batgrbproduct Analysis for Trigger=150823
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 8 16:38:36 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger150823/GCN5_download_cron
======================================================================
Trigger: 00150823 Segment: 000
BAT Trigger Time: 145973997.696 [s; MET]
Trigger Stop: 145973999.744 [s; MET]
UTC: 2005-08-17T12:19:58.016700 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 285.027947181705 Dec: -24.929880497601 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 33664
Image Trigger?: NO
Rate S/N Ratio: 12.2474487139159 [ if not an image trigger ]
Image S/N Ratio: 33664
Flight Position: [ source = BAT ]
RA: 285.027947181705 Dec: -24.929880497601 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 285.00587559829 Dec: -24.8898829334726 [deg; J2000]
{ 19h 00m 01.4s , -24d 53' 23.6" }
+/- 2.57817268018576 [arcmin] (estimated 90% radius based on SNR)
+/- 1.15568256034197 [arcmin] (formal 1-sigma fit error)
SNR: 7.86194145785221
RA = 19h 0m 1.4s (285.005876 deg.)
Dec = -24d 53' 24" (-24.889883 deg.)
Angular difference between Flight and Ground position is 2.683642 arcmin
Partial Coding Fraction: 0.46875 [ including projection effects ]
Duration
T90: 12.4160000085831 +/- 1.36065865436334
Measured from: -10.3920000195503
to: 2.02399998903275 [s; relative to TRIGTIME]
T50: 5.69600000977516 +/- 3.096733762019
Measured from: -5.0160000026226
to: 0.680000007152557 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.531999975442886
to: 1.53199997544289 [s; relative to TRIGTIME]
Total Fluence
Measured from: -11.3519999980927
to: 2.59999999403954 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.374582 0.070017 0.018673 0.017572
0.030560 0.028037 0.023639 0.019785 [error]
Peak 0.060231 0.017767 0.008359 -0.001572
0.008625 0.007683 0.006260 0.005330 [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 1.29e-07 3.65e-08 5.55e-09 9.61e-10 1.72e-07 1.72e-07 erg/cm2
Error 2.20e-08 1.56e-08 5.55e-09 1.98e-09 3.33e-08 3.37e-08 erg/cm2
Peak flux Power-law 6.85e-01 2.04e-01 3.31e-02 6.18e-03 9.26e-01 9.27e-01 ph/cm2/s
Error 1.70e-01 8.42e-02 3.00e-02 1.12e-02 2.25e-01 2.26e-01 ph/cm2/s
Fluence Cutoff-PL 1.29e-07 3.64e-08 5.53e-09 9.52e-10 1.72e-07 1.72e-07 erg/cm2
Error 2.20e-08 1.56e-08 5.54e-09 1.97e-09 3.33e-08 3.37e-08 erg/cm2
Peak flux Cutoff-PL 7.53e-01 1.45e-01 5.47e-04 1.82e-09 9.00e-01 9.23e-01 ph/cm2/s
Error 2.00e-01 1.06e-01 3.15e-02 7.21e-03 2.11e-01 2.27e-01 ph/cm2/s
Fluence Band 1.29e-07 3.56e-08 5.27e-09 8.82e-10 1.71e-07 1.69e-07 erg/cm2
Error 2.33e-08 1.32e-08 4.62e-09 1.02e-09 3.28e-08 3.09e-08 erg/cm2
Peak flux Band 7.16e-01 1.89e-01 1.72e-02 1.70e-03 9.30e-01 9.26e-01 ph/cm2/s
Error 1.82e-01 9.34e-02 2.97e-02 8.77e-03 2.25e-01 2.33e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 4.718 0.781 - - 3.18e-04 3.12e-04 49.495 57
CPL 1.837 0.000 1.2 3.7 7.36e-02 2.08e+02 50.206 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.621 0.784 - - 2.07e-03 1.88e-03 60.373 57
CPL 1.392 0.000 6.0 0.0 1.32e-01 0.00e+00 59.973 56
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 13.952 -11.352 2.600
T90 12.416 -10.392 2.024
T50 5.696 -5.016 0.680
Peak 1.000 0.532 1.532
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
285.0059 -24.8899 0.0243 35.1 154.6 0.4697 7.9 TRIG_00150823
------------------------------------------
Foreground time interval of the image:
-11.352 2.600 (delta_t = 13.952 [sec])
Background time interval of the image:
-60.696 -52.162 (delta_t = 8.534 [sec])
-50.696 -11.352 (delta_t = 39.344 [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 -11.352 sec. to 2.600 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.71822 ( -0.720384 0.842444 )
Norm@50keV : 3.175541E-04 ( -3.175541E-04 3.064173E-04) )
------------------------------------------------------------
Chi-Squared = 49.49467 using 59 PHA bins.
