Swift Follow-up of Recent Gamma-ray Flaring Activity from the FSRQ B2 1846+32B
ATel #8340; Roopesh Ojha (NASA/GSFC/UMBC) and Bryce Carpenter (CUA/NASA/GSFC) on behalf of the Fermi Large Area Telescope Collaboration
on 26 Nov 2015; 16:33 UT
Credential Certification: Roopesh Ojha (Roopesh.Ojha@gmail.com)
Subjects: Ultra-Violet, X-ray, Gamma Ray, >GeV, AGN, Blazar, Quasar
Following the gamma-ray detection of flaring activity from the flat spectrum radio quasar (FSRQ) B2 1846+32B by Fermi-LAT (>100 MeV) on 19 November 2015 (ATel #8315), a Swift target of opportunity observation was performed on 21 November 2015.
Swift/XRT data were taken in Photon Counting mode for a total exposure of about 5 ksec. The X-ray spectrum (0.5-10 keV) can be fit by an absorbed power-law model with an HI column density set to the Galactic value of 8.35x10^20 cm^-2 (Kalberla et al. 2005, A&A, 440, 775) using the abundances of Wilms et al. (2000, ApJ, 542, 914) and the cross sections of Verner et al. (1996, ApJ, 465, 487). The observed flux is (4.4^{+0.8}_{-0.7})x10^-12 erg cm^-2 s^-1 with a photon index of 1.3 +/- 0.2. This is approximately 4.4 times the flux observed on 16 January 2013 when the object was not in an elevated gamma-ray state.
A simultaneous Swift/UVOT observation was made with the UVM2 filter yielding a magnitude of 16.64+/-0.07. We do not find any past observations to compare this to.
Further multiwavelength observations are encouraged. For this source the Fermi-LAT contact person is Roopesh Ojha (Roopesh.Ojha@gmail.com).
We would like to thank the Swift Team for making these observations possible, in particular K. L. Page as the Swift Observatory Duty Scientist.
