NICER observation list: Target ID 261102

Abstract

We propose observing CAL 83 and MR Vel, two supersoft X-ray binaries, one in the Large Magellanic Cloud and one in the Galaxy. We will measure possible spectral changes over a period of many years since the last X-ray observations, and periodic modulations with time scales of tens of seconds or tens of minutes. The high luminosity and the not-exceedingly-supersoft spectrum of these two targets makes them ideal candidates for NICER, both from the point of view of feasibility and scientific interest and return. We will monitor the evolution and the amplitude changes of a 67 s period of CAL 83, search for short periodicities in the light curve of MR Vel, and measure again other, longer periods, of 38 minutes and 1 hour respectively, observed several years ago in each the two sources.
Obsid RA DEC l b Start End Exposure Number of
Modules
Number of
Processing
Status of
Processing
Date of
Processing
Public
date
2611020101 141.442 -47.971 271.355 1.884 58621.9018 58621.9863 2531.0 52 3 VALIDATED 58625.7 58815
2611020102 141.441 -47.971 271.354 1.884 58622.0305 58622.9560 8565.0 52 3 VALIDATED 58626.7 58816
2611020103 141.440 -47.971 271.353 1.884 58622.9958 58623.3352 9905.0 52 3 VALIDATED 58627.6 58817