batgrbproduct Analysis for Trigger=318101
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): Sun Jul 27 15:13:20 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger318101/GCN5_download_cron
======================================================================
Trigger: 00318101 Segment: 000
BAT Trigger Time: 238839207.932 [s; MET]
Trigger Stop: 238839207.996 [s; MET]
UTC: 2008-07-27T08:13:24.959660 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 276.869989337883 Dec: 1.17214157120085 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.73
Image Trigger?: NO
Rate S/N Ratio: 38.2230297072328 [ if not an image trigger ]
Image S/N Ratio: 10.73
Flight Position: [ source = BAT ]
RA: 276.869989337883 Dec: 1.17214157120085 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 276.870920644792 Dec: 1.17295696169464 [deg; J2000]
{ 18h 27m 29.0s , +01d 10' 22.6" }
+/- 0.638820707145399 [arcmin] (estimated 90% radius based on SNR)
+/- 0.182153494893965 [arcmin] (formal 1-sigma fit error)
SNR: 57.6963581770422
Angular difference between Flight and Ground position is 0.074260 arcmin
Partial Coding Fraction: 0.6875 [ including projection effects ]
Duration
T90: 8.62800002098083 +/- 0.153310150613681
Measured from: 0.0919999778270721
to: 8.71999999880791 [s; relative to TRIGTIME]
T50: 6.3120000064373 +/- 0.110634524953673
Measured from: 1
to: 7.3120000064373 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0400000214576721
to: 0.959999978542328 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.224000006914139
to: 9.39999997615814 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.823569 1.459705 1.538938 0.416558
0.026841 0.028153 0.027319 0.020326 [error]
Peak 0.171157 0.311187 0.368811 0.114831
0.009987 0.011359 0.011698 0.008591 [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 2.68e-07 6.21e-07 1.14e-06 5.03e-06 3.10e-06 6.05e-06 erg/cm2
Error 1.32e-08 1.80e-08 2.80e-08 2.92e-07 7.29e-08 0.00e+00 erg/cm2
Peak flux Power-law 1.65e+00 2.29e+00 2.34e+00 4.37e+00 7.68e+00 1.07e+01 ph/cm2/s
Error 1.34e-01 1.11e-01 9.36e-02 3.88e-01 2.96e-01 5.52e-01 ph/cm2/s
Fluence Cutoff-PL 2.44e-07 6.28e-07 1.18e-06 3.47e-06 3.07e-06 3.41e-06 erg/cm2
Error 1.77e-08 1.88e-08 3.53e-08 6.67e-07 3.82e-08 0.00e+00 erg/cm2
Peak flux Cutoff-PL 1.55e+00 2.31e+00 2.41e+00 3.50e+00 7.60e+00 9.77e+00 ph/cm2/s
Error 1.76e-01 1.16e-01 1.21e-01 8.98e-01 3.03e-01 8.80e-01 ph/cm2/s
Fluence Band 2.41e-07 6.26e-07 1.18e-06 3.46e-06 3.07e-06 3.18e-06 erg/cm2
Error 1.75e-08 1.88e-08 3.53e-08 6.90e-07 7.64e-08 0.00e+00 erg/cm2
Peak flux Band 1.55e+00 2.31e+00 2.41e+00 3.75e+00 7.59e+00 9.32e+00 ph/cm2/s
Error 1.82e-01 1.19e-01 1.22e-01 1.43e+00 3.14e-01 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.120 0.041 - - 3.11e-02 7.14e-04 54.125 57
CPL 0.800 0.174 227.2 119.2 4.22e-02 6.90e-03 43.576 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.967 0.067 - - 6.68e-02 2.53e-03 44.244 57
CPL 0.739 0.267 331.0 4908.9 8.35e-02 2.16e-02 42.050 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: 8.128000 sec.
