Gamma-ray Burst 210208A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #29429
  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 3 s has been detected by IBAS in the IBIS/ISGRI data at 13:32:23 UT of February 8, 2021.
  The refined coordinates (J2000) are:

  R.A.=  260.1976  deg
  DEC.=  -12.6667 deg
  

  with an uncertainty of 2 arcmin (90% c.l.).
  The burst had a peak flux of about 0.9 counts/cm2/s (20-200 keV, 1-s integration time) and a fluence in the same energy range of about 2e-7 erg/cm2.
  A plot of the light curve will be posted at http://ibas.iasf-milano.inaf.it/IBAS_Results.html
• GCN NOTICE
  

  TITLE:          GCN/INTEGRAL NOTICE
  NOTICE_DATE:    Mon 08 Feb 21 14:31:25 UT
  NOTICE_TYPE:    INTEGRAL Offline
  TRIGGER_NUM:    8970,   Sub_Num: 2
  GRB_RA:         260.1975d {+17h 20m 47s} (J2000),
                  260.4940d {+17h 21m 59s} (current),
                  259.4956d {+17h 17m 59s} (1950)
  GRB_DEC:        -12.6667d {-12d 40' 00"} (J2000),
                  -12.6864d {-12d 41' 10"} (current),
                  -12.6176d {-12d 37' 02"} (1950)
  GRB_ERROR:      2.00 [arcmin, radius, statistical only]
  GRB_INTEN:      16.39 [sigma]
  GRB_TIME:       48748.63 SOD {13:32:28.63} UT
  GRB_DATE:       19253 TJD;    39 DOY;   21/02/08
  SC_RA:          262.70 [deg] (J2000)
  SC_DEC:         -10.30 [deg] (J2000)
  SUN_POSTN:      322.46d {+21h 29m 51s}  -14.80d {-14d 47' 42"}
  SUN_DIST:        60.04 [deg]   Sun_angle= 4.1 [hr] (West of Sun)
  MOON_POSTN:     281.25d {+18h 44m 59s}  -25.04d {-25d 02' 30"}
  MOON_DIST:       23.15 [deg]
  GAL_COORDS:      10.78, 13.57 [deg] galactic lon,lat of the burst
  ECL_COORDS:     260.28, 10.44 [deg] ecliptic lon,lat of the burst
  COMMENTS:       INTEGRAL GRB Coordinates.  
  COMMENTS:       Time_Scale=5.0000 and Time_Error=5.0000.  
  COMMENTS:       There is a bright star (mag=4.42) 6.61 arcmin from this position.  
  COMMENTS:       refined_coordinates_after_offline_analysis
  

• GCN Circular #29439
  Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga), R. Fernandez-Munoz (IHSM/UMA-CSIC) and M. Jelinek (ASU-CAS), on behalf of a larger collaboration, report:
  Following the detection of GRB 210208A by INTEGRAL (Mereghetti et al. GCNC 29429), the 60 cm BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain) pointed to the position of the GRB, 17 deg away from the Galactic Center. No new source within the INTEGRAL/IBIS error box down to 17.3 mag is detected in the co-added image (2x60 s exposures, clear filter) obtained through a partially cloudy sky, at 06:17 UT on Feb 9 (~17.25 hr after trigger).
  We thank the staff at La Mayora for their excellent support.
• GCN Circular #29451
  H. Kumar(IITB), S. Joharle(Fergusson College), J. Stanzin (IAO), V. Bhalerao(IITB), G. C. Anupama(IIA), S. Barway(IIA) report on behalf of the GIT team:
  We observed GRB 210208A detected by INTEGRAL (S. Mereghetti et. al., GCN #29429) with 0.7m GROWTH-India Telescope (GIT). We obtained four exposures of 300-sec each in the r' filter. We did not detect any new source in our stacked image within the 2 arcmin circle around R.A.= 260.1976 deg, DEC.= -12.6667 deg. The obtained upper limit follows as:
  -----------------------------------------------------------------
  JD (mid) | T_mid-T0(hrs) | Exposure | Filter | Lim_mag (5-sigma) |
  -----------------------------------------------------------------
  2459254.51368 | 10.78 | 300*4 (stacked) | r' | > 21.1 |
  -----------------------------------------------------------------
  The magnitudes are calibrated against PanSTARRS (Flewelling et al., 2018) and not corrected for galactic extinction.
  The GROWTH India Telescope (GIT) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA).
• GCN Circular #29518
  Rahul Gupta, A. Kumar, Dimple, A. Ghosh, A. Aryan, B. Kumar, S. B. Pandey, and K. Misra (ARIES) report:
  We observed the field of INTEGRAL detected GRB 210208A (Mereghetti et al., GCN 29429) with 1.3m Devasthal Fast Optical Telescope (DFOT) located at Devasthal observatory of Aryabhatta Research Institute of Observational Sciences (ARIES), India. The observations were started on 2021-02-13 at 22:43:42 UT i.e. ~ 5.4 days after the INTEGRAL trigger. We have taken multiple frames having an exposure time of 180 s in the R filter. We did not detect any optical afterglow candidate in our single or stacked image within the INTEGRAL uncertainty circle (Mereghetti et al., GCN 29429). Our non-detection is consistent with Hu et al., GCN 29439 and Kumar et al., GCN 29451.
  We obtain the following 3-sigma upper limit in the stacked image.

  Date Start_UT T_start-T0 (days) Filter  Exp time (s)  Limiting Magnitude
  
  ======================================================
  2021-02-13 22:43:42   ~5.4          R   180*10      > 22.0
  

  The magnitude is not corrected for the Galactic extinction in the direction of the burst. Photometric calibration is performed using the standard stars from the USNO-B1.0 catalogue.
  This circular may be cited.