Search Publications
Discovery and Timing of Millisecond Pulsars in the Globular Cluster M5 with FAST and Arecibo
Fu, Xiaoting; Tsai, Chao-Wei; Cadelano, Mario +29 more
We report on a comprehensive multiwavelength study of the pulsars in the globular cluster (GC) M5, including the discovery of M5G, a new compact noneclipsing "black widow" pulsar. Thanks to the analysis of 34 yr of radio data taken with the Five-hundred-meter Aperture Spherical radio Telescope and Arecibo telescopes, we obtained new phase-connecte…
Identifying 46 New Open Cluster Candidates in Gaia EDR3 Using a Hybrid pyUPMASK and Random Forest Method
Wang, Feng; Li, Zhongmu; Chi, Huanbin +1 more
Open clusters (OCs) are regarded as tracers to understand stellar evolution theory and validate stellar models. In this study, we presented a robust approach to identifying OCs. A hybrid method consisting of pyUPMASK and the random forest (RF) algorithm is first used to remove field stars and determine more reliable members. An identification mode…
Large-scale Spatial Cross-calibration of Hinode/SOT-SP and SDO/HMI
Liu, Yang; Antiochos, Spiro K.; Leka, K. D. +7 more
We investigate the cross-calibration of the Hinode/Solar Optical Telescope-Spectro-Polarimeter (SOT-SP) and Solar Dynamics Observatory/Helioseismic and Magnetic Imager (SDO/HMI) instrument metadata, specifically the correspondence of the scaling and pointing information. Accurate calibration of these data sets gives the correspondence needed by in…
Catalog of the Galactic Population of X-Ray Pulsars in High-mass X-Ray Binary Systems
Kim, Vitaliy; Izmailova, Ildana; Aimuratov, Yerlan
A catalog of the Galactic population of X-ray pulsars in high-mass X-ray binary (HMXB) systems is presented. It contains information about 82 confirmed sources: 18 persistent and 64 transient pulsars. Their basic parameters include spin period, spin evolution with global and local spin-up/spin-down and duration, orbital period, X-ray luminosity, m…
ABYSS. I. Targeting Strategy for the APOGEE and BOSS Young Star Survey in SDSS-V
Kounkel, Marina; Stringfellow, Guy; Rojas-Ayala, Bárbara +15 more
The fifth iteration of the Sloan Digital Sky Survey is set to obtain optical and near-infrared spectra of ~5 million stars of all ages and masses throughout the Milky Way. As a part of these efforts, APOGEE and BOSS Young Star Survey (ABYSS) will observe ~105 stars with ages <30 Myr that have been selected using a set of homogeneous …
Unbiased CLEAN for STIX in Solar Orbiter
Volpara, Anna; Massa, Paolo; Piana, Michele +3 more
CLEAN is an iterative deconvolution method for radio and hard-X-ray solar imaging. In a specific step of its pipeline, CLEAN requires the convolution between an idealized version of the instrumental point-spread function (PSF), and a map collecting point sources located at positions from where most of the flaring radiation is emitted. This step ha…
Prediction of the Transit Time of Coronal Mass Ejections with an Ensemble Machine-learning Method
Yang, Y.; Feng, X. S.; Chen, P. F. +2 more
Coronal mass ejections (CMEs), a kind of violent solar eruptive activity, can exert a significant impact on space weather. When arriving at the Earth, they interact with the geomagnetic field, which can boost the energy supply to the geomagnetic field and may further result in geomagnetic storms, thus having potentially catastrophic effects on hum…
The GW Vir Instability Strip in Light of New Observations of PG 1159 Stars: Discovery of Pulsations in the Central Star of A72 and Variability of RX J0122.9-7521
Jones, David; Karjalainen, Marie; Caldwell, John A. R. +9 more
We present the results of new time-series photometric observations of 29 pre-white dwarf stars of PG 1159 spectral type, carried out in the years 2014-2022. For the majority of stars, a median noise level in Fourier amplitude spectra of 0.5-1.0 mmag was achieved. This allowed the detection of pulsations in the central star of planetary nebula A72 …
A Catalog of Young Stellar Objects from the LAMOST and ZTF Surveys
Zhang, Jingyi; Zhang, Yanxia; Kang, Zihan +2 more
As astronomical data sets become too large for traditional analysis approaches, more machine-learning algorithms are employed in astronomy. A wealth of light variation data have been accumulated, which provide rich samples for astronomers to study variable stars. Facing the challenge of big data, this article takes the classification of variable a…
The Classification of Galaxy Morphology in the H Band of the COSMOS-DASH Field: A Combination-based Machine-learning Clustering Model
Fang, Guanwen; Lin, Zesen; Kong, Xu +6 more
By applying our previously developed two-step scheme for galaxy morphology classification, we present a catalog of galaxy morphology for H-band-selected massive galaxies in the COSMOS-DASH field, which includes 17,292 galaxies with stellar mass M ⋆ > 1010 M ⊙ at 0.5 < z < 2.5. The classification scheme is …