batgrbproduct Analysis for Trigger=348428
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 v2.44
Process Start Time (local time): Sat Apr 4 21:43:47 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger348428/GCN5_download_cron
======================================================================
Trigger: 00348428 Segment: 000
BAT Trigger Time: 260553395.072 [s; MET]
Trigger Stop: 260553397.12 [s; MET]
UTC: 2009-04-04T15:56:30.440760 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 239.218047211207 Dec: 35.4997092919803 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.91
Image Trigger?: NO
Rate S/N Ratio: 16.3401346383682 [ if not an image trigger ]
Image S/N Ratio: 8.91
Flight Position: [ source = BAT ]
RA: 239.218047211207 Dec: 35.4997092919803 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 239.232476169052 Dec: 35.5175611838912 [deg; J2000]
{ 15h 56m 55.8s , +35d 31' 03.2" }
+/- 0.815481079099252 [arcmin] (estimated 90% radius based on SNR)
+/- 0.214947026597793 [arcmin] (formal 1-sigma fit error)
SNR: 40.7070815498594
Angular difference between Flight and Ground position is 1.282160 arcmin
Partial Coding Fraction: 0.890625 [ including projection effects ]
Duration
T90: 83.6000000238419 +/- 13.6181431809718
Measured from: -20.1039999127388
to: 63.4960001111031 [s; relative to TRIGTIME]
T50: 39.6480000019073 +/- 1.59689698442529
Measured from: 0.752000093460083
to: 40.4000000953674 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 17.3199999928474
to: 18.3199999928474 [s; relative to TRIGTIME]
Total Fluence
Measured from: -35.1719999909401
to: 94.6400000154972 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.796158 2.300200 0.991489 0.105361
0.060299 0.059745 0.052883 0.046720 [error]
Peak 0.093162 0.079535 0.052162 0.010576
0.006399 0.006440 0.005458 0.004407 [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 8.54e-07 9.59e-07 7.70e-07 1.03e-06 2.96e-06 3.61e-06 erg/cm2
Error 5.33e-08 3.48e-08 5.28e-08 1.46e-07 1.15e-07 1.94e-07 erg/cm2
Peak flux Power-law 7.95e-01 6.50e-01 3.60e-01 2.93e-01 1.94e+00 2.10e+00 ph/cm2/s
Error 1.08e-01 5.40e-02 4.73e-02 7.74e-02 1.62e-01 1.73e-01 ph/cm2/s
Fluence Cutoff-PL 8.13e-07 9.83e-07 7.57e-07 5.94e-07 2.86e-06 3.15e-06 erg/cm2
Error 6.73e-08 4.22e-08 5.71e-08 3.62e-07 1.54e-07 3.84e-07 erg/cm2
Peak flux Cutoff-PL 7.95e-01 6.50e-01 3.60e-01 2.91e-01 1.93e+00 2.10e+00 ph/cm2/s
Error 1.08e-01 5.40e-02 4.73e-02 7.69e-02 1.62e-01 1.73e-01 ph/cm2/s
Fluence Band 8.01e-07 9.81e-07 7.54e-07 7.07e-07 2.85e-06 3.23e-06 erg/cm2
Error 6.51e-08 4.00e-08 4.57e-08 2.84e-07 1.50e-07 4.04e-07 erg/cm2
Peak flux Band 7.87e-01 6.49e-01 3.63e-01 2.99e-01 1.93e+00 2.09e+00 ph/cm2/s
Error 7.33e-02 5.35e-02 3.72e-02 6.75e-02 1.59e-01 1.73e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.318 0.084 - - 2.38e-03 1.12e-04 61.183 57
CPL 1.893 0.000 11.1 0.0 4.02e-03 0.00e+00 58.596 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.853 0.165 - - 1.38e-02 1.33e-03 52.256 57
CPL 1.853 0.166 9980.5 5000.0 1.38e-02 1.67e-03 52.262 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: 84.864000 sec.
