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Swift Follow-up of Recent Gamma-ray Flaring Activity from PMN J1703-6212

ATel #7369; Bryce Carpenter (CUA/NASA/GSFC) and Roopesh Ojha (NASA/GSFC/UMBC) on behalf of the Fermi LAT Collaboration.
on 11 Apr 2015; 16:31 UT
Credential Certification: Roopesh Ojha (Roopesh.Ojha@gmail.com)

Subjects: Optical, Ultra-Violet, X-ray, Gamma Ray, >GeV, AGN, Blazar, Quasar

Following the gamma-ray detection of flaring activity from the flat spectrum radio quasar PMN J1703-6212 by Fermi/LAT on 2015 March 29 (ATel #7330), two Swift target of opportunity observations were performed, on 2015 April 05 and 07.

Swift/XRT data were taken in Photon Counting mode for a total exposure of about 0.5 ksec and 2.5 ksec, respectively. 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 1.05x10^21 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 fluxes are (1.2^{+1.8}_{-0.8})x10^-12 erg cm^-2 s^-1 and (1.9^{+0.7}_{-0.5})x10^-12 erg cm^-2 s^-1; while the photon indexes are 1.4 +/- 1.1 and 1.4 +/- 0.4, respectively. This flux is approximately a factor of 10 greater than the flux of (1.5^{+2.7}_{-1.3})x10^-13 erg cm^-2 s^-1 observed on 2014 August 01 when this object was in a gamma-ray quiet state.

Simultaneous Swift/UVOT observations were made but in only one filter for each observation. On 2015 April 05, the brightness of PMN J1703-6212 was 17.32 +/- 0.08 mag in the U filter and on 2015 April 07 it was 17.88 +/- 0.09 mag in the W1 filter. In a previous Swift UVOT observation on 2014 July 29 the source was 18.77 +/- 0.23 mag in the W1 filter. This represents an increase by a factor of about 2.4.

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.