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Iron-Group Abundances in the Metal-Poor Main Sequence Turnoff Star HD~84937
(2016-01-20)
We have derived new very accurate abundances of the Fe-group elements Sc through Zn (Z = 21-30) in the bright main-sequence turnoff star HD 84937, based on high-resolution spectra covering the visible and ultraviolet ...
Extended H2 emission line sources from UWISH2
(2015-12-11)
We present the extended source catalogue for the UKIRT Wide Field Infrared Survey for H2 (UWISH2). The survey is unbiased along the inner Galactic Plane from l≈357deg to l≈65deg and |b| ≤ 1 ∘.5 and covers 209 deg2. A further ...
Extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way
(2015-11-26)
The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars with tiny amounts of elements heavier than ...
The OmegaWhite Survey for Short-Period Variable Stars - I : Overview and First Results
(2015-11-21)
We present the goals, strategy and first results of the OmegaWhite survey: a wide-field high-cadence g-band synoptic survey which aims to unveil the Galactic population of short-period variable stars (with periods <80 min), ...
Radio monitoring of the periodically variable IR source LRLL 54361: No direct correlation between the radio and IR emissions
(2015-11-12)
LRLL 54361 is an infrared source located in the star forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 during roughly one week every 25.34 days. To understand the origin of these ...
Probing M subdwarf metallicity with an esdK5+esdM5.5 binary
(2015-10-15)
We present a spectral analysis of the binary G 224-58 AB that consists of the coolest M extreme subdwarf (esdM5.5) and a brighter primary (esdK5). This binary may serve as a benchmark for metallicity measurement calibrations ...
YSOVAR: Mid-infrared Variability Among YSOs in the Star Formation Region GGD 12-15
(2015-10-12)
We present an IR-monitoring survey with the $Spitzer$ Space Telescope of the star forming region GGD 12-15. Over 1000 objects were monitored including about 350 objects within the central 5 arcminutes which is found to be ...
Classical T Tauri stars with VPHAS+ -I : H α and u-band accretion rates in the Lagoon Nebula M8
(2015-10-11)
We estimate the accretion rates of 235 Classical T Tauri star (CTTS) candidates in the Lagoon Nebula using $ugri$H$\alpha$ photometry from the VPHAS+ survey. Our sample consists of stars displaying H$\alpha$-excess, the ...
Starspot distributions on fully convective M dwarfs : implications for radial velocity planet searches
(2015-10-07)
Since M4.5 - M9 dwarfs exhibit equatorial rotation velocities of order 10 km/s on average, radial velocity surveys targeting this stellar population will likely need to find methods to effectively remove starspot jitter. ...
YSOVAR: mid-infrared variability of young stellar objects and their disks in the cluster IRAS 20050+2720
(2015-09-22)
We present a time-variability study of young stellar objects in the cluster IRAS 20050+2720, performed at 3.6 and 4.5 micron with the Spitzer Space Telescope; this study is part of the Young Stellar Object VARiability ...