GCN Circular 25574
Subject
GRB 190829A: Fermi-LAT Upper Limits
Date
2019-08-30T12:37:54Z (5 years ago)
From
Frederic Piron at CNRS/IN2P3/LUPM <piron@in2p3.fr>
F. Piron (CNRS/IN2P3/LUPM), F. Longo (Univ. and INFN Trieste), M.
Axelsson (KTH and Stockholm Univ.), M. Arimoto (Kanazawa Univ.), J. L.
Racusin (NASA/GSFC) and E. Bissaldi (Politecnico and INFN Bari) report
on behalf of the Fermi-LAT Collaboration:
Fermi-LAT observed the position of GRB 190829A, which was detected by
Fermi-GBM (GCN Circ. 25551), Swift (GCN Circ. 25552), and H.E.S.S. (GCN
Circ. 25566). The GRB position was in the LAT field of view at the time
of the GBM trigger (T0= 2019-08-29 19:55:53 UTC), and remained visible
until ~T0+1100 s. No high-energy gamma-ray emission was detected by the
LAT in the initial interval or any subsequent intervals, including
during the H.E.S.S. observations.
LAT upper limits (95% confidence level, 100 MeV - 1 GeV), assuming a
photon index of -2.0, cover the following intervals:
Time Interval �� Energy Flux (erg/cm2/s)���� �� �� Photon Flux (ph/cm2/s)
0-1.1 ks�� �� �� �� �� �� �� ���� 5.3e-10�� �� �� �� �� �� �� �� �� �� �� 1.3e-6
0-10 ks�� �� �� �� �� �� �� �� �� 3.2e-10�� �� �� �� �� �� �� �� �� �� �� 7.9e-7
10-30 ks�� �� �� �� �� �� �� �� 1.4e-10 �� 3.5e-7
15-30 ks (H.E.S.S. interval)�� 1.8e-10�� �� �� �� �� �� �� �� ������ �� 4.3e-7
The Fermi-LAT point of contact for this burst is Frederic Piron
(piron@in2p3.fr).
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.