Search Publications
Multiwavelength observation of 1A 0535+262=HD 245770 from 2010 to 2021
Liu, Wei; Yan, Jingzhi; Xiao, Guangcheng +3 more
Context. 1A 0535+262 is a high-mass X-ray binary that went into a giant X-ray outburst in 2020. During this event, the X-ray luminosity reached the highest value measured over the last 30 years.
Aims: Our aim is to study the long-term variability of 1A 0535+262 before and after the 2020 major X-ray outburst and to uncover the mechanism that l…
Runaway O and Be stars found using Gaia DR3, new stellar bow shocks and search for binaries
Paredes, J. M.; Ribó, M.; Benaglia, P. +1 more
A relevant fraction of massive stars are runaways, moving with a significant peculiar velocity with respect to their environment. Kicks from supernova explosions or the dynamical ejection of stars from clusters can account for the runaway genesis. We have used Gaia DR3 data to study the velocity distribution of massive O and Be stars from the GOSC…
The Gaia ultracool dwarf sample-IV. GTC/OSIRIS optical spectra of Gaia late-M and L dwarfs
Caballero, J. A.; Montes, D.; Sarro, L. M. +20 more
As part of our comprehensive, ongoing characterization of the low-mass end of the main sequence in the Solar neighbourhood, we used the OSIRIS instrument at the 10.4 m Gran Telescopio Canarias to acquire low- and mid-resolution (R
Search for protostellar jets with UWISH2 in the molecular cloud complexes Vulpecula and IRDC G53.2
Tej, Anandmayee; Froebrich, Dirk; Samal, Manash +1 more
Jets and outflows are the early signposts of stellar birth. Using the UKIRT Wide Field Infrared Survey for H2 (UWISH2) at 2.12 µm, 127 outflows are identified in molecular cloud complexes Vulpecula OB1 and IRDC G53.2 covering 12 square degrees of the Galactic plane. Using multiwavelength data sets, from 1.2 to 70 µm, 79 youn…
Evidence of a sub-solar star in a microlensing event toward the LMC
Nucita, A. A.; De Paolis, F.; Franco, A. +1 more
Gravitational microlensing is known to be an impressive tool for searching dark, small, and compact objects that are missed by the usual astronomical observations. In this paper, by analysing multiple images acquired by DECam, we present the detection and a complete description of the microlensing event LMC J05074558-65574990 which is most likely …
Comparison of the Chemical Compositions between the Bright and Faint Red Clumps for the Metal-poor and Metal-rich Populations in the Milky Way Bulge
Lee, Young-Wook; Hong, Seungsoo; Lim, Dongwook
We examined the double red clump (RC) observed in the Galactic bulge, interpreted as a difference in distance ("X-shaped bulge scenario") or in chemical composition ("multiple population scenario"). To verify chemical differences between the RC groups, we performed low-resolution spectroscopy for RC and red giant branch (RGB) stars using Gemini-So…
Planet Hunters NGTS: New Planet Candidates from a Citizen Science Search of the Next Generation Transit Survey Public Data
Wheatley, Peter J.; Bayliss, Daniel; Schwamb, Megan E. +36 more
We present the results from the first two years of the Planet Hunters Next Generation Transit Survey (NGTS) citizen science project, which searches for transiting planet candidates in data from the NGTS by enlisting the help of members of the general public. Over 8000 registered volunteers reviewed 138,198 light curves from the NGTS Public Data Re…
The infalling elliptical galaxy M89: the chemical composition of the AGN disturbed hot atmosphere
Werner, Norbert; Mernier, François; Ercan, E. Nihal +4 more
The chemical enrichment of X-ray-emitting hot atmospheres has hitherto been primarily studied in galaxy clusters. These studies revealed relative abundances of heavy elements that are remarkably similar to Solar. Here, we present measurements of the metal content of M89 (NGC 4552), an elliptical galaxy infalling into the Virgo cluster with a ~10 k…
Characterisation of the X-ray point source variability in the eROSITA south ecliptic pole field
Salvato, M.; Buchner, J.; Nandra, K. +11 more
Aims: During the Spectrum Roentgen Gamma (SRG)/eROSITA all-sky surveys, X-ray sources close to the South Ecliptic Pole (SEP) are observed almost every 4 h. We aim to identify the sources exhibiting the most significant long-term X-ray variability within 3° of the SEP in the first three surveys, and investigate their properties.
Methods: …
Data-driven Stellar Intrinsic Colors and Dust Reddenings for Spectrophotometric Data: From the Blue-edge Method to a Machine Learning Approach
Ren, Yi; Wang, Shu; Jiang, Biwei +4 more
Intrinsic colors (ICs) of stars are essential for studies on both stellar physics and dust reddening. In this work, we developed an XGBoost model to predict ICs with the atmospheric parameters T eff,