Gamma-ray Burst 220617A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 17 Jun 22 18:31:42 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     677183477
GRB_RA:          157.450d {+10h 29m 48s} (J2000),
                 157.774d {+10h 31m 06s} (current),
                 156.727d {+10h 26m 54s} (1950)
GRB_DEC:         +37.233d {+37d 13' 60"} (J2000),
                 +37.118d {+37d 07' 04"} (current),
                 +37.490d {+37d 29' 23"} (1950)
GRB_ERROR:       5.98 [deg radius, statistical plus systematic]
GRB_INTEN:       612 [cnts/sec]
DATA_SIGNIF:     20.30 [sigma]
INTEG_TIME:      0.512 [sec]
GRB_DATE:        19747 TJD;   168 DOY;   22/06/17
GRB_TIME:        66672.90 SOD {18:31:12.90} UT
GRB_PHI:          72.00 [deg]
GRB_THETA:        25.00 [deg]
DATA_TIME_SCALE: 0.5120 [sec]
HARD_RATIO:      0.37
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       1,0,1, 0,0,0, 0,0,0, 1,0,0, 0,0,
SUN_POSTN:        86.24d {+05h 44m 58s}  +23.39d {+23d 23' 27"}
SUN_DIST:         61.87 [deg]   Sun_angle= -4.8 [hr] (East of Sun)
MOON_POSTN:      316.85d {+21h 07m 24s}  -21.83d {-21d 49' 55"}
MOON_DIST:       156.32 [deg]
MOON_ILLUM:      85 [%]
GAL_COORDS:      185.19, 58.59 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      144.69, 25.70 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_lc_medres34_bn220617772.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 18.48,16.37 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 17 Jun 22 18:32:00 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      59
TRIGGER_NUM:     677183477
GRB_RA:          155.450d {+10h 21m 48s} (J2000),
                 155.756d {+10h 23m 01s} (current),
                 154.768d {+10h 19m 04s} (1950)
GRB_DEC:         +19.200d {+19d 11' 60"} (J2000),
                 +19.086d {+19d 05' 10"} (current),
                 +19.453d {+19d 27' 09"} (1950)
GRB_ERROR:       2.39 [deg radius, statistical only]
DATA_SIGNIF:     20.60 [sigma]
DATA_INTERVAL:   0.512 [sec]
GRB_DATE:        19747 TJD;   168 DOY;   22/06/17
GRB_TIME:        66672.90 SOD {18:31:12.90} UT
GRB_PHI:          76.00 [deg]
GRB_THETA:        43.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4173 (Gnd S/W Version number)
SUN_POSTN:        86.24d {+05h 44m 59s}  +23.39d {+23d 23' 27"}
SUN_DIST:         64.32 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      316.85d {+21h 07m 25s}  -21.83d {-21d 49' 52"}
MOON_DIST:       162.09 [deg]
MOON_ILLUM:      85 [%]
GAL_COORDS:      217.85, 54.84 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      150.26,  8.37 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_lc_medres34_bn220617772.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_677183477.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        Bright hard burst in the GBM.  
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(1.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=9958).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 17 Jun 22 18:40:41 UT
NOTICE_TYPE:     Fermi-GBM Final Position
RECORD_NUM:      0
TRIGGER_NUM:     677183477
GRB_RA:          155.830d {+10h 23m 19s} (J2000),
                 156.137d {+10h 24m 33s} (current),
                 155.144d {+10h 20m 35s} (1950)
GRB_DEC:         +21.160d {+21d 09' 36"} (J2000),
                 +21.046d {+21d 02' 45"} (current),
                 +21.413d {+21d 24' 48"} (1950)
GRB_ERROR:       2.68 [deg radius, statistical only]
GRB_DATE:        19747 TJD;   168 DOY;   22/06/17
GRB_TIME:        66672.90 SOD {18:31:12.90} UT
GRB_PHI:          76.00 [deg]
GRB_THETA:        41.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41731 (Gnd S/W Version number)
SUN_POSTN:        86.25d {+05h 45m 00s}  +23.39d {+23d 23' 27"}
SUN_DIST:         64.08 [deg]   Sun_angle= -4.7 [hr] (East of Sun)
MOON_POSTN:      316.94d {+21h 07m 47s}  -21.81d {-21d 48' 24"}
MOON_DIST:       162.13 [deg]
MOON_ILLUM:      85 [%]
GAL_COORDS:      214.79, 55.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      149.86, 10.33 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_lc_medres34_bn220617772.gif
LOC_URL:         http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_locplot_all_bn220617772.png
COMMENTS:        Fermi-GBM Final Position.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file should be available by the time this FINAL notice is produced.  
