Gamma-ray Burst 170409A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:42:24 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     513398525
GRB_RA:          342.900d {+22h 51m 36s} (J2000),
                 343.129d {+22h 52m 31s} (current),
                 342.236d {+22h 48m 57s} (1950)
GRB_DEC:         -15.400d {-15d 24' 00"} (J2000),
                 -15.308d {-15d 18' 28"} (current),
                 -15.666d {-15d 39' 55"} (1950)
GRB_ERROR:       19.70 [deg radius, statistical plus systematic]
GRB_INTEN:       152 [cnts/sec]
DATA_SIGNIF:     9.80 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          41.00 [deg]
GRB_THETA:        80.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.17
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   2%  Cyg X-1
DETECTORS:       1,0,0, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 36"}
SUN_DIST:         41.42 [deg]   Sun_angle= 2.3 [hr] (West of Sun)
MOON_POSTN:      175.92d {+11h 43m 41s}   +3.96d {+03d 57' 40"}
MOON_DIST:       163.05 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:       49.64,-59.82 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      338.35, -7.52 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 177.28,-22.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:42:33 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      58
TRIGGER_NUM:     513398525
GRB_RA:          357.033d {+23h 48m 08s} (J2000),
                 357.255d {+23h 49m 01s} (current),
                 356.390d {+23h 45m 34s} (1950)
GRB_DEC:         -10.067d {-10d 04' 00"} (J2000),
                  -9.971d {-09d 58' 13"} (current),
                 -10.345d {-10d 20' 40"} (1950)
GRB_ERROR:       14.13 [deg radius, statistical plus systematic]
GRB_INTEN:       154 [cnts/sec]
DATA_SIGNIF:     14.30 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          26.00 [deg]
GRB_THETA:        80.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.22
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   1%  Generic Transient
DETECTORS:       1,0,0, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 36"}
SUN_DIST:         27.09 [deg]   Sun_angle= 1.4 [hr] (West of Sun)
MOON_POSTN:      175.92d {+11h 43m 41s}   +3.96d {+03d 57' 39"}
MOON_DIST:       173.85 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:       78.76,-67.34 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      353.26, -8.05 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 177.28,-22.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:42:37 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      57
TRIGGER_NUM:     513398525
GRB_RA:            0.010d {+00h 00m 02s} (J2000),
                   0.231d {+00h 00m 55s} (current),
                 359.369d {+23h 57m 29s} (1950)
GRB_DEC:          -6.760d {-06d 45' 35"} (J2000),
                  -6.664d {-06d 39' 49"} (current),
                  -7.038d {-07d 02' 17"} (1950)
GRB_ERROR:       4.77 [deg radius, statistical only]
DATA_SIGNIF:     16.40 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          22.00 [deg]
GRB_THETA:        82.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 36"}
SUN_DIST:         22.72 [deg]   Sun_angle= 1.2 [hr] (West of Sun)
MOON_POSTN:      175.92d {+11h 43m 41s}   +3.96d {+03d 57' 38"}
MOON_DIST:       174.93 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:       89.67,-66.25 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      357.31, -6.20 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_513398525.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:42:53 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      68
TRIGGER_NUM:     513398525
GRB_RA:          335.733d {+22h 22m 56s} (J2000),
                 335.982d {+22h 23m 56s} (current),
                 335.011d {+22h 20m 03s} (1950)
GRB_DEC:         -35.150d {-35d 08' 59"} (J2000),
                 -35.062d {-35d 03' 43"} (current),
                 -35.403d {-35d 24' 10"} (1950)
GRB_ERROR:       6.43 [deg radius, statistical plus systematic]
GRB_INTEN:       431 [cnts/sec]
DATA_SIGNIF:     23.30 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          55.00 [deg]
GRB_THETA:        65.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      0.28
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      97%  GRB
2nd_MOST_LIKELY:   1%  Generic Transient
DETECTORS:       1,0,0, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 37"}
SUN_DIST:         58.19 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      175.92d {+11h 43m 42s}   +3.96d {+03d 57' 35"}
MOON_DIST:       143.83 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:        9.38,-57.43 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.21,-23.24 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 177.28,-22.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:43:02 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      89
TRIGGER_NUM:     513398525
GRB_RA:          335.850d {+22h 23m 24s} (J2000),
                 336.099d {+22h 24m 24s} (current),
