batgrbproduct analysis for trigger=1515414
batgrbproduct Analysis for Trigger=1515414
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): Wed Oct 7 00:17:14 EDT 2026
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1515414/batgroup_hand_proc
======================================================================
Trigger: 01515414 Segment: 000
BAT Trigger Time: 812929185.216 [s; MET]
Trigger Stop: 812929193.408 [s; MET]
UTC: 2026-10-05T21:39:06.635260 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 255.327361996873 Dec: 1.59024979587568 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.71
Image Trigger?: NO
Rate S/N Ratio: 16 [ if not an image trigger ]
Image S/N Ratio: 10.71
Flight Position: [ source = BAT ]
RA: 255.327361996873 Dec: 1.59024979587568 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 255.322275688703 Dec: 1.58397316074574 [deg; J2000]
{ 17h 01m 17.3s , +01d 35' 02.3" }
+/- 2.21663515620095 [arcmin] (estimated 90% radius based on SNR)
+/- 0.906254904942215 [arcmin] (formal 1-sigma fit error)
SNR: 9.75594849031566
Angular difference between Flight and Ground position is 0.484653 arcmin
Partial Coding Fraction: 0.9375 [ including projection effects ]
Duration
T90: 94 +/- 20.0997512422418
Measured from: 2.78400003910065
to: 96.7840000391006 [s; relative to TRIGTIME]
T50: 63 +/- 44.181444068749
Measured from: 7.78400003910065
to: 70.7840000391006 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.78400003910065
to: 4.78400003910065 [s; relative to TRIGTIME]
Total Fluence
Measured from: 1.78400003910065
to: 106.784000039101 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.301829 0.501530 0.318989 0.103945
0.071232 0.064505 0.053169 0.045081 [error]
Peak 0.019064 0.024106 0.042362 0.009836
0.007158 0.006883 0.006193 0.005039 [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 9.16e-08 1.82e-07 2.81e-07 9.54e-07 7.86e-07 1.51e-06 erg/cm2
Error 2.54e-08 2.98e-08 5.16e-08 4.00e-07 1.27e-07 4.32e-07 erg/cm2
Peak flux Power-law 1.20e-01 1.97e-01 2.44e-01 6.02e-01 7.30e-01 1.16e+00 ph/cm2/s
Error 5.98e-02 6.00e-02 4.42e-02 2.50e-01 1.50e-01 2.43e-01 ph/cm2/s
Fluence Cutoff-PL 9.04e-08 1.83e-07 2.83e-07 8.40e-07 7.82e-07 1.39e-06 erg/cm2
Error 2.84e-08 3.28e-08 5.47e-08 7.00e-07 1.36e-07 5.07e-07 erg/cm2
Peak flux Cutoff-PL 1.07e-01 1.94e-01 2.52e-01 4.92e-01 7.20e-01 1.05e+00 ph/cm2/s
Error 7.75e-02 6.72e-02 5.87e-02 2.84e-01 1.59e-01 3.69e-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 1.372 0.270 - - 7.70e-04 1.13e-04 49.180 57
CPL 1.302 1.399 524.1 0.0 8.33e-04 1.09e-03 49.170 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.686 0.369 - - 6.31e-03 1.40e-03 53.650 57
CPL 0.412 1.437 407.3 0.0 7.86e-03 1.61e-02 53.560 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: 32.256000 sec.
T50 in the 50-300 keV band: 16.960000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 105.000 1.784 106.784
T90 94.000 2.784 96.784
T50 63.000 7.784 70.784
Peak 1.000 3.784 4.784
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
255.3223 +1.5840 0.0197 14.8 143.6 0.8637 9.8 TRIG_01515414
------------------------------------------
Foreground time interval of the image:
1.784 48.685 (delta_t = 46.901 [sec])
Background time interval of the image:
-179.216 1.784 (delta_t = 181.000 [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 1.784 sec. to 106.784 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37179 ( -0.2717 0.268567 )
Norm@50keV : 7.70419E-04 ( -0.000112698 0.000112558 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.18 using 59 PHA bins.
# Reduced chi-squared = 0.8629 for 57 degrees of freedom
# Null hypothesis probability = 7.596941e-01
Photon flux (15-150 keV) in 105 sec: 9.32396E-02 ( -0.0141755 0.0142464 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.86299e-07 ( -1.26185e-07 1.27832e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.784 sec. to 106.784 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30243 ( -1.12296 1.6756 )
Epeak [keV] : 524.134 ( -524.145 -524.145 )
Norm@50keV : 8.32804E-04 ( -0.000169008 0.00200304 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.17 using 59 PHA bins.
