batgrbproduct Analysis for Trigger=278987
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): Thu Dec 13 21:23:11 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger278987/GCN5_download_cron
======================================================================
Trigger: 00278987 Segment: 000
BAT Trigger Time: 200469402.112 [s; MET]
Trigger Stop: 200469403.136 [s; MET]
UTC: 2007-05-10T05:56:40.167020 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 343.01446523543 Dec: 47.9334129618286 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.53
Image Trigger?: NO
Rate S/N Ratio: 17.5783958312469 [ if not an image trigger ]
Image S/N Ratio: 6.53
Flight Position: [ source = BAT ]
RA: 343.01446523543 Dec: 47.9334129618286 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 343.017350843807 Dec: 47.9251075821523 [deg; J2000]
{ 22h 52m 04.2s , +47d 55' 30.4" }
+/- 3.99260232361829 [arcmin] (estimated 90% radius based on SNR)
+/- 1.86933313462705 [arcmin] (formal 1-sigma fit error)
SNR: 4.20902163697654
RA = 22h 52m 4.2s (343.017351 deg.)
Dec = 47d 55' 30" (47.925108 deg.)
Angular difference between Flight and Ground position is 0.511648 arcmin
Partial Coding Fraction: 0.890625 [ including projection effects ]
Duration
T90: 1.02400001883507 +/-
Measured from: 0
to: 1.02400001883507 [s; relative to TRIGTIME]
T50: 1.02400001883507 +/-
Measured from: 0
to: 1.02400001883507 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 1.02400001883507 second)
Measured from: 1.49011611938477e-08
to: 1.02400003373623 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 1.02400001883507 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.011667 0.036131 0.029705 -0.002082
0.007117 0.008177 0.008157 0.010350 [error]
Peak 0.011667 0.036131 0.029705 -0.002082
0.007117 0.008177 0.008157 0.010350 [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 4.69e-09 1.11e-08 2.11e-08 9.71e-08 5.73e-08 1.39e-07 erg/cm2
Error 2.48e-09 3.77e-09 7.65e-09 7.89e-08 1.99e-08 8.69e-08 erg/cm2
Peak flux Power-law 1.45e-01 1.89e-01 1.79e-01 3.01e-01 6.14e-01 8.14e-01 ph/cm2/s
Error 7.88e-02 6.54e-02 6.31e-02 2.22e-01 1.89e-01 2.83e-01 ph/cm2/s
Fluence Cutoff-PL 2.83e-09 1.33e-08 2.46e-08 1.18e-08 4.99e-08 5.22e-08 erg/cm2
Error 2.18e-09 5.20e-09 7.68e-09 4.96e-08 2.01e-08 5.43e-08 erg/cm2
Peak flux Cutoff-PL 8.66e-02 2.20e-01 2.15e-01 5.64e-02 5.68e-01 5.78e-01 ph/cm2/s
Error 8.00e-02 8.84e-02 8.45e-02 1.60e-01 1.89e-01 2.37e-01 ph/cm2/s
Fluence Band 3.17e-09 1.32e-08 2.46e-08 1.21e-08 5.00e-08 5.46e-08 erg/cm2
Error 1.99e-09 4.04e-09 8.32e-09 1.01e-08 1.58e-08 6.22e-08 erg/cm2
Peak flux Band 8.98e-02 2.20e-01 2.15e-01 5.63e-02 5.68e-01 5.83e-01 ph/cm2/s
Error 6.98e-02 6.81e-02 7.01e-02 6.35e-02 1.44e-01 2.11e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.075 0.507 - - 5.30e-03 1.62e-03 69.597 57
CPL -1.291 2.046 73.2 559.6 6.96e-02 1.48e-01 66.758 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.075 0.507 - - 5.30e-03 1.62e-03 69.597 57
CPL -1.291 2.046 73.2 559.6 6.96e-02 1.48e-01 66.758 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 1.024 0.000 1.024
T90 1.024 0.000 1.024
T50 1.024 0.000 1.024
Peak 1.024 0.000 1.024
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
343.0174 +47.9251 0.0455 24.8 -150.0 0.0775 4.2 TRIG_00278987
------------------------------------------
Foreground time interval of the image:
0.000 1.024 (delta_t = 1.024 [sec])
Background time interval of the image:
-78.911 -30.344 (delta_t = 48.567 [sec])
-29.112 -10.112 (delta_t = 19.000 [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 0.000 sec. to 1.024 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.07525 ( -0.515979 0.498446 )
Norm@50keV : 5.302926E-03 ( -1.623487E-03 1.623000E-03) )
------------------------------------------------------------
Chi-Squared = 69.59676 using 59 PHA bins.
