Gamma-ray Burst 220708A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 04:40:04 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1115156,   Seg_Num: 0
GRB_RA:          103.118d {+06h 52m 28s} (J2000),
                 103.786d {+06h 55m 09s} (current),
                 101.630d {+06h 46m 31s} (1950)
GRB_DEC:         +72.191d {+72d 11' 28"} (J2000),
                 +72.162d {+72d 09' 43"} (current),
                 +72.251d {+72d 15' 03"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       6292 [cnts]    Image_Peak=216 [image_cnts]
TRIGGER_DUR:     2.048 [sec] 
TRIGGER_INDEX:   443     E_range: 15-50 keV
BKG_INTEN:       63024 [cnts]
BKG_TIME:        16738.54 SOD {04:38:58.54} UT
BKG_DUR:         24 [sec]
GRB_DATE:        19768 TJD;   189 DOY;   22/07/08
GRB_TIME:        16769.83 SOD {04:39:29.83} UT
GRB_PHI:         -136.26 [deg]
GRB_THETA:        25.42 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.53 [sigma]
IMAGE_SIGNIF:    7.34 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +1  -3  +0  +0 -64  +0 
SUN_POSTN:       107.39d {+07h 09m 33s}  +22.47d {+22d 28' 24"}
SUN_DIST:         49.73 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.16d {+13h 52m 39s}   -9.71d {-09d 42' 26"}
MOON_DIST:       103.62 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.79, 25.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       96.08, 49.03 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 1.54,-4.97 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 04:42:52 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1115156,   Seg_Num: 0
GRB_RA:          103.118d {+06h 52m 28s} (J2000),
                 103.786d {+06h 55m 09s} (current),
                 101.630d {+06h 46m 31s} (1950)
GRB_DEC:         +72.191d {+72d 11' 28"} (J2000),
                 +72.162d {+72d 09' 43"} (current),
                 +72.251d {+72d 15' 03"} (1950)
GRB_DATE:        19768 TJD;   189 DOY;   22/07/08
GRB_TIME:        16769.83 SOD {04:39:29.83} UT
TRIGGER_INDEX:   443
GRB_PHI:         -136.26 [deg]
GRB_THETA:        25.42 [deg]
DELTA_TIME:      71.00 [sec]
TRIGGER_DUR:     2.048 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.53 [sigma]
IMAGE_SIGNIF:    7.34 [sigma]
LC_URL:          sw01115156000msb.lc
SUN_POSTN:       107.39d {+07h 09m 33s}  +22.47d {+22d 28' 23"}
SUN_DIST:         49.73 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.18d {+13h 52m 44s}   -9.72d {-09d 43' 07"}
MOON_DIST:       103.64 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.79, 25.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       96.08, 49.03 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 1.54,-4.97 [deg].

GCN Circular #32343
V. D'Elia (SSDC & INAF-OAR), A. D'Ai (INAF-IASFPA), T. Sakamoto (AGU) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 04:39:29 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220708A (trigger=1115156). Swift did not slew immediately to the burst. The BAT on-board calculated location is RA, Dec 103.118, +72.191 which is
```
   RA(J2000) = 06h 52m 28s
   Dec(J2000) = +72d 11' 28"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed several peaks with a duration of about 40 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~2 sec after the trigger.
Due to an observing constraint, Swift will not slew until T0+36.8 minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is V. D'Elia (valerio.delia AT ssdc.asi.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 05:20:54 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     1115156,   Seg_Num: 0
POINT_RA:        103.085d {+06h 52m 20s} (J2000)
POINT_DEC:       +72.167d {+72d 10' 01"} (J2000)
IMG_START_DATE:  19768 TJD;   189 DOY;   22/07/08
IMG_START_TIME:  19239.07 SOD {05:20:39.07} UT,   2469.2 [sec] since BAT Trigger Time
COUNTS:          2    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 05:26:45 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1115156,   Seg_Num: 0
POINT_RA:        103.086d {+06h 52m 21s} (J2000)
POINT_DEC:       +72.166d {+72d 09' 59"} (J2000)
POINT_ROLL:      174.831d
IMG_START_DATE:  19768 TJD;   189 DOY;   22/07/08
IMG_START_TIME:  19242.39 SOD {05:20:42.39} UT,   2472.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.832
N_STARS:         31
X_OFFSET:        287 [pixels]
Y_OFFSET:        569 [pixels]
X_MAX:           1246 [pixels]
Y_MAX:           1528 [pixels]
DET_THRESH:      26
PHOTO_THRESH:    16
SL_URL:          sw01115156000msufc2472.fits
SUN_POSTN:       107.42d {+07h 09m 41s}  +22.47d {+22d 28' 11"}
SUN_DIST:         49.71 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.57d {+13h 54m 16s}   -9.90d {-09d 53' 50"}
MOON_DIST:       103.94 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.82, 25.80 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       96.07, 49.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 05:27:04 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1115156,   Seg_Num: 0
POINT_RA:        103.086d {+06h 52m 21s} (J2000)
POINT_DEC:       +72.166d {+72d 09' 59"} (J2000)
POINT_ROLL:      174.831d
IMG_START_DATE:  19768 TJD;   189 DOY;   22/07/08
IMG_START_TIME:  19242.39 SOD {05:20:42.39} UT,   2472.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.832
N_STARS:         31
X_OFFSET:        287 [pixels]
Y_OFFSET:        569 [pixels]
X_MAX:           1246 [pixels]
Y_MAX:           1528 [pixels]
DET_THRESH:      26
PHOTO_THRESH:    16
SL_URL:          sw01115156000msufc2472.fits
SUN_POSTN:       107.42d {+07h 09m 41s}  +22.47d {+22d 28' 11"}
SUN_DIST:         49.71 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.57d {+13h 54m 16s}   -9.90d {-09d 53' 55"}
MOON_DIST:       103.94 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.82, 25.80 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       96.07, 49.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 05:28:29 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1115156,   Seg_Num: 0
