batgrbproduct Analysis for Trigger=146970
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): Mon Jan 7 16:58:21 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger146970/SDC
======================================================================
Trigger: 00146970 Segment: 000
BAT Trigger Time: 143612953.92 [s; MET]
Trigger Stop: 143612959.424 [s; MET]
UTC: 2005-07-21T04:29:14.287540 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 253.445004837197 Dec: -28.3896705827692 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.22
Image Trigger?: NO
Rate S/N Ratio: 15.0996688705415 [ if not an image trigger ]
Image S/N Ratio: 6.22
Flight Position: [ source = BAT ]
RA: 253.445004837197 Dec: -28.3896705827692 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 253.461055355825 Dec: -28.38832419309 [deg; J2000]
{ 16h 53m 50.7s , -28d 23' 18.0" }
+/- 2.06918474673001 [arcmin] (estimated 90% radius based on SNR)
+/- 0.820170009180595 [arcmin] (formal 1-sigma fit error)
SNR: 10.7640713576373
RA = 16h 53m 50.7s (253.461055 deg.)
Dec = -28d 23' 18" (-28.388324 deg.)
Angular difference between Flight and Ground position is 0.851060 arcmin
Partial Coding Fraction: 0.06445312 [ including projection effects ]
Duration
T90: 103.871999979019 +/- 46.2783163853342
Measured from: -0.647999972105026
to: 103.224000006914 [s; relative to TRIGTIME]
T50: 30.6879999935627 +/- 10.6199504618228
Measured from: 3.90800002217293
to: 34.5960000157356 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 2.00400000810623
to: 3.00400000810623 [s; relative to TRIGTIME]
Total Fluence
Measured from: -3.00399997830391
to: 149.436000019312 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.232562 2.486967 1.572248 0.309999
0.255634 0.228240 0.192787 0.161741 [error]
Peak 0.118516 0.121838 0.078735 0.029434
0.026722 0.024033 0.021644 0.014193 [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 7.74e-07 1.14e-06 1.25e-06 2.57e-06 3.94e-06 5.74e-06 erg/cm2
Error 1.27e-07 1.18e-07 1.85e-07 7.89e-07 4.39e-07 9.57e-07 erg/cm2
Peak flux Power-law 1.45e+00 8.85e-01 3.47e-01 1.82e-01 2.77e+00 2.86e+00 ph/cm2/s
Error 4.45e-01 2.11e-01 1.37e-01 1.31e-01 6.58e-01 6.73e-01 ph/cm2/s
Fluence Cutoff-PL 7.01e-07 1.23e-06 1.27e-06 9.39e-07 3.74e-06 4.19e-06 erg/cm2
Error 1.50e-07 1.57e-07 2.09e-07 1.17e-06 4.95e-07 1.31e-06 erg/cm2
Peak flux Cutoff-PL 1.25e+00 1.02e+00 3.82e-01 6.75e-02 2.71e+00 2.72e+00 ph/cm2/s
Error 5.23e-01 2.77e-01 1.77e-01 1.00e-01 6.65e-01 5.06e-01 ph/cm2/s
Fluence Band 6.88e-07 1.24e-06 1.23e-06 1.67e-06 3.77e-06 4.83e-06 erg/cm2
Error 1.56e-07 1.62e-07 2.27e-07 1.47e-06 4.74e-07 1.61e-06 erg/cm2
Peak flux Band 1.25e+00 1.02e+00 3.82e-01 6.77e-02 2.71e+00 2.72e+00 ph/cm2/s
Error 5.17e-01 2.76e-01 1.77e-01 1.32e-01 6.66e-01 6.77e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.867 0.184 - - 2.82e-03 3.12e-04 63.634 57
CPL 1.129 0.872 54.8 4979.7 6.96e-03 1.12e-02 61.191 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.353 0.426 - - 1.54e-02 4.80e-03 59.260 57
CPL 1.163 1.290 32.5 26.9 6.92e-02 5.31e-01 57.445 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: 26.176000 sec.
