batgrbproduct analysis for trigger=1423875
batgrbproduct Analysis for Trigger=1423875
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): Mon Dec 15 10:38:19 EST 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1423875/GCN5_download_cron
======================================================================
Trigger: 01423875 Segment: 000
BAT Trigger Time: 787395774.4 [s; MET]
Trigger Stop: 787395774.656 [s; MET]
UTC: 2025-12-14T09:02:17.541040 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 330.216936794547 Dec: -9.16703482485966 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.62
Image Trigger?: NO
Rate S/N Ratio: 22.0227155455452 [ if not an image trigger ]
Image S/N Ratio: 8.62
Flight Position: [ source = BAT ]
RA: 330.216936794547 Dec: -9.16703482485966 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 330.222355717108 Dec: -9.15479978873412 [deg; J2000]
{ 22h 00m 53.4s , -09d 09' 17.3" }
+/- 1.1612174626899 [arcmin] (estimated 90% radius based on SNR)
+/- 0.352999709546966 [arcmin] (formal 1-sigma fit error)
SNR: 24.5688441461941
Angular difference between Flight and Ground position is 0.801211 arcmin
Partial Coding Fraction: 0.9921875 [ including projection effects ]
Duration
T90: 9.37999987602234 +/- 0.728889582383917
Measured from: 0.00400018692016602
to: 9.3840000629425 [s; relative to TRIGTIME]
T50: 4.65600001811981 +/- 0.537062514259083
Measured from: 0.704000115394592
to: 5.3600001335144 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.131999969482422
to: 0.868000030517578 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.192000031471252
to: 9.97200000286102 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.318985 0.371981 0.214938 0.039870
0.020268 0.021367 0.017756 0.013545 [error]
Peak 0.067983 0.103846 0.081966 0.016174
0.006863 0.007952 0.006777 0.004623 [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 9.13e-08 1.40e-07 1.62e-07 3.58e-07 4.99e-07 7.51e-07 erg/cm2
Error 9.60e-09 9.48e-09 1.69e-08 7.64e-08 3.92e-08 9.22e-08 erg/cm2
Peak flux Power-law 6.13e-01 6.66e-01 5.15e-01 6.54e-01 2.04e+00 2.45e+00 ph/cm2/s
Error 8.65e-02 5.97e-02 5.24e-02 1.33e-01 1.71e-01 2.11e-01 ph/cm2/s
Fluence Cutoff-PL 8.73e-08 1.46e-07 1.63e-07 1.95e-07 4.83e-07 5.92e-07 erg/cm2
Error 1.09e-08 1.22e-08 1.79e-08 1.30e-07 4.43e-08 1.08e-07 erg/cm2
Peak flux Cutoff-PL 5.44e-01 7.12e-01 5.50e-01 3.30e-01 2.00e+00 2.14e+00 ph/cm2/s
Error 1.03e-01 7.32e-02 6.20e-02 1.97e-01 1.75e-01 2.58e-01 ph/cm2/s
Fluence Band 8.60e-08 1.47e-07 1.59e-07 2.78e-07 4.85e-07 6.72e-07 erg/cm2
Error 1.11e-08 -------- -------- -------- -------- -------- 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 1.794 0.124 - - 5.34e-03 4.07e-04 41.790 57
CPL 1.425 0.471 71.0 -25.8 8.47e-03 5.45e-03 39.950 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.370 0.135 - - 1.69e-02 1.42e-03 58.370 57
CPL 0.700 0.603 98.9 120.3 3.66e-02 2.80e-02 54.140 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: 5.312000 sec.
T50 in the 50-300 keV band: 1.536000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 10.164 -0.192 9.972
T90 9.380 0.004 9.384
T50 4.656 0.704 5.360
Peak 1.000 -0.132 0.868
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
330.2224 -9.1548 0.0078 7.1 80.6 0.9107 24.6 TRIG_01423875
------------------------------------------
Foreground time interval of the image:
-0.192 9.101 (delta_t = 9.293 [sec])
Background time interval of the image:
-163.999 -74.430 (delta_t = 89.569 [sec])
-73.400 -0.192 (delta_t = 73.208 [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 -0.192 sec. to 9.972 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.79443 ( -0.122382 0.125258 )
Norm@50keV : 5.33611E-03 ( -0.000409295 0.00040449 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.79 using 59 PHA bins.
# Reduced chi-squared = 0.7332 for 57 degrees of freedom
# Null hypothesis probability = 9.346288e-01
Photon flux (15-150 keV) in 10.16 sec: 0.733723 ( -0.0501096 0.0501458 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.99208e-07 ( -3.89959e-08 3.93801e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.192 sec. to 9.972 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.42513 ( -0.51786 0.423372 )
Epeak [keV] : 71.0308 ( -19.3407 -71.0308 )
Norm@50keV : 8.46564E-03 ( -0.00335497 0.00754422 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.95 using 59 PHA bins.
