MDM optical spectroscopy of Swift J1357.2-0933
ATel #3146; D. Milisavljevic, R. A. Fesen, J. T. Parrent, and J. R. Thorstensen
on 4 Feb 2011; 14:22 UT
Credential Certification: J. R. Thorstensen (john.thorstensen@dartmouth.edu)
Subjects: Optical, Neutron Star, Transient
Referred to by ATel #: 3206
A 30 min spectrum of the optical counterpart to the new X-ray transient
Swift J1357.2-0933 (Krimm et al. ATel #3138) was acquired with the CCDS
spectrograph on the 2.4m Hiltner telescope at MDM Observatory on 2011
Feb 03 12:41 UT. A 1.5 arcsec slit provided spectral resolution of R~500
in the range 4200-7800 Angstroms.
Emission centered around the Halpha and Hbeta lines is weakly detected
on top of a blue continuum. The emission equivalent width of Halpha is
about 7 Angstroms, while that of Hbeta is around 4 Angstroms.
The FWZI of Halpha is roughly 4000 km/s. We note that no emission lines
were detected in a spectrum reported by Torres et al. (ATel #3143),
suggesting that the optical spectrum evolved during the 15 hours that
intervened between their observation and ours.
