batgrbproduct Analysis for Trigger=294974
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): Fri Dec 14 21:12:52 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger294974/GCN5_download_cron
======================================================================
Trigger: 00294974 Segment: 000
BAT Trigger Time: 214652496 [s; MET]
Trigger Stop: 214652560 [s; MET]
UTC: 2007-10-21T09:41:33.693520 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 340.635921111961 Dec: 23.70672778378 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.96
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.96
Flight Position: [ source = BAT ]
RA: 340.635921111961 Dec: 23.70672778378 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 340.58111263444 Dec: 23.7600967363862 [deg; J2000]
{ 22h 42m 19.5s , +23d 45' 36.3" }
+/- 3.3653589200311 [arcmin] (estimated 90% radius based on SNR)
+/- 1.89047603877462 [arcmin] (formal 1-sigma fit error)
SNR: 5.37299449411372
RA = 22h 42m 19.5s (340.581113 deg.)
Dec = 23d 45' 36" (23.760097 deg.)
Angular difference between Flight and Ground position is 4.395014 arcmin
Partial Coding Fraction: 0.78125 [ including projection effects ]
Duration
T90: 222.447999984026 +/- 76.4063336711012
Measured from: -15.3319999873638
to: 207.115999996662 [s; relative to TRIGTIME]
T50: 33.3880000114441 +/- 23.8243718195913
Measured from: 56.636000007391
to: 90.0240000188351 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 87.3039999902248
to: 88.3039999902248 [s; relative to TRIGTIME]
Total Fluence
Measured from: -33.5760000050068
to: 221.212000012398 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.753811 0.864694 0.490249 0.127265
0.078258 0.079131 0.071370 0.064051 [error]
Peak 0.021480 0.028582 0.025368 0.005995
0.005117 0.005336 0.004962 0.004191 [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 2.20e-07 3.52e-07 4.25e-07 1.00e-06 1.29e-06 2.00e-06 erg/cm2
Error 3.65e-08 3.72e-08 7.06e-08 3.45e-07 1.63e-07 4.10e-07 erg/cm2
Peak flux Power-law 1.97e-01 2.11e-01 1.61e-01 1.99e-01 6.45e-01 7.68e-01 ph/cm2/s
Error 6.98e-02 4.46e-02 4.08e-02 1.09e-01 1.26e-01 1.56e-01 ph/cm2/s
Fluence Cutoff-PL 2.15e-07 3.63e-07 4.26e-07 6.71e-07 1.26e-06 1.67e-06 erg/cm2
Error 4.03e-08 4.73e-08 7.39e-08 4.37e-07 1.83e-07 6.23e-07 erg/cm2
Peak flux Cutoff-PL 1.97e-01 2.11e-01 1.61e-01 1.98e-01 6.44e-01 7.66e-01 ph/cm2/s
Error 6.97e-02 4.46e-02 4.08e-02 1.08e-01 1.26e-01 1.50e-01 ph/cm2/s
Fluence Band 2.18e-07 3.58e-07 4.18e-07 7.85e-07 1.23e-06 1.93e-06 erg/cm2
Error 4.34e-08 4.50e-08 7.86e-08 3.66e-07 1.55e-07 6.28e-07 erg/cm2
Peak flux Band 1.88e-01 2.10e-01 1.62e-01 2.05e-01 6.43e-01 7.75e-01 ph/cm2/s
Error 4.86e-02 7.21e-02 2.50e-02 4.47e-01 1.24e-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 1.730 0.198 - - 5.46e-04 6.58e-05 74.298 57
CPL 1.278 0.000 72.1 4990.4 9.65e-04 5.45e-04 74.271 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.396 0.368 - - 5.30e-03 1.05e-03 46.423 57
CPL 1.368 1.808 994.3 0.0 5.50e-03 1.04e-02 46.452 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: 7.232000 sec.
