Search Publications
Chemical composition of the young massive cluster NGC 1569-B
Larsen, S. S.; Beasley, M. A.; Brodie, J. +1 more
Context. The chemical composition of young massive clusters (YMCs) provides stellar population information on their host galaxy. As potential precursors of globular clusters (GCs), their properties can help us understand the origins of GCs and their evolution.
Aims: We present a detailed chemical abundance analysis of the YMC NGC 1569-B. The …
eROSITA X-ray scan of the η Chamaeleontis cluster. Member study and search for dispersed low-mass stars
Schmitt, J. H. M. M.; Czesla, S.; Robrade, J. +2 more
Context. The nearby young open cluster η Chamaeleontis has been observed by eROSITA/SRG during its CalPV phase for 150 ks. The extended ROentgen Survey with an Imaging Telescope Array (eROSITA) data were taken in the field-scan mode, an observing mode of Spectrum-Roentgen-Gamma (SRG) that follows a rectangular grid-like pattern, here covering a 5 …
Unveiling wide-orbit companions to K-type stars in Sco-Cen with Gaia EDR3
Henning, Thomas; Brown, Anthony G. A.; Ginski, Christian +12 more
Context. The detection of low-mass companions to stellar hosts is important for testing the formation scenarios of these systems. Companions at wide separations are particularly intriguing objects as they are easily accessible for variability studies of the rotational dynamics and cloud coverage of these brown dwarfs or planetary-mass objects.
Infrared-radio relation in the local Universe
De Zotti, G.; Tisanić, K.; Amiri, A. +3 more
Context. The Square Kilometer Array (SKA) is expected to detect high-redshift galaxies with star formation rates (SFRs) up to two orders of magnitude lower than Herschel surveys and will thus boost the ability of radio astronomy to study extragalactic sources. The tight infrared-radio correlation offers the possibility of using radio emission as a…
Abundance of zirconium in the globular cluster 47 Tucanae: a possible Zr-Na correlation?*
Bonifacio, P.; Korotin, S.; Kučinskas, A. +2 more
We determined abundances of Na and Zr in the atmospheres of 237 RGB stars in Galactic globular cluster (GGC) 47 Tuc (NGC 104), with a primary objective of investigating possible differences between the abundances of Zr in the first generation (1P) and second generation (2P) stars. For the abundance analysis, we used archival UVES/GIRAFFE spectra o…
KMT-2017-BLG-0673Lb and KMT-2019-BLG-0414Lb: Two microlensing planets detected in peripheral fields of KMTNet survey
Han, Cheongho; Lee, Chung-Uk; Zang, Weicheng +18 more
Aims: We investigate the microlensing data collected during the 2017-2019 seasons in the peripheral Galactic bulge fields with the aim of finding planetary signals in microlensing light curves observed with relatively sparse coverage.
Methods: We first sort out lensing events with weak short-term anomalies in the lensing light curves fro…
Probing the surface environment of large T-type asteroids
Hasegawa, Sunao; Agarwal, Jessica; Fornasier, Sonia +2 more
Context. The thermal and radiative environments encountered by asteroids have shaped their surface features. Recent observations have focused on asteroids in the main belt and showed indications for ices and organics in the interiors of the asteroids that were likely significant on prebiotic Earth. They stand out in reflectance spectra as darker, …
X-ray emission of contact binary variables within 1 kpc
Esamdin, Ali; Gu, Wei-Min; Liu, Junhui +3 more
Aims: The X-ray emission of contact binaries (EW-type) is an important facet of such systems. Thus, X-ray emitting EW-type binaries (EWXs) are ideal laboratories for studying the X-ray radiation saturation mechanisms as well as binary evolution. By assembling the largest sample to date of EWXs with periods of less than 1 day from the All-Sky …
XMM-Newton and TESS observations of the highly variable polar V496 UMa
Schwope, Axel; Ok, Samet
Aims: We studied the temporal and spectral behavior of V496 UMa from the optical to the X-ray regimes.
Methods: We used archival XMM-Newton and TESS observations obtained in 2017 and 2019, respectively, to perform a spectral and timing analysis of the highly variable magnetic CV.
Results: The light curves of the TESS and XMM-Newton …
Bayesian approach for modeling global magnetic parameters for the solar active region
Mandrini, C. H.; Démoulin, P.; Grings, F. +2 more
Context. Active regions (ARs) appear in the solar atmosphere as a consequence of the emergence of magnetic flux tubes. The presence of elongated magnetic polarities in line-of-sight (LOS) magnetograms indicates the existence of twist in the flux tubes that form them. These polarity elongations, referred to as magnetic tongues, bias the measurement…