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Fermi LAT detection of a GeV flare from MG2 J071354+1934

ATel #2110; E. Hays (NASA GSFC) and M. Marelli (INAF/IASF Milano) on behalf of the Fermi Large Area Telescope Collaboration
on 5 Jul 2009; 06:05 UT
Credential Certification: Elizabeth Hays (elizabeth.a.hays@nasa.gov)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN

The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed an increasing gamma-ray flux from a source positionally consistent with a flat-spectrum radio source, MG2 J071354+1934 (RA:07h13m55.7s, DEC:+19d35m00s, J2000) (Petrov, L., Kovalev, Y. Y., Fomalont, E., & Gordon, D. 2005, The Astronomical Journal, 129, 1163). MG2 J071354+1934 does not have a reported redshift in NED.

Preliminary analysis indicates that on 3 July 2009 this source was in a high state with a gamma-ray flux (E>100MeV) of (1.0 +/- 0.3) x 10-6 ph cm-2 s-1 (statistical error). For that day the flux increased a factor of 6 above the average flux level observed over the past months. The source was not significantly detected on daily time scales preceding this flare. It has been reported as a gamma-ray detection previously in the 3-month LAT bright source list as 0FGL J0714.2+1934 (Abdo, A. A., et al. 2009, The Astrophysical Journal Supplement, 183, 46). The average gamma-ray flux (100 MeV to 100 GeV) reported for observations from August through October was (1.0 +/- 0.2) x 10-7 ph cm-2 s-1 (sum of flux in energy bands 100 MeV to 1 GeV and 1 GeV to 100 GeV).

Because Fermi operates in an all-sky scanning mode, regular gamma-ray monitoring of this source will continue.

In consideration of the ongoing activity of this source we strongly encourage multiwavelength observations. Some observations of this location are limited by the proximity of the Sun, currently about 6 deg away. For this source the Fermi LAT contact person is D. J. Thompson (david.j.thompson@nasa.gov).

The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.