batgrbproduct Analysis for Trigger=302888
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 Feb 10 21:19:33 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger302888/GCN5_download_cron
======================================================================
Trigger: 00302888 Segment: 000
BAT Trigger Time: 224322608 [s; MET]
Trigger Stop: 224322688 [s; MET]
UTC: 2008-02-10T07:50:05.435780 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 251.269750345052 Dec: 13.8302696590224 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 17.85
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 17.85
Flight Position: [ source = BAT ]
RA: 251.269750345052 Dec: 13.8302696590224 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 251.25853796541 Dec: 13.8262996978416 [deg; J2000]
{ 16h 45m 02.0s , +13d 49' 34.7" }
+/- 1.09251979962537 [arcmin] (estimated 90% radius based on SNR)
+/- 0.400064164317257 [arcmin] (formal 1-sigma fit error)
SNR: 26.8052188019137
RA = 16h 45m 2.0s (251.258538 deg.)
Dec = 13d 49' 35" (13.826300 deg.)
Angular difference between Flight and Ground position is 0.695317 arcmin
Partial Coding Fraction: 0.734375 [ including projection effects ]
Duration
T90: 45.2040000259876 +/- 10.6628934271791
Measured from: -10.2840000092983
to: 34.9200000166893 [s; relative to TRIGTIME]
T50: 11.7159999907017 +/- 2.30127357206699
Measured from: -0.00799998641014099
to: 11.7080000042915 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 4.50400000810623
to: 5.50400000810623 [s; relative to TRIGTIME]
Total Fluence
Measured from: -14.555999994278
to: 47.7199999988079 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.968380 1.114727 0.758388 0.222727
0.052105 0.053422 0.049685 0.049705 [error]
Peak 0.047831 0.064249 0.066900 0.017163
0.007146 0.007548 0.007221 0.006539 [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 3.18e-07 4.97e-07 5.84e-07 1.33e-06 1.79e-06 2.73e-06 erg/cm2
Error 3.24e-08 2.90e-08 5.07e-08 2.52e-07 1.15e-07 2.90e-07 erg/cm2
Peak flux Power-law 4.63e-01 5.15e-01 4.08e-01 5.36e-01 1.58e+00 1.92e+00 ph/cm2/s
Error 1.03e-01 6.81e-02 5.84e-02 1.65e-01 1.90e-01 2.33e-01 ph/cm2/s
Fluence Cutoff-PL 3.18e-07 4.97e-07 5.84e-07 1.32e-06 1.79e-06 2.72e-06 erg/cm2
Error 3.24e-08 2.90e-08 5.07e-08 2.50e-07 1.15e-07 2.88e-07 erg/cm2
Peak flux Cutoff-PL 4.63e-01 5.15e-01 4.08e-01 5.32e-01 1.58e+00 1.92e+00 ph/cm2/s
Error 1.03e-01 6.81e-02 5.85e-02 1.64e-01 1.90e-01 2.32e-01 ph/cm2/s
Fluence Band 3.21e-07 3.75e-06 4.42e-06 1.01e-05 1.35e-05 2.67e-06 erg/cm2
Error 3.13e-05 3.16e-05 6.48e-05 9.19e-05 1.70e-07 0.00e+00 erg/cm2
Peak flux Band 4.63e-01 5.15e-01 4.08e-01 5.32e-01 1.58e+00 1.92e+00 ph/cm2/s
Error 1.03e-01 6.81e-02 4.94e-02 1.78e-01 1.90e-01 3.05e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.766 0.116 - - 3.11e-03 1.92e-04 43.535 57
CPL 1.765 0.117 9996.6 5000.0 3.12e-03 1.93e-04 43.544 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.334 0.214 - - 1.32e-02 1.54e-03 42.870 57
CPL 1.258 1.050 510.4 0.0 1.44e-02 1.55e-03 42.909 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: 19.584000 sec.
