The Astronomer's Telegram
Telegram Index | Search
To The Parent Site

[ Previous | Next ]

Fermi LAT detection of a possible new gamma-ray blazar PMN J1913-3630

ATEL # 2966; D. Donato (NASA/GSFC), C.C. Cheung (NRC, resident at NRL), on behalf of the Fermi LAT Collaboration
on 22 Oct 2010; 22:55 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Teddy Cheung (

Subjects: >GeV, Transients
Referred to by ATEL #: 2980

The Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope, has observed a gamma-ray flare from a source positionally consistent with the flat spectrum radio source PMN J1913-3630, also known as VCS4 J1913-3630 (RA = 19:13:20.89, Dec = -36:30:19.4, J2000; L. Petrov et al. 2006 AJ 131, 1872). The source has no known redshift.

Preliminary analysis indicates that the source on October 21, 2010 showed a bright gamma-ray outburst with a daily flux (E>100MeV) of (1.3 +/- 0.3) x 10^-6 ph cm^-2 s^-1 and a peak of (2.3 +/- 0.7) x 10^-6 ph cm^-2 s^-1 (errors are statistical only) observed between 18:00 and 22:00 UT. The source was not detected previously by the LAT (Abdo et al. 2010, ApJS 188, 405) and there is no previously reported EGRET gamma-ray detection at this location.

Because Fermi operates in all-sky survey mode, gamma-ray monitoring of this source will continue. In consideration of the activity of this source we strongly encourage multiwavelength observations. The Fermi LAT contact person for this source is D. Donato (

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.

[ Telegram Index ]

R. E. Rutledge , Editor
ATEL Mirror v1.0 Updates