Search Publications
XMM-Newton Detection of X-Ray Emission from the Metal-polluted White Dwarf G 29-38
Chu, Y. -H.; Estrada-Dorado, S.; Guerrero, M. A. +3 more
A recent analysis of Chandra X-ray data of the metal-polluted white dwarf G 29-38 has revealed X-ray emission that can be attributed to the accretion of debris from a planetary body. In the light of this detection we revisit here archival XMM-Newton observations of G 29-38 from which only an upper limit was derived in the past due to the presence …
Spectra of V1405 Cas at the Very Beginning Indicate a Low-mass ONeMg White Dwarf Progenitor
Maehara, Hiroyuki; Nogami, Daisaku; Yamanaka, Masayuki +9 more
The lowest possible mass of ONeMg white dwarfs (WDs) has not been clarified despite its importance in the formation and evolution of WDs. We tackle this issue by studying the properties of V1405 Cas (Nova Cassiopeiae 2021), which is an outlier given a combination of its very slow light-curve evolution and the recently reported neon-nova identifica…
On the Migration Origin of the Hercules Moving Group with GAIA, LAMOST, APOGEE, and GALAH Surveys
Wu, Yaqian; Zhao, Jingkun; Yoon, Suk-Jin +3 more
Using Gaia DR3 data and the wavelet transformation technique, we study the substructures of the Hercules moving group (HMG): Hercules 1 (H1) and Hercules 2 (H2). Spectroscopic survey data from LAMOST, APOGEE, and GALAH are used to obtain metallicities and ages of stars belonging to the HMG. Our analysis leads to several key findings as follows: (a…
An Extremely Massive White Dwarf Escaped from the Hyades Star Cluster
El-Badry, Kareem; Rodriguez, Antonio C.; van Roestel, Jan +5 more
We searched the Gaia DR3 database for ultramassive white dwarfs with kinematics consistent with having escaped the nearby Hyades open cluster, identifying three such candidates. Two of these candidates have masses estimated from Gaia photometry of approximately 1.1 solar masses; their status as products of single-stellar evolution that have escape…
The Differential Assembly History of the Centers and Outskirts of Main-sequence Galaxies at z 2.3
Giavalisco, Mauro; Ji, Zhiyuan; Cutler, Sam E. +1 more
We present a study of spatially resolved star formation histories (SFHs) for 60 z ~ 2.3 main-sequence, star-forming galaxies selected from the MOSDEF spectroscopic survey in the GOODS-N field, with median stellar mass $\mathrm{log}({M}_{\star }/{M}_{\odot })$ = 9.75 and spanning the range $8.6\lt \mathrm{log}({M}_{\star }/{M}_{\odot })\lt 11.5$ . …
Fast Reconstruction of 3D Density Distribution around the Sun Based on the MAS by Deep Learning
Moon, Yong-Jae; Rahman, Sumiaya; Park, Eunsu +5 more
This study is the first attempt to generate a three-dimensional (3D) coronal electron density distribution based on the pix2pixHD model, whose computing time is much shorter than that of the magnetohydrodynamic (MHD) simulation. For this, we consider photospheric solar magnetic fields as input, and electron density distribution simulated with the …
Electrostatic Solitary Waves in the Venusian Ionosphere Pervaded by the Solar Wind: A Theoretical Perspective
Lakhina, G. S.; Kamalam, T.; Singh, S. V. +3 more
Electrostatic solitary waves (ESWs) in the Venusian ionosphere that are impinged by the solar wind are investigated using a homogeneous, collisionless, and magnetized multicomponent plasma consisting of Venusian H+ and O+ ions, Maxwellian Venusian electrons and streaming solar wind protons, and suprathermal electrons followin…
Halfway to the Peak: Spatially Resolved Star Formation and Kinematics in a z = 0.54 Dusty Galaxy with JWST/MIRI
Veilleux, Sylvain; Ogle, Patrick; Alberts, Stacey +16 more
We present JWST Mid-InfraRed Instrument/Medium-Resolution Spectrometer (MIRI/MRS) observations of an infrared luminous disk galaxy, FLS1, at z ~ 0.54. With a lookback time of 5 Gyr, FLS1 is chronologically at the midpoint between the peak epoch of star formation and the present day. The MRS data provide maps of the atomic fine structure lines [Ar …
Separated Twins or Just Siblings? A Multiplanet System around an M Dwarf Including a Cool Sub-Neptune
Quinn, Samuel N.; Stassun, Keivan G.; Zhou, George +27 more
We report the discovery of two TESS sub-Neptunes orbiting the early M dwarf TOI-904 (TIC 261257684). Both exoplanets, TOI-904 b and c, were initially observed in TESS Sector 12 with twin sizes of ${2.426}_{-0.157}^{+0.163}$ and ${2.167}_{-0.118}^{+0.130}$ R ⊕, respectively. Through observations in five additional sectors in the TESS pri…
Cosmic-CoNN: A Cosmic-Ray Detection Deep-learning Framework, Data Set, and Toolkit
Howell, D. Andrew; McCully, Curtis; Xu, Chengyuan +2 more
Rejecting cosmic rays (CRs) is essential for the scientific interpretation of CCD-captured data, but detecting CRs in single-exposure images has remained challenging. Conventional CR detectors require experimental parameter tuning for different instruments, and recent deep-learning methods only produce instrument-specific models that suffer from p…