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The Panchromatic Hubble Andromeda Treasury. XXI. The Legacy Resolved Stellar Photometry Catalog
Bell, Eric F.; Dolphin, Andrew E.; Yanchulova Merica-Jones, Petia +14 more
We present the final legacy version of stellar photometry for the Panchromatic Hubble Andromeda Treasury (PHAT) survey. We have reprocessed all of the Hubble Space Telescope Wide Field Camera 3 and Advanced Camera for Surveys near-ultraviolet (F275W, F336W), optical (F475W, F814W), and near-infrared (F110W, F160W) imaging from the PHAT survey usin…
Formulating Mass-loss Rates for Sun-like Stars: A Hybrid Model Approach
Toriumi, Shin; Cranmer, Steven R.; Shoda, Munehito
We observe an enhanced stellar wind mass-loss rate from low-mass stars exhibiting higher X-ray flux. This trend, however, does not align with the Sun, where no evident correlation between X-ray flux and mass-loss rate is present. To reconcile these observations, we propose a hybrid model for the stellar wind from solar-type stars, incorporating bo…
Hemispheric distribution of coronal mass ejections from 1996 to 2020
Li, C.; Deng, L. H.; Zhang, X. J. +3 more
Solar magnetic structures are known to be asymmetrically distributed between the two hemispheres. To date, the hemispheric variations of the coronal mass ejections (CMEs) at different latitudes, in different cycles, and for different types (regular and specific events) are still unclear. From the list of white-light CMEs in the Coordinated Data An…
Kinematics of stellar substructures in the small magellanic cloud
de Grijs, Richard; Kacharov, Nikolay; Cioni, Maria-Rosa L. +6 more
We present a kinematic analysis of the Small Magellanic Cloud using 3700 spectra extracted from the European Southern Observatory archive. We used data from Gaia and near-infrared photometry to select stellar populations and discard Galactic foreground stars. The sample includes main-sequence red giant branch and red clump stars, observed with Fib…
Retrieval of Martian Atmospheric CO Vertical Profiles From NOMAD Observations During the First Year of TGO Operations
Modak, Ashimananda; López-Valverde, Miguel Angel; Brines, Adrian +19 more
We present CO density profiles up to about 100 km in the Martian atmosphere obtained for the first time from retrievals of solar occultation measurements by the Nadir and Occultation for Mars Discovery (NOMAD) onboard ExoMars Trace Gas Orbiter (TGO). CO is an important trace gas on Mars, as it is controlled by CO2 photolysis, chemical r…
PIC Simulations of Overstretched Ion-Scale Current Sheets in the Magnetotail
Arnold, H.; Sitnov, M. I.
Onset of reconnection in the tail requires the current sheet thickness to be of the order of the ion thermal gyroradius or smaller. However, existing isotropic plasma models cannot explain the formation of such thin sheets at distances where the X-lines are typically observed. Here we reproduce such thin and long sheets in particle-in-cell simulat…
Multi-epoch hard X-ray view of Compton-thick AGN Circinus Galaxy
Gandhi, Poshak; Ricci, Claudio; Kayal, Abhijit +4 more
The circumnuclear material around active galactic nuclei (AGNs) is one of the essential components of the obscuration-based unification model. However, our understanding of the circumnuclear material in terms of its geometrical shape, structure, and its dependence on accretion rate is still debated. In this paper, we present the multi-epoch broad-…
An XMM-Newton View of the Symbiotic Stars HM Sge, NQ Gem, and PU Vul
Toalá, Jesús A.; Sabin, Laurence; Botello, Marissa K.
We present the analysis of archival XMM-Newton observations of the symbiotic stars HM Sge, NQ Gem, and PU Vul. The EPIC-pn spectra hint at the presence of emission lines, which are further confirmed in the first-order RGS spectra of the three sources. Spectral modeling of the EPIC-pn data discloses unprecedented characteristics; for instance, the …
Discovery and characterization of two Neptune-mass planets orbiting HD 212729 with TESS
Torres, Guillermo; Latham, David W.; Wheatley, Peter J. +33 more
We report the discovery of two exoplanets orbiting around HD 212729 (TOI 1052, TIC 317060587), a Teff = 6146 K star with V = 9.51 observed by TESS in Sectors 1 and 13. One exoplanet, TOI-1052b, is Neptune-mass and transits the star, and an additional planet TOI-1052c is observed in radial velocities but not seen to transit. We confirm t…
Further Evidence for the 9 s Pulsation in LS 5039 from NuSTAR and ASCA
Enoto, Teruaki; Makishima, Kazuo; Takahashi, Tadayuki +2 more
The present study aims to reinforce the evidence for the ~9 s pulsation in the gamma-ray binary LS 5039, derived from a Suzaku observation in 2007 and a NuSTAR observation in 2016. Through a reanalysis of the NuSTAR data incorporating the orbital Doppler correction, the 9.0538 s pulsation was confirmed successfully even in the 3-10 keV range, wher…