batgrbproduct Analysis for Trigger=324561
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): Sat Sep 13 11:43:41 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger324561/GCN5_download_cron
======================================================================
Trigger: 00324561 Segment: 000
BAT Trigger Time: 242981217.216 [s; MET]
Trigger Stop: 242981218.24 [s; MET]
UTC: 2008-09-13T06:46:54.122140 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 65.7245690715967 Dec: -25.1102227127259 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.39
Image Trigger?: NO
Rate S/N Ratio: 13.9283882771841 [ if not an image trigger ]
Image S/N Ratio: 9.39
Flight Position: [ source = BAT ]
RA: 65.7245690715967 Dec: -25.1102227127259 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 65.7415501163352 Dec: -25.1274515691901 [deg; J2000]
{ 04h 22m 58.0s , -25d 07' 38.8" }
+/- 1.45970225730563 [arcmin] (estimated 90% radius based on SNR)
+/- 0.555924828439149 [arcmin] (formal 1-sigma fit error)
SNR: 17.7196493458669
Angular difference between Flight and Ground position is 1.385504 arcmin
Partial Coding Fraction: 0.390625 [ including projection effects ]
Duration
T90: 7.89200001955032 +/- 0.886530314915268
Measured from: -3.27599990367889
to: 4.61600011587143 [s; relative to TRIGTIME]
T50: 3.3120000064373 +/- 1.22353258263039
Measured from: -1.5919998884201
to: 1.7200001180172 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.108000010251999
to: 1.108000010252 [s; relative to TRIGTIME]
Total Fluence
Measured from: -3.77599999308586
to: 5.15600001811981 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.173958 0.292594 0.279204 0.068624
0.025132 0.026336 0.024367 0.020274 [error]
Peak 0.033545 0.059513 0.049924 0.017187
0.008673 0.009114 0.008853 0.006964 [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 6.69e-08 1.34e-07 2.09e-07 7.17e-07 5.82e-07 1.13e-06 erg/cm2
Error 1.13e-08 1.40e-08 2.27e-08 1.67e-07 5.75e-08 1.82e-07 erg/cm2
Peak flux Power-law 4.52e-01 4.57e-01 3.26e-01 3.69e-01 1.38e+00 1.60e+00 ph/cm2/s
Error 1.30e-01 8.48e-02 6.83e-02 1.54e-01 2.43e-01 2.78e-01 ph/cm2/s
Fluence Cutoff-PL 5.51e-08 1.44e-07 2.28e-07 2.67e-07 5.61e-07 6.89e-07 erg/cm2
Error 1.37e-08 1.66e-08 2.76e-08 1.92e-07 6.05e-08 1.96e-07 erg/cm2
Peak flux Cutoff-PL 3.85e-01 5.00e-01 3.53e-01 1.56e-01 1.34e+00 1.39e+00 ph/cm2/s
Error 1.54e-01 1.05e-01 8.23e-02 2.33e-01 2.49e-01 3.25e-01 ph/cm2/s
Fluence Band 5.45e-08 1.44e-07 2.28e-07 2.66e-07 5.60e-07 7.22e-07 erg/cm2
Error 1.35e-08 1.66e-08 2.76e-08 1.92e-07 6.04e-08 2.77e-07 erg/cm2
Peak flux Band 3.73e-01 5.25e-01 3.24e-01 2.87e-01 1.35e+00 1.48e+00 ph/cm2/s
Error 1.61e-01 1.11e-01 7.45e-02 2.39e-01 2.49e-01 3.20e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.360 0.152 - - 6.69e-03 6.19e-04 44.600 57
CPL 0.461 0.704 93.6 58.1 1.76e-02 1.48e-02 38.682 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.490 0.280 - - 1.11e-02 1.93e-03 54.639 57
CPL 0.579 1.335 78.4 4972.1 3.20e-02 1.00e-01 52.892 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: 7.296000 sec.
