batgrbproduct analysis for trigger=1327910
batgrbproduct Analysis for Trigger=1327910
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): Fri Jun 27 16:19:22 EDT 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1327910/batgroup_hand_proc
======================================================================
Trigger: 01327910 Segment: 000
BAT Trigger Time: 772560332.352 [s; MET]
Trigger Stop: 772560334.4 [s; MET]
UTC: 2025-06-25T16:04:56.501080 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 261.518500071886 Dec: 22.2652037501118 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.92
Image Trigger?: NO
Rate S/N Ratio: 24 [ if not an image trigger ]
Image S/N Ratio: 7.92
Flight Position: [ source = BAT ]
RA: 261.518500071886 Dec: 22.2652037501118 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 261.516994687898 Dec: 22.2446441826176 [deg; J2000]
{ 17h 26m 04.1s , +22d 14' 40.7" }
+/- 1.91238439557267 [arcmin] (estimated 90% radius based on SNR)
+/- 0.967647013642355 [arcmin] (formal 1-sigma fit error)
SNR: 12.0467003174001
Angular difference between Flight and Ground position is 1.236403 arcmin
Partial Coding Fraction: 0.6875 [ including projection effects ]
Duration
T90: 4 +/- 1.4142135623731
Measured from: -0.351999998092651
to: 3.64800000190735 [s; relative to TRIGTIME]
T50: 2 +/- 1
Measured from: 0.648000001907349
to: 2.64800000190735 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.64800000190735
to: 2.64800000190735 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.351999998092651
to: 3.64800000190735 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.051576 0.133825 0.143120 0.050591
0.015502 0.016108 0.014945 0.012605 [error]
Peak 0.008546 0.042403 0.039604 0.018934
0.007858 0.008066 0.007613 0.006300 [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 2.07e-08 5.15e-08 1.03e-07 5.12e-07 2.78e-07 6.87e-07 erg/cm2
Error 5.36e-09 8.01e-09 1.38e-08 1.59e-07 3.65e-08 1.66e-07 erg/cm2
Peak flux Power-law 1.84e-01 2.46e-01 2.42e-01 4.26e-01 8.11e-01 1.10e+00 ph/cm2/s
Error 8.28e-02 6.97e-02 5.79e-02 2.13e-01 1.91e-01 2.64e-01 ph/cm2/s
Fluence Cutoff-PL 1.82e-08 5.32e-08 1.09e-07 2.78e-07 2.72e-07 4.58e-07 erg/cm2
Error 6.73e-09 8.91e-09 1.73e-08 2.26e-07 3.88e-08 2.29e-07 erg/cm2
Peak flux Cutoff-PL 1.22e-01 2.70e-01 2.83e-01 1.18e-01 7.62e-01 7.93e-01 ph/cm2/s
Error 9.60e-02 8.41e-02 7.64e-02 2.48e-01 1.99e-01 2.93e-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 1.005 0.218 - - 6.43e-03 8.12e-04 48.750 57
CPL 0.504 0.849 173.7 0.0 1.07e-02 1.18e-02 47.830 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.026 0.375 - - 7.04e-03 1.62e-03 51.570 57
CPL -0.680 2.506 86.4 -29.9 4.25e-02 5.31e-01 49.230 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: 2.560000 sec.
T50 in the 50-300 keV band: 1.344000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 4.000 -0.352 3.648
T90 4.000 -0.352 3.648
T50 2.000 0.648 2.648
Peak 1.000 1.648 2.648
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
261.5170 +22.2446 0.0159 28.6 25.9 0.3595 12.0 TRIG_01327910
------------------------------------------
Foreground time interval of the image:
-0.352 3.648 (delta_t = 4.000 [sec])
Background time interval of the image:
-239.352 -0.352 (delta_t = 239.000 [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 -0.352 sec. to 3.648 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00453 ( -0.222069 0.21327 )
Norm@50keV : 6.42778E-03 ( -0.000815065 0.000809663 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.75 using 59 PHA bins.
# Reduced chi-squared = 0.8552 for 57 degrees of freedom
# Null hypothesis probability = 7.735750e-01
Photon flux (15-150 keV) in 4 sec: 0.740326 ( -0.0957092 0.0958897 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.77625e-07 ( -3.64774e-08 3.65838e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.352 sec. to 3.648 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.503974 ( -1.06491 0.633554 )
Epeak [keV] : 173.667 ( -173.665 -173.665 )
Norm@50keV : 1.06672E-02 ( -0.00485044 0.0188276 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.83 using 59 PHA bins.
