent analysis suggests it is a low-luminosity globular cluster with a population of RR Lyrae stars. We present new spectra of stars in and around Patchick 99, targe…
On the Determining Physical Factor of Jet-related Coronal Mass Ejections' Morphology in the High Corona
Shen, Yuandeng; Duan, Yadan; Tang, Zehao +2 more
A solar jet can often cause coronal mass ejections (CMEs) with different morphologies in the high corona, for example, jet-like CMEs, bubble-like CMEs, and so-called twin CMEs that include a pair of simultaneous jet-like and bubble-like CMEs. However, what determines the morphology of a jet-related CME is still an open question. Using high spatiot…
On the Origin of Fast-rotating Stars. I. Photometric Calibration and Results of AO-assisted BVRI+Hα Imaging of NGC 330 with SAMI/SOAR
Navarete, Felipe; Ticiani dos Santos, Pedro; Carciofi, Alex Cavaliéri +1 more
Hα emission is a clear indicator of circumstellar activity in Be stars, historically employed to assess the classical Be star (CBe) population in young open clusters (YOCs). The YOC NGC 330 in the Small Magellanic Cloud exhibits a large known fraction of CBe stars and was selected for a pilot study to establish a comprehensive methodology for iden…
Pulsed Iron Line Emission from the First Galactic Ultraluminous X-Ray Pulsar Swift J0243.6+6124
Zhang, S.; Tao, L.; Zhang, S. N. +14 more
We report the phase-resolved spectral results of the first Galactic pulsating ultraluminous X-ray source (PULX) Swift J0243.6+6124, modeling its 2017–2018 outburst peak using data collected by the Hard X-ray Modulation Telescope (Insight-HXMT). The broad energy coverage of Insight-HXMT allows us to obtain a more accurate spectral continuum to redu…
Global Impact of Emerging Internetwork Fields on the Low Solar Atmosphere
Gošić, M.; De Pontieu, B.; Sainz Dalda, A.
Small-scale, newly emerging internetwork (IN) magnetic fields are considered a viable source of energy and mass for the solar chromosphere and possibly the corona. Multiple studies show that single events of flux emergence can indeed locally heat the low solar atmosphere through interactions of the upward propagating magnetic loops and the preexis…