batgrbproduct Analysis for Trigger=276212
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 v2.41
Process Start Time (local time): Thu Dec 13 18:13:10 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger276212/SDC
======================================================================
Trigger: 00276212 Segment: 000
BAT Trigger Time: 198672247.872 [s; MET]
Trigger Stop: 198672248.896 [s; MET]
UTC: 2007-04-19T10:44:05.971820 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 315.718504424161 Dec: -31.2666947301328 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.02
Image Trigger?: NO
Rate S/N Ratio: 17.4355957741627 [ if not an image trigger ]
Image S/N Ratio: 7.02
Flight Position: [ source = BAT ]
RA: 315.718504424161 Dec: -31.2666947301328 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 315.705336455252 Dec: -31.2660465017078 [deg; J2000]
{ 21h 02m 49.3s , -31d 15' 57.8" }
+/- 0.753491237779711 [arcmin] (estimated 90% radius based on SNR)
+/- 0.255415218448534 [arcmin] (formal 1-sigma fit error)
SNR: 45.5743981739218
RA = 21h 2m 49.3s (315.705336 deg.)
Dec = -31d 15' 58" (-31.266047 deg.)
Angular difference between Flight and Ground position is 0.676449 arcmin
Partial Coding Fraction: 0.6640625 [ including projection effects ]
Duration
T90: 236.395999997854 +/- 15.6903577877183
Measured from: -3.88800001144409
to: 232.50799998641 [s; relative to TRIGTIME]
T50: 66.7759999930859 +/- 4.20158875014816
Measured from: 18.9560000002384
to: 85.7319999933243 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.280000001192093
to: 0.719999998807907 [s; relative to TRIGTIME]
Total Fluence
Measured from: -11.6960000097752
to: 313.719999998808 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.008578 4.710070 3.135364 0.713626
0.085648 0.086800 0.076133 0.064281 [error]
Peak 0.046072 0.061240 0.048657 0.022735
0.006403 0.006562 0.006059 0.005032 [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 1.26e-06 2.05e-06 2.52e-06 6.11e-06 7.55e-06 1.19e-05 erg/cm2
Error 6.99e-08 6.27e-08 8.26e-08 4.80e-07 1.98e-07 5.11e-07 erg/cm2
Peak flux Power-law 4.02e-01 4.48e-01 3.57e-01 4.72e-01 1.38e+00 1.68e+00 ph/cm2/s
Error 9.34e-02 6.04e-02 5.07e-02 1.50e-01 1.65e-01 2.00e-01 ph/cm2/s
Fluence Cutoff-PL 1.23e-06 2.05e-06 2.53e-06 5.64e-06 7.52e-06 1.12e-05 erg/cm2
Error 9.18e-08 6.50e-08 9.22e-08 1.12e-06 2.14e-07 1.02e-06 erg/cm2
Peak flux Cutoff-PL 4.01e-01 4.48e-01 3.57e-01 4.69e-01 1.38e+00 1.68e+00 ph/cm2/s
Error 9.34e-02 6.04e-02 5.08e-02 1.49e-01 1.65e-01 2.00e-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 3.77e-01 4.39e-01 3.62e-01 8.44e-01 1.71e+00 0.00e+00 ph/cm2/s
Error 3.96e-02 5.60e-02 4.35e-02 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 1.701 0.054 - - 2.51e-03 6.44e-05 29.398 57
CPL 1.601 0.169 223.7 0.0 2.77e-03 0.00e+00 29.198 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.327 0.224 - - 1.15e-02 1.33e-03 63.757 57
CPL 1.324 0.225 9986.4 5000.0 1.16e-02 1.33e-03 63.781 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: 103.488000 sec.
