TITLE:   GCN CIRCULAR
NUMBER:  30726
SUBJECT: GRB 210827B: Fermi GBM Final Real-time Localization
DATE:    21/08/27 10:20:35 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 10:10:16 UT on 27 Aug 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210827B (trigger 651751821.143562 / 210827424).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 308.8, Dec = -19.3 (J2000 degrees, equivalent to J2000 20h 35m, -19d 18'), with a statistical uncertainty of 2.5 degrees.

The angle from the Fermi LAT boresight is 66.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210827424/quicklook/glg_skymap_all_bn210827424.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210827424/quicklook/glg_healpix_all_bn210827424.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210827424/quicklook/glg_lc_medres34_bn210827424.gif