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Sustained and increasing gamma-ray activity of the blazar PKS 0454-234

ATel #3703; F. Hungwe (Rhodes U, HartRAO), M. Dutka (Catholic U), R. Ojha (NASA/GSFC), L. Escande (CENBG), & F. K. Schinzel (MPIfR), on behalf of the Fermi Large Area Telescope Collaboration
on 23 Oct 2011; 23:59 UT
Credential Certification: Roopesh Ojha (Roopesh.Ojha@gmail.com)

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

Referred to by ATel #: 3713, 3722, 4647, 5583

The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed a sustained and increasing gamma-ray flux from a source positionally consistent with the flat spectrum radio quasar PKS 0454-234 (2FGL J0457.0-2325, 1FGL J0457.0-2325; RA: 04h57m03.179s Dec: -23d24m52.02s Johnston et al., 1995, AJ, 110, 880) at z=1.003 (Stickel et al., 1989, A&AS, 80, 103). It has been significantly detected almost every day for the last two weeks, reaching a daily averaged flux of (1.7+/-0.2) x 10^-6 on 22 October 2011 and a peak flux of (2.8+/-0.4) x 10^-6 photons cm^-2 s^-1 on a 6h time scale between 06:00 and 12:00 UT on the same day.

This is only the second time that this source has been detected by Fermi on daily/six-hourly timescales. The first detection was in January 2009 when it reached a flux of (1.96+/-0.30) x10-6 photons cm-2 s-1 (ATel #1898). This source is one of the "LAT Monitored Sources" and consequently a preliminary estimation of the daily gamma-ray flux observed by Fermi/LAT is publicly available at http://fermi.gsfc.nasa.gov/FTP/glast/data/lat/catalogs/asp/current/lightcurves/PKS0454-234_86400.png

Because Fermi operates in an all-sky scanning mode, regular gamma-ray monitoring of this source will continue. Multiwavelength observations during the ongoing activity of this source are strongly encouraged. For this source the Fermi LAT contact persons are Faith Hungwe (faith.hungwe@gmail.com) and Dario Gasparrini (dario.gasparrini@asdc.asi.it).

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.