We devise a new method for the detection of double-lined binary stars in a sample of the Radial Velocity Experiment survey spectra. The method is based on the properties and shape of the cross-correlation function, and is able to recover ~80% of all binaries with an orbital period of order 1 day. We have applied the method to 25,850 spectra of the RAVE second data release and found 123 double-lined binary candidates. Among the candidates, there are seven that show spectral features consistent with the RS CVn type and seven that might be of W UMa type. One star seems to be a triple system.
COBISS.SI-ID: 364161
The distances are determined with a new method where we assume that the star undergoes a standard stellar evolution. Errors on distances, using comparison to Hipparcos astrometry, open and globular clusters and repeated observations, are between 11 and 21%. RAVE dwarfs are ~300 pc from the Sun, and most giants are at distances of 1 to 2 kpc. This places the RAVE dataset between the more local Geneva-Copenhagen survey and the more distant and fainter SDSS sample. As such it is ideal to address some of the fundamental questions of Galactic structure and evolution in the pre-Gaia era.
COBISS.SI-ID: 363905
This paper applies the normal-mode functions for the three-dimensional diagnosis of systematic analysis increments in the operational systems of ECMWF and NCEP, in the NCEP/NCAR re-analyses and in the ensemble data assimilation system DART/CAM which is developed at NCAR. Non-zero systematic increments are interpreted as the analysis system bias. Spectra of analysis increments averaged over one month show that, on average, 20% to 45% of total energy in increment fields belongs to the inertio-gravity motions.
COBISS.SI-ID: 2218596
We studied properties of GRB 090902B and found that optical and infrared light curves are well described with standard fireball model, while X-ray light curve is decaying faster than compatible with this model. Early optical data indicate presence of a reverse shock. We calculated the collimation-corrected gamma energy to be above 2.2 x 10^45 J, one of the highest ever seen in a long-duration gamma-ray bursts.
COBISS.SI-ID: 347521
We use a sample of 19 gamma-ray bursts (GRBs) that exhibit single-peaked optical light curves to test the standard fireball model. We produce expected radio light curves by predicting the temporal evolution of the expected radio emission from forward and reverse shock components, including early synchrotron self-absorption effects. Future detections of reverse-shock radio flares with new radio facilities such as the EVLA and ALMA will be able to test the low-frequency model and provide constraints on magnetic models.
COBISS.SI-ID: 360321