6 papers
RR Lyrae search and stellar populations study in Canis Major: Preliminary Results
Cecilia E. Mateu, A. Katherina Vivas, Robert Zinn +1
We present preliminary results of a RR Lyrae star search and stellar populations study performed in the Canis Major overdensity, spanning an area of 8.35sq deg. The observations we…
VLT Spectroscopy of RR Lyrae Stars in the Sagittarius Tidal Stream
A. Katherina Vivas, Robert Zinn, Carme Gallart
Sixteen RR Lyrae variables from the QUEST survey that lie in the leading arm of the tidal stream from the Sagittarius dSph galaxy have been observed spectroscopically to measure th…
Mapping Tidal Streams around Galactic Globular Clusters
David Martinez-Delgado, Dana I. Dinescu, Robert Zinn +3
The surroundings of globular clusters in the outer halo are one of the best places to look for the remnants of ancient dwarf satellites. The classical Searle & Zinn (1978) scenario…
The Selection of RR Lyrae Stars Using Single-epoch Data
Zeljko Ivezic, A. Katherina Vivas, Robert H. Lupton +1
We utilize a complete sample of RR Lyrae stars discovered by the QUEST survey using light curves to design selection criteria based on SDSS colors. Thanks to the sensitivity of the…
Velocities of RR Lyrae Stars in the Sagittarius Tidal Stream
A. Katherina Vivas, Robert Zinn, Carme Gallart
We have measured radial velocities and metallicities of 16 RR Lyrae stars, from the QUEST survey, in the Sagittarius tidal stream at 50 kpc from the galactic center. The distributi…
HST Photometry of the Fornax dSph Galaxy: cluster 4 and its field
R. Buonanno, C. E. Corsi, M. Castellani +3
Using observations from the Hubble Space Telescope archive, color-magnitude diagrams (CMDs) have been constructed for globular cluster 4 in the Fornax dSph galaxy and its surroundi…