batgrbproduct Analysis for Trigger=331093
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 Oct 9 00:56:38 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger331093/GCN5_download_cron
======================================================================
Trigger: 00331093 Segment: 000
BAT Trigger Time: 245188692.544 [s; MET]
Trigger Stop: 245188694.592 [s; MET]
UTC: 2008-10-08T19:58:09.384500 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 279.987257236876 Dec: -57.4643799585525 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10
Image Trigger?: NO
Rate S/N Ratio: 19.7737199332852 [ if not an image trigger ]
Image S/N Ratio: 10
Flight Position: [ source = BAT ]
RA: 279.987257236876 Dec: -57.4643799585525 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 279.968355834613 Dec: -57.4330008830325 [deg; J2000]
{ 18h 39m 52.4s , -57d 25' 58.8" }
+/- 1.05018215643885 [arcmin] (estimated 90% radius based on SNR)
+/- 0.48115974551494 [arcmin] (formal 1-sigma fit error)
SNR: 28.3622270937696
Angular difference between Flight and Ground position is 1.979159 arcmin
Partial Coding Fraction: 0.8125 [ including projection effects ]
Duration
T90: 185.476000010967 +/- 40.3441495698351
Measured from: -43.2559999227524
to: 142.220000088215 [s; relative to TRIGTIME]
T50: 111.236000031233 +/- 1.89804529987377
Measured from: 1.0840000808239
to: 112.320000112057 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 7.52399998903275
to: 8.52399998903275 [s; relative to TRIGTIME]
Total Fluence
Measured from: -65.2479999959469
to: 201.023999989033 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.170006 2.842551 1.747259 0.392317
0.089130 0.083743 0.072140 0.062756 [error]
Peak 0.044428 0.055681 0.055962 0.008515
0.006352 0.006103 0.005595 0.004361 [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 7.04e-07 1.15e-06 1.42e-06 3.48e-06 4.26e-06 6.76e-06 erg/cm2
Error 4.80e-08 4.57e-08 7.44e-08 3.99e-07 1.74e-07 4.52e-07 erg/cm2
Peak flux Power-law 4.08e-01 4.36e-01 3.32e-01 4.11e-01 1.33e+00 1.59e+00 ph/cm2/s
Error 8.02e-02 5.24e-02 4.55e-02 1.17e-01 1.49e-01 1.79e-01 ph/cm2/s
Fluence Cutoff-PL 6.59e-07 1.18e-06 1.44e-06 2.06e-06 4.13e-06 5.34e-06 erg/cm2
Error 5.90e-08 5.37e-08 7.89e-08 8.65e-07 2.05e-07 8.89e-07 erg/cm2
Peak flux Cutoff-PL 3.65e-01 4.54e-01 3.48e-01 2.42e-01 1.30e+00 1.41e+00 ph/cm2/s
Error 9.82e-02 5.97e-02 5.25e-02 1.89e-01 1.57e-01 2.56e-01 ph/cm2/s
Fluence Band 6.19e-07 1.21e-06 1.40e-06 2.90e-06 4.12e-06 6.10e-06 erg/cm2
Error 6.82e-08 6.27e-08 5.68e-08 8.80e-07 1.86e-07 6.49e-07 erg/cm2
Peak flux Band 3.66e-01 4.54e-01 3.48e-01 2.42e-01 1.30e+00 1.41e+00 ph/cm2/s
Error 9.87e-02 5.97e-02 5.25e-02 1.88e-01 1.56e-01 2.56e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.693 0.072 - - 1.73e-03 6.75e-05 58.733 57
CPL 1.300 0.300 88.2 91.6 2.72e-03 9.11e-04 54.241 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.396 0.193 - - 1.09e-02 1.21e-03 48.270 57
CPL 0.878 0.757 113.4 4964.6 1.95e-02 1.95e-02 46.835 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: 127.808000 sec.
