| Summary table |
|---|
| Variable |
Value |
Source |
| GRB_name_Fermi |
GRB151021791 |
|
| T0 |
18:59:28.920 UTC |
GCN_circulars,Fermi GBM Det |
| ra |
104.3400° |
Fermi_GBM |
| decl |
-10.9600° |
Fermi_GBM |
| pos_error |
2.57e+00° |
Fermi_GBM |
| T90 |
7.229 s |
Fermi_GBM |
| T90_error |
0.602 s |
Fermi_GBM |
| T90_start |
18:59:28.926 UTC |
Fermi_GBM |
| fluence |
1.23e-05 erg/cm² |
Fermi_GBM |
| fluence_error |
3.80e-08 erg/cm² |
Fermi_GBM |
| T100 |
7.235 s |
|
| GBM_located |
True |
|
| mjd |
57316.79130694445 |
GCN_circulars,Fermi GBM Det |
| Fermi GBM table |
|---|
| GRB_name_Fermi |
GRB151021791 |
| trigger_name |
bn151021791 |
| ra |
104.3400° |
| decl |
-10.9600° |
| pos_error |
2.57e+00° |
| datum |
2015-10-21 |
| t_trigger |
18:59:28.923 UTC |
| T90 |
7.229 s |
| T90_error |
0.602 s |
| T90_start |
18:59:28.926 UTC |
| fluence |
1.23e-05 erg/cm² |
| fluence_error |
3.80e-08 erg/cm² |
| flux_1024 |
2.15e+01 erg/cm²/s |
| flux_1024_error |
3.86e-01 erg/cm²/s |
| flux_1024_time |
7.68e-01 erg/cm²/s |
| flux_64 |
2.48e+01 erg/cm²/s |
| flux_64_error |
1.63e+00 erg/cm²/s |
| GCN 18434 table |
|---|
| GRB_name |
GRB151021B |
| GCN_number |
18434 |
| Detection_method |
Fermi GBM Det |
| t_trigger |
18:59:28.920 UTC |
| ra |
104.3400° |
| decl |
-10.9600° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 18434
SUBJECT: GRB 151021B: Fermi GBM detection
DATE: 15/10/22 04:10:01 GMT
FROM: Peter Veres at UAH
P. Veres (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 18:59:28.92 UT on 21 October 2015, the Fermi Gamma-Ray Burst
Monitor triggered and located GRB 151021B (trigger 467146772 /
151021791).
The on-ground calculated location, using the GBM trigger data, is RA =
104.340, DEC = -10.960 (J2000 degrees, equivalent to 06 h 57 m, -10 d
58 '), with an uncertainty of 1.20 degrees (radius, 1-sigma
containment, statistical only; there is additionally a systematic
error which we have characterized as a core-plus-tail model, with 90%
of GRBs having a 3.7 deg error and a small tail suffering a larger
than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32]
).
The angle from the Fermi LAT boresight at the GBM trigger time is 83 degrees.
This burst was also independently detected by INTEGRAL SPI-ACS.
The GBM light curve consists of a single pulse with fast rise and
exponential decay with a duration (T90) of about 7.2 s (50-300 keV).
The time-averaged spectrum from T0-0.1 s to T0+9.1 s is well fit by a
power law function with an exponential high-energy cutoff. The power
law index is -0.67 +/- 0.03 and the cutoff energy, parameterized as
Epeak, is 270 +/- 10 keV.
A Band function fits the spectrum equally well with Epeak = 241 +/- 13
keV, alpha = -0.61 +/- 0.04 and beta = -2.6 +/- 0.2.
The event fluence (10-1000 keV) in this time interval is (1.226 +/-
0.004)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from
T0+0.77 s in the 10-1000 keV band is 21.5 +/- 0.4 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final
results will be published in the GBM GRB Catalog."
|