batgrbproduct Analysis for Trigger=309096
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 Apr 13 18:37:33 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger309096/GCN5_download_cron
======================================================================
Trigger: 00309096 Segment: 000
BAT Trigger Time: 229748062.016 [s; MET]
Trigger Stop: 229748062.528 [s; MET]
UTC: 2008-04-13T02:54:19.302440 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 287.289929388104 Dec: -27.679225960068 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.06
Image Trigger?: NO
Rate S/N Ratio: 15.6524758424985 [ if not an image trigger ]
Image S/N Ratio: 9.06
Flight Position: [ source = BAT ]
RA: 287.289929388104 Dec: -27.679225960068 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 287.300600796074 Dec: -27.6769415457002 [deg; J2000]
{ 19h 09m 12.1s , -27d 40' 37.0" }
+/- 0.636977592527491 [arcmin] (estimated 90% radius based on SNR)
+/- 0.183173311790275 [arcmin] (formal 1-sigma fit error)
SNR: 57.9350005720869
RA = 19h 9m 12.1s (287.300601 deg.)
Dec = -27d 40' 37" (-27.676942 deg.)
Angular difference between Flight and Ground position is 0.583349 arcmin
Partial Coding Fraction: 0.8125 [ including projection effects ]
Duration
T90: 46.3519999980927 +/- 0.470472123802958
Measured from: 1.11599999666214
to: 47.4679999947548 [s; relative to TRIGTIME]
T50: 15.391999989748 +/- 0.75705748169605
Measured from: 2.84000000357628
to: 18.2319999933243 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.64399999380112
to: 2.64399999380112 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0879999995231628
to: 50.33599999547 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.594520 2.166045 1.511170 0.325071
0.046637 0.043395 0.039150 0.036815 [error]
Peak 0.137024 0.258331 0.235163 0.059347
0.008437 0.008917 0.008617 0.006337 [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 5.01e-07 8.86e-07 1.20e-06 3.33e-06 3.47e-06 5.92e-06 erg/cm2
Error 2.91e-08 2.85e-08 4.19e-08 2.77e-07 9.99e-08 2.96e-07 erg/cm2
Peak flux Power-law 1.44e+00 1.75e+00 1.54e+00 2.33e+00 5.55e+00 7.06e+00 ph/cm2/s
Error 1.19e-01 8.67e-02 6.90e-02 2.28e-01 2.33e-01 2.93e-01 ph/cm2/s
Fluence Cutoff-PL 4.84e-07 8.94e-07 1.21e-06 2.67e-06 3.43e-06 5.11e-06 erg/cm2
Error 3.88e-08 3.06e-08 4.60e-08 7.64e-07 1.15e-07 7.83e-07 erg/cm2
Peak flux Cutoff-PL 1.28e+00 1.79e+00 1.62e+00 1.53e+00 5.43e+00 6.23e+00 ph/cm2/s
Error 1.53e-01 9.40e-02 8.78e-02 4.12e-01 2.44e-01 4.85e-01 ph/cm2/s
Fluence Band 4.78e-07 8.90e-07 1.21e-06 2.67e-06 3.43e-06 5.00e-06 erg/cm2
Error 3.65e-08 3.06e-08 4.60e-08 6.12e-07 1.17e-07 0.00e+00 erg/cm2
Peak flux Band 1.28e+00 1.79e+00 1.62e+00 1.53e+00 5.43e+00 6.23e+00 ph/cm2/s
Error 1.53e-01 9.40e-02 8.78e-02 4.12e-01 2.44e-01 4.85e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.566 0.056 - - 7.33e-03 2.00e-04 67.437 57
CPL 1.404 0.216 199.2 4943.7 8.70e-03 1.94e-03 66.003 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.186 0.072 - - 4.74e-02 1.89e-03 54.549 57
CPL 0.735 0.305 160.3 111.6 7.53e-02 2.35e-02 47.443 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: 44.736000 sec.
