| Summary table |
|---|
| Variable |
Value |
Source |
| GRB_name_Fermi |
GRB090309767 |
|
| T0 |
18:25:06.681 UTC |
Fermi_GBM |
| ra |
174.3000° |
Fermi_GBM |
| decl |
-49.5000° |
Fermi_GBM |
| pos_error |
3.32e+00° |
Fermi_GBM |
| T90 |
56.513 s |
Fermi_GBM |
| T90_error |
5.146 s |
Fermi_GBM |
| T90_start |
18:25:06.681 UTC |
Fermi_GBM |
| fluence |
4.42e-06 erg/cm² |
Fermi_GBM |
| fluence_error |
6.88e-08 erg/cm² |
Fermi_GBM |
| T100 |
56.513 s |
|
| GBM_located |
True |
|
| mjd |
54899.7674384375 |
Fermi_GBM |
| Fermi GBM table |
|---|
| GRB_name_Fermi |
GRB090309767 |
| trigger_name |
bn090309767 |
| ra |
174.3000° |
| decl |
-49.5000° |
| pos_error |
3.32e+00° |
| datum |
2009-03-09 |
| t_trigger |
18:25:07.193 UTC |
| T90 |
56.513 s |
| T90_error |
5.146 s |
| T90_start |
18:25:06.681 UTC |
| fluence |
4.42e-06 erg/cm² |
| fluence_error |
6.88e-08 erg/cm² |
| flux_1024 |
3.46e+00 erg/cm²/s |
| flux_1024_error |
2.05e-01 erg/cm²/s |
| flux_1024_time |
3.80e+01 erg/cm²/s |
| flux_64 |
5.19e+00 erg/cm²/s |
| flux_64_error |
1.81e+00 erg/cm²/s |
| GCN 8971 table |
|---|
| GRB_name |
GRB090309B |
| GCN_number |
8971 |
| Detection_method |
Fermi GBM Det |
| t_trigger |
18:25:07.190 UTC |
| ra |
168.4000° |
| decl |
-55.0000° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8971
SUBJECT: GRB 090309B: Fermi GBM detection
DATE: 09/03/10 16:12:00 GMT
FROM: Alexander van der Horst at NASA/MSFC
A.J. van der Horst (NASA/MSFC/ORAU) reports on behalf of the
Fermi GBM Team:
"At 18:25:07.19 UT on 9 March 2009, the Fermi Gamma-ray Burst Monitor
(GBM) triggered and located GRB 090309B (trigger 258315909 / 090309.767).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 168.4, Dec = -55.0 (J2000 degrees, equivalent to
J2000 11h13m, -55d01'), with a statistical uncertainty of 2.6 degrees
(radius, 1-sigma containment, statistical only; there is additionally
a systematic error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 26 degrees.
The GBM light curve consists of two main peaks, with durations of ~10
and ~25 seconds, and no significant emission above background level in
between for ~25 seconds. The time-averaged spectrum over the two peaks,
from T0-4.1 to T0+5.1 s and from T0+32.8 to T0+54.3 s, is best fit by
a power law with an exponential high-energy cutoff. The index is
-1.52 +/- 0.10 and the cutoff energy, parameterized as Epeak, is
197 +/- 65 keV (chi squared 358 for 360 d.o.f.). The fluence
(8-1000 keV) in this time interval is (4.7 +/- 0.4)E-6 erg/cm^2.
The 1-sec peak photon flux measured starting from T0+37.9s in the
8-1000 keV band is 4.43 +/- 0.17 ph/s/cm^2.
The spectral and temporal analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
|