COMMENTS:        This notice was generated completely by automated pipeline processing.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        Bright hard burst in the GBM.  
COMMENTS:        This is likely a Short GRB.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(1.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=9958).

GCN Circular #32209
The Fermi GBM team reports the detection of a likely SHORT GRB
At 18:31:12 UT on 17 Jun 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220617A (trigger 677183477.902462 / 220617772).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 155.8, Dec = 21.2 (J2000 degrees, equivalent to J2000 10h 23m, 21d 11'), with a statistical uncertainty of 2.7 degrees.
The angle from the Fermi LAT boresight is 41.0 degrees.
The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_skymap_all_bn220617772.png
The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_healpix_all_bn220617772.fit
The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220617772/quicklook/glg_lc_medres34_bn220617772.gif
GCN Circular #32210
V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)
MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 220617A ( Fermi GBM team, GCN 32209) errorbox 565 sec after notice time and 600 sec after trigger time at 2022-06-17 18:41:13 UT, with upper limit up to 17.8 mag. The observations began at zenith distance = 72 deg. The sun altitude is -37.2 deg.
The galactic latitude b = 56 deg., longitude l = 216 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2008774
We obtain a following upper limits.
```
Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

     661 | 2022-06-17 18:41:13 |         MASTER-SAAO | (10h 22m 17.52s , +21d 18m 28.6s) |   C |   120 | 16.9 |        
     826 | 2022-06-17 18:41:13 |         MASTER-SAAO | (10h 22m 18.15s , +21d 18m 33.0s) |   C |   450 | 17.8 |  Coadd 
     843 | 2022-06-17 18:44:01 |         MASTER-SAAO | (10h 22m 23.41s , +21d 20m 08.9s) |   C |   150 | 17.2 |        
    1040 | 2022-06-17 18:47:02 |         MASTER-SAAO | (10h 22m 18.64s , +21d 19m 26.5s) |   C |   180 | 17.1 |        
    1914 | 2022-06-17 19:02:36 |         MASTER-SAAO | (10h 18m 16.82s , +22d 17m 11.7s) |   C |    60 | 15.8 |        
    2005 | 2022-06-17 19:04:08 |         MASTER-SAAO | (10h 26m 56.39s , +22d 16m 07.7s) |   C |    60 | 16.2 |        
    2093 | 2022-06-17 19:05:35 |         MASTER-SAAO | (10h 10m 34.70s , +20d 21m 52.6s) |   C |    60 | 14.0 |        
    2184 | 2022-06-17 19:07:06 |         MASTER-SAAO | (10h 18m 58.19s , +20d 23m 01.3s) |   C |    60 | 16.0 |        
    2884 | 2022-06-17 19:18:46 |         MASTER-SAAO | (10h 26m 42.09s , +20d 21m 46.5s) |   C |    60 | 14.8 |        
    2976 | 2022-06-17 19:20:18 |         MASTER-SAAO | (10h 35m 11.11s , +20d 23m 25.2s) |   C |    60 | 16.1 |        
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 17 Jun 22 23:37:26 UT
NOTICE_TYPE:     Fermi-LAT Offline Position
TRIGGER_NUM:     220617772
GRB_RA:          156.960d {+10h 27m 50s} (J2000),
                 157.261d {+10h 29m 03s} (current),
                 156.289d {+10h 25m 09s} (1950)
GRB_DEC:         +15.530d {+15d 31' 48"} (J2000),
                 +15.415d {+15d 24' 53"} (current),
                 +15.785d {+15d 47' 08"} (1950)
GRB_ERROR:       5.39 [arcmin radius, 90% containment, statistical only]
GRB_DATE:        19747 TJD;   168 DOY;   22/06/17
GRB_TIME:        66672.89 SOD {18:31:12.89} UT
TRIGGER_ID:      0x20000000
MISC:            0x40000000
SUN_POSTN:        86.46d {+05h 45m 51s}  +23.40d {+23d 23' 45"}
SUN_DIST:         66.64 [deg]   Sun_angle= -4.7 [hr] (East of Sun)
MOON_POSTN:      320.04d {+21h 20m 10s}  -20.95d {-20d 57' 02"}
MOON_DIST:       162.74 [deg]
MOON_ILLUM:      83 [%]
GAL_COORDS:      224.69, 54.76 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      152.96,  5.49 [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.  
COMMENTS:        This source corresponds to GBM trigger.