Reduced chi-squared = 1.220996 for 57 degrees of freedom
Null hypothesis probability = 0.122
Photon flux (15-150 keV) in 1.024 sec: 0.613709 ( -0.188582 0.189024 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.73334e-08 ( -1.96023e-08 2.0201e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 1.024 sec.
Parameters : value lower 90% higher 90%
Photon index: -1.29105 ( -1.70895 2.38255 )
Epeak [keV] : 73.2411 ( -21.7430 1097.51 )
Norm@50keV : 6.961339E-02 ( -6.961340E-02 0.227345 )
------------------------------------------------------------
Chi-Squared = 66.75841 using 59 PHA bins.
but latest trial 41.0093 gives Chi-Squared = 7.54025
but latest trial 0.416817 gives Chi-Squared = 5.93253
Reduced chi-squared = 1.192114 for 56 degrees of freedom
Null hypothesis probability = 0.154
Photon flux (15-150 keV) in 1.024 sec: 0.568089 ( -0.184071 0.193963 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.9902e-08 ( -1.84861e-08 2.16208e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 1.024 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.09569 ( -1.82509 3.31242 )
beta : -9.01620 ( -0.983798 8.07375 )
Epeak [keV] : 75.5849 ( -48.8989 1229.88 )
Norm@50keV : 5.679850E-02 ( -3.393131E-02 0.132519 )
------------------------------------------------------------
Chi-Squared = 66.76771 using 59 PHA bins.
Reduced chi-squared = 1.213958 for 55 degrees of freedom
Null hypothesis probability = 0.133
Photon flux (15-150 keV) in 1.024 sec: 0.568002 ( -0.18864 0.100347 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.00475e-08 ( -1.59756e-08 1.55744e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 1.024 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.07525 ( -0.515979 0.498446 )
Norm@50keV : 5.302926E-03 ( -1.623487E-03 1.623000E-03) )
------------------------------------------------------------
Chi-Squared = 69.59676 using 59 PHA bins.
Reduced chi-squared = 1.220996 for 57 degrees of freedom
Null hypothesis probability = 0.122
Photon flux (15-150 keV) in 1.024 sec: 0.613709 ( -0.188582 0.189024 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.73334e-08 ( -1.96023e-08 2.0201e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 1.024 sec.
Parameters : value lower 90% higher 90%
Photon index: -1.29105 ( -1.70895 2.38255 )
Epeak [keV] : 73.2411 ( -21.7430 1097.51 )
Norm@50keV : 6.961339E-02 ( -6.961340E-02 0.227345 )
------------------------------------------------------------
Chi-Squared = 66.75841 using 59 PHA bins.
but latest trial 41.0093 gives Chi-Squared = 7.54025
but latest trial 0.416817 gives Chi-Squared = 5.93253
Reduced chi-squared = 1.192114 for 56 degrees of freedom
Null hypothesis probability = 0.154
Photon flux (15-150 keV) in 1.024 sec: 0.568089 ( -0.184071 0.193963 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.9902e-08 ( -1.84861e-08 2.16208e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 1.024 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.09569 ( -1.82509 3.31242 )
beta : -9.01620 ( -0.983798 8.07375 )
Epeak [keV] : 75.5849 ( -48.8989 1229.88 )
Norm@50keV : 5.679850E-02 ( -3.393131E-02 0.132519 )
------------------------------------------------------------
Chi-Squared = 66.76771 using 59 PHA bins.
Reduced chi-squared = 1.213958 for 55 degrees of freedom
Null hypothesis probability = 0.133
Photon flux (15-150 keV) in 1.024 sec: 0.568002 ( -0.18864 0.100347 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.00475e-08 ( -1.59756e-08 1.55744e-08 ) ergs/cm2
Plot creation:
Thu Dec 13 21:39:21 EST 2007