batgrbproduct analysis for trigger=1348587
batgrbproduct Analysis for Trigger=1348587
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done of the amount of data for this trigger downloaded to date.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
- 4) This page will be updated for up to 15 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.48
Process Start Time (local time): Thu Sep 11 21:33:14 EDT 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1348587/batgroup_hand_proc
======================================================================
Trigger: 01348587 Segment: 000
BAT Trigger Time: 779246902.464 [s; MET]
Trigger Stop: 779246906.56 [s; MET]
UTC: 2025-09-11T01:27:46.157620 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 263.762248030132 Dec: -16.8437337609845 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.6
Image Trigger?: NO
Rate S/N Ratio: 13.9283882771841 [ if not an image trigger ]
Image S/N Ratio: 9.6
Flight Position: [ source = BAT ]
RA: 263.762248030132 Dec: -16.8437337609845 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 263.752403089244 Dec: -16.8411170880077 [deg; J2000]
{ 17h 35m 00.6s , -16d 50' 28.0" }
+/- 0.803068694523316 [arcmin] (estimated 90% radius based on SNR)
+/- 0.24606598357112 [arcmin] (formal 1-sigma fit error)
SNR: 41.6088733518817
Angular difference between Flight and Ground position is 0.586753 arcmin
Partial Coding Fraction: 0.2929688 [ including projection effects ]
Duration
T90: 128.419999957085 +/- 87.2344493784463
Measured from: 10.0520000457764
to: 138.472000002861 [s; relative to TRIGTIME]
T50: 21.4239999055862 +/- 0.549763605952981
Measured from: 106.060000061989
to: 127.483999967575 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 103.94000005722
to: 104.94000005722 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.35199999809265
to: 147.243999958038 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 3.995492 7.527118 7.157031 2.163184
0.176266 0.181442 0.159039 0.126857 [error]
Peak 0.173271 0.326973 0.391484 0.179107
0.017706 0.022005 0.022401 0.017930 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
=== Fluence/Peak Flux Summary ===
Model Band1 Band2 Band3 Band4 Band5 Total
15-25 25-50 50-100 100-350 15-150 15-350 keV
Fluence Power-law 1.74e-06 3.49e-06 5.46e-06 1.89e-05 1.52e-05 2.96e-05 erg/cm2
Error 9.86e-08 1.19e-07 1.57e-07 1.23e-06 4.08e-07 1.29e-06 erg/cm2
Peak flux Power-law 2.03e+00 2.64e+00 2.52e+00 4.24e+00 8.61e+00 1.14e+01 ph/cm2/s
Error 2.76e-01 2.20e-01 1.72e-01 6.24e-01 5.86e-01 7.69e-01 ph/cm2/s
Fluence Cutoff-PL 1.57e-06 3.54e-06 5.69e-06 1.28e-05 1.51e-05 2.37e-05 erg/cm2
Error 1.29e-07 1.26e-07 2.00e-07 2.64e-06 4.22e-07 2.63e-06 erg/cm2
Peak flux Cutoff-PL 1.95e+00 2.66e+00 2.57e+00 3.72e+00 8.56e+00 1.09e+01 ph/cm2/s
Error 3.47e-01 2.27e-01 1.70e-01 1.11e+00 5.94e-01 9.65e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band -------- -------- -------- -------- -------- -------- ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.354 0.047 - - 1.05e-02 2.85e-04 66.730 57
CPL 1.003 0.197 170.5 84.5 1.48e-02 2.80e-03 56.830 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.072 0.112 - - 7.44e-02 4.87e-03 44.180 57
CPL 0.926 0.318 450.5 0.0 8.58e-02 2.91e-02 43.810 56
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^-{Ph_index} (minus sign is not included in the index)
Ph_90err : 90% error of the photon index
Epeak : Epeak in keV
Epeak_90err: 90% error of Epeak
Norm : normalization at 50 keV in PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedom
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
T90 in the 50-300 keV band: 59.968000 sec.
T50 in the 50-300 keV band: 21.184000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 148.596 -1.352 147.244
T90 128.420 10.052 138.472
T50 21.424 106.060 127.484
Peak 1.000 103.940 104.940
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
263.7524 -16.8411 0.0046 50.0 -4.7 22.8591 41.6 TRIG_01348587
------------------------------------------
Foreground time interval of the image:
-1.352 147.244 (delta_t = 148.596 [sec])
Background time interval of the image:
-239.464 -1.352 (delta_t = 238.112 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) The mask-weighted light curves are using the flight position.
- 3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 4) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 5) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 6) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) For long bursts, a spectral fit of the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -1.352 sec. to 147.244 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.35362 ( -0.0472579 0.0469911 )
Norm@50keV : 1.04960E-02 ( -0.000285578 0.000285183 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.73 using 59 PHA bins.