T50 in the 50-300 keV band: 4.608000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 254.788 -33.576 221.212
T90 222.448 -15.332 207.116
T50 33.388 56.636 90.024
Peak 1.000 87.304 88.304
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
340.5811 +23.7601 0.0356 19.7 -110.3 0.6754 5.4 TRIG_00294974
------------------------------------------
Foreground time interval of the image:
-33.576 69.901 (delta_t = 103.477 [sec])
Background time interval of the image:
-239.000 -33.576 (delta_t = 205.424 [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 -33.576 sec. to 221.212 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.73028 ( -0.195536 0.201241 )
Norm@50keV : 5.462752E-04 ( -6.645921E-05 6.511464E-05) )
------------------------------------------------------------
Chi-Squared = 74.29836 using 59 PHA bins.
Reduced chi-squared = 1.303480 for 57 degrees of freedom
Null hypothesis probability = 6.162E-02
Photon flux (15-150 keV) in 254.8 sec: 7.333615E-02 ( -0.00777349 0.0077774 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28608e-06 ( -1.61874e-07 1.64713e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -33.576 sec. to 221.212 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.27808 ( )
Epeak [keV] : 72.0896 ( -97.1902 9883.64 )
Norm@50keV : 9.651531E-04 ( -3.205401E-04 7.699038E-04) )
------------------------------------------------------------
Chi-Squared = 74.27074 using 59 PHA bins.
but latest trial 23.4163 gives Chi-Squared = 1.84817
but latest trial 2.030667E-03 gives Chi-Squared = 244.606
Reduced chi-squared = 1.326263 for 56 degrees of freedom
Null hypothesis probability = 5.162E-02
Photon flux (15-150 keV) in 254.8 sec: 7.266653E-02 ( -0.00805001 0.00802842 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.25738e-06 ( -1.86065e-07 1.80691e-07 ) ergs/cm2
Band function
Time interval is from -33.576 sec. to 221.212 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.22284 ( -8.77716 5.48872 )
beta : -1.82065 ( -8.17935 0.275779 )
Epeak [keV] : 51.3616 ( -31.2616 1454.23 )
Norm@50keV : 1.159252E-03 ( -15.6055 79.2980 )
------------------------------------------------------------
Chi-Squared = 74.00333 using 59 PHA bins.
Reduced chi-squared = 1.345515 for 55 degrees of freedom
Null hypothesis probability = 4.464E-02
Photon flux (15-150 keV) in 254.8 sec: 7.266582E-02 ( -0.00806703 0.00804082 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.2315e-06 ( -1.36346e-07 1.74156e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 87.304 sec. to 88.304 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39565 ( -0.365424 0.371323 )
Norm@50keV : 5.297600E-03 ( -1.059798E-03 1.042734E-03) )
------------------------------------------------------------
Chi-Squared = 46.42333 using 59 PHA bins.
Reduced chi-squared = 0.8144444 for 57 degrees of freedom
Null hypothesis probability = 0.840
Photon flux (15-150 keV) in 1.000 sec: 0.644514 ( -0.125841 0.126212 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.1223e-08 ( -1.14875e-08 1.17481e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 87.304 sec. to 88.304 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.36792 ( -1.23588 2.38054 )
Epeak [keV] : 994.255 ( )
Norm@50keV : 5.496546E-03 ( -5.415284E-03 1.531149E-02) )
------------------------------------------------------------
Chi-Squared = 46.45242 using 59 PHA bins.
Reduced chi-squared = 0.8295075 for 56 degrees of freedom
Null hypothesis probability = 0.815
Photon flux (15-150 keV) in 1.000 sec: 0.644304 ( -0.125803 0.126174 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.12322e-08 ( -1.14923e-08 1.17528e-08 ) ergs/cm2
Band function
Time interval is from 87.304 sec. to 88.304 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.19154 ( -8.80846 6.19154 )
beta : -1.39565 ( -8.60435 0.365425 )
Epeak [keV] : 17.5675 ( -17.4675 9982.43 )
Norm@50keV : 1.065256E-02 ( -1.065256E-02 787.449 )
------------------------------------------------------------
Chi-Squared = 46.42334 using 59 PHA bins.
Reduced chi-squared = 0.8440607 for 55 degrees of freedom
Null hypothesis probability = 0.788
Photon flux (15-150 keV) in 1.000 sec: 0.643102 ( -0.123643 0.124871 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.1155e-08 ( -1.14575e-08 1.17719e-08 ) ergs/cm2
Plot creation:
Fri Dec 14 21:28:45 EST 2007