batgrbproduct Analysis for Trigger=310125
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): Fri Apr 25 14:14:35 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger310125/GCN5_download_cron
======================================================================
Trigger: 00310125 Segment: 000
BAT Trigger Time: 230793240 [s; MET]
Trigger Stop: 230793328 [s; MET]
UTC: 2008-04-25T05:13:57.257200 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 341.689772081705 Dec: 44.3371798544384 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 19.47
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 19.47
Flight Position: [ source = BAT ]
RA: 341.689772081705 Dec: 44.3371798544384 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 341.69870702022 Dec: 44.3225230569668 [deg; J2000]
{ 22h 46m 47.7s , +44d 19' 21.1" }
+/- 1.42171502966041 [arcmin] (estimated 90% radius based on SNR)
+/- 0.497563661769292 [arcmin] (formal 1-sigma fit error)
SNR: 18.3998689815867
RA = 22h 46m 47.7s (341.698707 deg.)
Dec = 44d 19' 21" (44.322523 deg.)
Angular difference between Flight and Ground position is 0.959385 arcmin
Partial Coding Fraction: 0.6015625 [ including projection effects ]
Duration
T90: 443.548000007868 +/- 250.300212215046
Measured from: -21.4359999895096
to: 422.112000018358 [s; relative to TRIGTIME]
T50: 122.980000019073 +/- 46.7256478062551
Measured from: 14.5119999945164
to: 137.49200001359 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -28.9920000135899
to: -27.9920000135899 [s; relative to TRIGTIME]
Total Fluence
Measured from: -28.9679999947548
to: 672.183999985456 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.408321 1.515462 0.314056 0.052481
0.137237 0.135098 0.118311 0.103365 [error]
Peak 0.055920 0.009615 0.005906 0.005510
0.009851 0.009286 0.007827 0.006738 [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 1.46e-06 6.66e-07 1.84e-07 6.32e-08 2.34e-06 2.37e-06 erg/cm2
Error 1.53e-07 8.50e-08 5.65e-08 3.50e-08 1.98e-07 2.05e-07 erg/cm2
Peak flux Power-law 3.82e-01 1.75e-01 4.83e-02 1.67e-02 6.15e-01 6.22e-01 ph/cm2/s
Error 1.66e-01 1.31e-01 5.16e-02 3.98e-02 2.39e-01 2.45e-01 ph/cm2/s
Fluence Cutoff-PL 1.46e-06 6.66e-07 1.83e-07 6.26e-08 2.34e-06 2.37e-06 erg/cm2
Error 1.53e-07 8.51e-08 5.65e-08 3.47e-08 1.98e-07 2.04e-07 erg/cm2
Peak flux Cutoff-PL 3.82e-01 1.75e-01 4.83e-02 1.65e-02 6.15e-01 6.21e-01 ph/cm2/s
Error 1.66e-01 1.31e-01 5.16e-02 3.95e-02 2.39e-01 2.45e-01 ph/cm2/s
Fluence Band 1.46e-06 6.37e-07 1.42e-07 3.81e-08 2.27e-06 2.27e-06 erg/cm2
Error 1.61e-07 9.49e-08 3.75e-08 2.47e-08 2.29e-07 1.78e-07 erg/cm2
Peak flux Band 3.82e-01 1.75e-01 4.83e-02 1.65e-02 6.15e-01 6.21e-01 ph/cm2/s
Error 1.66e-01 1.31e-01 5.17e-02 3.95e-02 2.39e-01 2.45e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.818 0.289 - - 1.73e-04 3.93e-05 48.178 57
CPL 1.862 0.000 1.7 0.0 5.49e-03 1.79e-03 50.151 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.855 1.088 - - 2.48e-03 2.34e-03 58.004 57
CPL 1.952 1.426 1.3 0.0 1.24e-02 0.00e+00 58.288 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 701.152 -28.968 672.184
T90 443.548 -21.436 422.112
T50 122.980 14.512 137.492
Peak 1.000 -28.992 -27.992
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
341.6987 +44.3225 0.0104 24.8 -107.0 2.6128 18.4 TRIG_00310125
------------------------------------------
Foreground time interval of the image:
-5.799 107.301 (delta_t = 113.100 [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 -28.968 sec. to 672.184 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.81850 ( -0.243396 0.335033 )
Norm@50keV : 1.728448E-04 ( -4.211110E-05 3.648242E-05) )
------------------------------------------------------------
Chi-Squared = 48.17771 using 59 PHA bins.