                 335.127d {+22h 20m 31s} (1950)
GRB_DEC:         -35.350d {-35d 21' 00"} (J2000),
                 -35.262d {-35d 15' 43"} (current),
                 -35.603d {-35d 36' 11"} (1950)
GRB_ERROR:       4.22 [deg radius, statistical plus systematic]
GRB_INTEN:       1067 [cnts/sec]
DATA_SIGNIF:     110.10 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          55.00 [deg]
GRB_THETA:        65.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.32
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       1,0,0, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 37"}
SUN_DIST:         58.24 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      175.93d {+11h 43m 42s}   +3.96d {+03d 57' 34"}
MOON_DIST:       143.72 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:        9.00,-57.51 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.22,-23.46 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 177.28,-22.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:43:08 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      93
TRIGGER_NUM:     513398525
GRB_RA:          336.017d {+22h 24m 04s} (J2000),
                 336.266d {+22h 25m 04s} (current),
                 335.293d {+22h 21m 10s} (1950)
GRB_DEC:         -35.650d {-35d 38' 59"} (J2000),
                 -35.562d {-35d 33' 42"} (current),
                 -35.904d {-35d 54' 12"} (1950)
GRB_ERROR:       3.57 [deg radius, statistical plus systematic]
GRB_INTEN:       3265 [cnts/sec]
DATA_SIGNIF:     339.20 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          55.00 [deg]
GRB_THETA:        65.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.38
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       1,0,0, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 37"}
SUN_DIST:         58.32 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      175.93d {+11h 43m 42s}   +3.96d {+03d 57' 33"}
MOON_DIST:       143.55 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:        8.42,-57.62 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.23,-23.79 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 177.28,-22.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 02:44:03 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      2
TRIGGER_NUM:     513398525
GRB_RA:          359.570d {+23h 58m 17s} (J2000),
                 359.791d {+23h 59m 10s} (current),
                 358.929d {+23h 55m 43s} (1950)
GRB_DEC:         -13.570d {-13d 34' 11"} (J2000),
                 -13.474d {-13d 28' 25"} (current),
                 -13.848d {-13d 50' 53"} (1950)
GRB_ERROR:       4.22 [deg radius, statistical only]
DATA_SIGNIF:     15.00 [sigma]
DATA_INTERVAL:   13.312 [sec]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9720.49 SOD {02:42:00.49} UT
GRB_PHI:          25.00 [deg]
GRB_THETA:        76.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:        17.95d {+01h 11m 49s}   +7.61d {+07d 36' 38"}
SUN_DIST:         27.75 [deg]   Sun_angle= 1.2 [hr] (West of Sun)
MOON_POSTN:      175.93d {+11h 43m 44s}   +3.96d {+03d 57' 24"}
MOON_DIST:       169.75 [deg]
MOON_ILLUM:      95 [%]
GAL_COORDS:       77.82,-71.62 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      354.12,-12.26 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170409112/quicklook/glg_lc_medres34_bn170409112.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_513398525.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This is likely a Long GRB.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(24.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7805).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 09 Apr 17 15:38:04 UT
NOTICE_TYPE:     Fermi-LAT Offline Position
TRIGGER_NUM:     513398525 
GRB_RA:          347.530d {+23h 10m 07s} (J2000),
                 347.754d {+23h 11m 01s} (current),
                 346.881d {+23h 07m 32s} (1950)
GRB_DEC:          -7.160d {-07d 09' 35"} (J2000),
                  -7.066d {-07d 03' 57"} (current),
                  -7.431d {-07d 25' 52"} (1950)
GRB_ERROR:       8.99 [arcmin radius, 90% containment, statistical only]
GRB_DATE:        17852 TJD;    99 DOY;   17/04/09
GRB_TIME:        9719.49 SOD {02:41:59.49} UT
TRIGGER_ID:      0x20000000
MISC:            0x40000000
SUN_POSTN:        18.45d {+01h 13m 47s}   +7.81d {+07d 48' 36"}
SUN_DIST:         34.03 [deg]   Sun_angle= 2.0 [hr] (West of Sun)
MOON_POSTN:      182.37d {+12h 09m 28s}   +1.77d {+01d 46' 12"}  
MOON_DIST:       164.50 [deg] 
MOON_ILLUM:      97 [%] 
GAL_COORDS:       68.00,-58.76 [deg] galactic lon,lat of the burst (or transient)       
ECL_COORDS:      345.74, -1.67 [deg] ecliptic lon,lat of the burst (or transient)      
COMMENTS:        Fermi LAT Offline position.
COMMENTS:        This Notice was ground-generated -- not flight-generated.
COMMENTS:        It is the result of human-in-the-loop processing.
COMMENTS:        This is a human generated position of a LAT ground detection of GRB 170409A.    
COMMENTS:        This source corresponds to GBM trigger.

