batgrbproduct analysis for trigger=1442454
batgrbproduct Analysis for Trigger=1442454
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 Jan 21 12:57:57 EST 2026
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1442454/batgroup_hand_proc
======================================================================
Trigger: 01442454 Segment: 000
BAT Trigger Time: 790624863.232 [s; MET]
Trigger Stop: 790624865.28 [s; MET]
UTC: 2026-01-20T18:00:26.154800 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 284.66555499343 Dec: 61.9118595655486 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.73
Image Trigger?: NO
Rate S/N Ratio: 32.6190128606002 [ if not an image trigger ]
Image S/N Ratio: 7.73
Flight Position: [ source = BAT ]
RA: 284.66555499343 Dec: 61.9118595655486 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 284.701279682395 Dec: 61.9053298695425 [deg; J2000]
{ 18h 58m 48.3s , +61d 54' 19.2" }
+/- 2.00218418922539 [arcmin] (estimated 90% radius based on SNR)
+/- 0.787796549704047 [arcmin] (formal 1-sigma fit error)
SNR: 11.2823181091512
Angular difference between Flight and Ground position is 1.082692 arcmin
Partial Coding Fraction: 0.09472656 [ including projection effects ]
Duration
T90: 4.4799998998642 +/- 0.944948669266659
Measured from: -0.20799994468689
to: 4.27199995517731 [s; relative to TRIGTIME]
T50: 2.11199986934662 +/- 0.45254824555045
Measured from: 0.815999984741211
to: 2.92799985408783 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.47599995136261
to: 1.47599995136261 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.335999965667725
to: 4.59200000762939 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.091812 0.435982 0.682379 0.241348
0.064225 0.064724 0.062026 0.046361 [error]
Peak -0.002647 0.104384 0.261780 0.068659
0.030027 0.030645 0.033592 0.023389 [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 8.38e-08 2.16e-07 4.48e-07 2.36e-06 1.21e-06 3.11e-06 erg/cm2
Error 2.40e-08 3.87e-08 5.38e-08 6.07e-07 1.45e-07 6.15e-07 erg/cm2
Peak flux Power-law 8.30e-01 9.97e-01 8.66e-01 1.29e+00 3.14e+00 3.98e+00 ph/cm2/s
Error 3.62e-01 3.02e-01 1.98e-01 4.65e-01 8.38e-01 9.19e-01 ph/cm2/s
Fluence Cutoff-PL 4.22e-08 2.12e-07 5.53e-07 6.63e-07 1.18e-06 1.47e-06 erg/cm2
Error 2.65e-08 4.68e-08 8.18e-08 4.62e-07 1.50e-07 4.64e-07 erg/cm2
Peak flux Cutoff-PL 8.48e-02 7.33e-01 1.66e+00 4.93e-01 2.91e+00 2.97e+00 ph/cm2/s
Error 1.76e-01 5.95e-01 3.80e-01 2.38e-01 7.01e-01 7.37e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band 1.29e-01 8.22e-01 1.60e+00 5.17e-01 3.00e+00 3.06e+00 ph/cm2/s
Error 1.22e-01 3.31e-01 3.24e-01 -------- -------- -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.950 0.206 - - 2.22e-02 3.11e-03 57.220 57
CPL -0.928 1.345 103.9 38.6 1.10e-01 1.58e-01 48.410 56
The chi2 of BB fit is 48.84 which shows a significant improvement in the fit over a PL.
Check the BB fit.
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.206 0.297 - - 2.68e-02 6.66e-03 78.090 57
CPL -4.072 3.735 84.6 10.7 1.45e+00 1.11e+01 58.100 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: 3.520000 sec.
T50 in the 50-300 keV band: 1.984000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 4.928 -0.336 4.592
T90 4.480 -0.208 4.272
T50 2.112 0.816 2.928
Peak 1.000 0.476 1.476
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
284.7013 +61.9053 0.0170 55.8 -177.9 1.5577 11.3 TRIG_01442454
------------------------------------------
Foreground time interval of the image:
-0.336 4.592 (delta_t = 4.928 [sec])
Background time interval of the image:
-239.232 -173.710 (delta_t = 65.522 [sec])
-172.232 -167.302 (delta_t = 4.930 [sec])
-115.232 -0.336 (delta_t = 114.896 [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 -0.336 sec. to 4.592 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.949757 ( -0.211817 0.199582 )
Norm@50keV : 2.22419E-02 ( -0.00313547 0.00307596 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.22 using 59 PHA bins.
# Reduced chi-squared = 1.004 for 57 degrees of freedom
# Null hypothesis probability = 4.668663e-01
Photon flux (15-150 keV) in 4.928 sec: 2.55505 ( -0.360672 0.368288 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.20707e-06 ( -1.44771e-07 1.4478e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.336 sec. to 4.592 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.928301 ( -1.53412 1.1562 )
Epeak [keV] : 103.888 ( -18.9252 58.3409 )
Norm@50keV : 0.110045 ( -0.0675477 0.248686 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.41 using 59 PHA bins.