# Reduced chi-squared = 1.171 for 57 degrees of freedom
# Null hypothesis probability = 1.773745e-01
Photon flux (15-150 keV) in 148.6 sec: 1.26541 ( -0.0390716 0.0392139 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.52209e-05 ( -4.07718e-07 4.07806e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.352 sec. to 147.244 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00322 ( -0.201442 0.192958 )
Epeak [keV] : 170.495 ( -40.6879 128.239 )
Norm@50keV : 1.47927E-02 ( -0.00248919 0.00311606 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.83 using 59 PHA bins.
# Reduced chi-squared = 1.015 for 56 degrees of freedom
# Null hypothesis probability = 4.439036e-01
Photon flux (15-150 keV) in 148.6 sec: 1.23697 ( -0.04154 0.04174 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.50547e-05 ( -4.225e-07 4.20984e-07 ) ergs/cm2
Band function
Time interval is from -1.352 sec. to 147.244 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.44595E-02 ( -0.697915 0.448288 )
beta : -1.45698 ( 1.4662 0.0874614 )
Epeak [keV] : 58.6442 ( -41.4684 166.416 )
Norm@50keV : 5.47217E-02 ( -0.041642 141.587 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.46 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 55 degrees of freedom
# Null hypothesis probability = 4.572725e-01
Photon flux (15-150 keV) in 148.6 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 19.9191 ( )
R^2/D10^2 : 5.59114E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 304.81 using 59 PHA bins.
# Reduced chi-squared = 5.3475 for 57 degrees of freedom
# Null hypothesis probability = 1.483063e-35
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.365e-07 3.388e-08
25- 50 3.162e-06 1.412e-07
50-150 9.295e-06 3.812e-07
15-150 1.309e-05 3.767e-07
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 5.45889 ( )
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.020e-06 6.241e-08
25- 50 3.886e-06 1.278e-07
50-150 8.522e-06 2.526e-07
15-150 1.443e-05 4.399e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.53599 (-0.88793 0.9781)
R1^2/D10^2 : 0.581516 (-0.167129 0.253047)
kT2 [keV] : 31.3261 (-2.79049 3.77897)
R2^2/D10^2 : 9.72746E-03 (-0.00320991 0.00391828)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.406e-06 1.616e-07
25- 50 3.679e-06 2.274e-07
50-150 9.981e-06 7.073e-07
15-150 1.507e-05 8.842e-07
Peak spectrum fit
Power-law model
Time interval is from 103.940 sec. to 104.940 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.07155 ( -0.112632 0.111132 )
Norm@50keV : 7.44127E-02 ( -0.00487818 0.00486268 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.18 using 59 PHA bins.
# Reduced chi-squared = 0.7750 for 57 degrees of freedom
# Null hypothesis probability = 8.927749e-01
Photon flux (15-150 keV) in 1 sec: 8.60916 ( -0.585389 0.586664 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.85211e-07 ( -5.32302e-08 5.33141e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 103.940 sec. to 104.940 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.926189 ( -0.436752 0.198836 )
Epeak [keV] : 450.545 ( -450.545 -450.545 )
Norm@50keV : 8.57778E-02 ( -0.0148697 0.0433445 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.81 using 59 PHA bins.
# Reduced chi-squared = 0.7822 for 56 degrees of freedom
# Null hypothesis probability = 8.818428e-01
Photon flux (15-150 keV) in 1 sec: 8.56171 ( -0.59232 0.59654 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.83659e-07 ( -5.3913e-08 5.3797e-08 ) ergs/cm2
Band function
Time interval is from 103.940 sec. to 104.940 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.99999 ( -4.99999 -4.99999 )
beta : -1.08716 ( -0.116392 0.116484 )
Epeak [keV] : 23.6827 ( -23.6827 8.11063 )
Norm@50keV : 7296.69 ( -466.31 1.48175e+07 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.90 using 59 PHA bins.
# Reduced chi-squared = 0.7981 for 55 degrees of freedom
# Null hypothesis probability = 8.587607e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
XSPEC: quit
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 23.6248 (-2.04811 2.30387)
R^2/D10^2 : 0.243416 (-0.0619052 0.0814093)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.430e-08 3.290e-09
25- 50 1.338e-07 1.530e-08
50-150 5.571e-07 4.910e-08
15-150 7.152e-07 5.545e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-9.31298 -200)
Norm : 36.0938 (-2.408 2.408)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.990e-08 6.420e-09
25- 50 1.729e-07 1.490e-08
50-150 3.793e-07 1.045e-07
15-150 6.421e-07 1.129e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.31559 (-1.49672 1.84035)
R1^2/D10^2 : 5.74395 (-3.03663 7.39521)
kT2 [keV] : 33.8359 (-4.76684 7.35263)
R2^2/D10^2 : 6.97048E-02 (-0.0318693 0.0440583)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.314e-08 2.279e-08
25- 50 1.515e-07 4.092e-08
50-150 5.855e-07 1.162e-07
15-150 8.001e-07 1.429e-07
Plot creation:
Fri Sep 12 06:03:11 EDT 2025