batgrbproduct Analysis for Trigger=284856
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 04:14:17 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger284856/GCN5_download_cron
======================================================================
Trigger: 00284856 Segment: 000
BAT Trigger Time: 206081971.712 [s; MET]
Trigger Stop: 206081971.84 [s; MET]
UTC: 2007-07-14T04:59:29.626060 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 57.8541785265274 Dec: 28.2952010314712 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.12
Image Trigger?: NO
Rate S/N Ratio: 76.5963445602987 [ if not an image trigger ]
Image S/N Ratio: 12.12
Flight Position: [ source = BAT ]
RA: 57.8541785265274 Dec: 28.2952010314712 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 57.8607108850464 Dec: 28.2928351123897 [deg; J2000]
{ 03h 51m 26.6s , +28d 17' 34.2" }
+/- 1.36039769918898 [arcmin] (estimated 90% radius based on SNR)
+/- 0.5442409644928 [arcmin] (formal 1-sigma fit error)
SNR: 19.59598554136
RA = 3h 51m 26.6s (57.860711 deg.)
Dec = 28d 17' 34" (28.292835 deg.)
Angular difference between Flight and Ground position is 0.373170 arcmin
Partial Coding Fraction: 0.9375 [ including projection effects ]
Duration
T90: 63.9359999895096 +/- 8.40879728265565
Measured from: -0.516000002622604
to: 63.419999986887 [s; relative to TRIGTIME]
T50: 37.2680000066757 +/- 6.65182951355819
Measured from: 0.0999999940395355
to: 37.3680000007153 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.388000011444092
to: 0.611999988555908 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.796000003814697
to: 65.5999999940395 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.309527 0.413241 0.320204 0.137472
0.038979 0.039686 0.036578 0.035175 [error]
Peak 0.067979 0.122166 0.128101 0.050315
0.005753 0.006571 0.006709 0.005921 [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 8.28e-08 1.66e-07 2.58e-07 8.88e-07 7.21e-07 1.40e-06 erg/cm2
Error 1.55e-08 1.85e-08 3.56e-08 2.72e-07 8.72e-08 2.98e-07 erg/cm2
Peak flux Power-law 5.31e-01 7.82e-01 8.58e-01 1.77e+00 2.71e+00 3.94e+00 ph/cm2/s
Error 6.96e-02 6.02e-02 5.22e-02 2.51e-01 1.58e-01 2.66e-01 ph/cm2/s
Fluence Cutoff-PL 7.91e-08 1.70e-07 2.63e-07 5.86e-07 7.05e-07 1.06e-06 erg/cm2
Error 1.83e-08 2.31e-08 3.85e-08 4.83e-07 7.54e-08 6.08e-07 erg/cm2
Peak flux Cutoff-PL 5.31e-01 7.82e-01 8.58e-01 1.76e+00 2.71e+00 3.93e+00 ph/cm2/s
Error 6.95e-02 6.03e-02 5.23e-02 2.50e-01 1.58e-01 2.65e-01 ph/cm2/s
Fluence Band 8.18e-08 1.65e-07 2.58e-07 8.88e-07 7.01e-07 1.40e-06 erg/cm2
Error 1.21e-08 1.73e-08 6.52e-08 9.40e-08 1.87e-07 0.00e+00 erg/cm2
Peak flux Band 5.31e-01 7.82e-01 8.58e-01 1.76e+00 2.71e+00 3.49e+00 ph/cm2/s
Error 6.95e-02 6.03e-02 5.23e-02 2.50e-01 1.19e-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 1.359 0.191 - - 1.11e-03 1.18e-04 37.847 57
CPL 0.960 0.676 129.6 0.0 1.76e-03 0.00e+00 37.602 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.866 0.109 - - 2.36e-02 1.38e-03 72.569 57
CPL 0.860 0.110 9998.8 5000.0 2.38e-02 1.39e-03 72.593 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: 1.792000 sec.