# Reduced chi-squared = 0.8645 for 56 degrees of freedom
# Null hypothesis probability = 7.544545e-01
Photon flux (15-150 keV) in 4.928 sec: 2.35385 ( -0.35354 0.37123 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.18411e-06 ( -1.50895e-07 1.49432e-07 ) ergs/cm2
Band function
Time interval is from -0.336 sec. to 4.592 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.20107 ( -1.33929 -1.20336 )
beta : -2.17985 ( 2.16936 0.970888 )
Epeak [keV] : 96.3934 ( -38.8002 54.9848 )
Norm@50keV : 0.144009 ( -0.145445 7.89908 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.98 using 59 PHA bins.
# Reduced chi-squared = 0.8725 for 55 degrees of freedom
# Null hypothesis probability = 7.373824e-01
Photon flux (15-150 keV) in 4.928 sec: 2.32456 ( 4.67544 -0.36353 ) 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] : 24.8115 (-3.01551 3.78408)
R^2/D10^2 : 6.78780E-02 (-0.0253749 0.0367213)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.84 using 59 PHA bins.
# Reduced chi-squared = 0.8569 for 57 degrees of freedom
# Null hypothesis probability = 7.705741e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.592e-08 9.780e-09
25- 50 2.030e-07 3.896e-08
50-150 9.275e-07 1.466e-07
15-150 1.166e-06 1.917e-07
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-20.3859 -200)
Norm : 11.7179 (-1.51329 1.51329)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.439e-07 8.208e-08
25- 50 2.768e-07 1.520e-07
50-150 6.071e-07 3.358e-07
15-150 1.028e-06 5.665e-07
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 : 1.42948E-04 (-0.000142947 -0.000142947)
kT2 [keV] : 21.6121 (-4.4079 6.15984)
R2^2/D10^2 : 9.24477E-02 (-0.0457105 0.0325954)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Peak spectrum fit
Power-law model
Time interval is from 0.476 sec. to 1.476 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.20602 ( -0.304724 0.290227 )
Norm@50keV : 2.68004E-02 ( -0.00669704 0.00662053 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 78.09 using 59 PHA bins.
# Reduced chi-squared = 1.370 for 57 degrees of freedom
# Null hypothesis probability = 3.332091e-02
Photon flux (15-150 keV) in 1 sec: 3.14497 ( -0.824456 0.852087 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.71406e-07 ( -6.22858e-08 6.23077e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.476 sec. to 1.476 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -4.07163 ( -4.88155 2.58812 )
Epeak [keV] : 84.6455 ( -9.48127 11.8777 )
Norm@50keV : 1.44957 ( -1.4526 20.7616 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.10 using 59 PHA bins.
# Reduced chi-squared = 1.038 for 56 degrees of freedom
# Null hypothesis probability = 3.977495e-01
Photon flux (15-150 keV) in 1 sec: 2.91080 ( -0.66951 0.7333 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.2217e-07 ( -6.5101e-08 6.52e-08 ) ergs/cm2
Band function
Time interval is from 0.476 sec. to 1.476 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.19947 ( -2.74643 -4.18106 )
beta : -10.0000 ( 10 20 )
Epeak [keV] : 84.4229 ( -9.27857 12.0346 )
Norm@50keV : 1.57681 ( -1.57401 1.73356 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.11 using 59 PHA bins.
# Reduced chi-squared = 1.057 for 55 degrees of freedom
# Null hypothesis probability = 3.615273e-01
Photon flux (15-150 keV) in 1 sec: 3.00083 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.23264e-07 ( 0 0 ) ergs/cm2
Single BB
XSPEC: quit
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 22.9705 (-3.21953 3.82418)
R^2/D10^2 : 0.122085 (-0.0534698 0.0843801)
(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 1.168e-08 4.350e-09
25- 50 6.333e-08 2.107e-08
50-150 2.496e-07 7.320e-08
15-150 3.246e-07 8.375e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-54.572 -200)
Norm : 14.6453 (-3.44167 3.44167)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.647e-08 2.182e-08
25- 50 7.016e-08 4.197e-08
50-150 1.539e-07 9.235e-08
15-150 2.605e-07 1.528e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.27463E-02 (3.28998 -0.0727463)
R1^2/D10^2 : 3.03224E+12 (-3.03225e+12 -3.03225e+12)
kT2 [keV] : 22.9694 (-3.21842 3.82527)
R2^2/D10^2 : 0.122106 (-0.0534889 0.0843611)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Plot creation:
Wed Jan 21 13:33:10 EST 2026