batgrbproduct Analysis for Trigger=279935
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 23:13:23 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger279935/GCN5_download_cron
======================================================================
Trigger: 00279935 Segment: 000
BAT Trigger Time: 201423072.832 [s; MET]
Trigger Stop: 201423073.856 [s; MET]
UTC: 2007-05-21T06:51:10.863020 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 242.669598820125 Dec: 30.2408523533459 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 11.46
Image Trigger?: NO
Rate S/N Ratio: 25.5538646783613 [ if not an image trigger ]
Image S/N Ratio: 11.46
Flight Position: [ source = BAT ]
RA: 242.669598820125 Dec: 30.2408523533459 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 242.663725526713 Dec: 30.2609524711841 [deg; J2000]
{ 16h 10m 39.3s , +30d 15' 39.4" }
+/- 1.12006764678802 [arcmin] (estimated 90% radius based on SNR)
+/- 0.399703215376444 [arcmin] (formal 1-sigma fit error)
SNR: 25.8683928315463
RA = 16h 10m 39.3s (242.663726 deg.)
Dec = 30d 15' 39" (30.260952 deg.)
Angular difference between Flight and Ground position is 1.243832 arcmin
Partial Coding Fraction: 0.4726562 [ including projection effects ]
Duration
T90: 37.772000014782 +/- 2.81938432428048
Measured from: -1.16799998283386
to: 36.6040000319481 [s; relative to TRIGTIME]
T50: 14.527999997139 +/- 0.336380725178217
Measured from: 16.4040000140667
to: 30.9320000112057 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 30.4840000271797
to: 31.4840000271797 [s; relative to TRIGTIME]
Total Fluence
Measured from: -14.5399999916553
to: 49.7320000231266 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.852620 4.501998 3.806963 0.988212
0.059961 0.063263 0.058909 0.047980 [error]
Peak 0.148922 0.303407 0.303154 0.083825
0.008590 0.010402 0.010502 0.007241 [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 9.54e-07 1.89e-06 2.90e-06 9.76e-06 8.12e-06 1.54e-05 erg/cm2
Error 4.37e-08 4.93e-08 6.48e-08 5.32e-07 1.64e-07 5.55e-07 erg/cm2
Peak flux Power-law 1.61e+00 2.07e+00 1.95e+00 3.22e+00 6.71e+00 8.85e+00 ph/cm2/s
Error 1.28e-01 1.00e-01 8.13e-02 2.88e-01 2.71e-01 3.60e-01 ph/cm2/s
Fluence Cutoff-PL 8.77e-07 1.90e-06 2.99e-06 7.11e-06 8.01e-06 1.29e-05 erg/cm2
Error 6.06e-08 5.10e-08 8.10e-08 1.31e-06 1.77e-07 1.31e-06 erg/cm2
Peak flux Cutoff-PL 1.39e+00 2.13e+00 2.09e+00 2.03e+00 6.59e+00 7.64e+00 ph/cm2/s
Error 1.62e-01 1.10e-01 1.09e-01 4.72e-01 2.76e-01 5.43e-01 ph/cm2/s
Fluence Band 8.70e-07 1.90e-06 2.98e-06 7.12e-06 8.01e-06 1.28e-05 erg/cm2
Error 6.00e-08 5.08e-08 8.10e-08 1.31e-06 1.78e-07 1.31e-06 erg/cm2
Peak flux Band 1.39e+00 2.13e+00 2.09e+00 2.03e+00 6.59e+00 7.64e+00 ph/cm2/s
Error 1.62e-01 1.10e-01 1.09e-01 4.72e-01 2.77e-01 5.43e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.380 0.039 - - 1.30e-02 2.64e-04 58.329 57
CPL 1.101 0.169 193.0 116.9 1.70e-02 2.73e-03 49.929 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.090 0.067 - - 5.79e-02 2.25e-03 65.982 57
CPL 0.553 0.286 158.4 68.9 9.97e-02 2.86e-02 54.350 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: 33.216000 sec.