POINT_RA:        103.086d {+06h 52m 21s} (J2000)
POINT_DEC:       +72.166d {+72d 09' 59"} (J2000)
ROLL:            174.831d
IMG_START_DATE:  19768 TJD;   189 DOY;   22/07/08
IMG_START_TIME:  19242.39 SOD {05:20:42.39} UT,   2472.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     678950471
X_OFFSET:        606 [pixels]
Y_OFFSET:        888 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       766
Y_GRB_POS:       1048
BINNING_INDEX:   1
IM_URL:          sw01115156000msuni2502.fits
SUN_POSTN:       107.42d {+07h 09m 41s}  +22.47d {+22d 28' 10"}
SUN_DIST:         49.71 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.58d {+13h 54m 19s}   -9.90d {-09d 54' 15"}
MOON_DIST:       103.95 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.82, 25.80 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       96.07, 49.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 08 Jul 22 05:28:42 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1115156,   Seg_Num: 0
POINT_RA:        103.086d {+06h 52m 21s} (J2000)
POINT_DEC:       +72.166d {+72d 09' 59"} (J2000)
ROLL:            174.831d
IMG_START_DATE:  19768 TJD;   189 DOY;   22/07/08
IMG_START_TIME:  19242.39 SOD {05:20:42.39} UT,   2472.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     678950471
X_OFFSET:        606 [pixels]
Y_OFFSET:        888 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       766
Y_GRB_POS:       1048
BINNING_INDEX:   1
IM_URL:          sw01115156000msuni2502.fits
SUN_POSTN:       107.42d {+07h 09m 41s}  +22.47d {+22d 28' 10"}
SUN_DIST:         49.71 [deg]   Sun_angle= 0.2 [hr] (West of Sun)
MOON_POSTN:      208.58d {+13h 54m 20s}   -9.91d {-09d 54' 19"}
MOON_DIST:       103.95 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      142.82, 25.80 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       96.07, 49.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #32344
M. Perri (SSDC & INAF-OAR), G. Tagliaferri (INAF-OAB), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU) and J.A. Kennea (PSU) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 220708A at 05:20:39.0 UT, 2469.3 seconds after the BAT trigger. No source was detected in 767 s of promptly downlinked data, which covered 94% of the BAT error circle. We are waiting for the full dataset to detect and localise the XRT counterpart.
GCN Circular #32347
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 1178 s of XRT Photon Counting mode data and 2 UVOT images for GRB 220708A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 103.12570, +72.14111 which is equivalent to:
```
RA (J2000): 06h 52m 30.17s
Dec (J2000): +72d 08' 28.0"
```
with an uncertainty of 2.6 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #32349
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar and I. Carrasco (UMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:
Following the detection of GRB 220708A by Swift (D'Elia et al. GCNC 32343), the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) observed the GRB location starting on Jul 08, 04:40:14 UT (~ 45 s after trigger). In the early co-added image (30 x 10 s exposures in the clear filter), no optical afterglow is detected within the enhanced Swift/XRT error region (Osborne et al. GCNC 32347) down to 20.5 mag.
We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.
GCN Circular #32352
A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , B. Sbarufatti (PSU), D.N. Burrows (PSU), and V. D'Elia report on behalf of the Swift-XRT team:
We have analysed 6.3 ks of XRT data for GRB 220708A (D'Elia et al. GCN Circ. 32343), from 2.5 ks to 49.4 ks after the BAT trigger. The data comprise 257 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 32347).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.1 (+nan, -nan).
If the light curve continues to decay with a power-law decay index of 1.1, the count rate at T+24 hours will be 8.8 x 10^-4 count s^-1
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01115156.
This circular is an official product of the Swift-XRT team.
GCN Circular #32354
A. Belles (PSU) and V. D'Elia (SSDC & INAF-OAR) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220708A 2473 s after the BAT trigger (D'Elia et al., GCN Circ. 32343). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 32347) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC          2473         2622          147         >19.8
white             2473         8325          402         >20.2
v                 2934         3134          197         >18.9
b                 2680         3954          216         >20.1
u                 2655         3749          216         >19.9
w1                2630         3544          216         >19.3
m2                3139         3339          197         >19.3
w2                2730         2930          197         >19.5
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.169 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #32361
S. D. Barthelmy (GSFC), D'Elia (SSDC & INAF-OAR), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+1566 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220708A (trigger #1115156) (D'Elia, et al., GCN Circ. 32343). The BAT ground-calculated position is RA, Dec = 103.038, 72.199 deg which is
```
    RA(J2000)  =  06h 52m 09.1s
    Dec(J2000) = +72d 11' 57.4"
```
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 75%.
The BAT mask-weighted light curve shows a peak starting from T-1 s to T+3 s. T90 (15-350 keV) is 4.4 +- 1.0 sec (estimated error including systematics).
The time-averaged spectrum from T-1.55 to T+3.44 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.31 +- 0.32. The fluence in the 15-150 keV band is 1.3 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+1.54 sec in the 15-150 keV band is 0.8 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/1115156/BA/

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Jochen Greiner, last update: 10-Jul-2022 [Disclaimer]