Fermi/GBM detection of the Be/XRB KS 1947+300
ATel #13201; C. Malacaria (NASA-MSFC/USRA), P. Jenke (UAH-SPA/CSPAR),O. J. Roberts (USRA/MSFC), C. A. Wilson-Hodge (NASA/MSFC)
on 18 Oct 2019; 22:05 UT
Credential Certification: Christian Malacaria (cmalacaria@usra.edu)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
Referred to by ATel #: 13433
We report on recent observations with Fermi/GBM of the transient Be/X-ray binary system KS 1947+300. GBM detected pulsations from the source starting on October 13 (MJD 58769), with a pulsed flux in the 12-50 keV band of 0.105+/-0.017 keV cm^-2 s^-1. At that time, the source spin frequency was 53.3761(2) mHz. As of October 17 (MJD 58773), the pulsed flux of the source had increased to 0.157+/-0.022 keV cm^-2 s^-1, and pulsations are being detected at a frequency of 53.3768(2) mHz, with an average spin-up rate of 2.0x10^-12 Hz/s (typical of accreting X-ray pulsars). The last GBM detection of this source was in March 2015 (MJD 57088), when the source was undergoing a periastron outburst and pulsations were detected at a spin frequency of 53.3165(2) mHz.
The GBM pulse history of this source can be found at: https://gammaray.msfc.nasa.gov/gbm/science/pulsars/lightcurves/ks1947.html
We encourage further observations with X-ray observatories and multi-wavelength facilities.
The GBM Pulsar project
