batgrbproduct Analysis for Trigger=255685
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 11:28:37 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger255685/GCN5_download_cron
======================================================================
Trigger: 00255685 Segment: 000
BAT Trigger Time: 190241386.848 [s; MET]
Trigger Stop: 190241387.232 [s; MET]
UTC: 2007-01-11T20:49:45.155160 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 32 ms to TRIGTIME + 320 ms
BAT
RA: 99.939569141939 Dec: -56.09959793717 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.5
Image Trigger?: NO
Rate S/N Ratio: 8.30662386291807 [ if not an image trigger ]
Image S/N Ratio: 6.5
Flight Position: [ source = BAT ]
RA: 99.939569141939 Dec: -56.09959793717 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 99.9308169420152 Dec: -55.9624551248171 [deg; J2000]
{ 06h 39m 43.4s , -55d 57' 44.8" }
+/- 9.95980031159652 [arcmin] (estimated 90% radius based on SNR)
+/- 9.12202877202957 [arcmin] (formal 1-sigma fit error)
SNR: 1.14037069866748
RA = 6h 39m 43.4s (99.930817 deg.)
Dec = -55d 57' 45" (-55.962455 deg.)
Angular difference between Flight and Ground position is 8.233798 arcmin
Partial Coding Fraction: 0.6796875 [ including projection effects ]
Duration
T90: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
T50: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 0.38400000333786 second)
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.005038 -0.001731 -0.001653 0.006483
0.003801 0.003542 0.003167 0.002947 [error]
Peak 0.005038 -0.001731 -0.001653 0.006483
0.003801 0.003542 0.003167 0.002947 [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 1.60e-09 7.96e-11 1.29e-12 2.14e-14 1.67e-09 1.66e-09 erg/cm2
Error 1.68e-09 4.30e-10 8.51e-11 2.15e-11 2.03e-09 2.03e-09 erg/cm2
Peak flux Power-law 1.51e-01 4.45e-03 3.64e-05 3.00e-07 1.55e-01 1.54e-01 ph/cm2/s
Error 1.54e-01 2.22e-02 2.17e-03 2.52e-04 1.70e-01 1.70e-01 ph/cm2/s
Fluence Cutoff-PL 9.54e-13 7.92e-11 1.29e-12 2.12e-14 1.67e-09 0.00e+00 erg/cm2
Error 4.30e-10 8.49e-11 2.13e-11 2.03e-09 0.00e+00 0.00e+00 erg/cm2
Peak flux Cutoff-PL 1.50e-01 4.43e-03 3.60e-05 2.95e-07 1.55e-01 0.00e+00 ph/cm2/s
Error 1.54e-01 2.21e-02 2.16e-03 2.50e-04 1.69e-01 0.00e+00 ph/cm2/s
Fluence Band 5.40e-15 2.90e-11 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 1.51e-01 4.51e-03 3.75e-05 3.09e-07 1.55e-01 0.00e+00 ph/cm2/s
Error 1.54e-01 2.21e-02 2.16e-03 2.50e-04 1.69e-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 8.163 2.906 - - 3.84e-06 1.60e-04 59.660 57
CPL 1.000 6.500 50.0 5000.0 0.00e+00 0.00e+00 65.270 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 8.163 2.906 - - 3.84e-06 1.60e-04 59.660 57
CPL 1.000 6.500 50.0 5000.0 0.00e+00 0.00e+00 65.270 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.384 0.000 0.384
T90 0.384 0.000 0.384
T50 0.384 0.000 0.384
Peak 0.384 0.000 0.384
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
99.9308 -55.9625 0.1682 33.5 5.4 0.0080 1.1 TRIG_00255685
------------------------------------------
Foreground time interval of the image:
-0.032 0.352 (delta_t = 0.384 [sec])
Background time interval of the image:
-239.880 -2.880 (delta_t = 237.000 [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 -0.032 sec. to 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 8.16279 ( -3.97505 1.83721 )
Norm@50keV : 3.840923E-06 ( -3.840923E-06 3.153704E-04) )
------------------------------------------------------------
Chi-Squared = 59.66004 using 59 PHA bins.
Reduced chi-squared = 1.046667 for 57 degrees of freedom
Null hypothesis probability = 0.379
Photon flux (15-150 keV) in 0.3840 sec: 0.154843 ( -0.154843 0.184363 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.67066e-09 ( -1.67066e-09 2.38649e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( -4.00000 9.00000 )
Epeak [keV] : 50.0000 ( -49.9900 9950.00 )
Norm@50keV : 0.00000 ( )
------------------------------------------------------------
Chi-Squared = 65.26984 using 59 PHA bins.
Reduced chi-squared = 1.165533 for 56 degrees of freedom
Null hypothesis probability = 0.186
Photon flux (15-150 keV) in 0.3840 sec: 0.154536 ( -0.154536 0.184327 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66812e-09 ( -1.66812e-09 2.38658e-09 ) ergs/cm2
Band function
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.983950 ( -9.01605 5.98395 )
beta : -2.50000 ( -7.50000 12.5000 )
Epeak [keV] : 80.0000 ( -79.9000 9920.00 )
Norm@50keV : 0.00000 ( -1.13504 3776.26 )
------------------------------------------------------------
Chi-Squared = 65.26984 using 59 PHA bins.
Reduced chi-squared = 1.186724 for 55 degrees of freedom
Null hypothesis probability = 0.162
Photon flux (15-150 keV) in 0.3840 sec: 0.154692 ( -0.154692 0.184168 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 8.16279 ( -3.97505 1.83721 )
Norm@50keV : 3.840923E-06 ( -3.840923E-06 3.153704E-04) )
------------------------------------------------------------
Chi-Squared = 59.66004 using 59 PHA bins.
Reduced chi-squared = 1.046667 for 57 degrees of freedom
Null hypothesis probability = 0.379
Photon flux (15-150 keV) in 0.3840 sec: 0.154843 ( -0.154843 0.184363 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.67066e-09 ( -1.67066e-09 2.38649e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( -4.00000 9.00000 )
Epeak [keV] : 50.0000 ( -49.9900 9950.00 )
Norm@50keV : 0.00000 ( )
------------------------------------------------------------
Chi-Squared = 65.26984 using 59 PHA bins.
Reduced chi-squared = 1.165533 for 56 degrees of freedom
Null hypothesis probability = 0.186
Photon flux (15-150 keV) in 0.3840 sec: 0.154536 ( -0.154536 0.184327 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66812e-09 ( -1.66812e-09 2.38658e-09 ) ergs/cm2
Band function
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.983950 ( -9.01605 5.98395 )
beta : -2.50000 ( -7.50000 12.5000 )
Epeak [keV] : 80.0000 ( -79.9000 9920.00 )
Norm@50keV : 0.00000 ( -1.13504 3776.26 )
------------------------------------------------------------
Chi-Squared = 65.26984 using 59 PHA bins.
Reduced chi-squared = 1.186724 for 55 degrees of freedom
Null hypothesis probability = 0.162
Photon flux (15-150 keV) in 0.3840 sec: 0.154692 ( -0.154692 0.184168 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Thu Dec 13 11:48:29 EST 2007