T50 in the 50-300 keV band: 14.720000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 50.424 -0.088 50.336
T90 46.352 1.116 47.468
T50 15.392 2.840 18.232
Peak 1.000 1.644 2.644
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
287.3006 -27.6769 0.0033 16.7 -90.6 2.8470 57.9 TRIG_00309096
------------------------------------------
Foreground time interval of the image:
-0.088 10.085 (delta_t = 10.173 [sec])
Background time interval of the image:
-239.016 -0.088 (delta_t = 238.928 [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 -0.088 sec. to 50.336 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.56564 ( -5.614221E-02 5.616820E-02) )
Norm@50keV : 7.328139E-03 ( -2.002586E-04 2.002404E-04) )
------------------------------------------------------------
Chi-Squared = 67.43731 using 59 PHA bins.
Reduced chi-squared = 1.183111 for 57 degrees of freedom
Null hypothesis probability = 0.162
Photon flux (15-150 keV) in 50.42 sec: 0.931953 ( -0.029001 0.029146 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.47068e-06 ( -9.9635e-08 1.00069e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.088 sec. to 50.336 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.40435 ( -0.234147 0.198236 )
Epeak [keV] : 199.154 ( -86.5710 9800.85 )
Norm@50keV : 8.699793E-03 ( -1.492252E-03 2.387386E-03) )
------------------------------------------------------------
Chi-Squared = 66.00298 using 59 PHA bins.
Reduced chi-squared = 1.178625 for 56 degrees of freedom
Null hypothesis probability = 0.169
Photon flux (15-150 keV) in 50.42 sec: 0.919348 ( -0.033473 0.032302 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.42847e-06 ( -1.17746e-07 1.11832e-07 ) ergs/cm2
Band function
Time interval is from -0.088 sec. to 50.336 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.02216 ( -8.97784 2.38943 )
beta : -1.62672 ( -8.37328 9.025764E-02) )
Epeak [keV] : 69.5636 ( -69.4636 9893.77 )
Norm@50keV : 1.497268E-02 ( -1.497268E-02 973.467 )
------------------------------------------------------------
Chi-Squared = 64.89069 using 59 PHA bins.
Reduced chi-squared = 1.179831 for 55 degrees of freedom
Null hypothesis probability = 0.170
Photon flux (15-150 keV) in 50.42 sec: 0.910529 ( -0.03851 0.03642 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.42523e-06 ( -1.17675e-07 1.16833e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.644 sec. to 2.644 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.18605 ( -7.232070E-02 7.194173E-02) )
Norm@50keV : 4.736120E-02 ( -1.893573E-03 1.892805E-03) )
------------------------------------------------------------
Chi-Squared = 54.54914 using 59 PHA bins.
Reduced chi-squared = 0.9570024 for 57 degrees of freedom
Null hypothesis probability = 0.568
Photon flux (15-150 keV) in 1.000 sec: 5.54857 ( -0.233 0.23342 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.82462e-07 ( -2.0872e-08 2.0817e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.644 sec. to 2.644 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.735372 ( -0.315951 0.294010 )
Epeak [keV] : 160.331 ( -43.4881 179.776 )
Norm@50keV : 7.533137E-02 ( -1.923341E-02 2.786566E-02) )
------------------------------------------------------------
Chi-Squared = 47.44341 using 59 PHA bins.
Reduced chi-squared = 0.8472037 for 56 degrees of freedom
Null hypothesis probability = 0.785
Photon flux (15-150 keV) in 1.000 sec: 5.43183 ( -0.24391 0.24416 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.72937e-07 ( -2.2189e-08 2.2239e-08 ) ergs/cm2
Band function
Time interval is from 1.644 sec. to 2.644 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.735406 ( -0.293963 0.316053 )
beta : -8.96544 ( -1.03456 7.73953 )
Epeak [keV] : 160.332 ( -43.4764 179.370 )
Norm@50keV : 7.532276E-02 ( -1.922964E-02 2.788062E-02) )
------------------------------------------------------------
Chi-Squared = 47.44340 using 59 PHA bins.
Reduced chi-squared = 0.8626072 for 55 degrees of freedom
Null hypothesis probability = 0.756
Photon flux (15-150 keV) in 1.000 sec: 5.43198 ( -0.24408 0.24439 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.72767e-07 ( -2.2327e-08 2.206e-08 ) ergs/cm2
Plot creation:
Sun Apr 13 19:38:52 EDT 2008