# Reduced chi-squared = 0.7133 for 56 degrees of freedom
# Null hypothesis probability = 9.482001e-01
Photon flux (15-150 keV) in 10.16 sec: 0.721473 ( -0.052343 0.052311 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.82576e-07 ( -4.41472e-08 4.44744e-08 ) ergs/cm2
Band function
Time interval is from -0.192 sec. to 9.972 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.42296 ( 1.42304 0.426373 )
beta : -9.36997 ( 9.3714 19.3714 )
Epeak [keV] : 72.0981 ( -20.6983 55.5348 )
Norm@50keV : 8.43636E-03 ( -0.00332778 0.00281931 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.95 using 59 PHA bins.
# Reduced chi-squared = 0.7264 for 55 degrees of freedom
# Null hypothesis probability = 9.365394e-01
Photon flux (15-150 keV) in 10.16 sec: 0.751535 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.84511e-07 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.6886 (-1.00353 1.11163)
R^2/D10^2 : 0.190941 (-0.0547244 0.0758165)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 89.99 using 59 PHA bins.
# Reduced chi-squared = 1.579 for 57 degrees of freedom
# Null hypothesis probability = 3.483165e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.591e-08 7.168e-09
25- 50 1.705e-07 1.443e-08
50-150 1.376e-07 2.276e-08
15-150 3.640e-07 3.139e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 106.447 (-26.0173 35.2395)
Norm : 3.16364 (-0.281125 0.359776)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.399e-08 9.444e-09
25- 50 1.470e-07 1.189e-08
50-150 2.466e-07 7.625e-08
15-150 4.776e-07 8.788e-08
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.18791 (-1.22095 1.36186)
R1^2/D10^2 : 1.36210 (-0.669959 0.94775)
kT2 [keV] : 21.8518 (-4.18236 7.09633)
R2^2/D10^2 : 1.41325E-02 (-0.00925708 0.0188005)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.623e-08 2.209e-08
25- 50 1.454e-07 3.634e-08
50-150 2.472e-07 1.201e-07
15-150 4.788e-07 1.356e-07
Peak spectrum fit
Power-law model
Time interval is from -0.132 sec. to 0.868 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.36989 ( -0.135082 0.135731 )
Norm@50keV : 1.68595E-02 ( -0.00141823 0.00141511 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.37 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 57 degrees of freedom
# Null hypothesis probability = 4.247342e-01
Photon flux (15-150 keV) in 1 sec: 2.03959 ( -0.171369 0.17147 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.63943e-07 ( -1.52829e-08 1.53782e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.132 sec. to 0.868 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.699896 ( -0.644021 0.561519 )
Epeak [keV] : 98.9396 ( -26.6714 213.963 )
Norm@50keV : 3.65958E-02 ( -0.0171686 0.0388523 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.14 using 59 PHA bins.
# Reduced chi-squared = 0.9668 for 56 degrees of freedom
# Null hypothesis probability = 5.455983e-01
Photon flux (15-150 keV) in 1 sec: 1.99967 ( -0.17535 0.17503 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57654e-07 ( -1.6428e-08 1.644e-08 ) ergs/cm2
Band function
Time interval is from -0.132 sec. to 0.868 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.656035 ( -0.593896 0.655496 )
beta : -2.10145 ( 2.12432 0.73067 )
Epeak [keV] : 94.5301 ( -62.9247 187.092 )
Norm@50keV : 3.87624E-02 ( -0.0186816 1.12729 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.03 using 59 PHA bins.
# Reduced chi-squared = 0.9823 for 55 degrees of freedom
# Null hypothesis probability = 5.117389e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.61689e-07 ( 0 0 ) ergs/cm2
Single BB
XSPEC: quit
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 16.1161 (-1.54924 1.7487)
R^2/D10^2 : 0.192421 (-0.0577603 0.0802146)
(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 1.032e-08 1.599e-09
25- 50 4.368e-08 5.165e-09
50-150 7.952e-08 1.204e-08
15-150 1.335e-07 1.385e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-31.4369 -200)
Norm : 8.43654 (-0.700186 0.700186)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.100e-08 2.225e-09
25- 50 4.041e-08 6.490e-09
50-150 8.862e-08 3.621e-08
15-150 1.500e-07 4.224e-08
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.25520 (-2.67046 3.60016)
R1^2/D10^2 : 1.47555 (-0.972884 5.54948)
kT2 [keV] : 24.1463 (-5.16046 16.1824)
R2^2/D10^2 : 3.81385E-02 (-0.0323597 0.0592085)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.686e-08 7.663e-09
25- 50 4.088e-08 1.381e-08
50-150 9.871e-08 4.781e-08
15-150 1.565e-07 6.042e-08
Plot creation:
Mon Dec 15 10:41:58 EST 2025