T50 in the 50-300 keV band: 0.960000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 66.396 -0.796 65.600
T90 63.936 -0.516 63.420
T50 37.268 0.100 37.368
Peak 1.000 -0.388 0.612
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
57.8607 +28.2928 0.0098 13.2 -74.8 0.7568 19.6 TRIG_00284856
------------------------------------------
Foreground time interval of the image:
-0.796 15.389 (delta_t = 16.185 [sec])
Background time interval of the image:
-239.712 -0.796 (delta_t = 238.916 [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 -0.796 sec. to 65.600 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.35887 ( -0.190747 0.190492 )
Norm@50keV : 1.113765E-03 ( -1.180387E-04 1.174210E-04) )
------------------------------------------------------------
Chi-Squared = 37.84722 using 59 PHA bins.
Reduced chi-squared = 0.6639863 for 57 degrees of freedom
Null hypothesis probability = 0.976
Photon flux (15-150 keV) in 66.40 sec: 0.134424 ( -0.014172 0.014189 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.20818e-07 ( -8.65159e-08 8.78273e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.796 sec. to 65.600 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.960474 ( -0.774014 0.577623 )
Epeak [keV] : 129.640 ( )
Norm@50keV : 1.762971E-03 ( )
------------------------------------------------------------
Chi-Squared = 37.60200 using 59 PHA bins.
Reduced chi-squared = 0.6714643 for 56 degrees of freedom
Null hypothesis probability = 0.972
Photon flux (15-150 keV) in 66.40 sec: 0.132881 ( -0.014973 0.014654 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.05135e-07 ( -1.00936e-07 4.9873e-08 ) ergs/cm2
Band function
Time interval is from -0.796 sec. to 65.600 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.852840 ( -9.14716 4.32201 )
beta : -1.57930 ( -8.42070 0.387337 )
Epeak [keV] : 101.711 ( -101.611 9898.29 )
Norm@50keV : 2.085989E-03 ( -1.021557E-03 141.746 )
------------------------------------------------------------
Chi-Squared = 37.22278 using 59 PHA bins.
Reduced chi-squared = 0.6767778 for 55 degrees of freedom
Null hypothesis probability = 0.968
Photon flux (15-150 keV) in 66.40 sec: 0.132230 ( -0.014966 0.0149 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.01396e-07 ( -9.19301e-08 9.59878e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.388 sec. to 0.612 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.866288 ( -0.110129 0.108048 )
Norm@50keV : 2.361795E-02 ( -1.383679E-03 1.376875E-03) )
------------------------------------------------------------
Chi-Squared = 72.56937 using 59 PHA bins.
Reduced chi-squared = 1.273147 for 57 degrees of freedom
Null hypothesis probability = 8.009E-02
Photon flux (15-150 keV) in 1.000 sec: 2.71071 ( -0.1578 0.15806 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.68579e-07 ( -1.6874e-08 1.6975e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.388 sec. to 0.612 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.859587 ( -0.111014 0.108873 )
Epeak [keV] : 9998.76 ( -9998.75 1.24316 )
Norm@50keV : 2.377911E-02 ( -1.388920E-03 1.382567E-03) )
------------------------------------------------------------
Chi-Squared = 72.59334 using 59 PHA bins.
Reduced chi-squared = 1.296310 for 56 degrees of freedom
Null hypothesis probability = 6.720E-02
Photon flux (15-150 keV) in 1.000 sec: 2.70999 ( -0.15774 0.15801 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.68701e-07 ( -1.6919e-08 1.6955e-08 ) ergs/cm2
Band function
Time interval is from -0.388 sec. to 0.612 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.787080 ( -9.21292 5.78708 )
beta : -0.866293 ( -0.108011 0.110211 )
Epeak [keV] : 16.0499 ( -655.950 9343.95 )
Norm@50keV : 3.472294E-02 ( -3.851818E-03 4616.42 )
------------------------------------------------------------
Chi-Squared = 72.56936 using 59 PHA bins.
Reduced chi-squared = 1.319443 for 55 degrees of freedom
Null hypothesis probability = 5.635E-02
Photon flux (15-150 keV) in 1.000 sec: 2.71000 ( -0.15775 0.08058 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Fri Dec 14 04:29:31 EST 2007