Gamma-ray Burst 210707A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN NOTICE
  

  TITLE:          GCN/INTEGRAL NOTICE
  NOTICE_DATE:    Wed 07 Jul 21 22:25:32 UT
  NOTICE_TYPE:    INTEGRAL Weak
  TRIGGER_NUM:    9296,   Sub_Num: 0
  GRB_RA:         192.3760d {+12h 49m 30s} (J2000),
                  192.7035d {+12h 50m 49s} (current),
                  191.6212d {+12h 46m 29s} (1950)
  GRB_DEC:        -63.2909d {-63d 17' 26"} (J2000),
                  -63.4078d {-63d 24' 27"} (current),
                  -63.0185d {-63d 01' 06"} (1950)
  GRB_ERROR:      3.40 [arcmin, radius, statistical only]
  GRB_INTEN:      7.50 [sigma]
  GRB_TIME:       80720.47 SOD {22:25:20.47} UT
  GRB_DATE:       19402 TJD;   188 DOY;   21/07/07
  SC_RA:          168.11 [deg] (J2000)
  SC_DEC:         -63.31 [deg] (J2000)
  SUN_POSTN:      107.37d {+07h 09m 28s}  +22.48d {+22d 28' 32"}
  SUN_DIST:       107.95 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
  MOON_POSTN:      81.58d {+05h 26m 20s}  +24.19d {+24d 11' 31"}
  MOON_DIST:      120.90 [deg]
  GAL_COORDS:     302.71, -0.42 [deg] galactic lon,lat of the burst
  ECL_COORDS:     225.31,-51.38 [deg] ecliptic lon,lat of the burst
  COMMENTS:       INTEGRAL GRB Coordinates -- this is the weak/subthreshold trigger notice.  
  COMMENTS:       This notice may or may not be followed by a Wakeup/Refined/Offline notice.  
  COMMENTS:       Time_Scale=25.0000 and Time_Error=25.0000.  
  COMMENTS:       Possibly real GRB event (WEAK detection) 
  

• GCN Circular #30414
  S.Mereghetti (INAF, IASF-Milano), D.Gotz (CEA, Saclay), C.Ferrigno, E.Bozzo, V.Savchenko (ISDC, Versoix), L.Ducci (IAAT, Germany and ISDC, Versoix) and J.Borkowski (CAMK, Torun) report:
  a gamma ray burst lasting about 50 s has been detected by IBAS in the IBIS/ISGRI data at 22:25:05 UT of 2021 July 7. The corresponding WEAK type Alert Packet with the burst position was distributed in real time (Alert n. 9296).
  The refined coordinates (J2000) are:

  R.A.= 192.5460 deg
  DEC.=  -63.2763 deg
  

  with an uncertainty of 3 arcmin (90% c.l.).
  The burst had a peak flux of 0.2 ph/cm2/s (20-200 keV, 1-s integration time) and a fluence in the same energy range of about 5e-7 erg/cmq.
  A plot of the light curve is posted at http://ibas.iasf-milano.inaf.it/IBAS_Results.html
• GCN Circular #30420
  C. Fletcher (USRA) reports on behalf of the Fermi-GBM Team:
  INTEGRAL/IBAS detected GRB 210707A at 22:25:05 UT (GCN 30414). There was no Fermi-GBM onboard trigger around the event.
  An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM identified no counterparts.
  The GBM targeted search [1], the most sensitive, coherent search for GRB-like signals identified a transient most significantly on the 8.192 s timescale, with a false alarm rate of 6.4e-06 Hz and a location consistent with the INTEGRAL/IBAS event, using the standard search protocol with a S/N of 15. The GBM targeted search event was found with the highest significance with a "norm" spectrum (Band function with Epeak = 230 keV, alpha = -1.0, beta = -2.3) for a GRB.
  [1] Goldstein et al. 2019 arXiv:1903.12597