batgrbproduct Analysis for Trigger=148646
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): Tue Jan 8 14:43:39 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger148646/SDC
======================================================================
Trigger: 00148646 Segment: 000
BAT Trigger Time: 144670081.92 [s; MET]
Trigger Stop: 144670082.944 [s; MET]
UTC: 2005-08-02T10:08:02.266620 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 219.286638875251 Dec: 27.8064461097575 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.05
Image Trigger?: NO
Rate S/N Ratio: 12.6491106406735 [ if not an image trigger ]
Image S/N Ratio: 8.05
Flight Position: [ source = BAT ]
RA: 219.286638875251 Dec: 27.8064461097575 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 219.288456828278 Dec: 27.791433893293 [deg; J2000]
{ 14h 37m 09.2s , +27d 47' 29.2" }
+/- 1.54570867554364 [arcmin] (estimated 90% radius based on SNR)
+/- 0.521900460198934 [arcmin] (formal 1-sigma fit error)
SNR: 16.3281142572272
RA = 14h 37m 9.2s (219.288457 deg.)
Dec = 27d 47' 29" (27.791434 deg.)
Angular difference between Flight and Ground position is 0.905886 arcmin
Partial Coding Fraction: 0.2246094 [ including projection effects ]
Duration
T90: 30 +/- 10.1980390271856
Measured from: -1.91999998688698
to: 28.080000013113 [s; relative to TRIGTIME]
T50: 10 +/- 2
Measured from: 0.0800000131130219
to: 10.080000013113 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.0800000131130219
to: 1.08000001311302 [s; relative to TRIGTIME]
Total Fluence
Measured from: -2.91999998688698
to: 34.080000013113 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.748950 1.107790 0.986705 0.392993
0.083170 0.088144 0.081432 0.074496 [error]
Peak 0.052521 0.107314 0.102404 0.051361
0.014650 0.015766 0.015409 0.013379 [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 3.02e-07 5.49e-07 7.67e-07 2.24e-06 2.20e-06 3.85e-06 erg/cm2
Error 4.75e-08 5.15e-08 7.80e-08 5.04e-07 1.93e-07 5.51e-07 erg/cm2
Peak flux Power-law 7.47e-01 8.46e-01 6.87e-01 9.29e-01 2.62e+00 3.21e+00 ph/cm2/s
Error 2.29e-01 1.62e-01 1.15e-01 3.20e-01 4.43e-01 4.96e-01 ph/cm2/s
Fluence Cutoff-PL 2.88e-07 5.58e-07 7.85e-07 1.76e-06 2.19e-06 3.24e-06 erg/cm2
Error 5.87e-08 4.40e-08 9.19e-08 9.22e-07 1.49e-07 9.43e-07 erg/cm2
Peak flux Cutoff-PL 6.70e-01 8.78e-01 7.33e-01 6.10e-01 2.59e+00 2.89e+00 ph/cm2/s
Error 2.76e-01 1.83e-01 1.53e-01 4.95e-01 4.46e-01 6.78e-01 ph/cm2/s
Fluence Band 2.87e-07 5.56e-07 7.82e-07 1.77e-06 2.19e-06 3.41e-06 erg/cm2
Error 5.80e-08 5.80e-08 9.29e-08 9.21e-07 1.98e-07 9.41e-07 erg/cm2
Peak flux Band 6.27e-01 9.20e-01 7.04e-01 7.94e-01 2.56e+00 3.04e+00 ph/cm2/s
Error 3.07e-01 1.93e-01 1.60e-01 5.91e-01 3.50e-01 6.25e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.519 0.148 - - 6.29e-03 5.23e-04 57.957 57
CPL 1.332 0.545 198.3 5000.0 7.69e-03 4.97e-03 57.663 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.301 0.259 - - 2.19e-02 3.42e-03 45.002 57
CPL 0.831 0.998 140.1 5000.0 3.63e-02 5.99e-02 44.423 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: 12.416000 sec.