T50 in the 50-300 keV band: 55.808000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 325.416 -11.696 313.720
T90 236.396 -3.888 232.508
T50 66.776 18.956 85.732
Peak 1.000 -0.280 0.720
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
315.7053 -31.2660 0.0042 30.3 20.1 3.3951 45.6 TRIG_00276212
------------------------------------------
Foreground time interval of the image:
-11.696 19.733 (delta_t = 31.429 [sec])
Background time interval of the image:
-239.872 -11.696 (delta_t = 228.176 [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.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -11.696 sec. to 313.720 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.70057 ( -5.361032E-02 5.376363E-02) )
Norm@50keV : 2.507475E-03 ( -6.441167E-05 6.440468E-05) )
------------------------------------------------------------
Chi-Squared = 29.39776 using 59 PHA bins.
Reduced chi-squared = 0.5157502 for 57 degrees of freedom
Null hypothesis probability = 0.999
Photon flux (15-150 keV) in 325.4 sec: 0.333087 ( -0.010314 0.010387 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.55413e-06 ( -1.97973e-07 1.98299e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -11.696 sec. to 313.720 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.60088 ( -0.187689 0.150161 )
Epeak [keV] : 223.749 ( )
Norm@50keV : 2.772764E-03 ( )
------------------------------------------------------------
Chi-Squared = 29.19842 using 59 PHA bins.
Reduced chi-squared = 0.5214003 for 56 degrees of freedom
Null hypothesis probability = 0.999
Photon flux (15-150 keV) in 325.4 sec: 0.330837 ( -0.01221 0.011928 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.52351e-06 ( -2.28333e-07 1.99633e-07 ) ergs/cm2
Band function
Time interval is from -11.696 sec. to 313.720 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.39520 ( -8.56480 1.28000 )
beta : -1.70034 ( -5.430520E-02 5.347311E-02) )
Epeak [keV] : 36.2860 ( -233.964 9652.05 )
Norm@50keV : 4.627037E-03 ( -2.097355E-04 69.8707 )
------------------------------------------------------------
Chi-Squared = 29.41763 using 59 PHA bins.
Reduced chi-squared = 0.5348660 for 55 degrees of freedom
Null hypothesis probability = 0.998
Photon flux (15-150 keV) in 325.4 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 -0.280 sec. to 0.720 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32714 ( -0.224739 0.222958 )
Norm@50keV : 1.152100E-02 ( -1.328573E-03 1.324888E-03) )
------------------------------------------------------------
Chi-Squared = 63.75690 using 59 PHA bins.
Reduced chi-squared = 1.118542 for 57 degrees of freedom
Null hypothesis probability = 0.251
Photon flux (15-150 keV) in 1.000 sec: 1.38159 ( -0.16481 0.16554 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.13116e-07 ( -1.46443e-08 1.4761e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.280 sec. to 0.720 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32391 ( -0.226635 0.224320 )
Epeak [keV] : 9986.39 ( -9986.38 13.6055 )
Norm@50keV : 1.156714E-02 ( -1.333610E-03 1.331660E-03) )
------------------------------------------------------------
Chi-Squared = 63.78108 using 59 PHA bins.
Reduced chi-squared = 1.138948 for 56 degrees of freedom
Null hypothesis probability = 0.222
Photon flux (15-150 keV) in 1.000 sec: 1.38106 ( -0.16475 0.16549 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.13121e-07 ( -1.46457e-08 1.4794e-08 ) ergs/cm2
Band function
Time interval is from -0.280 sec. to 0.720 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.08360 ( -8.91640 2.40439 )
beta : -1.32712 ( -8.67288 0.224704 )
Epeak [keV] : 35.3277 ( -35.2277 1944.47 )
Norm@50keV : 2.208713E-02 ( -1.188518E-02 421.926 )
------------------------------------------------------------
Chi-Squared = 63.75691 using 59 PHA bins.
Reduced chi-squared = 1.159217 for 55 degrees of freedom
Null hypothesis probability = 0.196
Photon flux (15-150 keV) in 1.000 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Thu Dec 13 18:33:26 EST 2007