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Extremely Broad Lyα Line Emission from the Molecular Intragroup Medium in Stephan's Quintet: Evidence for a Turbulent Cascade in a Highly Clumpy Multiphase Medium?
DOI: 10.3847/1538-4357/ac313f Bibcode: 2022ApJ...925...63G

Shull, J. M.; Boulanger, F.; Falgarone, E. +8 more

We present Hubble Space Telescope Cosmic Origin Spectrograph (COS) UV line spectroscopy and integral-field unit (IFU) observations of the intragroup medium in Stephan's Quintet (SQ). SQ hosts a 30 kpc long shocked ridge triggered by a galaxy collision at a relative velocity of 1000 km s-1, where large amounts of molecular gas coexist wi…

2022 The Astrophysical Journal
eHST 8
Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence
DOI: 10.3389/fspas.2022.1040945 Bibcode: 2022FrASS...940945L

Polito, Vanessa; Yu, Sijie; De Pontieu, Bart +2 more

We report on observations of highly-varying Si IV 1402.77 Å line profiles observed with the Interface Region Imaging Spectrograph (IRIS) during the M-class flare from 2022 January 18 at an unprecedented 0.8 s cadence. Moment analysis of this line observed in flare ribbon kernels showed that the intensity, Doppler velocity, and non-thermal broadeni…

2022 Frontiers in Astronomy and Space Sciences
IRIS 8
Radial Velocity Survey for Planets around Young stars (RVSPY). Target characterisation and high-cadence survey
DOI: 10.1051/0004-6361/202244213 Bibcode: 2022A&A...667A..63Z

Trifonov, Trifon; Henning, Thomas; Reffert, Sabine +15 more

Context. The occurrence rate and period distribution of (giant) planets around young stars is still not as well constrained as for older main-sequence stars. This is mostly due to the intrinsic activity-related complications and the avoidance of young stars in many large planet search programmes. Yet, dynamical restructuring processes in planetary…

2022 Astronomy and Astrophysics
Gaia 8
Multiwavelength Observations by XSM, Hinode, and SDO of an Active Region. Chemical Abundances and Temperatures
DOI: 10.3847/1538-4357/ac7a9a Bibcode: 2022ApJ...934..159D

Mason, H. E.; Del Zanna, G.; Janardhan, P. +7 more

We have reviewed the first year of observations of the Solar X-ray Monitor (XSM) on board Chandrayaan-2 and the available multiwavelength observations to complement the XSM data, focusing on the Solar Dynamics Observatory AIA and Hinode XRT and EIS observations. XSM has provided disk-integrated solar spectra in the 1-15 keV energy range, observing…

2022 The Astrophysical Journal
Hinode 8
Variations in Vertical CO/CO2 Profiles in the Martian Mesosphere and Lower Thermosphere Measured by the ExoMars TGO/NOMAD: Implications of Variations in Eddy Diffusion Coefficient
DOI: 10.1029/2022GL098485 Bibcode: 2022GeoRL..4998485Y

Vandaele, Ann Carine; Modak, Ashimananda; Brines, Adrian +19 more

Using the Nadir and Occultation for MArs Discovery instrument aboard Trace Gas Orbiter, we derived the CO/CO2 profiles between 75 and 105 km altitude with the equivalent width technique. The derived CO/CO2 profiles showed significant seasonal variations in the southern hemisphere with decreases near perihelion and increases n…

2022 Geophysical Research Letters
ExoMars-16 8
System parameters of three short-period cataclysmic variable stars
DOI: 10.1093/mnras/stab3260 Bibcode: 2022MNRAS.509.5086W

Dhillon, V. S.; Breedt, E.; Marsh, T. R. +9 more

Using photometric ULTRACAM observations of three new short-period cataclysmic variables (CVs), we model the primary eclipse light curves to extract the orbital separation, masses, and radii of their component stars. We find donor masses of $0.060\pm 0.008\, {\rm M_\odot }$, $0.042\pm 0.001\, {\rm M_\odot }$, and $0.042\pm 0.004\, {\rm M_\odot }$, …

2022 Monthly Notices of the Royal Astronomical Society
Gaia 8
A Generative Model for Quasar Spectra
DOI: 10.3847/1538-4357/ac8ead Bibcode: 2022ApJ...938...17E

Hogg, David W.; Foreman-Mackey, Daniel; Schindler, Jan-Torge +3 more

We build a multi-output generative model for quasar spectra and the properties of their black hole engines, based on a Gaussian process latent-variable model. This model treats every quasar as a vector of latent properties such that the spectrum and all physical properties of the quasar are associated with non-linear functions of those latent para…

2022 The Astrophysical Journal
eHST 8
K2-79b and K2-222b: Mass Measurements of Two Small Exoplanets with Periods beyond 10 days that Overlap with Periodic Magnetic Activity Signals
DOI: 10.3847/1538-3881/ac3141 Bibcode: 2022AJ....163...41N

Vanderburg, Andrew; López-Morales, Mercedes; Bieryla, Allyson +28 more

We present mass and radius measurements of K2-79b and K2-222b, two transiting exoplanets orbiting active G-type stars observed with HARPS-N and K2. Their respective 10.99 day and 15.39 day orbital periods fall near periods of signals induced by stellar magnetic activity. The two signals might therefore interfere and lead to an inaccurate estimate …

2022 The Astronomical Journal
Gaia 8
Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS - IV. Discovery of two new GW Vir stars: TIC 0403800675 and TIC 1989122424
DOI: 10.1093/mnras/stac1027 Bibcode: 2022MNRAS.513.2285U

Kepler, S. O.; Córsico, Alejandro H.; Uzundag, Murat +4 more

We present two new GW Vir-type pulsating white dwarf stars, TIC 0403800675 (WD J115727.68-280349.64) and TIC 1989122424 (WD J211738.38-552801.18) discovered in the Transiting Exoplanet Survey Satellite (TESS) photometric data. For both stars, the TESS light curves reveal the presence of oscillations with periods in a narrow range between 400 and 4…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 8
Fast time optical variability in Be/X-ray binaries. Pulsation and rotation
DOI: 10.1051/0004-6361/202243664 Bibcode: 2022A&A...667A..18R

Reig, P.; Fabregat, J.

Context. Classical Be stars, regardless of spectral subtype, display multi-periodic light modulations in the frequency range 0.1-12 c d−1 when observed with a high cadence and a long duration. This behavior is attributed to non-radial pulsations and/or the rotation of the Be star. A similar study on the optical counterparts to Be/X-ray …

2022 Astronomy and Astrophysics
Gaia 8