Search Publications
Identification of SRGt 062340.2-265751 as a bright, strongly variable, novalike cataclysmic variable
Maitra, Chandreyee; Wilms, Jörn; Buckley, David A. H. +10 more
We report the identification and follow-up of the transient SRGt 062340.2-265751 detected with both instruments on board the Spektrum-Roentgen-Gamma mission. Optical spectroscopy of the G = 12.5 counterpart firmly classifies the object as a novalike cataclysmic variable (CV) at a distance of 495 pc. A highly significant TESS period of 3.941 h, ten…
First detection of a magnetic field in low-luminosity B[e] stars. New scenarios for the nature and evolutionary stages of FS CMa stars
Manset, N.; Sestito, F.; Raj, A. +8 more
We report the first detection of the magnetic field in a star of FS CMa type, a subgroup of objects characterized by the B[e] phenomenon. The split of magnetically sensitive lines in IRAS 17449+2320 determines the magnetic field modulus of 6.2 ± 0.2 kG. Spectral lines and their variability reveal the presence of a B-type spectrum and a hot continu…
Unravelling UBC 274: A morphological, kinematical, and chemical analysis of a disrupting open cluster
Castro-Ginard, A.; Casamiquela, L.; Soubiran, C. +8 more
Context. Open clusters in the process of disruption help to understand the formation and evolution of the Galactic disk. The wealth and homogeneity of Gaia data have led to the discovery of several open clusters with signs of disruption. Detailed chemical information for these clusters is essential in order to study the timescales and interplay be…
SRG/eROSITA discovery of 164 s pulsations from the SMC Be/X-ray binary XMMU J010429.4-723136
Haberl, F.; Schwope, A.; Monageng, I. M. +5 more
Context. The Small Magellanic Cloud (SMC) hosts many known high-mass X-ray binaries (HMXBs), and all but one (SMC X-1) have a Be companion star. Through the calibration and verification phase of eROSITA on board the Spektrum-Roentgen-Gamma (SRG) spacecraft, the Be/X-ray binary XMMU J010429.4-723136 was in the field of view during observations of t…
Efficient dust radial drift around young intermediate-mass stars
Garufi, Antonio; Pinilla, Paola; Gárate, Matías
The radial velocities and direct imaging observations of exoplanets have suggested that the frequency of giant planets may decrease for intermediate-mass stars (2.5 − 8 M⊙). The key mechanism that could hinder their formation remains unclear. From a theoretical point of view, planet formation around intermediate-mass stars may take plac…
Zero-phase angle asteroid taxonomy classification using unsupervised machine learning algorithms
Alvarez-Candal, A.; Duffard, R.; Colazo, M.
Context. We are in an era of large catalogs and, thus, statistical analysis tools for large data sets, such as machine learning, play a fundamental role. One example of such a survey is the Sloan Moving Object Catalog (MOC), which lists the astrometric and photometric information of all moving objects captured by the Sloan field of view. One great…
Absolute colors and phase coefficients of asteroids
Alvarez-Candal, A.; Colazo, M.; Jimenez Corral, S.
Context. We use the phase curves of small bodies to measure absolute magnitudes and, together with complementary theoretical and laboratory results, to understand the micro- and macroscopic properties of their surfaces. Although we can observe asteroids up to phase angles of about 30 deg, the range of phase angles covered by outer Solar System obj…
Analysis of high-resolution FEROS spectroscopy for a sample of variable B-type stars assembled from TESS photometry
Xiang, Maosheng; Rix, Hans-Walter; Bowman, Dominic M. +8 more
Context. Spectroscopic data are necessary to break degeneracies in the asteroseismic modelling of the interior structure in high- and intermediate-mass stars. With the TESS mission, the number of bright intermediate-mass B-type stars with long photometric light curves that are suitable for detailed asteroseismic studies has increased substantially…
Shape of the outer stellar warp in the Large Magellanic Cloud disk
Subramanian, S.; Saroon, S.
Warps are vertical distortions of the stellar or gaseous disks of galaxies. One of the proposed scenarios for the formation of warps involves tidal interactions among galaxies. A recent study identified a stellar warp in the outer regions of the south-western (SW) disk of the Large Magellanic Cloud (LMC) and suggested that it might have originated…
Photodynamical analysis of the nearly resonant planetary system WASP-148. Accurate transit-timing variations and mutual orbital inclination
Bonfils, X.; Jenkins, J. M.; Laskar, J. +23 more
WASP-148 is a recently announced extra-solar system harbouring at least two giant planets. The inner planet transits its host star. The planets travel on eccentric orbits and are near the 4:1 mean-motion resonance, which implies significant mutual gravitational interactions. In particular, this causes transit-timing variations of a few minutes, wh…