batgrbproduct Analysis for Trigger=272773
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 16:00:00 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger272773/GCN5_download_cron
======================================================================
Trigger: 00272773 Segment: 000
BAT Trigger Time: 196746835.008 [s; MET]
Trigger Stop: 196746836.032 [s; MET]
UTC: 2007-03-28T03:53:53.155520 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 65.1167749451009 Dec: -34.0690105976273 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 16.55
Image Trigger?: NO
Rate S/N Ratio: 75.5645419492502 [ if not an image trigger ]
Image S/N Ratio: 16.55
Flight Position: [ source = BAT ]
RA: 65.1167749451009 Dec: -34.0690105976273 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 65.1153984960438 Dec: -34.0765402402704 [deg; J2000]
{ 04h 20m 27.7s , -34d 04' 35.5" }
+/- 0.652363739928469 [arcmin] (estimated 90% radius based on SNR)
+/- 0.232621609488978 [arcmin] (formal 1-sigma fit error)
SNR: 55.9928961950888
RA = 4h 20m 27.7s (65.115398 deg.)
Dec = -34d 4' 36" (-34.076540 deg.)
Angular difference between Flight and Ground position is 0.456928 arcmin
Partial Coding Fraction: 0.609375 [ including projection effects ]
Duration
T90: 75.3560000061989 +/- 9.12248740228675
Measured from: -3.81999999284744
to: 71.5360000133514 [s; relative to TRIGTIME]
T50: 18.0439999997616 +/- 0.806781254679827
Measured from: 3.83200001716614
to: 21.8760000169277 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.784000009298325
to: 1.78400000929832 [s; relative to TRIGTIME]
Total Fluence
Measured from: -17.9679999947548
to: 130.716000020504 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.786642 4.483317 4.319090 1.418662
0.066423 0.069305 0.063197 0.051912 [error]
Peak 0.105493 0.167104 0.189139 0.072195
0.007885 0.009088 0.009090 0.007476 [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 0.00e+00 0.00e+00 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 Power-law 1.02e+00 1.30e+00 1.22e+00 2.00e+00 4.22e+00 5.54e+00 ph/cm2/s
Error 1.21e-01 9.18e-02 7.12e-02 2.62e-01 2.42e-01 3.13e-01 ph/cm2/s
Fluence Cutoff-PL 8.89e-07 1.99e-06 3.36e-06 1.06e-05 9.05e-06 1.65e-05 erg/cm2
Error 4.77e-08 5.58e-08 9.15e-08 2.21e-06 1.85e-07 2.10e-06 erg/cm2
Peak flux Cutoff-PL 1.02e+00 1.30e+00 1.22e+00 1.99e+00 4.21e+00 5.53e+00 ph/cm2/s
Error 1.20e-01 9.19e-02 7.13e-02 2.60e-01 2.42e-01 3.12e-01 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 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 5.55e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.264 0.000 - - 6.13e-03 0.00e+00 37.388 57
CPL 1.098 0.166 343.6 4895.1 7.14e-03 1.04e-03 34.907 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.100 0.100 - - 3.63e-02 1.99e-03 55.634 57
CPL 1.096 0.100 9997.3 5000.0 3.65e-02 2.00e-03 55.644 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: 53.376000 sec.
T50 in the 50-300 keV band: 16.704000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 148.684 -17.968 130.716
T90 75.356 -3.820 71.536
T50 18.044 3.832 21.876
Peak 1.000 0.784 1.784
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
65.1154 -34.0765 0.0034 39.6 -167.9 5.8677 56.0 TRIG_00272773
------------------------------------------
Foreground time interval of the image:
-17.968 11.193 (delta_t = 29.161 [sec])
Background time interval of the image:
-74.807 -17.968 (delta_t = 56.839 [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 -17.968 sec. to 130.716 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.26394 ( )
Norm@50keV : 6.134936E-03 ( )
------------------------------------------------------------
Chi-Squared = 37.38800 using 59 PHA bins.
Reduced chi-squared = 0.6559297 for 57 degrees of freedom
Null hypothesis probability = 0.979
Photon flux (15-150 keV) in 148.7 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -17.968 sec. to 130.716 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.09782 ( -0.154578 0.176423 )
Epeak [keV] : 343.555 ( -133.703 9656.44 )
Norm@50keV : 7.138491E-03 ( -1.024342E-03 1.050865E-03) )
------------------------------------------------------------
Chi-Squared = 34.90680 using 59 PHA bins.
but latest trial 1.27388 gives Chi-Squared = 2.87121
Reduced chi-squared = 0.6233358 for 56 degrees of freedom
Null hypothesis probability = 0.988
Photon flux (15-150 keV) in 148.7 sec: 0.718079 ( -0.020502 0.01988 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.05147e-06 ( -1.84671e-07 1.86113e-07 ) ergs/cm2
Band function
Time interval is from -17.968 sec. to 130.716 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.972742 ( -9.02726 1.51387 )
beta : -1.30155 ( -8.51946 0.228688 )
Epeak [keV] : 162.114 ( -362.492 805.751 )
Norm@50keV : 8.579951E-03 ( -9.525241E-04 3.636822E-03) )
------------------------------------------------------------
Chi-Squared = 36.26555 using 59 PHA bins.
Reduced chi-squared = 0.6593736 for 55 degrees of freedom
Null hypothesis probability = 0.976
Photon flux (15-150 keV) in 148.7 sec: ( ) 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 0.784 sec. to 1.784 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.09960 ( -0.100296 9.898639E-02) )
Norm@50keV : 3.633977E-02 ( -1.994874E-03 1.986198E-03) )
------------------------------------------------------------
Chi-Squared = 55.63404 using 59 PHA bins.
Reduced chi-squared = 0.9760359 for 57 degrees of freedom
Null hypothesis probability = 0.526
Photon flux (15-150 keV) in 1.000 sec: 4.21502 ( -0.24163 0.24234 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.80031e-07 ( -2.189e-08 2.1899e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.784 sec. to 1.784 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.09601 ( -0.102833 9.803712E-02) )
Epeak [keV] : 9997.26 ( -9997.25 2.74023 )
Norm@50keV : 3.653981E-02 ( -1.999628E-03 1.991902E-03) )
------------------------------------------------------------
Chi-Squared = 55.64445 using 59 PHA bins.
Reduced chi-squared = 0.9936510 for 56 degrees of freedom
Null hypothesis probability = 0.488
Photon flux (15-150 keV) in 1.000 sec: 4.21377 ( -0.24155 0.24225 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.80083e-07 ( -2.1843e-08 2.1979e-08 ) ergs/cm2
Band function
Time interval is from 0.784 sec. to 1.784 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.747545 ( -10.7325 2.39688 )
beta : -1.10228 ( -0.105609 0.100816 )
Epeak [keV] : 78.8086 ( -30.8813 2805.25 )
Norm@50keV : 6.905216E-02 ( -1.14334 4478.99 )
------------------------------------------------------------
Chi-Squared = 55.55726 using 59 PHA bins.
Reduced chi-squared = 1.010132 for 55 degrees of freedom
Null hypothesis probability = 0.454
Photon flux (15-150 keV) in 1.000 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Thu Dec 13 16:22:40 EST 2007