batgrbproduct Analysis for Trigger=370791
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 page will be updated for up to 8 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.45
Process Start Time (local time): Sun Sep 27 07:50:41 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger370791/GCN5_download_cron
======================================================================
Trigger: 00370791 Segment: 000
BAT Trigger Time: 275694953.536 [s; MET]
Trigger Stop: 275694954.56 [s; MET]
UTC: 2009-09-26T21:55:48.416220 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 46.3178528437853 Dec: -39.0113731127945 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.74
Image Trigger?: NO
Rate S/N Ratio: 14.6969384566991 [ if not an image trigger ]
Image S/N Ratio: 6.74
Flight Position: [ source = BAT ]
RA: 46.3178528437853 Dec: -39.0113731127945 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 46.3116028983215 Dec: -38.9968804443128 [deg; J2000]
{ 03h 05m 14.8s , -38d 59' 48.8" }
+/- 0.852036826812221 [arcmin] (estimated 90% radius based on SNR)
+/- 0.265110419660294 [arcmin] (formal 1-sigma fit error)
SNR: 38.2352180282555
Angular difference between Flight and Ground position is 0.917090 arcmin
Partial Coding Fraction: 0.265625 [ including projection effects ]
Duration
T90: 111.55999994278 +/- 11.3978841829371
Measured from: -15.5039998888969
to: 96.0560000538826 [s; relative to TRIGTIME]
T50: 29.567999958992 +/- 2.59943762203215
Measured from: -3.17999988794327
to: 26.3880000710487 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -1.30800002813339
to: -0.308000028133392 [s; relative to TRIGTIME]
Total Fluence
Measured from: -21.6119999885559
to: 135.727999985218 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.489345 4.485399 3.520141 0.625680
0.088964 0.096999 0.086513 0.070046 [error]
Peak 0.066652 0.145411 0.125472 0.044337
0.011116 0.013350 0.012202 0.009191 [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 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Power-law 8.25e-01 9.94e-01 8.67e-01 1.30e+00 3.14e+00 3.98e+00 ph/cm2/s
Error 1.60e-01 1.20e-01 9.56e-02 2.98e-01 3.28e-01 4.09e-01 ph/cm2/s
Fluence Cutoff-PL 8.55e-07 2.07e-06 2.89e-06 2.59e-06 7.27e-06 8.40e-06 erg/cm2
Error 6.85e-08 7.03e-08 1.06e-07 5.34e-07 2.41e-07 5.69e-07 erg/cm2
Peak flux Cutoff-PL 7.52e-01 1.02e+00 9.10e-01 9.05e-01 3.10e+00 3.59e+00 ph/cm2/s
Error 1.98e-01 1.31e-01 1.20e-01 4.50e-01 3.35e-01 5.97e-01 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 3.61e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.537 0.000 - - 5.18e-03 0.00e+00 125.480 57
CPL 0.517 0.236 78.2 7.0 1.55e-02 3.90e-03 58.340 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.197 0.168 - - 2.68e-02 2.67e-03 45.970 57
CPL 0.819 0.594 177.2 0.0 3.98e-02 2.89e-02 44.960 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: 109.632000 sec.
T50 in the 50-300 keV band: 23.680000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 157.340 -21.612 135.728
T90 111.560 -15.504 96.056
T50 29.568 -3.180 26.388
Peak 1.000 -1.308 -0.308
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
46.3116 -38.9969 0.0050 40.1 144.3 6.4029 38.2 TRIG_00370791
------------------------------------------
Foreground time interval of the image:
-21.612 9.265 (delta_t = 30.877 [sec])
Background time interval of the image:
-239.536 -21.612 (delta_t = 217.924 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) 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.
- 4) 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.
- 5) 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 -21.612 sec. to 135.728 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.53744 ( )
Norm@50keV : 5.17725E-03 ( )
------------------------------------------------------------
# Chi-Squared = 125.48 using 59 PHA bins.
# Reduced chi-squared = 2.2014 for 57 degrees of freedom
# Null hypothesis probability = 4.655373e-07
Photon flux (15-150 keV) in 157.3 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.612 sec. to 135.728 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.517163 ( -0.242261 0.230258 )
Epeak [keV] : 78.2280 ( -5.83023 8.1545 )
Norm@50keV : 1.55071E-02 ( -0.00332092 0.00447941 )
------------------------------------------------------------
# Chi-Squared = 58.34 using 59 PHA bins.
# Reduced chi-squared = 1.042 for 56 degrees of freedom
# Null hypothesis probability = 3.892229e-01
Photon flux (15-150 keV) in 157.3 sec: 0.614714 ( -0.020907 0.020984 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.26643e-06 ( -2.40559e-07 2.40512e-07 ) ergs/cm2
Band function
Time interval is from -21.612 sec. to 135.728 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.457521 ( -0.274373 0.323936 )
beta : -2.52772 ( 2.52714 0.42689 )
Epeak [keV] : 75.7717 ( -8.45074 9.94004 )
Norm@50keV : 1.67051E-02 ( -0.00432754 0.00761596 )
------------------------------------------------------------
# Chi-Squared = 57.99 using 59 PHA bins.
# Reduced chi-squared = 1.054 for 55 degrees of freedom
# Null hypothesis probability = 3.655975e-01
Photon flux (15-150 keV) in 157.3 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -1.308 sec. to -0.308 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.19744 ( -0.168938 0.166203 )
Norm@50keV : 2.67640E-02 ( -0.00267395 0.00266961 )
------------------------------------------------------------
# Chi-Squared = 45.97 using 59 PHA bins.
# Reduced chi-squared = 0.8065 for 57 degrees of freedom
# Null hypothesis probability = 8.519315e-01
Photon flux (15-150 keV) in 1 sec: 3.14041 ( -0.32754 0.328377 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.7173e-07 ( -2.8898e-08 2.89863e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.308 sec. to -0.308 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.819100 ( -0.728203 0.459724 )
Epeak [keV] : 177.212 ( -177.212 -177.212 )
Norm@50keV : 3.98230E-02 ( -0.0150144 0.042752 )
------------------------------------------------------------
# Chi-Squared = 44.96 using 59 PHA bins.
# Reduced chi-squared = 0.8028 for 56 degrees of freedom
# Null hypothesis probability = 8.547110e-01
Photon flux (15-150 keV) in 1 sec: 3.09991 ( -0.33454 0.3352 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.68427e-07 ( -2.998e-08 2.9782e-08 ) ergs/cm2
Band function
Time interval is from -1.308 sec. to -0.308 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.818090 ( -0.263124 0.646478 )
beta : -9.37125 ( 9.78981 19.7898 )
Epeak [keV] : 176.025 ( -57.8278 333.671 )
Norm@50keV : 4.00026E-02 ( -0.0101976 0.0128916 )
------------------------------------------------------------
# Chi-Squared = 44.96 using 59 PHA bins.
# Reduced chi-squared = 0.8175 for 55 degrees of freedom
# Null hypothesis probability = 8.309716e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Sun Sep 27 08:15:20 EDT 2009