Fermi LAT Detection of a New Gamma-ray Transient in the Galactic Plane J0902-4624
ATel #3972; R. Ojha (NASA/GSFC), E. Hays (NASA/GSFC), C. C. Cheung (NRC/NRL), M. Dutka (Catholic U.); on behalf of the Fermi Large Area Telescope Collaboration
on 16 Mar 2012; 22:03 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Roopesh Ojha (Roopesh.Ojha@gmail.com)
Subjects: Gamma Ray, >GeV, Request for Observations, Transient
The Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope, has detected a transient gamma-ray source in the Galactic Plane starting on 15 March 2012. The preliminary LAT position is (J2000.0): RA = 135.56 deg, Dec = -46.41 deg, (l, b = 267.47 deg, 0.07 deg) with a 68% confidence error circle radius 0.23 deg (statistical uncertainty only).
Preliminary analysis of the Fermi-LAT data indicates that on 15 March 2012 the source was detected with a flux (E >100 MeV) of 1.2+/-0.3 x 10^-6 ph cm^-2 s^-1. CAUTION: This source is 4 degrees from the Vela pulsar which is the brightest persistent gamma-ray source in the sky. Owing to the limited statistics in a daily data set and the large size of the LAT PSF the systematic uncertainties on the flux and position measurements for the new transient source are relatively large.
The source was not detected previously by the LAT and there is no previously reported EGRET gamma-ray detection at this location.
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. For this source the Fermi LAT contact person is Elizabeth Hays (elizabeth.a.hays@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.
