6 papers · 1 filter
Coronae of Cool Stars
M. Audard, S. A. Drake, M. Güdel +6
We present preliminary results of grating observations of YY Mensae and V824 Arae by Chandra and XMM-Newton. Spectral features are presented in the context of the emission measure…
Hard X-ray Observations of Magnetic Cataclysmic Variables
K. P. Singh, V. R. Rana, K. Mukerjee +2
Hard X-ray light curves and spectral parameters from our analysis of X-ray data of five AM Her type systems - V2301 Oph, V1432 Aql, EP Draconis, GG Leonis, V834 Cen, and one interm…
A New Narrow-Line Seyfert 1 galaxy : RXJ1236.9+2656
G. C. Dewangan, K. P. Singh, Paula Szkody +1
We report identification of a narrow-line Seyfert 1 galaxy RXJ1236.9+2656. X-ray emission from the NLS1 galaxy undergoes long-term variability with 0.1--2.0 keV flux changing by a…
Discovery of a narrow line Seyfert 1 galaxy
K. P. Singh, L. R. Jones
We have discovered a Narrow-Line Seyfert 1 (NLS1) galaxy and identified it with an ultrasoft X-ray source RX 215319-1514 detected with ROSAT. We present its X-ray and optical spect…
An ultra-soft X-ray source (RX 215319-1514) and discovery of a narrow line Seyfert 1 galaxy
Kulinder Pal Singh, Laurence R. Jones
Two optical candidates - a galaxy and a star, are found within the error circle of the X-ray source position of an ultra-soft X-ray source discovered with ROSAT. Optical spectrosco…
Torque-luminosity correlation and possible evidence for core-crust relaxation in the X-ray pulsar GX 1+4
B. Paul, A. R. Rao, K. P. Singh
We present the detection of a positive correlation between spin-down rate and pulsed X-ray luminosity in the BATSE archival data of the bright hard X-ray pulsar GX 1+4. W…