New flaring activity in PKS 1510-089
ATel #3509; M. Hauser, J. P.Lenain, S. Wagner (LSW Heidelberg), H. Hagen (Sternwarte Hamburg)
on 26 Jul 2011; 17:29 UT
Credential Certification: Stefan J. Wagner (swagner@lsw.uni-heidelberg.de)
Subjects: Optical, Gamma Ray, >GeV, Request for Observations, AGN, Blazar, Quasar, Transient
Referred to by ATel #: 3523
Following the bright flare in PKS 1510-089 reported by the AGILE and
Fermi-LAT teams in ATel #3470 and Atel #3473 and reports on activities
in the radio band (ATel #3500) the Automatic Telescope for Optical Monitoring
(ATOM) recorded an increase in the optical flux of this object on July 24-25 and July 25-26
(JD 2455767.3, 2455768.3) with R band magnitudes of 15.7 and 15.3,
respectively. Variations of 25% were recorded on a timescale of one hour.
Motivated by the increased activity of PKS 1510-089 in optical data
a preliminary analysis of Fermi/LAT public data indicates that the source
reached a gamma-ray (E>200 MeV) peak flux of (4.7 +/- 0.7)e-6 ph cm^-2 s^-1
(statistical uncertainty only) centered on July 25, 2011 12:50 UTC, in an
analysis performed with time bins of 4 hours. The source flux then reveals a
decreasing trend up to July 26, 06:50 UTC. The corresponding daily
averaged flux in the 100 MeV-300 GeV energy range is comparable to the
one reported for another flare that occurred in the same source at the
beginning of July 2011 (ATel #
3473).