T50 in the 50-300 keV band: 37.952000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 129.812 -35.172 94.640
T90 83.600 -20.104 63.496
T50 39.648 0.752 40.400
Peak 1.000 17.320 18.320
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
239.2325 +35.5176 0.0047 19.7 27.5 4.0929 40.7 TRIG_00348428
------------------------------------------
Foreground time interval of the image:
-35.172 26.529 (delta_t = 61.701 [sec])
Background time interval of the image:
-239.072 -35.172 (delta_t = 203.900 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -35.172 sec. to 94.640 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.31755 ( -8.357215E-02 8.541012E-02) )
Norm@50keV : 2.379297E-03 ( -1.125971E-04 1.114877E-04) )
------------------------------------------------------------
Chi-Squared = 61.18261 using 59 PHA bins.
Reduced chi-squared = 1.073379 for 57 degrees of freedom
Null hypothesis probability = 0.328
Photon flux (15-150 keV) in 129.8 sec: 0.419901 ( -0.016853 0.016962 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.96102e-06 ( -1.14717e-07 1.15249e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -35.172 sec. to 94.640 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.89266 ( )
Epeak [keV] : 11.1019 ( )
Norm@50keV : 4.023703E-03 ( )
------------------------------------------------------------
Chi-Squared = 58.59558 using 59 PHA bins.
Reduced chi-squared = 1.046350 for 56 degrees of freedom
Null hypothesis probability = 0.380
Photon flux (15-150 keV) in 129.8 sec: 0.408083 ( -0.020414 0.029722 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85581e-06 ( -1.54112e-07 1.54267e-07 ) ergs/cm2
Band function
Time interval is from -35.172 sec. to 94.640 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.56993 ( -8.43007 4.01428 )
beta : -2.48326 ( -7.23644 0.425443 )
Epeak [keV] : 20.9965 ( -10.6889 14.5088 )
Norm@50keV : 6.680054E-03 ( -4.672583E-04 1.275104E-02) )
------------------------------------------------------------
Chi-Squared = 61.03531 using 59 PHA bins.
Reduced chi-squared = 1.109733 for 55 degrees of freedom
Null hypothesis probability = 0.268
Photon flux (15-150 keV) in 129.8 sec: 0.408165 ( -0.017723 0.020327 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85493e-06 ( -1.48452e-07 1.52165e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 17.320 sec. to 18.320 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.85346 ( -0.162247 0.168145 )
Norm@50keV : 1.375057E-02 ( -1.349568E-03 1.318739E-03) )
------------------------------------------------------------
Chi-Squared = 52.25606 using 59 PHA bins.
Reduced chi-squared = 0.9167730 for 57 degrees of freedom
Null hypothesis probability = 0.653
Photon flux (15-150 keV) in 1.000 sec: 1.93551 ( -0.16194 0.16223 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.26379e-07 ( -1.2257e-08 1.2506e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 17.320 sec. to 18.320 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.85303 ( -0.163076 0.168887 )
Epeak [keV] : 9980.49 ( -9980.48 19.5098 )
Norm@50keV : 1.376219E-02 ( -1.357942E-03 1.984148E-03) )
------------------------------------------------------------
Chi-Squared = 52.26208 using 59 PHA bins.
but latest trial 1.508896E-02 gives Chi-Squared = 0.650162
Reduced chi-squared = 0.9332514 for 56 degrees of freedom
Null hypothesis probability = 0.617
Photon flux (15-150 keV) in 1.000 sec: 1.93469 ( -0.16188 0.16217 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.26421e-07 ( -1.2309e-08 1.2457e-08 ) ergs/cm2
Band function
Time interval is from 17.320 sec. to 18.320 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.48024 ( -8.51976 6.48024 )
beta : -1.85342 ( -0.168339 0.162135 )
Epeak [keV] : 11.4042 ( -11.3042 309.842 )
Norm@50keV : 3.921976E-02 ( -3.921976E-02 567.148 )
------------------------------------------------------------
Chi-Squared = 52.25610 using 59 PHA bins.
Reduced chi-squared = 0.9501109 for 55 degrees of freedom
Null hypothesis probability = 0.580
Photon flux (15-150 keV) in 1.000 sec: 1.93360 ( -0.15907 0.15989 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.26947e-07 ( -1.0756e-08 1.0437e-08 ) ergs/cm2
Plot creation:
Sat Apr 4 22:03:45 EDT 2009