NICER / ISS Science Nugget
for September 5, 2019
NICER makes its first detection of a GRB afterglow
On September 3rd 2019, NICER responded to a Target of Opportunity (TOO) request to observe a Gamma-Ray Burst (GRB)
"afterglow" detected by NASA's Swift and Fermi orbiting observatories on August 29th. This transient event, known as GRB
190829A, is at a redshift of 0.078, corresponding to a distance of about 356 Megaparsecs away, making it one of the
nearest GRBs ever seen.
NICER detected X-rays over a 23 ksec observation from September 3rd through September 5th (see
figure). This is NICER's first positive detection of X-rays from a GRB. NICER will continue to observe this target to
look for emission lines in the burst afterglow and track its evolution.
Quicklook NICER data (red) shows detection of a clear excess over the expected background rate (green) from GRB190829A.