GCN Circular #32211
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Fermi/LAT GRB 220617B. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021505
Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Fermi/LAT event. Any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular #32212
N. Di Lalla (Stanford Univ.), M. Arimoto (Kanazawa Univ.), M. Axelsson (KTH & Stockholm Univ.) and G. Principe (University and INFN Trieste) report on behalf of the Fermi-LAT team:
On June 17, 2022, Fermi-LAT detected high-energy emission from GRB 220617A, which was also detected by Fermi-GBM (trigger 677183477 / 220617772, GCN 32209).
The best LAT on-ground location is found to be
RA, Dec = 156.96, 15.53 (degrees, J2000)
with an error radius of 0.09 deg (90 % containment, statistical error only). This was 46 deg from the LAT boresight at the time of the GBM trigger:
T0 = 18:31:12 UT.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the GBM emission with high significance. The photon flux above 100 MeV in the time interval 0-200 s after the GBM trigger is (4.9 +/- 0.8)E-05 ph/cm2/s.
The estimated photon index above 100 MeV is -1.9 +/- 0.1.
The highest-energy photon is a 8.2 GeV event which is observed 0.9 seconds after the GBM trigger.
A Swift ToO has been approved for this burst.
The Fermi-LAT point of contact for this burst is Giacomo Principe (giacomo.principe@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 #32215
K.L. Page (U. Leicester), M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), A.P. Beardmore (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the Fermi/LAT-detected burst GRB 220617A (Di Lalla et al. GCN Circ. 32212), collecting 4.9 ks of Photon Counting (PC) mode data between T0+23.9 ks and T0+37.1 ks.
Five uncatalogued X-ray sources have been detected, however none of them is above the RASS limit or shows definitive signs of fading. Therefore, at the present time we cannot identify which, if any, is the afterglow. Details of these sources are given below.
Please note: due to an error, the original GCN announcing these Swift observations (GCN 32211) referred to "GRB 220617B", whereas the observations were of GRB 220617A.
Source 1:
```
  RA (J2000.0):  157.1531  =  10:28:36.74
  Dec (J2000.0): +15.4493  =  +15:26:57.6
  Error: 6.4 arcsec (radius, 90% conf.)
  Count-rate: (2.7 [+1.5, -1.1])e-3 ct s^-1   
  Distance: 730 arcsec from Fermi/LAT position.
  Flux: (5.5 [+3.0, -2.2])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)
```
Source 2:
```
  RA (J2000.0):  156.9298  =  10:27:43.15
  Dec (J2000.0): +15.4059  =  +15:24:21.1
  Error: 6.4 arcsec (radius, 90% conf.)
  Count-rate: (1.45 [+0.92, -0.65])e-3 ct s^-1	 
  Distance: 458 arcsec from Fermi/LAT position.
```
Source 3:
```
  RA (J2000.0):  157.0400  =  10:28:9.60
  Dec (J2000.0): +15.4886  =  +15:29:19.1
  Error: 6.4 arcsec (radius, 90% conf.)
  Count-rate: (1.67 [+0.91, -0.69])e-3 ct s^-1	 
  Distance: 314 arcsec from Fermi/LAT position.
```
Source 4:
```
  RA (J2000.0):  156.9896  =  10:27:57.50
  Dec (J2000.0): +15.4454  =  +15:26:43.4
  Error: 5.7 arcsec (radius, 90% conf.)
  Count-rate: (1.75 [+0.93, -0.70])e-3 ct s^-1	 
  Distance: 321 arcsec from Fermi/LAT position.
```
Source 5:
```
  RA (J2000.0):  156.8566  =  10:27:25.60
  Dec (J2000.0): +15.3577  =  +15:21:27.8
  Error: 6.3 arcsec (radius, 90% conf.)
  Count-rate: 0.0114 [+0.0046, -0.0036] ct s^-1   
  Distance: 716 arcsec from Fermi/LAT position.
```
The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/ToO_GRBs/00021505.
This circular is an official product of the Swift-XRT team.
GCN Circular #32220
A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin on behalf of the HEND/Mars-Odyssey team,
A. Ridnaia, D. Frederiks, D. Svinkin, A. Lysenko, and T. Cline on behalf of the Konus-Wind team,
A. Goldstein, M. S. Briggs, and C. Wilson-Hodge on behalf of the Fermi GBM team,
E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
and
W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr, and A.S. Gardner on on behalf of the GRS-Odyssey GRB team, report:
The short-duration GRB 220617A (Fermi-GBM detection: Fermi GBM Team, GCN Circ 32209; Fermi-LAT detection: Di Lalla et al., GCN Circ 32212) has been detected by Fermi (GBM trigger 677183477), INTEGRAL (SPI-ACS), Konus-Wind, and Mars-Odyssey (HEND), so far, at about 66669 s UT (18:31:09).
