batgrbproduct Analysis for Trigger=345777
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 v2.42
Process Start Time (local time): Mon Mar 9 05:26:10 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger345777/GCN5_download_cron
======================================================================
Trigger: 00345777 Segment: 000
BAT Trigger Time: 258228088 [s; MET]
Trigger Stop: 258228152 [s; MET]
UTC: 2009-03-08T18:01:23.441660 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 183.526014699304 Dec: -48.8329591097236 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.92
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.92
Flight Position: [ source = BAT ]
RA: 183.526014699304 Dec: -48.8329591097236 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 183.511589205793 Dec: -48.7325213477864 [deg; J2000]
{ 12h 14m 02.8s , -48d 43' 57.1" }
+/- 2.5286674745595 [arcmin] (estimated 90% radius based on SNR)
+/- 1.55598870659973 [arcmin] (formal 1-sigma fit error)
SNR: 8.08274311957051
Angular difference between Flight and Ground position is 6.053192 arcmin
Partial Coding Fraction: 0.890625 [ including projection effects ]
Duration
T90: 24 +/- 3.60555127546399
Measured from: 17.000000089407
to: 41.000000089407 [s; relative to TRIGTIME]
T50: 12 +/- 7.28010988928052
Measured from: 25.000000089407
to: 37.000000089407 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 35
to: 36 [s; relative to TRIGTIME]
Total Fluence
Measured from: 16
to: 43 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.236488 0.184544 0.030878 -0.000532
0.029020 0.027470 0.023478 0.020928 [error]
Peak 0.004221 0.025696 0.004058 0.001142
0.005359 0.005338 0.004573 0.004080 [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 6.51e-08 6.68e-08 4.84e-08 5.60e-08 2.02e-07 2.36e-07 erg/cm2
Error 1.30e-08 1.29e-08 1.83e-08 3.98e-08 4.35e-08 6.71e-08 erg/cm2
Peak flux Power-law 1.19e-01 1.02e-01 5.95e-02 5.18e-02 3.03e-01 3.33e-01 ph/cm2/s
Error 6.30e-02 4.02e-02 3.32e-02 5.57e-02 1.20e-01 1.35e-01 ph/cm2/s
Fluence Cutoff-PL 6.08e-08 7.97e-08 3.57e-08 3.85e-09 1.80e-07 1.80e-07 erg/cm2
Error 1.45e-08 1.80e-08 2.25e-08 2.13e-08 4.04e-08 4.58e-08 erg/cm2
Peak flux Cutoff-PL 8.76e-02 1.59e-01 4.79e-02 9.29e-04 2.95e-01 2.94e-01 ph/cm2/s
Error 4.60e-02 5.54e-02 3.56e-02 6.44e-03 1.02e-01 1.02e-01 ph/cm2/s
Fluence Band 6.01e-08 7.95e-08 3.59e-08 3.95e-09 1.80e-07 1.81e-07 erg/cm2
Error 1.28e-08 1.17e-08 1.01e-08 2.68e-08 2.88e-08 5.08e-08 erg/cm2
Peak flux Band 7.53e-02 1.67e-01 4.22e-02 5.43e-04 2.84e-01 3.05e-01 ph/cm2/s
Error 6.84e-02 5.78e-02 3.06e-02 1.52e-02 9.72e-02 1.09e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.466 0.360 - - 7.55e-04 2.12e-04 66.446 57
CPL 0.695 1.840 26.1 17.7 1.01e-02 1.81e-01 62.948 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.778 0.641 - - 2.22e-03 1.00e-03 58.634 57
CPL -2.495 0.000 42.0 10.2 7.33e-01 2.08e+00 52.972 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 27.000 16.000 43.000
T90 24.000 17.000 41.000
T50 12.000 25.000 37.000
Peak 1.000 35.000 36.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
183.5116 -48.7325 0.0240 15.1 133.4 0.4164 8.1 TRIG_00345777
------------------------------------------
Foreground time interval of the image:
16.000 43.000 (delta_t = 27.000 [sec])
Background time interval of the image:
-239.000 -56.720 (delta_t = 182.280 [sec])
-55.000 16.000 (delta_t = 71.000 [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.
