Fermi LAT detection of increasing gamma-ray activity of blazar B3 0650+453
ATel #3580; K. V. Sokolovsky (ASC Lebedev/SAI MSU) on behalf of the Fermi Large Area Telescope Collaboration
on 24 Aug 2011; 17:43 UT
Credential Certification: Kirill Sokolovsky (ksokolov@mpifr-bonn.mpg.de)
Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazar, Quasar
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 B3 0650+453 also known as
CGRaBS J0654+4514 and 2FGL J0654.2+4514 (VLBI position:
06:54:23.7136 +45:14:23.545, J2000; Beasley et al. 2002, ApJS, 141, 13),
a flat spectrum radio quasar at z=0.933
(Henstock et al. 1997, MNRAS, 290, 380).
Preliminary analysis indicates that the source on 2011 August 22 was in a
high state with a gamma-ray flux (E>100MeV) of (1.0 +/-0.2) x10^-6 photons
cm^-2 s^-1, which represents an order of magnitude increase with respect
to the average flux level indicated in 2FGL (Abdo et al. 2011,
arXiv:1108.1435). The source has also been detected by LAT on the one-day
timescale on August 20, 21, and 23 with the flux of (0.4 +/-0.1),
(0.9 +/-0.2) and (0.6 +/-0.2) x10^-6 photons cm^-2 s^-1, respectively.
The quoted uncertainties are statistical only.
Because Fermi operates in an all-sky scanning mode, regular gamma-ray
monitoring of this source will continue. B3 0650+453 will be added to
the LAT monitored sources list available at: http://fermi.gsfc.nasa.gov/ssc/data/access/lat/msl_lc/
We encourage follow-up multiwavelength observations.
The Fermi LAT contact person for this source is
Kirill Sokolovsky (ksokolov@mpifr-bonn.mpg.de).
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.
