Gamma-ray Burst 220806A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 06 Aug 22 18:08:54 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1119268,   Seg_Num: 0
GRB_RA:          260.873d {+17h 23m 30s} (J2000),
                 261.224d {+17h 24m 54s} (current),
                 260.099d {+17h 20m 24s} (1950)
GRB_DEC:         -26.023d {-26d 01' 22"} (J2000),
                 -26.043d {-26d 02' 32"} (current),
                 -25.977d {-25d 58' 36"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3922 [cnts]    Image_Peak=239 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   137     E_range: 15-50 keV
BKG_INTEN:       24076 [cnts]
BKG_TIME:        65306.36 SOD {18:08:26.36} UT
BKG_DUR:         8 [sec]
GRB_DATE:        19797 TJD;   218 DOY;   22/08/06
GRB_TIME:        65319.80 SOD {18:08:39.80} UT
GRB_PHI:         -48.91 [deg]
GRB_THETA:         5.67 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     14.17 [sigma]
IMAGE_SIGNIF:    9.93 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +1  +0  -5  +1 +60  +0 
SUN_POSTN:       136.73d {+09h 06m 56s}  +16.55d {+16d 32' 52"}
SUN_DIST:        127.79 [deg]   Sun_angle= -8.3 [hr] (East of Sun)
MOON_POSTN:      238.49d {+15h 53m 58s}  -21.56d {-21d 33' 36"}
MOON_DIST:        21.25 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      359.80,  5.70 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      261.80, -2.84 [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 = 74.75,-5.53 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 06 Aug 22 18:12:30 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1119268,   Seg_Num: 0
GRB_RA:          260.873d {+17h 23m 30s} (J2000),
                 261.224d {+17h 24m 54s} (current),
                 260.099d {+17h 20m 24s} (1950)
GRB_DEC:         -26.023d {-26d 01' 22"} (J2000),
                 -26.043d {-26d 02' 32"} (current),
                 -25.977d {-25d 58' 36"} (1950)
GRB_DATE:        19797 TJD;   218 DOY;   22/08/06
GRB_TIME:        65319.80 SOD {18:08:39.80} UT
TRIGGER_INDEX:   137
GRB_PHI:         -48.91 [deg]
GRB_THETA:         5.67 [deg]
DELTA_TIME:      -63.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     14.17 [sigma]
IMAGE_SIGNIF:    9.93 [sigma]
LC_URL:          sw01119268000msb.lc
SUN_POSTN:       136.73d {+09h 06m 56s}  +16.55d {+16d 32' 49"}
SUN_DIST:        127.79 [deg]   Sun_angle= -8.3 [hr] (East of Sun)
MOON_POSTN:      238.53d {+15h 54m 06s}  -21.57d {-21d 34' 13"}
MOON_DIST:        21.21 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      359.80,  5.70 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      261.80, -2.84 [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 = 74.75,-5.53 [deg].

GCN Circular #32444
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) was pointed to the Swift GRB220806.76 (trigger No 1119268,17h 23m 29.52s , -26d 01m 22.8s, R=0.05) errorbox 30 sec after notice time and 47 sec after trigger time at 2022-08-06 18:09:26 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 13 deg. The sun altitude is -26.5 deg.
The galactic latitude b = 5 deg., longitude l = 0 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2051076
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

      52 |         MASTER-SAAO |   C |    10 | 16.7 |        
      73 |         MASTER-SAAO |   C |    10 | 16.7 |        
     101 |         MASTER-SAAO |   C |    20 | 16.8 |        
     134 |         MASTER-SAAO |   C |    20 | 16.8 |        
     171 |         MASTER-SAAO |   C |    30 | 17.0 |        
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #32445
K. L. Page (U Leicester), J.D. Gropp (PSU), S. Laha (GSFC/UMBC), D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team:
At 18:08:39 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220806A (trigger=1119268). Swift could not slew to the burst location due to a Moon constraint. The BAT on-board calculated location is RA, Dec 260.873, -26.023 which is
```
   RA(J2000) = 17h 23m 30s
   Dec(J2000) = -26d 01' 22"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak structure with a duration of about 5 sec. The peak count rate was ~1700 counts/sec (15-350 keV), at ~0 sec after the trigger.
Due to a Moon observing constraint, Swift cannot slew to the BAT position until 18:30 UT on 2022 August 09. There will thus be no XRT or UVOT data for this trigger before this time.
Burst Advocate for this burst is K. L. Page (kimlpage1978 AT gmail.com). 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 Circular #32453
D. M. Palmer (LANL),S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), 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+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220806A (trigger #1119268) (Page et al., GCN Circ. 32445). The BAT ground-calculated position is RA, Dec = 260.858, -26.021 deg which is
```
   RA(J2000)  =  17h 23m 26.0s
   Dec(J2000) = -26d 01' 15.2"
```
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The BAT light curve showed a single peaked structure with a duration of about 6 sec. T90 (15-350 keV) is 4.78 +- 2.00 sec (estimated error including systematics).
The time-averaged spectrum from T-0.30 to T+6.66 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.81 +- 0.33. The fluence in the 15-150 keV band is 1.5 +- 0.3 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+0.76 sec in the 15-150 keV band is 1.1 +- 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/1119268/BA/

Back to JG's homepage

Jochen Greiner, last update: 09-Aug-2022 [Disclaimer]