GCN Circular #21004
F. Longo (University and INFN, Trieste), J. L. Racusin (NASA/GSFC), and D. Kocesvki (NASA/MSFC)report on behalf of the Fermi-LAT team:
At 02:41:59.49 on April 9, 2017, Fermi-LAT detected high-energy emission from GRB 170904A, which was also detected by Fermi-GBM (trigger 513398525/170409112).
The best LAT on-ground location is found to be:
RA, Dec = 347.53, -7.16 (degrees, J2000)
with an error radius of 0.15 deg (90% containment, statistical error only). This was 82 deg from the LAT boresight at the time of the trigger and triggered an autonomous repoint of the spacecraft.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally consistent with the GBM emission. More than 14 photons above 100 MeV and 2 photons above 1 GeV are observed within 1000 seconds. The highest-energy photon is a 10 GeV event which is observed 442 seconds after the GBM trigger.
A Swift ToO has been requested for this burst.
The Fermi-LAT point of contact for this burst is Francesco Longo (francesco.longo@ts.infn.it).
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.
GCN Circular #21005
E. Burns (UAH), E. Bissaldi (Politecnico & INFN Bari), S. Poolakkil (UAH), and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 02:42:00.49 UT on 09 April 2017 , the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170409A (trigger 513398525/170409113) which was also detected by the Fermi LAT (Longo et al. 2017, GCN 21004). The GBM on-ground location is consistent with the LAT position.
The trigger resulted in an Autonomous Repoint Request (ARR) by the GBM Flight Software owing to the high peak flux of the GRB. This ARR was accepted and the spacecraft slewed to the GBM in-flight location. The initial angle from the Fermi LAT boresight to the LAT location is 82 degrees.
The GBM light curve shows multiple peaks with a duration (T90) of about 68 s (50-300 keV). The time-averaged spectrum from T0+26.880 s to T0+97.537 s is best fit by a Band function with Epeak = 1150 +/- 20 keV, alpha = -0.82 +/- 0.01, and beta = -2.84 +/- 0.06.
The event fluence (10-1000 keV) in this time interval is (2.956 +/- 0.009)E-04 erg/cm^2. The 1-sec peak photon flux measured starting from T0+38.0164 s in the 10-1000 keV band is 61.8 +/- 0.6 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #21007
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report:
The long, very bright GRB 170409A (Fermi-LAT detection: Longo et al., GCN 21004; Fermi-GBM detection: Burns et al., GCN 21005) triggered Konus-Wind at T0=3D9741.024 s UT (02:42:21.024)
The burst light curve shows multiple partially overlapped emission peaks in the interval from ~T0-29 s to ~T0+95 s. A possible precursor is seen as a weak count rate excess in the same KW detector at ~T0-143 s. The emission is seen up to ~10 MeV.
As observed by Konus-Wind, the burst had a fluence of (5.7 =B1 0.2)x10^-4 erg/cm2 and a 64-ms peak energy flux, measured from T0+12.982, of (1.00 =B1 0.06)x10^-4 erg/cm2 (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum (measured from T0 to T0+91.648 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha =3D -0.76 (-0.05,+0.05), the high energy photon index beta =3D -2.23 (-0.11,+0.09), the peak energy Ep =3D 808 (-65,+69) keV, chi2 =3D 111/95 dof.
The spectrum near the peak count rate (measured from T0+12.288 s to T0+13.056 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha =3D -0.60 (-0.06,+0.07), the high energy photon index beta =3D -3.52 (-6.48,+0.65), the peak energy Ep =3D 1671 (-180,+192) keV, chi2 =3D 99/77 dof.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB170409_T09741/
All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary.
GCN Circular #21008
Klotz A., Turpin D., Atteia J.L. (CNRS-OMP-IRAP), Boer, M., Laugier, R. (CNRS-ARTEMIS), Gendre B. (UVI - Etelman Obs.) Peyrot A., Teng J.P. (Les Makes Observatory, France), Thierry P. (Auragne Observatory, France), Klotz A.N.O. (Guitalens Observatory, France) report:
We imaged the field of GRB 170409A detected by Fermi LAT and GBM (trigger 513398525/170409112) with the TAROT robotic telescope (D=18cm) located at the Reunion observatory, France.
The GRB is located at 34 degrees from the sun and is observable only in the dawn light in the morning.
The observations started 0.95 day after the GRB trigger. We stacked 13 images of 120s and examined a field of view of 0.2 degree (radius) around the position provided by Longo et al. (GCNC 21004). We do not see any new source at the limiting magnitude of:
t0+0.95d to t0+0.96h : Rlim=17.0 +/- 0.2
Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction.

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Jochen Greiner, last update: 10-Apr-2017 [Disclaimer]