Gamma-ray Burst 200715A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Wed 15 Jul 20 23:52:15 UT
NOTICE_TYPE:    INTEGRAL Wakeup
TRIGGER_NUM:    8663,   Sub_Num: 1
GRB_RA:         248.6058d {+16h 34m 25s} (J2000),
                249.0045d {+16h 36m 01s} (current),
                247.6375d {+16h 30m 33s} (1950)
GRB_DEC:        -51.8071d {-51d 48' 24"} (J2000),
                -51.8484d {-51d 50' 53"} (current),
                -51.7033d {-51d 42' 11"} (1950)
GRB_ERROR:      3.23 [arcmin, radius, statistical only]
GRB_INTEN:      8.41 [sigma]
GRB_TIME:       85923.88 SOD {23:52:03.88} UT
GRB_DATE:       19045 TJD;   197 DOY;   20/07/15
SC_RA:          234.98 [deg] (J2000)
SC_DEC:         -56.61 [deg] (J2000)
SUN_POSTN:      115.81d {+07h 43m 15s}  +21.32d {+21d 19' 03"}
SUN_DIST:       132.83 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      55.54d {+03h 42m 10s}  +16.78d {+16d 47' 01"}
MOON_DIST:      143.35 [deg]
GAL_COORDS:     333.71, -2.79 [deg] galactic lon,lat of the burst
ECL_COORDS:     254.98,-29.48 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.  
COMMENTS:       Time_Scale=10.0000 and Time_Error=10.0000.  
COMMENTS:       Possibly real GRB event

red DSS finding chart ps-file

GCN NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Wed 15 Jul 20 23:55:13 UT
NOTICE_TYPE:    INTEGRAL Refined
TRIGGER_NUM:    8663,   Sub_Num: 2
GRB_RA:         248.5681d {+16h 34m 16s} (J2000),
                248.9669d {+16h 35m 52s} (current),
                247.5997d {+16h 30m 24s} (1950)
GRB_DEC:        -51.8228d {-51d 49' 21"} (J2000),
                -51.8642d {-51d 51' 50"} (current),
                -51.7189d {-51d 43' 07"} (1950)
GRB_ERROR:      2.70 [arcmin, radius, statistical only]
GRB_INTEN:      16.62 [sigma]
GRB_TIME:       85953.88 SOD {23:52:33.88} UT
GRB_DATE:       19045 TJD;   197 DOY;   20/07/15
SC_RA:          234.98 [deg] (J2000)
SC_DEC:         -56.61 [deg] (J2000)
SUN_POSTN:      115.81d {+07h 43m 15s}  +21.32d {+21d 19' 02"}
SUN_DIST:       132.80 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      55.57d {+03h 42m 16s}  +16.79d {+16d 47' 28"}
MOON_DIST:      143.35 [deg]
GAL_COORDS:     333.68, -2.78 [deg] galactic lon,lat of the burst
ECL_COORDS:     254.96,-29.50 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.  
COMMENTS:       Time_Scale=50.0000 and Time_Error=50.0000.  
COMMENTS:       Possibly real GRB event

GCN NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Thu 16 Jul 20 01:14:40 UT
NOTICE_TYPE:    INTEGRAL Offline
TRIGGER_NUM:    8663,   Sub_Num: 3
GRB_RA:         248.5372d {+16h 34m 09s} (J2000),
                248.9360d {+16h 35m 45s} (current),
                247.5686d {+16h 30m 16s} (1950)
GRB_DEC:        -51.8390d {-51d 50' 20"} (J2000),
                -51.8805d {-51d 52' 49"} (current),
                -51.7350d {-51d 44' 05"} (1950)
GRB_ERROR:      1.50 [arcmin, radius, statistical only]
GRB_INTEN:      16.62 [sigma]
GRB_TIME:       85953.88 SOD {23:52:33.88} UT
GRB_DATE:       19045 TJD;   197 DOY;   20/07/15
SC_RA:          234.98 [deg] (J2000)
SC_DEC:         -56.61 [deg] (J2000)
SUN_POSTN:      115.87d {+07h 43m 28s}  +21.31d {+21d 18' 29"}
SUN_DIST:       132.73 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      56.24d {+03h 44m 58s}  +16.99d {+16d 59' 33"}
MOON_DIST:      143.69 [deg]
GAL_COORDS:     333.66, -2.78 [deg] galactic lon,lat of the burst
ECL_COORDS:     254.94,-29.52 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.  
COMMENTS:       Time_Scale=50.0000 and Time_Error=50.0000.  
COMMENTS:       refined_coordinates_after_offline_analysis

GCN Circular #28110
S.Mereghetti (INAF, IASF-Milano), D.Gotz (CEA, Saclay), E.Bozzo, C.Ferrigno, V.Savchenko (ISDC, Versoix), L.Ducci (IAAT, Germany and ISDC, Versoix) and J.Borkowski (CAMK, Torun) report:
a gamma ray burst lasting about 160 s has been detected by IBAS in the IBIS/ISGRI data at 23:51:40 UT of July 15, 2020.
The refined coordinates (J2000) are:
```
R.A.= 248.5372   deg
DEC.=  -51.8392  deg
```
with an uncertainty of 1.5 arcmin (90% c.l.).
Due to telemetry saturation, we can provide only lower limits to its peak flux and fluence. The peak flux is greater than 1.2 ph/cm2/s (20-200 keV, 1-s integration time) and the fluence in the same energy range is greater than 1.8e-6 erg/cm2.
A plot of the light curve will be posted at http://ibas.iasf-milano.inaf.it/IBAS_Results.html
GCN Circular #28111
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the INTEGRAL GRB 200715A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021018
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 INTEGRAL 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 #28115
A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the INTEGRAL-detected burst GRB 200715A (Mereghetti et al. GCN Circ. 28110), collecting 3.3 ks of Photon Counting (PC) mode data between T0+7.5 ks and T0+26.2 ks.
An uncatalogued X-ray source is detected consistent with being within 266 arcsec of the INTEGRAL position and is above the RASS limit, and is therefore likely the GRB afterglow. The position of this source is RA, Dec=248.5377, -51.8356 which is equivalent to:
```
RA (J2000): 16:34:9.04
Dec(J2000): -51:50:08.0
```
with an uncertainty of 3.7 arcsec (radius, 90% confidence). This position is 13 arcsec from the INTEGRAL position (Mereghetti et al. GCN Circ. 28110).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.06 (+0.32, -0.27).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.1 (+/-0.5). The best-fitting absorption column is 1.06 (+0.60, -0.29) x 10^22 cm^-2, consistent with the Galactic value of 7.6 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.8 x 10^-11 (9.4 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.06 (+0.60, -0.29) x 10^22 cm^-2
Galactic foreground: 7.6 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:	     2.1 (+/-0.5)
```
If the light curve continues to decay with a power-law decay index of 1.06, the count rate at T+24 hours will be 6.2 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.0 x 10^-13 (5.8 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00021018. The results of the full analysis of the XRT observations are available at https://www.swift.ac.uk/ToO_GRBs/00021018.
This circular is an official product of the Swift-XRT team.

Back to JG's homepage

Jochen Greiner, last update: 16-Jul-2020 [Disclaimer]