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Fermi LAT detection of a GeV flare from the high-redshift blazar PKS 1329-049

ATel #2728; D. Donato (NASA/GSFC), on behalf of the Fermi Large Area Telescope Collaboration
on 9 Jul 2010; 21:51 UT
Credential Certification: Davide Donato (davide.donato-1@nasa.gov)

Subjects: Gamma Ray, Blazar

Referred to by ATel #: 2739, 2837

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 PKS 1329-049 (1FGL J1331.9-0506, Abdo et al. 2010, ApJS, 188, 405; RA=13h32m04.4646s, Dec=-05d09'43.305", J2000, Beasley et al. 2002, ApJS, 141, 13), a flat spectrum radio quasar at z=2.15 (Thompson et al. 1990, PASP, 102, 1235). High redshift sources detected by LAT have been already reported (e.g., B3 1343+451, ATel #2217 and PKS 1915-458, ATel #2666).

Preliminary analysis indicates that the source on July 07, 2010 was in a high state with a gamma-ray flux (E>100MeV) of (1.0 +/-0.3) x10^-6 photons cm^-2 s^-1 (errors are statistical only), representing more than four times its average flux during the first 11 months of Fermi observations (Abdo et al. 2010). The source was previously detected by LAT on a 1-day timescale at comparable flux levels on Sept. 22, 2009.

Since Fermi operates in an all-sky scanning mode, regular monitoring of this source will continue. In consideration of the ongoing activity of this source we strongly encourage multiwavelength observations. The Fermi LAT contact person for this source is D. Donato (donato@milkyway.gsfc.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.