T50 in the 50-300 keV band: 7.424000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 62.276 -14.556 47.720
T90 45.204 -10.284 34.920
T50 11.716 -0.008 11.708
Peak 1.000 4.504 5.504
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
251.2585 +13.8263 0.0072 32.6 -5.2 3.1176 26.8 TRIG_00302888
------------------------------------------
Foreground time interval of the image:
-14.556 47.720 (delta_t = 62.276 [sec])
Background time interval of the image:
-239.000 -14.556 (delta_t = 224.444 [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 -14.556 sec. to 47.720 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76630 ( -0.115194 0.116955 )
Norm@50keV : 3.112303E-03 ( -1.931034E-04 1.912082E-04) )
------------------------------------------------------------
Chi-Squared = 43.53500 using 59 PHA bins.
Reduced chi-squared = 0.7637718 for 57 degrees of freedom
Null hypothesis probability = 0.905
Photon flux (15-150 keV) in 62.28 sec: 0.423394 ( -0.025169 0.025316 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78706e-06 ( -1.14377e-07 1.15218e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -14.556 sec. to 47.720 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76528 ( -0.115805 0.117537 )
Epeak [keV] : 9996.56 ( -9996.55 3.44336 )
Norm@50keV : 3.116651E-03 ( -1.942585E-04 1.922958E-04) )
------------------------------------------------------------
Chi-Squared = 43.54424 using 59 PHA bins.
Reduced chi-squared = 0.7775756 for 56 degrees of freedom
Null hypothesis probability = 0.888
Photon flux (15-150 keV) in 62.28 sec: 0.423195 ( -0.025157 0.025305 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78693e-06 ( -1.14302e-07 1.15343e-07 ) ergs/cm2
Band function
Time interval is from -14.556 sec. to 47.720 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.43144 ( -8.56856 6.43144 )
beta : -1.76628 ( -0.117005 0.115157 )
Epeak [keV] : 16.3899 ( -16.2899 9983.61 )
Norm@50keV : 7.545741E-03 ( -7.545741E-03 42.4580 )
------------------------------------------------------------
Chi-Squared = 43.53500 using 59 PHA bins.
Reduced chi-squared = 0.7915455 for 55 degrees of freedom
Null hypothesis probability = 0.868
Photon flux (15-150 keV) in 62.28 sec: 6.51934 ( -6.51934 58.6561 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.35199e-05 ( -1.35199e-05 0.000170346 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 4.504 sec. to 5.504 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.33399 ( -0.213664 0.213414 )
Norm@50keV : 1.319359E-02 ( -1.542394E-03 1.539543E-03) )
------------------------------------------------------------
Chi-Squared = 42.86969 using 59 PHA bins.
Reduced chi-squared = 0.7520998 for 57 degrees of freedom
Null hypothesis probability = 0.917
Photon flux (15-150 keV) in 1.000 sec: 1.58431 ( -0.18934 0.18981 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.29256e-07 ( -1.6834e-08 1.7162e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.504 sec. to 5.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.25847 ( -0.770037 1.32937 )
Epeak [keV] : 510.424 ( )
Norm@50keV : 1.435353E-02 ( -1.551015E-03 1.547527E-03) )
------------------------------------------------------------
Chi-Squared = 42.90940 using 59 PHA bins.
Reduced chi-squared = 0.7662393 for 56 degrees of freedom
Null hypothesis probability = 0.901
Photon flux (15-150 keV) in 1.000 sec: 1.58382 ( -0.18928 0.18976 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.29332e-07 ( -1.6902e-08 1.7126e-08 ) ergs/cm2
Band function
Time interval is from 4.504 sec. to 5.504 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.07114 ( -8.92885 6.07048 )
beta : -1.33379 ( -8.66621 0.213597 )
Epeak [keV] : 40.6729 ( -40.5729 9959.33 )
Norm@50keV : 2.523855E-02 ( -1.191046E-02 140.481 )
------------------------------------------------------------
Chi-Squared = 42.86969 using 59 PHA bins.
Reduced chi-squared = 0.7794489 for 55 degrees of freedom
Null hypothesis probability = 0.883
Photon flux (15-150 keV) in 1.000 sec: 1.58382 ( -0.18928 0.18976 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.29178e-07 ( -1.6861e-08 1.7176e-08 ) ergs/cm2
Plot creation:
Sun Feb 10 21:46:40 EST 2008