T50 in the 50-300 keV band: 12.032000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 152.440 -3.004 149.436
T90 103.872 -0.648 103.224
T50 30.688 3.908 34.596
Peak 1.000 2.004 3.004
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
253.4611 -28.3883 0.0178 39.1 91.4 6.8097 10.8 TRIG_00146970
------------------------------------------
Foreground time interval of the image:
-3.004 122.685 (delta_t = 125.689 [sec])
Background time interval of the image:
-291.415 -3.004 (delta_t = 288.411 [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.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -3.004 sec. to 149.436 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.86690 ( -0.181321 0.186436 )
Norm@50keV : 2.815307E-03 ( -3.143863E-04 3.103602E-04) )
------------------------------------------------------------
Chi-Squared = 63.63424 using 59 PHA bins.
Reduced chi-squared = 1.116390 for 57 degrees of freedom
Null hypothesis probability = 0.254
Photon flux (15-150 keV) in 152.4 sec: 0.398468 ( -0.042457 0.04261 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.94355e-06 ( -4.36184e-07 4.41564e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.004 sec. to 149.436 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12863 ( -0.952430 0.791253 )
Epeak [keV] : 54.7565 ( -14.1968 9945.24 )
Norm@50keV : 6.963455E-03 ( -6.963455E-03 1.539312E-02) )
------------------------------------------------------------
Chi-Squared = 61.19067 using 59 PHA bins.
but latest trial 1.92198 gives Chi-Squared = 2.73017
Reduced chi-squared = 1.092691 for 56 degrees of freedom
Null hypothesis probability = 0.295
Photon flux (15-150 keV) in 152.4 sec: 0.385540 ( -0.044858 0.04488 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.73653e-06 ( -4.92603e-07 4.98257e-07 ) ergs/cm2
Band function
Time interval is from -3.004 sec. to 149.436 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.901177 ( -1.37257 4.10578 )
beta : -2.29806 ( -7.70194 0.494905 )
Epeak [keV] : 48.4693 ( -17.8785 580.742 )
Norm@50keV : 9.764692E-03 ( -9.764692E-03 109.267 )
------------------------------------------------------------
Chi-Squared = 60.84074 using 59 PHA bins.
Reduced chi-squared = 1.106195 for 55 degrees of freedom
Null hypothesis probability = 0.274
Photon flux (15-150 keV) in 152.4 sec: 0.384928 ( -0.045751 0.044032 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.77355e-06 ( -4.83169e-07 4.63936e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 2.004 sec. to 3.004 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.35258 ( -0.383817 0.468373 )
Norm@50keV : 1.540880E-02 ( -4.932614E-03 4.674074E-03) )
------------------------------------------------------------
Chi-Squared = 59.25997 using 59 PHA bins.
Reduced chi-squared = 1.039649 for 57 degrees of freedom
Null hypothesis probability = 0.393
Photon flux (15-150 keV) in 1.000 sec: 2.77388 ( -0.65799 0.6589 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.48779e-07 ( -3.871e-08 3.9403e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.004 sec. to 3.004 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16313 ( -2.11087 0.468869 )
Epeak [keV] : 32.4656 ( -32.4556 21.4070 )
Norm@50keV : 6.916161E-02 ( -6.916161E-02 0.992661 )
------------------------------------------------------------
Chi-Squared = 57.44509 using 59 PHA bins.
but latest trial 2.06252 gives Chi-Squared = 3.32550
Reduced chi-squared = 1.025805 for 56 degrees of freedom
Null hypothesis probability = 0.421
Photon flux (15-150 keV) in 1.000 sec: 2.71323 ( -0.66652 0.66443 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.4669e-07 ( -3.8649e-08 3.9869e-08 ) ergs/cm2
Band function
Time interval is from 2.004 sec. to 3.004 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.25429 ( -8.74571 2.14599 )
beta : -8.93646 ( -1.06354 6.81034 )
Epeak [keV] : 31.3611 ( -31.2611 22.5345 )
Norm@50keV : 6.181292E-02 ( -6.181291E-02 0.999896 )
------------------------------------------------------------
Chi-Squared = 57.45163 using 59 PHA bins.
Reduced chi-squared = 1.044575 for 55 degrees of freedom
Null hypothesis probability = 0.384
Photon flux (15-150 keV) in 1.000 sec: 2.71324 ( -0.66655 0.66535 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.464e-07 ( -3.8218e-08 3.9943e-08 ) ergs/cm2
Plot creation:
Mon Jan 7 17:14:32 EST 2008