T50 in the 50-300 keV band: 9.280000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 64.272 -14.540 49.732
T90 37.772 -1.168 36.604
T50 14.528 16.404 30.932
Peak 1.000 30.484 31.484
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
242.6637 +30.2610 0.0074 26.4 91.6 2.3288 25.9 TRIG_00279935
------------------------------------------
Foreground time interval of the image:
-14.540 12.669 (delta_t = 27.209 [sec])
Background time interval of the image:
-98.731 -14.540 (delta_t = 84.191 [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 -14.540 sec. to 49.732 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37978 ( -3.937888E-02 3.928876E-02) )
Norm@50keV : 1.302581E-02 ( -2.639014E-04 2.636630E-04) )
------------------------------------------------------------
Chi-Squared = 58.32870 using 59 PHA bins.
Reduced chi-squared = 1.023310 for 57 degrees of freedom
Null hypothesis probability = 0.426
Photon flux (15-150 keV) in 64.27 sec: 1.57918 ( -0.0372 0.03736 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.12321e-06 ( -1.63953e-07 1.64338e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -14.540 sec. to 49.732 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.10063 ( -0.172403 0.165751 )
Epeak [keV] : 192.976 ( -50.8989 182.954 )
Norm@50keV : 1.704513E-02 ( -2.463383E-03 2.994599E-03) )
------------------------------------------------------------
Chi-Squared = 49.92891 using 59 PHA bins.
Reduced chi-squared = 0.8915876 for 56 degrees of freedom
Null hypothesis probability = 0.703
Photon flux (15-150 keV) in 64.27 sec: 1.54247 ( -0.04226 0.04227 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.01363e-06 ( -1.78349e-07 1.75457e-07 ) ergs/cm2
Band function
Time interval is from -14.540 sec. to 49.732 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.10504 ( -0.162173 0.177449 )
beta : -1.93280 ( -6.04089 2.52331 )
Epeak [keV] : 195.198 ( -110.445 181.875 )
Norm@50keV : 1.693896E-02 ( -2.456327E-03 3.004583E-03) )
------------------------------------------------------------
Chi-Squared = 49.95476 using 59 PHA bins.
Reduced chi-squared = 0.9082683 for 55 degrees of freedom
Null hypothesis probability = 0.667
Photon flux (15-150 keV) in 64.27 sec: 1.54242 ( -0.04219 0.04251 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.00798e-06 ( -1.78928e-07 1.77449e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 30.484 sec. to 31.484 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.09025 ( -6.681812E-02 6.644058E-02) )
Norm@50keV : 5.793282E-02 ( -2.253477E-03 2.251755E-03) )
------------------------------------------------------------
Chi-Squared = 65.98244 using 59 PHA bins.
Reduced chi-squared = 1.157587 for 57 degrees of freedom
Null hypothesis probability = 0.194
Photon flux (15-150 keV) in 1.000 sec: 6.71361 ( -0.27056 0.27101 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.07602e-07 ( -2.5048e-08 2.5083e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.484 sec. to 31.484 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.553246 ( -0.295844 0.276285 )
Epeak [keV] : 158.396 ( -36.3008 101.576 )
Norm@50keV : 9.968252E-02 ( -2.377375E-02 3.343128E-02) )
------------------------------------------------------------
Chi-Squared = 54.34991 using 59 PHA bins.
Reduced chi-squared = 0.9705340 for 56 degrees of freedom
Null hypothesis probability = 0.538
Photon flux (15-150 keV) in 1.000 sec: 6.59334 ( -0.2761 0.27682 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.99355e-07 ( -2.6235e-08 2.5997e-08 ) ergs/cm2
Band function
Time interval is from 30.484 sec. to 31.484 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.553101 ( -0.208884 0.296330 )
beta : -4.91098 ( -5.08902 3.74048 )
Epeak [keV] : 158.417 ( -22.3414 101.556 )
Norm@50keV : 9.967484E-02 ( -2.621017E-02 3.345262E-02) )
------------------------------------------------------------
Chi-Squared = 54.34994 using 59 PHA bins.
Reduced chi-squared = 0.9881808 for 55 degrees of freedom
Null hypothesis probability = 0.499
Photon flux (15-150 keV) in 1.000 sec: 6.59332 ( -0.27641 0.27684 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.98953e-07 ( -2.6186e-08 2.6014e-08 ) ergs/cm2
Plot creation:
Thu Dec 13 23:31:41 EST 2007