batgrbproduct Analysis for Trigger=345551
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 v2.42
Process Start Time (local time): Sat Mar 7 11:10:37 EST 2009
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger345551/GCN5_download_cron
======================================================================
Trigger: 00345551 Segment: 000
BAT Trigger Time: 258090402.432 [s; MET]
Trigger Stop: 258090414.592 [s; MET]
UTC: 2009-03-07T03:46:37.877980 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 244.979295086239 Dec: -28.6441582093691 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 5.73
Image Trigger?: NO
Rate S/N Ratio: 10.3923048454133 [ if not an image trigger ]
Image S/N Ratio: 5.73
Flight Position: [ source = BAT ]
RA: 244.979295086239 Dec: -28.6441582093691 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 245.007218608076 Dec: -28.6467358017333 [deg; J2000]
{ 16h 20m 01.7s , -28d 38' 48.2" }
+/- 3.31227989127135 [arcmin] (estimated 90% radius based on SNR)
+/- 1.92809529064664 [arcmin] (formal 1-sigma fit error)
SNR: 5.49641819399822
Angular difference between Flight and Ground position is 1.478457 arcmin
Partial Coding Fraction: 0.875 [ including projection effects ]
Duration
T90: 22 +/- 6.40312423743285
Measured from: -7.43199992179871
to: 14.5680000782013 [s; relative to TRIGTIME]
T50: 11 +/- 7.81024967590665
Measured from: -1.43199992179871
to: 9.56800007820129 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 5.56799998879433
to: 6.56799998879433 [s; relative to TRIGTIME]
Total Fluence
Measured from: -7.43200001120567
to: 16.5679999887943 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.062958 0.142950 0.099303 0.045622
0.030195 0.027641 0.024192 0.021972 [error]
Peak 0.012102 0.014384 0.003880 0.000228
0.006208 0.005779 0.004886 0.004559 [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 2.11e-08 5.00e-08 9.45e-08 4.34e-07 2.56e-07 6.00e-07 erg/cm2
Error 9.46e-09 1.35e-08 2.27e-08 2.48e-07 5.92e-08 2.58e-07 erg/cm2
Peak flux Power-law 9.24e-02 8.20e-02 5.00e-02 4.63e-02 2.44e-01 2.71e-01 ph/cm2/s
Error 7.60e-02 6.41e-02 3.77e-02 8.33e-02 1.37e-01 1.53e-01 ph/cm2/s
Fluence Cutoff-PL 1.52e-08 5.56e-08 1.02e-07 8.27e-08 2.26e-07 2.55e-07 erg/cm2
Error 1.15e-08 1.84e-08 3.00e-08 3.24e-07 7.79e-08 3.34e-07 erg/cm2
Peak flux Cutoff-PL 9.52e-02 1.15e-01 1.70e-02 8.71e-05 2.27e-01 2.27e-01 ph/cm2/s
Error 6.68e-02 6.25e-02 4.25e-02 6.54e-02 1.21e-01 1.21e-01 ph/cm2/s
Fluence Band 1.01e-08 6.23e-08 9.69e-08 1.97e-07 2.29e-07 4.05e-07 erg/cm2
Error 1.38e-08 1.66e-08 6.56e-08 5.36e-08 1.82e-07 0.00e+00 erg/cm2
Peak flux Band 8.56e-02 1.02e-01 4.41e-02 2.25e-02 2.44e-01 2.26e-01 ph/cm2/s
Error 7.45e-02 5.72e-02 4.28e-02 3.65e-02 1.37e-01 1.25e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.080 0.393 - - 1.01e-03 2.24e-04 69.630 57
CPL -0.452 2.184 84.0 4973.3 5.38e-03 3.26e-02 68.525 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.712 1.082 - - 1.83e-03 1.47e-03 59.465 57
CPL -2.397 0.000 33.7 476.9 1.15e+00 8.85e+00 58.530 0
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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 24.000 -7.432 16.568
T90 22.000 -7.432 14.568
T50 11.000 -1.432 9.568
Peak 1.000 5.568 6.568
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
245.0072 -28.6467 0.0348 22.4 164.1 0.3446 5.5 TRIG_00345551
------------------------------------------
Foreground time interval of the image:
-7.432 16.568 (delta_t = 24.000 [sec])
Background time interval of the image:
-60.432 -20.282 (delta_t = 40.150 [sec])
-19.432 -7.432 (delta_t = 12.000 [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 -7.432 sec. to 16.568 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.08003 ( -0.406887 0.378431 )
Norm@50keV : 1.014327E-03 ( -2.250153E-04 2.228861E-04) )
------------------------------------------------------------
Chi-Squared = 69.63002 using 59 PHA bins.