T50 in the 50-300 keV band: 3.840000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 8.932 -3.776 5.156
T90 7.892 -3.276 4.616
T50 3.312 -1.592 1.720
Peak 1.000 0.108 1.108
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
65.7416 -25.1275 0.0108 46.3 -168.2 0.8825 17.7 TRIG_00324561
------------------------------------------
Foreground time interval of the image:
-3.776 5.156 (delta_t = 8.932 [sec])
Background time interval of the image:
-239.216 -3.776 (delta_t = 235.440 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -3.776 sec. to 5.156 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.35968 ( -0.152485 0.151669 )
Norm@50keV : 6.689748E-03 ( -6.193682E-04 6.193956E-04) )
------------------------------------------------------------
Chi-Squared = 44.60033 using 59 PHA bins.
Reduced chi-squared = 0.7824619 for 57 degrees of freedom
Null hypothesis probability = 0.884
Photon flux (15-150 keV) in 8.932 sec: 0.807546 ( -0.078753 0.079026 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.82386e-07 ( -5.73515e-08 5.75766e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.776 sec. to 5.156 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.461090 ( -0.760201 0.647864 )
Epeak [keV] : 93.6306 ( -21.2104 94.9420 )
Norm@50keV : 1.759352E-02 ( -8.669028E-03 2.095215E-02) )
------------------------------------------------------------
Chi-Squared = 38.68186 using 59 PHA bins.
Reduced chi-squared = 0.6907476 for 56 degrees of freedom
Null hypothesis probability = 0.962
Photon flux (15-150 keV) in 8.932 sec: 0.778749 ( -0.081261 0.081593 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.60899e-07 ( -6.05599e-08 6.04143e-08 ) ergs/cm2
Band function
Time interval is from -3.776 sec. to 5.156 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.461919 ( -0.647020 0.736209 )
beta : -8.45806 ( -1.54194 7.01074 )
Epeak [keV] : 93.6592 ( -21.2578 95.0126 )
Norm@50keV : 1.757727E-02 ( -8.653752E-03 2.098170E-02) )
------------------------------------------------------------
Chi-Squared = 38.68191 using 59 PHA bins.
Reduced chi-squared = 0.7033074 for 55 degrees of freedom
Null hypothesis probability = 0.953
Photon flux (15-150 keV) in 8.932 sec: 0.778791 ( -0.081306 0.081551 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.60489e-07 ( -6.04294e-08 6.04294e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.108 sec. to 1.108 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.49040 ( -0.277392 0.282385 )
Norm@50keV : 1.107965E-02 ( -1.936415E-03 1.927053E-03) )
------------------------------------------------------------
Chi-Squared = 54.63896 using 59 PHA bins.
Reduced chi-squared = 0.9585782 for 57 degrees of freedom
Null hypothesis probability = 0.564
Photon flux (15-150 keV) in 1.000 sec: 1.37965 ( -0.2431 0.24385 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.05285e-07 ( -1.9687e-08 1.9869e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.108 sec. to 1.108 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.579390 ( -1.59400 1.07567 )
Epeak [keV] : 78.3978 ( -22.4944 9921.60 )
Norm@50keV : 3.202438E-02 ( -3.202438E-02 0.168961 )
------------------------------------------------------------
Chi-Squared = 52.89182 using 59 PHA bins.
but latest trial 39.4067 gives Chi-Squared = 9.94138
Reduced chi-squared = 0.9444968 for 56 degrees of freedom
Null hypothesis probability = 0.593
Photon flux (15-150 keV) in 1.000 sec: 1.34075 ( -0.24897 0.24915 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.99951e-08 ( -2.137e-08 2.14459e-08 ) ergs/cm2
Band function
Time interval is from 0.108 sec. to 1.108 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.208721E-02 ( -14.1070 0.893000 )
beta : -2.02350 ( -0.493265 0.422645 )
Epeak [keV] : 59.1111 ( -35.5186 420.747 )
Norm@50keV : 7.255076E-02 ( -136.862 34.8276 )
------------------------------------------------------------
Chi-Squared = 52.45507 using 59 PHA bins.
Reduced chi-squared = 0.9537286 for 55 degrees of freedom
Null hypothesis probability = 0.572
Photon flux (15-150 keV) in 1.000 sec: 1.34602 ( -0.25488 0.24325 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0243e-07 ( -1.99399e-08 1.93e-08 ) ergs/cm2
Plot creation:
Sat Sep 13 12:00:43 EDT 2008