The Orbital Period of IGR J19140+098
ATel #269; R. H.D. Corbet (NASA/GSFC and USRA), D. C. Hannikainen (University of Helsinki Observatory), & R. Remillard (MIT)
on 15 Apr 2004; 19:08 UT
Credential Certification: Robin Corbet (corbet@gsfc.nasa.gov)
Subjects: X-ray, Binary, Black Hole, Neutron Star, Transient
The power spectrum of the Rossi X-ray Timing Explorer All Sky Monitor
light curve of IGR J19140+098 (Hannikainen, Rodriguez, & Pottschmidt 2003,
IAUC # 8088 ) obtained between February 24 1996 and April 8 2004 shows a
strong modulation at a period of 13.55 days. The mean flux measured with
the ASM during this interval is 0.4 counts/s (= 5 mCrab) and the Fourier
amplitude of the modulation is 0.14 counts/s. A sine wave fit to the ASM
light curve gives parameters of: period = 13.558 +/- 0.004 days and epoch
of maximum flux = MJD 51593.4 +/- 0.32 The persistence of this period
suggests that it arises from the orbital period of an X-ray binary. It is
noted that this modulation is also detectable in just the first 3 years
of ASM observations indicating activity from this source at that time.