# Reduced chi-squared = 0.8780 for 56 degrees of freedom
# Null hypothesis probability = 7.291114e-01
Photon flux (15-150 keV) in 105 sec: 9.28821E-02 ( -0.0149725 0.0145199 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.82422e-07 ( -1.41076e-07 1.30774e-07 ) ergs/cm2
Band function
Time interval is from 1.784 sec. to 106.784 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.665915 ( 0.871339 0.871339 )
beta : -1.46571 ( 1.44543 0.335936 )
Epeak [keV] : 70.9229 ( -70.2676 447.027 )
Norm@50keV : 2.01550E-03 ( -0.00205828 70731.9 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.98 using 59 PHA bins.
# Reduced chi-squared = 0.8906 for 55 degrees of freedom
# Null hypothesis probability = 7.026155e-01
Photon flux (15-150 keV) in 105 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] : 16.5108 (-3.23421 4.33285)
R^2/D10^2 : 7.56006E-03 (-0.00410414 0.00856928)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.58 using 59 PHA bins.
# Reduced chi-squared = 1.063 for 57 degrees of freedom
# Null hypothesis probability = 3.479854e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.441e-08 1.431e-08
25- 50 1.919e-07 4.735e-08
50-150 3.699e-07 1.117e-07
15-150 6.062e-07 1.373e-07
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-69.3573 -200)
Norm : 0.386625 (-0.056638 0.056638)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.011e-07 5.728e-08
25- 50 1.945e-07 1.099e-07
50-150 4.265e-07 2.397e-07
15-150 7.221e-07 4.010e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.50608 (-3.06892 3.74322)
R1^2/D10^2 : 5.14340E-02 (-0.0350386 0.174272)
kT2 [keV] : 36.9750 (-31.5376 -36.975)
R2^2/D10^2 : 4.16856E-04 (-0.000374173 0.00204649)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.184e-08 4.732e-08
25- 50 1.974e-07 1.063e-07
50-150 5.154e-07 2.876e-07
15-150 7.946e-07 4.027e-07
Peak spectrum fit
Power-law model
Time interval is from 3.784 sec. to 4.784 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.686177 ( -0.389472 0.348147 )
Norm@50keV : 6.31103E-03 ( -0.0014397 0.00136482 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.65 using 59 PHA bins.
# Reduced chi-squared = 0.9413 for 57 degrees of freedom
# Null hypothesis probability = 6.014637e-01
Photon flux (15-150 keV) in 1 sec: 0.730326 ( -0.148171 0.150913 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.75183e-08 ( -1.43135e-08 1.43396e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.784 sec. to 4.784 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.412326 ( -2.28152 0.593261 )
Epeak [keV] : 407.267 ( -407.06 -407.06 )
Norm@50keV : 7.85638E-03 ( -0.00244793 0.0298006 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.56 using 59 PHA bins.
# Reduced chi-squared = 0.9565 for 56 degrees of freedom
# Null hypothesis probability = 5.675928e-01
Photon flux (15-150 keV) in 1 sec: 0.719682 ( -0.159984 0.158661 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.734e-08 ( -1.45092e-08 1.44279e-08 ) ergs/cm2
Band function
Time interval is from 3.784 sec. to 4.784 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.836957 ( 0.836957 0.836957 )
beta : -0.686178 ( -0.348155 0.389078 )
Epeak [keV] : 14.9580 ( -14.958 -14.958 )
Norm@50keV : 9.24634E-03 ( -0.00431907 131051 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.65 using 59 PHA bins.
# Reduced chi-squared = 0.9755 for 55 degrees of freedom
# Null hypothesis probability = 5.262529e-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] : 31.7071 (-7.01252 11.9102)
R^2/D10^2 : 9.62935E-03 (-0.00562705 0.0105893)
(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 1.463e-09 5.723e-10
25- 50 9.225e-09 3.785e-09
50-150 6.398e-08 2.468e-08
15-150 7.467e-08 2.893e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-41.3388 -200)
Norm : 3.09951 (-0.633738 0.633738)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.726e-09 4.541e-09
25- 50 1.486e-08 8.620e-09
50-150 3.260e-08 1.869e-08
15-150 5.519e-08 3.244e-08
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.16210 (-4.13438 14.1447)
R1^2/D10^2 : 3.33990 (-3.33066 64022.3)
kT2 [keV] : 34.9628 (-8.65005 36.7698)
R2^2/D10^2 : 7.08565E-03 (-0.00632238 0.00548335)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.898e-09 2.787e-09
25- 50 9.504e-09 4.411e-09
50-150 6.424e-08 3.401e-08
15-150 7.865e-08 3.698e-08
Plot creation:
Wed Oct 7 00:25:46 EDT 2026