batgrbproduct Analysis for Trigger=211850
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 13:52:29 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger211850/GCN5_download_cron
======================================================================
Trigger: 00211850 Segment: 000
BAT Trigger Time: 170319184 [s; MET]
Trigger Stop: 170319248 [s; MET]
UTC: 2006-05-26T06:53:02.783720 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 268.506284861314 Dec: -26.4070315915061 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.72
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 5.72
Flight Position: [ source = BAT ]
RA: 268.506284861314 Dec: -26.4070315915061 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 268.530666645391 Dec: -26.4433652205268 [deg; J2000]
{ 17h 54m 07.4s , -26d 26' 36.1" }
+/- 5.58102966372512 [arcmin] (estimated 90% radius based on SNR)
+/- 2.66030430301292 [arcmin] (formal 1-sigma fit error)
SNR: 2.60845663843131
RA = 17h 54m 7.4s (268.530667 deg.)
Dec = -26d 26' 36" (-26.443365 deg.)
Angular difference between Flight and Ground position is 2.543369 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.076023 0.039780 0.019207 0.001683
0.030152 0.026727 0.023010 0.020494 [error]
Peak 0.076023 0.039780 0.019207 0.001683
0.030152 0.026727 0.023010 0.020494 [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 1.39e-08 1.96e-08 2.05e-08 3.94e-08 6.64e-08 9.37e-08 erg/cm2
Error 1.24e-08 1.58e-08 2.19e-08 1.30e-07 5.05e-08 1.43e-07 erg/cm2
Peak flux Power-law 1.42e-02 1.11e-02 5.78e-03 4.37e-03 3.31e-02 3.55e-02 ph/cm2/s
Error 1.30e-02 8.88e-03 6.02e-03 1.22e-02 2.66e-02 2.18e-02 ph/cm2/s
Fluence Cutoff-PL 1.39e-08 1.96e-08 2.05e-08 3.90e-08 6.65e-08 9.41e-08 erg/cm2
Error 1.25e-08 1.58e-08 2.20e-08 1.29e-07 5.05e-08 1.42e-07 erg/cm2
Peak flux Cutoff-PL 1.42e-02 1.11e-02 5.78e-03 4.33e-03 3.31e-02 3.54e-02 ph/cm2/s
Error 1.30e-02 8.89e-03 6.02e-03 1.21e-02 2.66e-02 2.18e-02 ph/cm2/s
Fluence Band 1.35e-08 1.96e-08 2.10e-08 4.16e-08 6.72e-08 8.65e-08 erg/cm2
Error 9.98e-09 1.31e-08 1.78e-08 8.92e-08 4.13e-08 1.41e-07 erg/cm2
Peak flux Band 1.33e-02 1.10e-02 5.71e-03 4.24e-03 3.33e-02 3.58e-02 ph/cm2/s
Error 1.06e-02 7.01e-03 4.62e-03 1.18e-02 2.01e-02 8.52e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.937 1.781 - - 2.27e-04 1.98e-04 38.314 57
CPL 1.041 0.000 50.3 0.0 6.59e-04 6.47e-02 38.638 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.937 1.781 - - 2.27e-04 1.98e-04 38.314 57
CPL 1.041 0.000 50.3 0.0 6.59e-04 9.81e-01 38.638 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 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
268.5307 -26.4434 0.0739 3.2 -143.4 0.1399 2.6 TRIG_00211850
------------------------------------------
Foreground time interval of the image:
0.000 13.740 (delta_t = 13.740 [sec])
15.000 33.102 (delta_t = 18.102 [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
Multiple GTIs in the spectrum
tstart tstop
0.000000 13.740000
15.000000 33.101800
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.93714 ( -1.42720 2.13445 )
Norm@50keV : 2.268062E-04 ( -2.268062E-04 1.685696E-04) )
------------------------------------------------------------
Chi-Squared = 38.31414 using 59 PHA bins.
Reduced chi-squared = 0.6721779 for 57 degrees of freedom
Null hypothesis probability = 0.973
Photon flux (15-150 keV) in 31.84 sec: 3.308548E-02 ( -0.0330855 0.0200811 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.64437e-08 ( -4.67319e-08 5.42735e-08 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
0.000000 13.740000
15.000000 33.101800
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.04101 ( )
Epeak [keV] : 50.3469 ( )
Norm@50keV : 6.591928E-04 ( -2.570190E-04 0.129163 )
------------------------------------------------------------
Chi-Squared = 38.63847 using 59 PHA bins.
but latest trial 0.129420 gives Chi-Squared = 2.07429
Reduced chi-squared = 0.6899728 for 56 degrees of freedom
Null hypothesis probability = 0.963
Photon flux (15-150 keV) in 31.84 sec: 3.307108E-02 ( -0.0330711 0.0200745 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.64682e-08 ( -4.67609e-08 5.42557e-08 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
0.000000 13.740000
15.000000 33.101800
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.47564 ( -8.52436 6.47564 )
beta : -1.92273 ( -8.07727 1.41324 )
Epeak [keV] : 21.8717 ( -21.7717 9978.13 )
Norm@50keV : 5.556042E-04 ( -34.7943 3197.22 )
------------------------------------------------------------
Chi-Squared = 38.31003 using 59 PHA bins.
Reduced chi-squared = 0.6965460 for 55 degrees of freedom
Null hypothesis probability = 0.958
Photon flux (15-150 keV) in 31.84 sec: 3.329553E-02 ( -0.0200689 0.0200915 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.72044e-08 ( -4.06527e-08 4.19495e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 15.000 sec. to 33.102 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.93714 ( -1.42720 2.13445 )
Norm@50keV : 2.268062E-04 ( -2.268062E-04 1.685696E-04) )
------------------------------------------------------------
Chi-Squared = 38.31414 using 59 PHA bins.
Reduced chi-squared = 0.6721779 for 57 degrees of freedom
Null hypothesis probability = 0.973
Photon flux (15-150 keV) in 31.84 sec: 3.308548E-02 ( -0.0330855 0.0200811 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.64437e-08 ( -4.67319e-08 5.42735e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 15.000 sec. to 33.102 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.04101 ( )
Epeak [keV] : 50.3469 ( )
Norm@50keV : 6.591928E-04 ( -2.314552E-04 1.96150 )
------------------------------------------------------------
Chi-Squared = 38.63847 using 59 PHA bins.
but latest trial 1.96173 gives Chi-Squared = 2.49199
Reduced chi-squared = 0.6899728 for 56 degrees of freedom
Null hypothesis probability = 0.963
Photon flux (15-150 keV) in 31.84 sec: 3.307108E-02 ( -0.0330711 0.0200745 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.64682e-08 ( -4.67609e-08 5.42557e-08 ) ergs/cm2
Band function
Time interval is from 15.000 sec. to 33.102 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.47564 ( -8.52436 6.47564 )
beta : -1.92273 ( -8.07727 1.41324 )
Epeak [keV] : 21.8717 ( -21.7717 9978.13 )
Norm@50keV : 5.556042E-04 ( -34.7943 3197.22 )
------------------------------------------------------------
Chi-Squared = 38.31003 using 59 PHA bins.
Reduced chi-squared = 0.6965460 for 55 degrees of freedom
Null hypothesis probability = 0.958
Photon flux (15-150 keV) in 31.84 sec: 3.329553E-02 ( -0.0200689 0.0200915 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.72044e-08 ( -4.06527e-08 4.19495e-08 ) ergs/cm2
Plot creation:
Tue Jan 1 13:58:30 EST 2008