# Reduced chi-squared = 0.8541 for 56 degrees of freedom
# Null hypothesis probability = 7.732181e-01
Photon flux (15-150 keV) in 4 sec: 0.724995 ( -0.099535 0.099521 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.71622e-07 ( -3.90184e-08 3.85204e-08 ) ergs/cm2
Band function
Time interval is from -0.352 sec. to 3.648 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.500054 ( 0.479756 1.72223 )
beta : -1.44768 ( 1.48568 1.91025 )
Epeak [keV] : 170.065 ( -165.558 423.92 )
Norm@50keV : 1.07642E-02 ( -0.00348868 198023 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.76 using 59 PHA bins.
# Reduced chi-squared = 0.8683 for 55 degrees of freedom
# Null hypothesis probability = 7.450530e-01
Photon flux (15-150 keV) in 4 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] : 22.2242 (-3.3147 4.23387)
R^2/D10^2 : 2.58102E-02 (-0.0109434 0.0175982)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.93 using 59 PHA bins.
# Reduced chi-squared = 0.9636 for 57 degrees of freedom
# Null hypothesis probability = 5.532688e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.393e-09 2.402e-09
25- 50 4.997e-08 1.205e-08
50-150 1.844e-07 4.104e-08
15-150 2.438e-07 4.602e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-27.9798 -200)
Norm : 3.06876 (-0.397029 0.397029)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.057e-08 1.745e-08
25- 50 5.882e-08 3.246e-08
50-150 1.290e-07 7.148e-08
15-150 2.184e-07 1.226e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.71930 (-4.48449 8.35548)
R1^2/D10^2 : 0.228450 (-0.186546 2.36191)
kT2 [keV] : 31.9131 (-8.99642 -31.9131)
R2^2/D10^2 : 7.04196E-03 (-0.00664822 0.0172531)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.761e-08 1.043e-08
25- 50 5.416e-08 2.806e-08
50-150 2.005e-07 1.042e-07
15-150 2.722e-07 1.395e-07
Peak spectrum fit
Power-law model
Time interval is from 1.648 sec. to 2.648 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.02607 ( -0.387396 0.363064 )
Norm@50keV : 7.03709E-03 ( -0.00162143 0.00160966 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.57 using 59 PHA bins.
# Reduced chi-squared = 0.9048 for 57 degrees of freedom
# Null hypothesis probability = 6.780504e-01
Photon flux (15-150 keV) in 1 sec: 0.811458 ( -0.189854 0.191333 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.53989e-08 ( -1.79198e-08 1.81118e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.648 sec. to 2.648 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.680390 ( -3.19433 1.81677 )
Epeak [keV] : 86.4144 ( -26.7007 -86.4144 )
Norm@50keV : 4.24681E-02 ( -0.0424681 1.01986 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.23 using 59 PHA bins.
# Reduced chi-squared = 0.8790 for 56 degrees of freedom
# Null hypothesis probability = 7.271317e-01
Photon flux (15-150 keV) in 1 sec: 0.762171 ( -0.197573 0.199722 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.86625e-08 ( -1.99725e-08 2.02488e-08 ) ergs/cm2
Band function
Time interval is from 1.648 sec. to 2.648 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5 -5 )
beta : -1.39866 ( -2.15752 0.526187 )
Epeak [keV] : 41.2316 ( -41.2308 20.4076 )
Norm@50keV : 30.4218 ( -6.67063 933.893 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.88 using 59 PHA bins.
# Reduced chi-squared = 0.8887 for 55 degrees of freedom
# Null hypothesis probability = 7.062960e-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] : 19.7419 (-4.32737 6.42845)
R^2/D10^2 : 4.26711E-02 (-0.0257678 0.0540448)
(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 3.222e-09 1.361e-09
25- 50 1.591e-08 7.582e-09
50-150 4.589e-08 2.056e-08
15-150 6.502e-08 2.595e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-67.9675 -200)
Norm : 3.36269 (-0.793325 0.793325)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.373e-09 5.145e-09
25- 50 1.611e-08 9.740e-09
50-150 3.533e-08 2.079e-08
15-150 5.980e-08 3.511e-08
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 200.000 (-200 -200)
R1^2/D10^2 : 7.54125E-05 (-7.54379e-05 -7.54379e-05)
kT2 [keV] : 16.2930 (-4.10885 8.10488)
R2^2/D10^2 : 6.79209E-02 (-0.0467013 0.0378248)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.879e-09 2.729e-09
25- 50 1.660e-08 1.395e-08
50-150 5.021e-08 4.198e-08
15-150 7.069e-08 5.765e-08
Plot creation:
Fri Jun 27 16:41:09 EDT 2025