T50 in the 50-300 keV band: 6.272000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 37.000 -2.920 34.080
T90 30.000 -1.920 28.080
T50 10.000 0.080 10.080
Peak 1.000 0.080 1.080
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
219.2885 +27.7914 0.0118 51.9 -6.4 3.3479 16.3 TRIG_00148646
------------------------------------------
Foreground time interval of the image:
-2.920 34.080 (delta_t = 37.000 [sec])
Background time interval of the image:
-67.315 -2.920 (delta_t = 64.395 [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 -2.920 sec. to 34.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.51944 ( -0.148031 0.148630 )
Norm@50keV : 6.287366E-03 ( -5.231421E-04 5.229297E-04) )
------------------------------------------------------------
Chi-Squared = 57.95729 using 59 PHA bins.
Reduced chi-squared = 1.016795 for 57 degrees of freedom
Null hypothesis probability = 0.440
Photon flux (15-150 keV) in 37.00 sec: 0.789088 ( -0.071272 0.071599 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20023e-06 ( -1.923e-07 1.92922e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.920 sec. to 34.080 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.33154 ( -0.639117 0.451088 )
Epeak [keV] : 198.286 ( -198.276 9801.71 )
Norm@50keV : 7.686847E-03 ( -2.741241E-03 7.207162E-03) )
------------------------------------------------------------
Chi-Squared = 57.66295 using 59 PHA bins.
but latest trial 1.63914 gives Chi-Squared = 2.10688
but latest trial 2.579013E-03 gives Chi-Squared = 126.161
Reduced chi-squared = 1.029696 for 56 degrees of freedom
Null hypothesis probability = 0.414
Photon flux (15-150 keV) in 37.00 sec: 0.781978 ( -0.072869 0.073807 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.18736e-06 ( -9.99333e-08 1.97846e-07 ) ergs/cm2
Band function
Time interval is from -2.920 sec. to 34.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.33778 ( -8.66222 6.32918 )
beta : -1.51944 ( -7.86063 0.759753 )
Epeak [keV] : 39.0686 ( -191.740 9808.16 )
Norm@50keV : 9.974604E-03 ( -1.930058E-03 284373. )
------------------------------------------------------------
Chi-Squared = 57.95728 using 59 PHA bins.
Reduced chi-squared = 1.053769 for 55 degrees of freedom
Null hypothesis probability = 0.367
Photon flux (15-150 keV) in 37.00 sec: 0.781991 ( -0.074451 0.074584 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.18589e-06 ( -1.99297e-07 1.9738e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.080 sec. to 1.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30115 ( -0.263510 0.255467 )
Norm@50keV : 2.194778E-02 ( -3.428847E-03 3.417216E-03) )
------------------------------------------------------------
Chi-Squared = 45.00250 using 59 PHA bins.
Reduced chi-squared = 0.7895176 for 57 degrees of freedom
Null hypothesis probability = 0.875
Photon flux (15-150 keV) in 1.000 sec: 2.61898 ( -0.4414 0.44481 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.16817e-07 ( -3.4472e-08 3.4606e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.080 sec. to 1.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.830838 ( -1.30201 0.694224 )
Epeak [keV] : 140.066 ( -140.056 9859.93 )
Norm@50keV : 3.627222E-02 ( -1.728310E-02 0.102561 )
------------------------------------------------------------
Chi-Squared = 44.42320 using 59 PHA bins.
Reduced chi-squared = 0.7932714 for 56 degrees of freedom
Null hypothesis probability = 0.868
Photon flux (15-150 keV) in 1.000 sec: 2.58745 ( -0.44377 0.44886 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.14553e-07 ( -3.5831e-08 3.56e-08 ) ergs/cm2
Band function
Time interval is from 0.080 sec. to 1.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.177547 ( -14.0268 0.973242 )
beta : -1.58965 ( -0.438026 0.310128 )
Epeak [keV] : 74.7689 ( -37.2388 520.948 )
Norm@50keV : 8.496448E-02 ( -154.123 56.4046 )
------------------------------------------------------------
Chi-Squared = 43.71640 using 59 PHA bins.
Reduced chi-squared = 0.7948436 for 55 degrees of freedom
Null hypothesis probability = 0.863
Photon flux (15-150 keV) in 1.000 sec: 2.56406 ( -0.46731 0.23343 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.14621e-07 ( -3.6004e-08 3.5378e-08 ) ergs/cm2
Plot creation:
Tue Jan 8 15:01:06 EST 2008