- 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 16.000 sec. to 43.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.46626 ( -0.333521 0.386432 )
Norm@50keV : 7.554423E-04 ( -2.121167E-04 2.116517E-04) )
------------------------------------------------------------
Chi-Squared = 66.44621 using 59 PHA bins.
Reduced chi-squared = 1.165723 for 57 degrees of freedom
Null hypothesis probability = 0.184
Photon flux (15-150 keV) in 27.00 sec: 0.145353 ( -0.024211 0.024225 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.02054e-07 ( -4.21794e-08 4.48308e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 16.000 sec. to 43.000 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.694797 ( -2.36431 1.31509 )
Epeak [keV] : 26.1311 ( -26.1211 9.23982 )
Norm@50keV : 1.008071E-02 ( -1.008071E-02 0.352657 )
------------------------------------------------------------
Chi-Squared = 62.94847 using 59 PHA bins.
but latest trial 2.00988 gives Chi-Squared = 8.73999
Reduced chi-squared = 1.124080 for 56 degrees of freedom
Null hypothesis probability = 0.244
Photon flux (15-150 keV) in 27.00 sec: 0.140554 ( -0.01212 0.024119 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.79753e-07 ( -3.67003e-08 4.40286e-08 ) ergs/cm2
Band function
Time interval is from 16.000 sec. to 43.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.37123 ( -1.24248 4.30027 )
beta : -8.81660 ( -1.18340 6.36530 )
Epeak [keV] : 20.7723 ( -14.0055 15.2509 )
Norm@50keV : 3.728569E-03 ( -5.549515E-03 0.214525 )
------------------------------------------------------------
Chi-Squared = 63.34105 using 59 PHA bins.
Reduced chi-squared = 1.151655 for 55 degrees of freedom
Null hypothesis probability = 0.206
Photon flux (15-150 keV) in 27.00 sec: 0.140241 ( -0.023119 0.023588 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.79613e-07 ( -3.49753e-08 2.25871e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 35.000 sec. to 36.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.77753 ( -0.603715 0.678137 )
Norm@50keV : 2.217807E-03 ( -1.010234E-03 9.941410E-04) )
------------------------------------------------------------
Chi-Squared = 58.63353 using 59 PHA bins.
Reduced chi-squared = 1.028658 for 57 degrees of freedom
Null hypothesis probability = 0.415
Photon flux (15-150 keV) in 1.000 sec: 0.303083 ( -0.11968 0.119709 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.04435e-08 ( -9.0726e-09 9.8416e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 35.000 sec. to 36.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.49513 ( )
Epeak [keV] : 42.0269 ( -8.72276 11.5938 )
Norm@50keV : 0.732803 ( -1.39520 2.76200 )
------------------------------------------------------------
Chi-Squared = 52.97226 using 59 PHA bins.
Reduced chi-squared = 0.9459332 for 56 degrees of freedom
Null hypothesis probability = 0.590
Photon flux (15-150 keV) in 1.000 sec: 0.294557 ( -0.1019 0.102682 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.69071e-08 ( -6.0614e-09 6.5337e-09 ) ergs/cm2
Band function
Time interval is from 35.000 sec. to 36.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.73409 ( -5.04770 5.443811E-02) )
beta : -5.31729 ( -1.330185E-02 7.62644 )
Epeak [keV] : 43.1962 ( -41.6514 38.7092 )
Norm@50keV : 0.252878 ( -15.4254 53.4207 )
------------------------------------------------------------
Chi-Squared = 53.43414 using 59 PHA bins.
Reduced chi-squared = 0.9715299 for 55 degrees of freedom
Null hypothesis probability = 0.535
Photon flux (15-150 keV) in 1.000 sec: 0.283824 ( -0.097964 0.096454 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.81801e-08 ( -6.6491e-09 8.8424e-09 ) ergs/cm2
Plot creation:
Mon Mar 9 06:00:14 EDT 2009