Search Publications
Absolute V-band magnitudes and mass-to-light ratios of Galactic globular clusters
Hilker, M.; Baumgardt, H.; Sollima, A.
We have used Hubble Space Telescope and ground-based photometry to determine total V-band magnitudes and mass-to-light ratios of more than 150 Galactic globular clusters. We do this by summing up the magnitudes of their individual member stars, using colour-magnitude information, Gaia DR2 proper motions, and radial velocities to distinguish cluste…
A SETI survey of the Vela region using the Murchison Widefield Array: Orders of magnitude expansion in search space
Tremblay, C. D.; Tingay, S. J.
Following the results of our previous low-frequency searches for extraterrestrial intelligence (SETI) using the Murchison Widefield Array (MWA), directed towards the Galactic Centre and the Orion Molecular Cloud (Galactic Anticentre), we report a new large-scale survey towards the Vela region with the lowest upper limits thus far obtained with the…
Investigation on the mass transferring near-contact binary TT Cet
Tian, Xiao-Man; Chang, Lin-Feng
First multi-colour complete light curves and low-resolution spectra of short-period eclipsing binary TT Cet are presented. The stellar atmospheric parameters of the primary star were derived through spectra fitting as: $T_{eff}=7 091±124 {K}$, $\log g = 4.15±0.33 {cm}/s^2$, and $[Fe/H]=-0.23±0.04 dex$. The light curves were analysed using the Wils…
The stellar rotation-activity relation for a sample of SuperWASP and ASAS-SN field stars
Thiemann, Heidi B.; Norton, Andrew J.; Kolb, Ulrich C.
It is well established that late-type main-sequence (MS) stars display a relationship between X-ray activity and the Rossby number, Ro, the ratio of rotation period to the convective turnover time. This manifests itself as a saturated regime (where X-ray activity is constant) and an unsaturated regime (where X-ray activity anti-correlates with Ros…
A hundred new eclipsing binary system candidates studied in a near-infrared window in the VVV survey
Minniti, D.; Saito, R. K.; Palma, T. +4 more
We present the first results obtained from an extensive study of eclipsing binary (EB) system candidates recently detected in the VISTA Variables in the Vía Láctea (VVV) near-infrared (NIR) Survey. We analyse the VVV tile d040 in the southern part of the Galactic disc wherein the interstellar reddening is comparatively low, which makes it possible…
Bridging the ultraviolet and optical regions: Transformation equations between GALEX and UBV photometric systems
Bilir, S.; Ak, T.; Yontan, T. +6 more
We derive transformation equations between GALEX and UBV colours by using the reliable data of 556 stars. We present two sets of equations: as a function of (only) luminosity class and as a function of both luminosity class and metallicity. The metallicities are provided from the literature, while the luminosity classes are determined by using the…
A survey of extended matter around chromospherically active binary systems
Karakuş, Osman; Ekmekçi, Fehmi
We present an analysis of colour excess (CE) observations for 13 chromospherically active binary systems, together with 27 inactive reference stars of similar spectral types and luminosity classes of the components of these 13 binaries. We used the observations which were made by Johnson-Cousins BVRcIc , 2MASS, and WISE photo…