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Hydrodynamic Atmospheric Escape in HD 189733 b: Signatures of Carbon and Hydrogen Measured with the Hubble Space Telescope
DOI: 10.3847/1538-3881/ace445 Bibcode: 2023AJ....166...89D

Mikal-Evans, Thomas; Sing, David K.; López-Morales, Mercedes +10 more

One of the most well-studied exoplanets to date, HD 189733 b, stands out as an archetypal hot Jupiter with many observations and theoretical models aimed at characterizing its atmosphere, interior, host star, and environment. We report here on the results of an extensive campaign to observe atmospheric escape signatures in HD 189733 b using the Hu…

2023 The Astronomical Journal
eHST 8
The HH 24 Complex: Jets, Multiple Star Formation, and Orphaned Protostars
DOI: 10.3847/1538-3881/acadd4 Bibcode: 2023AJ....165..209R

Yen, Hsi-Wei; Comerón, F.; Bally, J. +9 more

The HH 24 complex harbors five collimated jets emanating from a small protostellar multiple system. We have carried out a multiwavelength study of the jets, their driving sources, and the cloud core hosting the embedded stellar system, based on data from the Hubble Space Telescope, Gemini, Subaru, Apache Point Observatory 3.5 m, Karl G. Jansky Ver…

2023 The Astronomical Journal
Gaia Herschel eHST 8
Coronal X-Ray Emission from Nearby, Low-mass, Exoplanet Host Stars Observed by the MUSCLES and Mega-MUSCLES HST Treasury Survey Projects
DOI: 10.3847/1538-3881/acc38a Bibcode: 2023AJ....165..195B

Loyd, R. O. Parke; Kowalski, Adam F.; Brown, Alexander +8 more

The high-energy X-ray and ultraviolet (UV) radiation fields of exoplanet host stars play a crucial role in controlling the atmospheric conditions and the potential habitability of exoplanets. Major surveys of the X-ray/UV emissions from late-type (K and M spectral types) exoplanet hosts have been conducted by the Measurements of the Ultraviolet Sp…

2023 The Astronomical Journal
Gaia XMM-Newton eHST 8
Resolved SPLASH Chemodynamics in Andromeda's PHAT Stellar Halo and Disk: On the Nature of the Inner Halo along the Major Axis
DOI: 10.3847/1538-3881/aca9cd Bibcode: 2023AJ....165...75E

Williams, Benjamin F.; Gilbert, Karoline M.; Guhathakurta, Puragra +5 more

Stellar kinematics and metallicity are key to exploring formation scenarios for galactic disks and halos. In this work, we characterized the relationship between kinematics and photometric metallicity along the line of sight to M31's disk. We combined optical Hubble Space Telescope/Advanced Camera for Surveys photometry, from the Panchromatic Hubb…

2023 The Astronomical Journal
ExoMars-16 eHST 7
Spectroscopically Identified Cataclysmic Variables from the LAMOST Survey. II. Period Estimates
DOI: 10.3847/1538-3881/aca906 Bibcode: 2023AJ....165..148H

Luo, A. -Li; Hou, Wen; Bai, Zhong-Rui +2 more

We examine a sample of 340 cataclysmic variables (CVs) from the latest data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey, along with 18 objects that are newly classified as CVs. In this paper, we focus on investigating the photometric behaviors of these CVs using data from time-domain surveys. The orbita…

2023 The Astronomical Journal
Gaia 7
ELM of ELM-WD: An Extremely-low-mass Hot Star Discovered in LAMOST Survey
DOI: 10.3847/1538-3881/acaf07 Bibcode: 2023AJ....165..119Y

Chen, Xuefei; Li, Zhenwei; Zhang, Haotong +7 more

The extremely-low-mass white dwarfs (ELM WDs) and pre-ELM WDs are helium-core white dwarfs with mass <~ 0.3M . Evolution simulations show that a lower mass limit for ELM WDs exists at ≈0.14M and no ELM WD is proposed by observation to be less massive than that. Here we report the discovery of a binary system, LAMOST J22…

2023 The Astronomical Journal
Gaia INTEGRAL 7
FUMES. III. Ultraviolet and Optical Variability of M-dwarf Chromospheres
DOI: 10.3847/1538-3881/ac9b49 Bibcode: 2023AJ....165...12D

France, Kevin; Youngblood, Allison; Pineda, J. Sebastian +2 more

We obtained ultraviolet and optical spectra for nine M dwarfs across a range of rotation periods to determine whether they showed stochastic intrinsic variability distinguishable from flares. The ultraviolet spectra were observed during the Far Ultraviolet M-dwarf Evolution Survey Hubble Space Telescope program using the Space Telescope Imaging Sp…

2023 The Astronomical Journal
eHST 7
Magnetic Fields in the Horsehead Nebula
DOI: 10.3847/1538-3881/acc460 Bibcode: 2023AJ....165..198H

Pattle, Kate; Hwang, Jihye; Kim, Jongsoo +2 more

We present the first polarized dust emission measurements of the Horsehead Nebula, obtained using the POL-2 polarimeter on the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera on the James Clerk Maxwell Telescope. The Horsehead Nebula contains two submillimeter sources: a photodissociation region (PDR; SMM1) and a starless core (SMM2).…

2023 The Astronomical Journal
eHST 7
The Great Dimming of the Hypergiant Star RW Cephei: CHARA Array Images and Spectral Analysis
DOI: 10.3847/1538-3881/ace59d Bibcode: 2023AJ....166...78A

Gies, Douglas R.; Monnier, John D.; Schaefer, Gail H. +15 more

The cool hypergiant star RW Cephei is currently in a deep photometric minimum that began several years ago. This event bears a strong similarity to the Great Dimming of the red supergiant Betelgeuse that occurred in 2019-2020. We present the first resolved images of RW Cephei that we obtained with the CHARA Array interferometer. The angular diamet…

2023 The Astronomical Journal
Gaia 7
Planetary Orbit Eccentricity Trends (POET). I. The Eccentricity-Metallicity Trend for Small Planets Revealed by the LAMOST-Gaia-Kepler Sample
DOI: 10.3847/1538-3881/acb533 Bibcode: 2023AJ....165..125A

Zhou, Ji-Lin; Xie, Ji-Wei; Dai, Yuan-Zhe +1 more

Orbital eccentricity is one of the basic planetary properties, whose distribution may shed light on the history of planet formation and evolution. Here, in a series of works on Planetary Orbit Eccentricity Trends (dubbed POET), we study the distribution of planetary eccentricities and their dependence on stellar/planetary properties. In this paper…

2023 The Astronomical Journal
Gaia 7