| Summary table |
|---|
| Variable |
Value |
Source |
| GRB_name_Fermi |
GRB100225115 |
|
| T0 |
2:45:30.891 UTC |
Fermi_GBM |
| ra |
310.3000° |
Fermi_LAT |
| decl |
-59.4000° |
Fermi_LAT |
| pos_error |
9.00e-01° |
Fermi_LAT |
| T90 |
12.992 s |
Fermi_GBM |
| T90_error |
1.925 s |
Fermi_GBM |
| T90_start |
2:45:30.891 UTC |
Fermi_GBM |
| fluence |
5.85e-06 erg/cm² |
Fermi_GBM |
| fluence_error |
8.18e-08 erg/cm² |
Fermi_GBM |
| T100 |
12.992 s |
|
| GBM_located |
False |
|
| mjd |
55252.11494086806 |
Fermi_GBM |
| Fermi GBM table |
|---|
| GRB_name_Fermi |
GRB100225115 |
| trigger_name |
bn100225115 |
| ra |
310.3000° |
| decl |
-59.4000° |
| pos_error |
3.42e+00° |
| datum |
2010-02-25 |
| t_trigger |
2:45:31.147 UTC |
| T90 |
12.992 s |
| T90_error |
1.925 s |
| T90_start |
2:45:30.891 UTC |
| fluence |
5.85e-06 erg/cm² |
| fluence_error |
8.18e-08 erg/cm² |
| flux_1024 |
3.82e+00 erg/cm²/s |
| flux_1024_error |
1.47e-01 erg/cm²/s |
| flux_1024_time |
6.46e+00 erg/cm²/s |
| flux_64 |
5.30e+00 erg/cm²/s |
| flux_64_error |
6.18e-01 erg/cm²/s |
| IPN table |
|---|
| GRB_name |
GRB100225A |
| ra |
310.3000° |
| decl |
-59.4000° |
| pos_error |
1.20e+00° |
| Fermi LAT table |
|---|
| GRB_name_Fermi |
GRB100225115 |
| GRB_name |
GRB100225A |
| MET |
288758733.0 |
| datum |
2010-02-25 |
| t_trigger |
2:45:31 UTC |
| ra |
310.3000° |
| decl |
-59.4000° |
| pos_error |
9.00e-01° |
| GCN 10449 table |
|---|
| GRB_name |
GRB100225A |
| GCN_number |
10449 |
| Detection_method |
Fermi GBM Det |
| t_trigger |
2:45:31.150 UTC |
| ra |
312.5000° |
| decl |
-54.9000° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 10449
SUBJECT: GRB 100225A: Fermi GBM detection
DATE: 10/02/25 15:41:30 GMT
FROM: Sheila McBreen at MPE
S. Foley (MPE) and S. McBreen (UCD/MPE) report on
behalf of the Fermi GBM Team:
"At 02:45:31.15 UT on 25 February 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100225A (trigger 288758733 / 100225115).
The on-ground calculated location, using the GBM trigger
data, is RA = 312.5, DEC = -54.9 (J2000 degrees,
equivalent to 20 h 50 m, -54 d 54 '), with an uncertainty
of 2.4 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 58 degrees.
The GBM light curve consists of two main pulses
with a duration (T90) of about 13 (+/-3) s (50-300 keV)
starting at -0.256 s. The time-averaged spectrum
from T0-3.8 s to T0+13.6 s is well fit by
a power law function with an exponential high energy cutoff.
The power law index is -0.80 (+0.09/-0.08) and
the cutoff energy, parameterized as Epeak, is
527.30 (+105.00/-76.10) keV (CSTAT 438 for 361 d.o.f.).
The event fluence (8-1000 keV) in this time interval is
(7.6 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+6.4 s in the 8-1000 keV band
is 4.13 +/- 0.20 ph/s/cm^2.
A Band function fits the spectrum equally well (CSTAT 436 for 360 d.o.f.)
with Epeak= 428.00 (+130.00/-86.00) keV, alpha = -0.72 (+0.13/-0.12)
and beta = -2.15 (+0.21/-0.75).
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
|
| GCN 10450 table |
|---|
| GRB_name |
GRB100225A |
| GCN_number |
10450 |
| Detection_method |
Fermi LAT Det |
| t_trigger |
2:45:53 UTC |
| ra |
310.3000° |
| decl |
-59.4000° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 10450
SUBJECT: GRB 100225A: Fermi LAT detection
DATE: 10/02/25 17:24:50 GMT
FROM: Julie McEnery at NASA/GSFC
Fred Piron (LPTA), Masanori Ohno (ISAS/JAXA), Francesco
de Palma (INFN Bari), Elena Moretti (INFN Trieste) and Julie
McEnery (GSFC) report on behalf of the Fermi LAT team
At 02:45:53 (UT) on 25 Feb 2010, the Fermi Large Area
Telescope (LAT) detected gamma rays from the GRB 100225A,
which was triggered and located by the Fermi Gamma-ray Burst
Monitor (GBM) (trigger 288758733 / 100225.115, GCNC 10449).
The angle of the GBM position position with respect to the LAT
boresight was ~60 degrees at the time of the LAT detection,
which is just within the LAT field of view.
The data from the Fermi LAT shows a weak increase in the event
rate that is spatially and temporally correlated with the GBM
emission. It is a relatively weak detection (~4 sigma)
with fewer than 10 excess events.
The best LAT on-ground localization is found to be (RA, Dec =
310.3, -59.4) (J2000) with a 90% containment radius of 1.30 deg
(statistical; 68% containment radius: 0.9 deg) which is consistent
with the GBM localization.
Further analysis is ongoing.
The point of contact for this burst is Fred Piron
(Frederic.PIRON@lpta.in2p3.fr)
The Fermi LAT is a pair conversion telescope designed to cover the
energy band from 20 MeV to greater than 300 GeV.
It is the product of an international collaboration between NASA and
DOE in the U.S. and many scientific institutions across France, Italy,
Japan and Sweden.
|