We have triangulated it to a preliminary, 3 sigma error box whose coordinates are:
```
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  156.882 (10h 27m 32s) +15.600 (+15d 36' 01")
 Corners:
  157.351 (10h 29m 24s) +16.445 (+16d 26' 41")
  157.423 (10h 29m 41s) +16.807 (+16d 48' 25")
  156.369 (10h 25m 29s) +14.606 (+14d 36' 21")
  156.247 (10h 24m 59s) +14.082 (+14d 04' 54")
 ---------------------------------------------
```
The error box area is 867 sq. arcmin, and its maximum dimension is 2.9 deg (the minimum one is 5.8 arcmin). The Sun distance was 66 deg.
This box may be improved.
A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB220617_T66669/IPN
The Fermi-LAT localization was covered by Swift ToO (GCN Circ 32215) but none of the X-ray sources detected are inside the box.
The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.
GCN Circular #32224
J. Wood (NASA/MSFC) reports on behalf of the Fermi GBM Team:
"At 18:31:12.89 UT on 17 June 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220617A (trigger 677183477 / 220617772). which was also detected by the Fermi-LAT (N. Di Lalla et al. 2022, GCN 32212).
The Fermi GBM Final Real-time Localization (GCN 32209) is consistent with the LAT position.
The GBM light curve consists of a single pulse with a duration (T90) of about 0.7 s (50-300 keV). The time-averaged spectrum from T0-0.1 s to T0+0.5 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.7 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 2.3 +/- 0.3 MeV.
The event fluence (10-1000 keV) in this time interval is (2.3 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured starting from T0+0.2 s in the 10-1000 keV band is 10 +/- 1 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular #32227
P. D'Avanzo (INAF-OAB), S. Piranomonte (INAF-OAR), S. Campana (INAF-OAB), V. D'Elia (ASI/SSDC), L. Di Fabrizio, A. Garcia De Gurtubai Escudero (INAF-TNG) on behalf of the CIBO collaboration report:
We observed the field of the short GRB 220617A (Fermi-GBM detection: Fermi GBM Team, GCN Circ 32209; Fermi-LAT detection: Di Lalla et al., GCN Circ 32212; IPN detection: Kozyrev et al., GCN Circ. 32220) with the Italian 3.6m TNG telescope equipped with the optical camera DOLORES. A series of images were obtained with the r-sdss filter on 2022-06-18 from 21:22:18 UT to 22:09:26 UT (i.e. at a mid time of about 1.14 days after the burst).
The pointing enabled to image the location of the Swift-XRT sources #3 and #4 (Page et al., GCN Circ. 32215), both consistent with the Fermi/LAT error circle.
No clear afterglow candidate is detected within the error circles of XRT sources #3 and #4 down to a typical limiting magnitude of r ~ 24.5 (AB; calibrated against the SDSS catalogue).
We note the presence of catalogued galaxies from the SDSS within the error circles of the XRT sources #3 and #4:
XRT3
```
- SDSS J102809.40+152924.9 (photo-z = 0.102 +/- 0.031)
- SDSS J102809.54+152915.8 (photo-z = 0.381 +/- 0.083)
```
XRT4
```
- SDSS J102757.23+152645.6 (photo-z = 0.714 +/- 0.116)
```
GCN Circular #32237
A.Ridnaia, D. Frederiks, A.Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report:
The short-duration GRB 220617A (Fermi-GBM detection: Fermi GBM Team, GCN Circ 32209; Wood, GCN Circ 32224; Fermi-LAT detection: Di Lalla et al., GCN Circ 32212; IPN triangulation: Kozyrev et al., GCN Circ 32220) triggered Konus-Wind at T0=66669.24 s UT (18:31:09.240).
The burst light curve shows a multipeaked structure, which starts at ~T0-0.2 s and has a total duration of ~0.5 s. The emission is seen up to ~10 MeV.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB220617_T66669/
As observed by Konus-Wind, the burst had a fluence of 6.53(-1.15,+1.34)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0-0.028 s, of 3.31(-1.27,+1.36)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = 0.02(-0.40,+0.57) and Ep = 1384(-341,+504) keV (chi2 = 34/40 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.0 (chi2 = 33/39 dof).
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.

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Jochen Greiner, last update: 20-Jun-2022 [Disclaimer]