batgrbproduct Analysis for Trigger=332851
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): Tue Oct 28 11:21:34 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger332851/GCN5_download_cron
======================================================================
Trigger: 00332851 Segment: 000
BAT Trigger Time: 246846304 [s; MET]
Trigger Stop: 246846432 [s; MET]
UTC: 2008-10-28T00:25:00.790760 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 121.890264700736 Dec: 2.31110706505449 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 17.95
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 17.95
Flight Position: [ source = BAT ]
RA: 121.890264700736 Dec: 2.31110706505449 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 121.893083962888 Dec: 2.3048737328124 [deg; J2000]
{ 08h 07m 34.3s , +02d 18' 17.5" }
+/- 1.18137660879881 [arcmin] (estimated 90% radius based on SNR)
+/- 0.596195126066878 [arcmin] (formal 1-sigma fit error)
SNR: 23.972119075406
Angular difference between Flight and Ground position is 0.410418 arcmin
Partial Coding Fraction: 0.859375 [ including projection effects ]
Duration
T90: 282.555999994278 +/- 32.5884964277169
Measured from: 50.6360000967979
to: 333.192000091076 [s; relative to TRIGTIME]
T50: 129.139999985695 +/- 8.06813311490682
Measured from: 89.608000099659
to: 218.748000085354 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 211.743999987841
to: 212.743999987841 [s; relative to TRIGTIME]
Total Fluence
Measured from: 29.3440000116825
to: 441.488000005484 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.360028 2.703327 1.589688 0.171847
0.096988 0.097433 0.087681 0.079120 [error]
Peak 0.023716 0.021646 0.013631 0.007070
0.004897 0.004813 0.004410 0.003849 [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 7.43e-07 1.11e-06 1.23e-06 2.59e-06 3.87e-06 5.66e-06 erg/cm2
Error 5.59e-08 5.06e-08 8.73e-08 3.86e-07 1.99e-07 4.61e-07 erg/cm2
Peak flux Power-law 1.85e-01 1.70e-01 1.08e-01 1.05e-01 5.06e-01 5.67e-01 ph/cm2/s
Error 6.60e-02 3.87e-02 3.67e-02 7.29e-02 1.14e-01 1.33e-01 ph/cm2/s
Fluence Cutoff-PL 6.89e-07 1.16e-06 1.23e-06 1.19e-06 3.67e-06 4.27e-06 erg/cm2
Error 6.66e-08 6.26e-08 9.44e-08 6.26e-07 2.35e-07 6.74e-07 erg/cm2
Peak flux Cutoff-PL 1.85e-01 1.70e-01 1.08e-01 1.04e-01 5.06e-01 5.66e-01 ph/cm2/s
Error 6.60e-02 3.87e-02 3.67e-02 7.24e-02 1.14e-01 1.33e-01 ph/cm2/s
Fluence Band 6.82e-07 1.16e-06 1.23e-06 1.18e-06 3.67e-06 4.37e-06 erg/cm2
Error 6.59e-08 6.24e-08 9.42e-08 6.26e-07 2.35e-07 8.86e-07 erg/cm2
Peak flux Band 1.85e-01 1.70e-01 1.08e-01 1.04e-01 5.06e-01 5.66e-01 ph/cm2/s
Error 6.60e-02 3.87e-02 3.67e-02 9.62e-02 1.14e-01 1.33e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.845 0.088 - - 1.02e-03 5.20e-05 64.294 57
CPL 1.247 0.378 58.1 22.4 2.10e-03 9.10e-04 57.955 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.655 0.431 - - 3.87e-03 1.00e-03 39.600 57
CPL 1.653 0.433 9999.0 5000.0 3.88e-03 1.01e-03 39.601 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: 180.864000 sec.