T50 in the 50-300 keV band: 6.272000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 9.624 -0.224 9.400
T90 8.628 0.092 8.720
T50 6.312 1.000 7.312
Peak 1.000 -0.040 0.960
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
276.8709 +1.1730 0.0033 27.2 28.7 2.8020 57.7 TRIG_00318101
------------------------------------------
Foreground time interval of the image:
-0.224 6.769 (delta_t = 6.993 [sec])
Background time interval of the image:
-239.932 -0.224 (delta_t = 239.708 [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 -0.224 sec. to 9.400 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12030 ( -4.138768E-02 4.121101E-02) )
Norm@50keV : 3.105400E-02 ( -7.144641E-04 7.135198E-04) )
------------------------------------------------------------
Chi-Squared = 54.12532 using 59 PHA bins.
Reduced chi-squared = 0.9495670 for 57 degrees of freedom
Null hypothesis probability = 0.584
Photon flux (15-150 keV) in 9.624 sec: 3.60947 ( -0.08804 0.0882 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.10474e-06 ( -7.28441e-08 7.29018e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.224 sec. to 9.400 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.800277 ( -0.176738 0.170477 )
Epeak [keV] : 227.153 ( -59.0034 179.364 )
Norm@50keV : 4.223231E-02 ( -6.241307E-03 7.567611E-03) )
------------------------------------------------------------
Chi-Squared = 43.57648 using 59 PHA bins.
Reduced chi-squared = 0.7781515 for 56 degrees of freedom
Null hypothesis probability = 0.887
Photon flux (15-150 keV) in 9.624 sec: 3.54039 ( -0.09402 0.09439 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.06722e-06 ( -3.82939e-08 3.81977e-08 ) ergs/cm2
Band function
Time interval is from -0.224 sec. to 9.400 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.800503 ( -0.170262 0.177000 )
beta : -9.16424 ( -0.835760 4.89288 )
Epeak [keV] : 227.250 ( -59.1292 179.199 )
Norm@50keV : 4.222019E-02 ( -6.232329E-03 7.579096E-03) )
------------------------------------------------------------
Chi-Squared = 43.57640 using 59 PHA bins.
Reduced chi-squared = 0.7922983 for 55 degrees of freedom
Null hypothesis probability = 0.867
Photon flux (15-150 keV) in 9.624 sec: 3.54045 ( -0.09423 0.09467 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.06518e-06 ( -7.64819e-08 7.63376e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.040 sec. to 0.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.967258 ( -6.750381E-02 6.689811E-02) )
Norm@50keV : 6.677951E-02 ( -2.535813E-03 2.527967E-03) )
------------------------------------------------------------
Chi-Squared = 44.24406 using 59 PHA bins.
Reduced chi-squared = 0.7762116 for 57 degrees of freedom
Null hypothesis probability = 0.891
Photon flux (15-150 keV) in 1.000 sec: 7.67692 ( -0.29565 0.29597 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.30685e-07 ( -2.9601e-08 2.962e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.040 sec. to 0.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.739409 ( -0.280370 0.254289 )
Epeak [keV] : 331.013 ( -148.818 9668.99 )
Norm@50keV : 8.354712E-02 ( -1.758272E-02 2.555071E-02) )
------------------------------------------------------------
Chi-Squared = 42.04990 using 59 PHA bins.
Reduced chi-squared = 0.7508911 for 56 degrees of freedom
Null hypothesis probability = 0.917
Photon flux (15-150 keV) in 1.000 sec: 7.59925 ( -0.3001 0.3057 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.24655e-07 ( -3.0563e-08 3.0697e-08 ) ergs/cm2
Band function
Time interval is from -0.040 sec. to 0.960 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.810028 ( -9.18997 5.80849 )
beta : -0.967234 ( -6.691206E-02 6.749964E-02) )
Epeak [keV] : 53.1693 ( -393.775 9606.12 )
Norm@50keV : 0.106393 ( -1.422868E-02 1650.22 )
------------------------------------------------------------
Chi-Squared = 44.24406 using 59 PHA bins.
Reduced chi-squared = 0.8044375 for 55 degrees of freedom
Null hypothesis probability = 0.850
Photon flux (15-150 keV) in 1.000 sec: 7.59169 ( -0.31295 0.31426 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.24201e-07 ( -3.0859e-08 3.0638e-08 ) ergs/cm2
Plot creation:
Sun Jul 27 15:57:57 EDT 2008