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A cool, magnetic white dwarf accreting planetary debris
DOI: 10.1093/mnras/stad3370 Bibcode: 2024MNRAS.527.3122V

Vennes, Stéphane; Weinberger, Alycia J.; Zuckerman, B. +3 more

We present an analysis of spectroscopic data of the cool, highly magnetic, and polluted white dwarf 2MASS J0916-4215. The atmosphere of the white dwarf is dominated by hydrogen, but numerous spectral lines of magnesium, calcium, titanium, chromium, iron, and strontium, along with Li I, Na I, Al I, and K I lines, are found in the incomplete Paschen…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 8
Measurements of the Low-acceleration Gravitational Anomaly from the Normalized Velocity Profile of Gaia Wide Binary Stars and Statistical Testing of Newtonian and Milgromian Theories
DOI: 10.3847/1538-4357/ad61e9 Bibcode: 2024ApJ...972..186C

Chae, Kyu-Hyun

Low-acceleration gravitational anomaly is investigated with a new method of exploiting the normalized velocity profile vv

2024 The Astrophysical Journal
Gaia 8
Exploring the ultra-hot Jupiter WASP-178b. Constraints on atmospheric chemistry and dynamics from a joint retrieval of VLT/CRIRES+ and space photometric data
DOI: 10.1051/0004-6361/202450064 Bibcode: 2024A&A...688A.206C

Nagel, E.; Czesla, S.; Nortmann, L. +14 more

Despite recent progress in the spectroscopic characterization of individual exoplanets, the atmospheres of key ultra-hot Jupiters (UHJs) still lack comprehensive investigations. These include WASP-178b, one of the most irradiated UHJs known to date. We observed the dayside emission signal of this planet with CRIRES+ in the spectral K ba…

2024 Astronomy and Astrophysics
CHEOPS 8
Detection of pulsed X-ray emission from the isolated neutron star candidate eRASSU J131716.9-402647
DOI: 10.1051/0004-6361/202347967 Bibcode: 2024A&A...683A.164K

Haberl, F.; Pires, A. M.; Schwope, A. D. +1 more

The X-ray source eRASSU J131716.9-402647 was recently identified from observations with Spectrum Roentgen Gamma (SRG)/eROSITA as a promising X-ray dim isolated neutron star (XDINS) candidate on the premise of a soft energy distribution, absence of catalogued counterparts, and a high X-ray-to-optical flux ratio. Here, we report t…

2024 Astronomy and Astrophysics
XMM-Newton 8
Unveiling the white dwarf in J191213.72 - 441045.1 through ultraviolet observations
DOI: 10.1093/mnras/stad3442 Bibcode: 2024MNRAS.527.3826P

Lyutikov, Maxim; Barkov, Maxim; Pelisoli, Ingrid +7 more

J191213.72 - 441045.1 is a binary system composed of a white dwarf and an M-dwarf in a 4.03-h orbit. It shows emission in radio, optical, and X-ray, all modulated at the white dwarf spin period of 5.3 min, as well as various orbital sideband frequencies. Like in the prototype of the class of radio-pulsing white dwarfs, AR Scorpii, the observed pul…

2024 Monthly Notices of the Royal Astronomical Society
Gaia eHST 8
Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star HIP 39017
DOI: 10.3847/1538-3881/ad3077 Bibcode: 2024AJ....167..205T

Salama, Maïssa; Currie, Thayne; Lewis, Briley L. +23 more

We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, γ Doradus (γ Dor)-type variable star HIP 39017 (HD 65526). The companion's SCExAO/CHARIS JHK (1.1–2.4 µm) spectrum and Keck/NIRC2 $L^{\prime} $ photometry indicate that it is an L/T transition object. A comparison of the…

2024 The Astronomical Journal
Gaia Hipparcos 8
PEARLS: A Potentially Isolated Quiescent Dwarf Galaxy with a Tip of the Red Giant Branch Distance of 30 Mpc
DOI: 10.3847/2041-8213/ad1b56 Bibcode: 2024ApJ...961L..37C

Grogin, Norman A.; Holwerda, Benne W.; Koekemoer, Anton M. +25 more

A wealth of observations have long suggested that the vast majority of isolated classical dwarf galaxies (M * = 107–109 M ) are currently star forming. However, recent observations of the large abundance of "ultra-diffuse galaxies" beyond the reach of previous large spectroscopic surveys suggest that ou…

2024 The Astrophysical Journal
JWST 8
Strong He I Emission Lines in High N/O Galaxies at z ∼ 6 Identified in JWST Spectra: High He/H Abundance Ratios or High Electron Densities?
DOI: 10.3847/1538-4357/ad72ec Bibcode: 2024ApJ...974..266Y

Ono, Yoshiaki; Ouchi, Masami; Harikane, Yuichi +14 more

We present He I/Hβ flux and He/H abundance ratios in three James Webb Space Telescope galaxies with significant constraints on N/O abundance ratios, GS-NDG-9422, RXCJ2248-ID, and GLASS150008 at z ∼ 6 mostly with the spectroscopic coverage from He I λ4471 and He II λ4686 to He I λ7065, and comparing with 68 local dwarf galaxies. We find that these …

2024 The Astrophysical Journal
JWST 8
Masses, revised radii, and a third planet candidate in the 'Inverted' planetary system around TOI-1266
DOI: 10.1093/mnras/stad3450 Bibcode: 2024MNRAS.527.5464C

Knutson, Heather; Vanderburg, Andrew; López-Morales, Mercedes +40 more

Is the population of close-in planets orbiting M dwarfs sculpted by thermally driven escape or is it a direct outcome of the planet formation process? A number of recent empirical results strongly suggest the latter. However, the unique architecture of the TOI-1266 system presents a challenge to models of planet formation and atmospheric escape gi…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 8
CatNorth: An Improved Gaia DR3 Quasar Candidate Catalog with Pan-STARRS1 and CatWISE
DOI: 10.3847/1538-4365/ad2ae6 Bibcode: 2024ApJS..271...54F

Feng, Xiaotong; Wolf, Christian; Bouwens, R. J. +17 more

A complete and pure sample of quasars with accurate redshifts is crucial for quasar studies and cosmology. In this paper, we present CatNorth, an improved Gaia Data Release 3 (Gaia DR3) quasar candidate catalog with more than 1.5 million sources in the 3π sky built with data from Gaia, Pan-STARRS1, and CatWISE2020. The XGBoost algorithm is used to…

2024 The Astrophysical Journal Supplement Series
Gaia 8