Reduced chi-squared = 0.8452229 for 57 degrees of freedom
Null hypothesis probability = 0.791
Photon flux (15-150 keV) in 701.2 sec: 9.149559E-02 ( -0.00797463 0.00802415 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.34228e-06 ( -1.98306e-07 1.98475e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -28.968 sec. to 672.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.86212 ( )
Epeak [keV] : 1.69752 ( )
Norm@50keV : 5.489315E-03 ( -1.462231E-03 2.112886E-03) )
------------------------------------------------------------
Chi-Squared = 50.15121 using 59 PHA bins.
Reduced chi-squared = 0.8955573 for 56 degrees of freedom
Null hypothesis probability = 0.695
Photon flux (15-150 keV) in 701.2 sec: 9.143826E-02 ( -0.00796853 0.00801737 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.34149e-06 ( -1.97907e-07 1.98832e-07 ) ergs/cm2
Band function
Time interval is from -28.968 sec. to 672.184 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.45933 ( -0.285731 0.265418 )
beta : -7.47013 ( -2.52987 17.4333 )
Epeak [keV] : 9.50776 ( -9.40776 6.66512 )
Norm@50keV : 3.802672E-03 ( -7.470324E-02 115.133 )
------------------------------------------------------------
Chi-Squared = 73.30212 using 59 PHA bins.
Reduced chi-squared = 1.332766 for 55 degrees of freedom
Null hypothesis probability = 5.008E-02
Photon flux (15-150 keV) in 701.2 sec: 9.069664E-02 ( -0.00813504 0.00749259 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.26707e-06 ( -2.33058e-07 2.24573e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -28.968 sec. to -28.016 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.85516 ( -0.909047 1.26705 )
Norm@50keV : 2.478767E-03 ( -2.478767E-03 2.210078E-03) )
------------------------------------------------------------
Chi-Squared = 58.00449 using 59 PHA bins.
Reduced chi-squared = 1.017623 for 57 degrees of freedom
Null hypothesis probability = 0.438
Photon flux (15-150 keV) in 0.9520 sec: 0.614845 ( -0.238879 0.239651 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.6624e-08 ( -1.26894e-08 1.54048e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -28.968 sec. to -28.016 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.95156 ( -0.889227 1.96197 )
Epeak [keV] : 1.31772 ( )
Norm@50keV : 1.238882E-02 ( )
------------------------------------------------------------
Chi-Squared = 58.28772 using 59 PHA bins.
but latest trial 1.06233 gives Chi-Squared = 8.92389
but latest trial -3.41199 gives Chi-Squared = 5.65681
Reduced chi-squared = 1.040852 for 56 degrees of freedom
Null hypothesis probability = 0.391
Photon flux (15-150 keV) in 0.9520 sec: 0.614563 ( -0.238799 0.239575 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.66088e-08 ( -1.26855e-08 1.54115e-08 ) ergs/cm2
Band function
Time interval is from -28.968 sec. to -28.016 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.92077 ( -9.28221 5.71779 )
beta : -7.90575 ( -6.67926 1.27969 )
Epeak [keV] : 8.53111 ( -11.9743 16.0982 )
Norm@50keV : 5.807984E-03 ( -8.000000E-02 16860.3 )
------------------------------------------------------------
Chi-Squared = 59.42583 using 59 PHA bins.
Reduced chi-squared = 1.080470 for 55 degrees of freedom
Null hypothesis probability = 0.318
Photon flux (15-150 keV) in 0.9520 sec: 0.614561 ( -0.238796 0.239575 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.31955e-08 ( -8.7723e-09 7.54441e-09 ) ergs/cm2
Plot creation:
Fri Apr 25 14:57:58 EDT 2008