T50 in the 50-300 keV band: 104.320000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 266.272 -65.248 201.024
T90 185.476 -43.256 142.220
T50 111.236 1.084 112.320
Peak 1.000 7.524 8.524
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
279.9684 -57.4330 0.0067 21.4 143.6 3.7127 28.4 TRIG_00331093
------------------------------------------
Foreground time interval of the image:
-65.248 30.757 (delta_t = 96.005 [sec])
Background time interval of the image:
-239.544 -65.248 (delta_t = 174.296 [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
Multiple GTIs in the spectrum
tstart tstop
-65.248000 76.496000
77.456000 201.024000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.69293 ( -7.172680E-02 7.217431E-02) )
Norm@50keV : 1.733711E-03 ( -6.769155E-05 6.738515E-05) )
------------------------------------------------------------
Chi-Squared = 58.73329 using 59 PHA bins.
Reduced chi-squared = 1.030409 for 57 degrees of freedom
Null hypothesis probability = 0.412
Photon flux (15-150 keV) in 265.3 sec: 0.229691 ( -0.009188 0.009214 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.26101e-06 ( -1.73825e-07 1.75151e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-65.248000 76.496000
77.456000 201.024000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30026 ( -0.273911 0.326126 )
Epeak [keV] : 88.1562 ( -18.1445 165.038 )
Norm@50keV : 2.722265E-03 ( -8.342755E-04 9.885516E-04) )
------------------------------------------------------------
Chi-Squared = 54.24069 using 59 PHA bins.
Reduced chi-squared = 0.9685837 for 56 degrees of freedom
Null hypothesis probability = 0.542
Photon flux (15-150 keV) in 265.3 sec: 0.224045 ( -0.01014 0.010159 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.12733e-06 ( -2.04971e-07 2.04573e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-65.248000 76.496000
77.456000 201.024000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.05264 ( -0.530325 2.39365 )
beta : -1.85421 ( -8.14579 0.145251 )
Epeak [keV] : 61.0646 ( -28.6618 81.2045 )
Norm@50keV : 3.952373E-03 ( -1.853701E-03 0.251881 )
------------------------------------------------------------
Chi-Squared = 52.70678 using 59 PHA bins.
Reduced chi-squared = 0.9583051 for 55 degrees of freedom
Null hypothesis probability = 0.563
Photon flux (15-150 keV) in 265.3 sec: 0.224036 ( -0.010151 0.010184 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.12327e-06 ( -1.85392e-07 1.87434e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 7.524 sec. to 8.524 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39609 ( -0.192126 0.193859 )
Norm@50keV : 1.094449E-02 ( -1.215376E-03 1.211207E-03) )
------------------------------------------------------------
Chi-Squared = 48.26953 using 59 PHA bins.
Reduced chi-squared = 0.8468338 for 57 degrees of freedom
Null hypothesis probability = 0.788
Photon flux (15-150 keV) in 1.000 sec: 1.33166 ( -0.14847 0.14876 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.05856e-07 ( -1.307e-08 1.3178e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.524 sec. to 8.524 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.878340 ( -0.865048 0.648343 )
Epeak [keV] : 113.397 ( -42.6409 9886.60 )
Norm@50keV : 1.949513E-02 ( -9.354617E-03 2.970370E-02) )
------------------------------------------------------------
Chi-Squared = 46.83517 using 59 PHA bins.
Reduced chi-squared = 0.8363423 for 56 degrees of freedom
Null hypothesis probability = 0.804
Photon flux (15-150 keV) in 1.000 sec: 1.29812 ( -0.15611 0.1572 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.027e-07 ( -1.45729e-08 6.926e-09 ) ergs/cm2
Band function
Time interval is from 7.524 sec. to 8.524 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.879434 ( -0.647205 0.866265 )
beta : -5.38509 ( -4.61491 4.12044 )
Epeak [keV] : 113.574 ( -113.474 9886.43 )
Norm@50keV : 1.946540E-02 ( -3.681250E-03 2.988670E-02) )
------------------------------------------------------------
Chi-Squared = 46.83521 using 59 PHA bins.
Reduced chi-squared = 0.8515493 for 55 degrees of freedom
Null hypothesis probability = 0.775
Photon flux (15-150 keV) in 1.000 sec: 1.29830 ( -0.15628 0.15587 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02184e-07 ( -1.41102e-08 1.4187e-08 ) ergs/cm2
Plot creation:
Thu Oct 9 01:22:54 EDT 2008