Reduced chi-squared = 0.8683276 for 57 degrees of freedom
Null hypothesis probability = 0.750
Photon flux (15-150 keV) in 13.95 sec: 0.375465 ( -0.063474 0.063526 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71875e-07 ( -3.25374e-08 3.40743e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -11.352 sec. to 2.600 sec.
Epeak [keV] : 1.19273 ( -0.555017 6.93068 )
Norm@50keV : 7.358861E-02 ( -6.480484E-02 415.560 )
------------------------------------------------------------
Chi-Squared = 50.20633 using 59 PHA bins.
but latest trial 0.849008 gives Chi-Squared = 63.9346
but latest trial -2.95626 gives Chi-Squared = 47.6906
but latest trial 7.64718 gives Chi-Squared = 0.634434
but latest trial 416.990 gives Chi-Squared = 4.90690
Reduced chi-squared = 0.8965417 for 56 degrees of freedom
Null hypothesis probability = 0.693
Photon flux (15-150 keV) in 13.95 sec: 0.375159 ( -0.063434 0.063486 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71833e-07 ( -3.25281e-08 3.40868e-08 ) ergs/cm2
Band function
Time interval is from -11.352 sec. to 2.600 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.66819 ( -7.25707 0.537369 )
beta : -9.01904 ( -0.844253 14.7163 )
Epeak [keV] : 8.79194 ( -8.69194 9991.21 )
Norm@50keV : 8.040452E-03 ( -1.34848 56.4638 )
------------------------------------------------------------
Chi-Squared = 74.42673 using 59 PHA bins.
Reduced chi-squared = 1.353213 for 55 degrees of freedom
Null hypothesis probability = 4.161E-02
Photon flux (15-150 keV) in 13.95 sec: 0.375159 ( -0.063434 0.063485 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71023e-07 ( -3.50338e-08 3.05156e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.552 sec. to 1.512 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.62112 ( -0.687268 0.881420 )
Norm@50keV : 2.072085E-03 ( -2.072085E-03 1.696115E-03) )
------------------------------------------------------------
Chi-Squared = 60.37276 using 59 PHA bins.
Reduced chi-squared = 1.059171 for 57 degrees of freedom
Null hypothesis probability = 0.355
Photon flux (15-150 keV) in 0.9600 sec: 0.925518 ( -0.22424 0.224952 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.37771e-08 ( -9.84499e-09 1.09567e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.552 sec. to 1.512 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39153 ( )
Epeak [keV] : 6.02676 ( )
Norm@50keV : 0.131960 ( )
------------------------------------------------------------
Chi-Squared = 59.97306 using 59 PHA bins.
Reduced chi-squared = 1.070947 for 56 degrees of freedom
Null hypothesis probability = 0.334
Photon flux (15-150 keV) in 0.9600 sec: 0.900258 ( -0.210594 0.211732 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.87701e-08 ( -7.48013e-09 1.34886e-08 ) ergs/cm2
Band function
Time interval is from 0.552 sec. to 1.512 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.68755 ( -3.63292 3.55228 )
beta : -9.33781 ( -0.881131 13.6212 )
Epeak [keV] : 12.6938 ( -12.5938 9987.31 )
Norm@50keV : 1.533665E-02 ( -0.168530 0.230498 )
------------------------------------------------------------
Chi-Squared = 68.77831 using 59 PHA bins.
Reduced chi-squared = 1.250515 for 55 degrees of freedom
Null hypothesis probability = 0.100
Photon flux (15-150 keV) in 0.9600 sec: 0.929790 ( -0.224939 0.22424 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.0596e-08 ( -8.51376e-09 1.15825e-08 ) ergs/cm2
Plot creation:
Tue Jan 8 16:49:30 EST 2008