Search Publications
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…
A study of globular clusters in a lenticular galaxy in Hydra I from deep HST/ACS photometry
Blakeslee, John P.; Cantiello, Michele; Raimondo, Gabriella +4 more
Aims: We take advantage of exquisitely deep optical imaging data from the Hubble Space Telescope's Advanced Camera for Surveys (HST/ACS) in the F475W (gF475W) and F606W (VF606W) bands to study the properties of the globular cluster (GC) population in the intermediate-mass lenticular galaxy PGC 087327in the Hydra I galaxy…
Doppler shifts of spectral lines formed in the solar transition region and corona
Chen, Yajie; Tian, Hui; Peter, Hardi +2 more
Context. Emission lines formed in the transition region and corona dominantly show redshifts and blueshifts, respectively.
Aims: We investigate the Doppler shifts in a 3D radiation magnetohydrodynamic (MHD) model of the quiet Sun and compare these to observed properties. We concentrate on Si IV 1394 Å originating in the transition region and …
New view of the Balmer-Kapteyn region: Cryptomare distribution and formation
Li, Fei; Yan, Jianguo; Gao, Wutong +4 more
Context. The cryptomare in the Balmer-Kapteyn region is the oldest one on the Moon. Determining the extent and formation of this feature can deepen our understanding of early mare volcanism and help establish temporal and spatial constraints on lunar thermal and volcanic history.
Aims: This paper focuses on the identification of lunar cryptom…
Modelling the correlated keV/TeV light curves of Be/gamma-ray binaries
Takata, J.; Chen, A. M.
Be/γ-ray binaries comprise a confirmed or presumptive pulsar orbiting a Be star and emit luminous γ-rays. Non-thermal emissions are thought to arise from synchrotron radiation and inverse-Compton (IC) scattering in the shock where the pulsar wind is terminated by the stellar outflow. We study wind interactions and shock radiations from such system…