Keck Optical Spectra of the Counterpart of IGR J00291+5934 Keck Optical Spectra of the Counterpart of IGR J00291+5934
ATel #366; A. V. Filippenko, R. J. Foley (University of California, Berkeley), P. J. Callanan (Cork University)
on 13 Dec 2004; 10:44 UT
Credential Certification: Alexei V. Filippenko (alex@astro.berkeley.edu)
Subjects: Optical, Binary, Neutron Star, Transient, Pulsar
Referred to by ATel #: 1660
Inspection of CCD spectra (range 320-940 nm) obtained on Dec. 12 UT with the
Keck I 10-m telescope (+ LRIS; integration time 300 s on each of the blue and
red sides) shows that the object detected by Fox & Kulkarni (ATEL #354) does
indeed appear to be the optical counterpart to IGR J00291+5934 (ATEL #352), as
was also noted by Roelofs et al. (ATEL #356). Superposed on the blue continuum
are broad (FWHM = 1200 km/s) emission lines of H-alpha (equivalent width 0.96
nm), H-beta (EW = 0.54 nm), and He I 667.8 nm (EW = 0.1 nm), as well as narrow
(FWHM = 300 km/s), very weak (EW = 0.06 nm) He II 468.6 nm emission.