Reduced chi-squared = 1.221579 for 57 degrees of freedom
Null hypothesis probability = 0.122
Photon flux (15-150 keV) in 24.00 sec: 0.117445 ( -0.0267786 0.02709 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.56169e-07 ( -5.88319e-08 5.96592e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.432 sec. to 16.568 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.452027 ( -2.54797 1.81979 )
Epeak [keV] : 84.0169 ( -30.6925 9915.98 )
Norm@50keV : 5.378262E-03 ( -5.378262E-03 5.986905E-02) )
------------------------------------------------------------
Chi-Squared = 68.52467 using 59 PHA bins.
but latest trial 6.524731E-02 gives Chi-Squared = 2.74516
Reduced chi-squared = 1.223655 for 56 degrees of freedom
Null hypothesis probability = 0.122
Photon flux (15-150 keV) in 24.00 sec: 0.108576 ( -0.0443655 0.030837 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.25703e-07 ( -7.82278e-08 7.75133e-08 ) ergs/cm2
Band function
Time interval is from -7.432 sec. to 16.568 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 2.10575 ( -2.59102 0.303233 )
beta : -1.79557 ( -1.80167 0.862776 )
Epeak [keV] : 60.1900 ( -14.3412 9.59044 )
Norm@50keV : 4.099233E-02 ( -0.562734 3.13740 )
------------------------------------------------------------
Chi-Squared = 66.30274 using 59 PHA bins.
Reduced chi-squared = 1.205504 for 55 degrees of freedom
Null hypothesis probability = 0.141
Photon flux (15-150 keV) in 24.00 sec: 0.104303 ( -0.0250969 0.022514 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.28654e-07 ( -4.9615e-08 5.76012e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 5.568 sec. to 6.568 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.71192 ( -1.06176 1.10136 )
Norm@50keV : 1.831248E-03 ( -1.831248E-03 1.102065E-03) )
------------------------------------------------------------
Chi-Squared = 59.46487 using 59 PHA bins.
Reduced chi-squared = 1.043243 for 57 degrees of freedom
Null hypothesis probability = 0.386
Photon flux (15-150 keV) in 1.000 sec: 0.244072 ( -0.136067 0.137297 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.69287e-08 ( -1.02261e-08 1.13126e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.568 sec. to 6.568 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.39668 ( )
Epeak [keV] : 33.7095 ( -10.2202 943.490 )
Norm@50keV : 1.14762 ( -2.98276 14.7260 )
------------------------------------------------------------
Chi-Squared = 58.52990 using 59 PHA bins.
but latest trial 1256.77 gives Chi-Squared = 6.44253
Reduced chi-squared = 1.045177 for 56 degrees of freedom
Null hypothesis probability = 0.383
Photon flux (15-150 keV) in 1.000 sec: 0.226889 ( -0.120746 0.121469 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.10375e-08 ( -5.96736e-09 1.45203e-08 ) ergs/cm2
Band function
Time interval is from 5.568 sec. to 6.568 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.972695 ( -13.9912 1.00884 )
beta : -9.07523 ( -6.53883 2.41897 )
Epeak [keV] : 52.5907 ( -33.8778 551.078 )
Norm@50keV : 5.367626E-03 ( -24.7223 17.7493 )
------------------------------------------------------------
Chi-Squared = 59.28690 using 59 PHA bins.
Reduced chi-squared = 1.077944 for 55 degrees of freedom
Null hypothesis probability = 0.322
Photon flux (15-150 keV) in 1.000 sec: 0.243905 ( -0.129373 0.143629 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.32504e-08 ( -7.15596e-09 1.19311e-08 ) ergs/cm2
Plot creation:
Sat Mar 7 11:27:54 EST 2009