T50 in the 50-300 keV band: 122.688000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 412.144 29.344 441.488
T90 282.556 50.636 333.192
T50 129.140 89.608 218.748
Peak 1.000 211.744 212.744
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
121.8931 +2.3049 0.0080 21.2 25.5 2.8048 24.0 TRIG_00332851
------------------------------------------
Foreground time interval of the image:
29.344 134.801 (delta_t = 105.457 [sec])
Background time interval of the image:
-239.000 -20.270 (delta_t = 218.730 [sec])
-19.000 29.344 (delta_t = 48.344 [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 29.344 sec. to 441.488 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.84538 ( -8.782697E-02 8.915329E-02) )
Norm@50keV : 1.020697E-03 ( -5.216536E-05 5.178188E-05) )
------------------------------------------------------------
Chi-Squared = 64.29439 using 59 PHA bins.
Reduced chi-squared = 1.127972 for 57 degrees of freedom
Null hypothesis probability = 0.236
Photon flux (15-150 keV) in 412.1 sec: 0.143201 ( -0.006702 0.006715 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.86786e-06 ( -1.98587e-07 2.0019e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 29.344 sec. to 441.488 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.24731 ( -0.309733 0.445996 )
Epeak [keV] : 58.0806 ( -8.50292 36.3745 )
Norm@50keV : 2.104592E-03 ( -8.616650E-04 9.593216E-04) )
------------------------------------------------------------
Chi-Squared = 57.95493 using 59 PHA bins.
Reduced chi-squared = 1.034909 for 56 degrees of freedom
Null hypothesis probability = 0.403
Photon flux (15-150 keV) in 412.1 sec: 0.138534 ( -0.007342 0.007361 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.67439e-06 ( -2.34794e-07 2.35944e-07 ) ergs/cm2
Band function
Time interval is from 29.344 sec. to 441.488 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.33291 ( -0.350452 0.383928 )
beta : -7.88071 ( -2.11929 5.94898 )
Epeak [keV] : 59.9900 ( -10.0983 31.9964 )
Norm@50keV : 1.906074E-03 ( -6.489777E-04 1.114849E-03) )
------------------------------------------------------------
Chi-Squared = 57.79494 using 59 PHA bins.
Reduced chi-squared = 1.050817 for 55 degrees of freedom
Null hypothesis probability = 0.372
Photon flux (15-150 keV) in 412.1 sec: 0.138539 ( -0.007354 0.007356 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.66968e-06 ( -2.339e-07 2.36339e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 211.744 sec. to 212.744 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.65451 ( -0.416572 0.444545 )
Norm@50keV : 3.869245E-03 ( -1.025318E-03 9.774303E-04) )
------------------------------------------------------------
Chi-Squared = 39.59998 using 59 PHA bins.
Reduced chi-squared = 0.6947364 for 57 degrees of freedom
Null hypothesis probability = 0.962
Photon flux (15-150 keV) in 1.000 sec: 0.505981 ( -0.114355 0.114393 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.59665e-08 ( -9.7931e-09 1.02264e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 211.744 sec. to 212.744 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.65302 ( -0.418951 0.446483 )
Epeak [keV] : 9999.04 ( -9999.03 0.961914 )
Norm@50keV : 3.878566E-03 ( -1.033721E-03 9.822743E-04) )
------------------------------------------------------------
Chi-Squared = 39.60055 using 59 PHA bins.
Reduced chi-squared = 0.7071527 for 56 degrees of freedom
Null hypothesis probability = 0.952
Photon flux (15-150 keV) in 1.000 sec: 0.505813 ( -0.114319 0.114357 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.59682e-08 ( -9.8004e-09 1.0225e-08 ) ergs/cm2
Band function
Time interval is from 211.744 sec. to 212.744 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.62942 ( -8.37058 1.56018 )
beta : -9.30839 ( -0.691613 8.07090 )
Epeak [keV] : 682.379 ( -682.279 9317.62 )
Norm@50keV : 3.993923E-03 ( -1.151841E-03 2.574755E-02) )
------------------------------------------------------------
Chi-Squared = 39.60955 using 59 PHA bins.
Reduced chi-squared = 0.7201736 for 55 degrees of freedom
Null hypothesis probability = 0.941
Photon flux (15-150 keV) in 1.000 sec: 0.505814 ( -0.114318 0.114303 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.55895e-08 ( -9.1047e-09 1.02246e-08 ) ergs/cm2
Plot creation:
Tue Oct 28 11:55:43 EDT 2008