batgrbproduct Analysis for Trigger=215987
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 Jan 1 19:05:04 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger215987/GCN5_download_cron
======================================================================
Trigger: 00215987 Segment: 000
BAT Trigger Time: 172922848 [s; MET]
Trigger Stop: 172923168 [s; MET]
UTC: 2006-06-25T10:07:26.722560 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 255.237329530426 Dec: -46.1887856433436 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.61
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 5.61
Flight Position: [ source = BAT ]
RA: 255.237329530426 Dec: -46.1887856433436 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 255.274038749812 Dec: -46.1019833714849 [deg; J2000]
{ 17h 01m 05.8s , -46d 06' 07.1" }
+/- 6.02428876193418 [arcmin] (estimated 90% radius based on SNR)
+/- 3.84256465043355 [arcmin] (formal 1-sigma fit error)
SNR: 2.33866095349111
RA = 17h 1m 5.8s (255.274039 deg.)
Dec = -46d 6' 7" (-46.101983 deg.)
Angular difference between Flight and Ground position is 5.427094 arcmin
Partial Coding Fraction: 0.9609375 [ including projection effects ]
Duration
T90: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
T50: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 320 second)
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.077226 -0.002900 -0.008431 0.031526
0.035003 0.031293 0.026993 0.024872 [error]
Peak 0.077226 -0.002900 -0.008431 0.031526
0.035003 0.031293 0.026993 0.024872 [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 2.03e-08 3.29e-09 2.49e-10 2.01e-11 2.39e-08 2.39e-08 erg/cm2
Error 1.64e-08 9.50e-09 5.28e-09 5.17e-09 2.70e-08 2.83e-08 erg/cm2
Peak flux Power-law 2.15e-02 2.03e-03 7.70e-05 3.02e-06 2.36e-02 2.36e-02 ph/cm2/s
Error 1.70e-02 5.40e-03 1.48e-03 5.99e-04 2.10e-02 2.10e-02 ph/cm2/s
Fluence Cutoff-PL 2.10e-08 3.25e-09 1.31e-10 2.07e-12 2.40e-08 2.47e-08 erg/cm2
Error 1.37e-08 9.50e-09 5.27e-09 5.11e-09 2.90e-08 3.02e-08 erg/cm2
Peak flux Cutoff-PL 2.15e-02 2.03e-03 7.67e-05 2.99e-06 2.36e-02 2.36e-02 ph/cm2/s
Error 1.70e-02 5.39e-03 1.48e-03 5.94e-04 2.10e-02 2.10e-02 ph/cm2/s
Fluence Band 1.99e-08 3.07e-09 2.19e-10 1.67e-11 2.32e-08 4.61e-08 erg/cm2
Error 1.93e-08 9.32e-09 2.45e-09 1.80e-09 1.83e-08 0.00e+00 erg/cm2
Peak flux Band 2.07e-02 1.59e-03 4.58e-05 1.36e-06 2.24e-02 2.07e-02 ph/cm2/s
Error 2.64e-02 5.27e-03 1.55e-04 2.45e-04 1.69e-02 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 5.833 3.716 - - 6.69e-06 7.38e-05 72.624 57
CPL 1.706 6.364 1.6 47.3 1.32e-02 4.03e+01 72.683 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 5.833 3.716 - - 6.69e-06 7.38e-05 72.624 57
CPL 1.706 4.493 1.6 47.3 1.32e-02 4.03e+01 72.683 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 320.000 0.000 320.000
T90 320.000 0.000 320.000
T50 320.000 0.000 320.000
Peak 320.000 0.000 320.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
255.2740 -46.1020 0.0820 19.2 -32.8 0.1438 2.3 TRIG_00215987
------------------------------------------
Foreground time interval of the image:
0.000 33.078 (delta_t = 33.078 [sec])
Background time interval of the image:
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 0.000 sec. to 33.078 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 5.83260 ( -3.26482 4.16740 )
Norm@50keV : 6.688956E-06 ( -6.688956E-06 1.409149E-04) )
------------------------------------------------------------
Chi-Squared = 72.62356 using 59 PHA bins.
Reduced chi-squared = 1.274098 for 57 degrees of freedom
Null hypothesis probability = 7.945E-02
Photon flux (15-150 keV) in 33.08 sec: 2.363493E-02 ( -0.0192908 0.0226191 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.38516e-08 ( -1.99433e-08 3.40655e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.078 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.70565 ( -4.70565 8.02217 )
Epeak [keV] : 1.64019 ( -1.63019 93.0441 )
Norm@50keV : 1.317479E-02 ( -1.317479E-02 80.6057 )
------------------------------------------------------------
Chi-Squared = 72.68285 using 59 PHA bins.
but latest trial 177.088 gives Chi-Squared = 3.10574
Reduced chi-squared = 1.297908 for 56 degrees of freedom
Null hypothesis probability = 6.628E-02
Photon flux (15-150 keV) in 33.08 sec: 2.360805E-02 ( -0.0192837 0.0226171 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.40367e-08 ( -2.40367e-08 3.38815e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.078 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.52392 ( -0.106876 0.114583 )
beta : -3.51575 ( -4.44255 15.4583 )
Epeak [keV] : 12.4733 ( -12.3733 9987.53 )
Norm@50keV : 6.902634E-04 ( -1.228213E-03 1.884989E-02) )
------------------------------------------------------------
Chi-Squared = 75.35066 using 59 PHA bins.
Reduced chi-squared = 1.370012 for 55 degrees of freedom
Null hypothesis probability = 3.560E-02
Photon flux (15-150 keV) in 33.08 sec: 2.235692E-02 ( -0.015569 0.0181904 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.32284e-08 ( -1.94334e-08 1.71547e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.078 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 5.83260 ( -3.26482 4.16740 )
Norm@50keV : 6.688956E-06 ( -6.688956E-06 1.409149E-04) )
------------------------------------------------------------
Chi-Squared = 72.62356 using 59 PHA bins.
Reduced chi-squared = 1.274098 for 57 degrees of freedom
Null hypothesis probability = 7.945E-02
Photon flux (15-150 keV) in 33.08 sec: 2.363493E-02 ( -0.0192908 0.0226191 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.38516e-08 ( -1.99433e-08 3.40655e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.078 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.70565 ( -4.70565 4.28042 )
Epeak [keV] : 1.64019 ( -1.63019 93.0441 )
Norm@50keV : 1.317479E-02 ( -1.317479E-02 80.6057 )
------------------------------------------------------------
Chi-Squared = 72.68285 using 59 PHA bins.
but latest trial 177.088 gives Chi-Squared = 3.10574
Reduced chi-squared = 1.297908 for 56 degrees of freedom
Null hypothesis probability = 6.628E-02
Photon flux (15-150 keV) in 33.08 sec: 2.360805E-02 ( -0.0192837 0.0226171 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.40367e-08 ( -2.40367e-08 3.38815e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.078 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.52392 ( -0.106876 0.114583 )
beta : -3.51575 ( -4.44255 15.4583 )
Epeak [keV] : 12.4733 ( -12.3733 9987.53 )
Norm@50keV : 6.902634E-04 ( -1.228213E-03 1.884989E-02) )
------------------------------------------------------------
Chi-Squared = 75.35066 using 59 PHA bins.
Reduced chi-squared = 1.370012 for 55 degrees of freedom
Null hypothesis probability = 3.560E-02
Photon flux (15-150 keV) in 33.08 sec: 2.235692E-02 ( -0.015569 0.0181904 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.32284e-08 ( -1.94334e-08 1.71547e-08 ) ergs/cm2
Plot creation:
Tue Jan 1 19:09:59 EST 2008