Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done using the HEASARC data.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time: Mon Jan 20 03:45:12 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger306757
======================================================================
Trigger: 00306757 Segment: 000
BAT Trigger Time: 227599971.904 [s; MET]
Trigger Stop: 227599972.928 [s; MET]
UTC: 2008-03-19T06:12:49.250280 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 217.925715751808 Dec: 36.3029283586765 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 22.5
Image Trigger?: NO
Rate S/N Ratio: 206.729291586848 [ if not an image trigger ]
Image S/N Ratio: 22.5
Analysis Position: [ source = BAT ]
RA: 217.925715751808 Dec: 36.3029283586765 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 217.919211664027 Dec: 36.2998652608731 [deg; J2000]
{ 14h 31m 40.6s , +36d 17' 59.5" }
+/- 0.343203591950714 [arcmin] (estimated 90% radius based on SNR)
+/- 0.0792496452329713 [arcmin] (formal 1-sigma fit error)
SNR: 140.157316435534
Angular difference between the analysis and refined position is 0.364266 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 124.859999984503 +/- 3.09526864580048
Measured from: 5.04399999976158
to: 129.903999984264 [s; relative to TRIGTIME]
T50: 25.8040000200272 +/- 0.11063454434877
Measured from: 15.9279999732971
to: 41.7319999933243 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 16.8719999790192
to: 17.8719999790192 [s; relative to TRIGTIME]
Total Fluence
Measured from: -3.84400001168251
to: 302.047999978065 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 26.720848 41.005477 41.445959 14.857236
0.092004 0.105938 0.106957 0.088348 [error]
Peak 0.658792 1.082273 1.175623 0.432635
0.010801 0.013718 0.015119 0.012015 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 305.892 -3.844 302.048
T90 124.860 5.044 129.904
T50 25.804 15.928 41.732
Peak 1.000 16.872 17.872
====== Spectral Analysis Summary =====================================
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^{Ph_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 both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedo
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.039 -0.019 0.019 - - - 3.23e-02 -4.04e-04 4.01e-04 39.720 57
CPL -0.964 -0.022 0.020 999.060 -111.907 -999.060 3.43e-02 -2.15e-03 -1.34e-03 56.760 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -0.989 -0.034 0.034 - - - 2.18e-01 -3.92e-03 3.91e-03 37.510 57
CPL -0.984 -0.033 0.066 9999.360 -9999.360 -9999.360 2.19e-01 -3.93e-03 7.83e-03 37.750 56
=== 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 PL 6.66e-06 1.62e-05 3.16e-05 1.52e-04 8.55e-05 2.06e-04 erg/cm2
90%_error_low -1.82e-07 -2.74e-07 -3.07e-07 -3.36e-06 -8.37e-07 -3.30e-06 erg/cm2
90%_error_hi 1.85e-07 2.74e-07 3.07e-07 3.41e-06 8.35e-07 3.33e-06 erg/cm2
Peak flux PL 2.13e-03 3.25e-02 2.80e-01 3.19e+01 1.24e+00 3.13e+01 ph/cm2/s
90%_error_low N/A N/A N/A N/A N/A N/A ph/cm2/s
90%_error_hi N/A N/A N/A N/A N/A N/A ph/cm2/s
Fluence CPL 6.64e-06 1.62e-05 3.17e-05 1.51e-04 8.55e-05 2.05e-04 erg/cm2
90%_error_low -1.82e-07 -2.74e-07 -3.07e-07 N/A -8.31e-07 -3.46e-06 erg/cm2
90%_error_hi 1.84e-07 2.74e-07 3.07e-07 N/A 8.27e-07 3.30e-06 erg/cm2
Peak flux CPL 5.50e+00 7.52e+00 7.58e+00 1.38e+01 2.51e+01 3.44e+01 ph/cm2/s
90%_error_low N/A N/A N/A N/A -4.64e-01 N/A ph/cm2/s
90%_error_hi N/A N/A N/A N/A 4.65e-01 N/A ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 217.9192 36.2999 0.0014 11.7371 0.8665 25.3558505 140.157 TRIG_00306757 Foreground time interval of the image: -3.844 13.797 (delta_t = 17.641 [sec]) Background time interval of the image: -239.904 -3.844 (delta_t = 236.060 [sec])
Light Curves
Note: The mask-weighted lightcurves have units of either count/det or counts/sec/det, where a det is 0.4 x 0.4 = 0.16 sq cm.
Full-time range; 1 s binning
Other quick-look light curves:
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using 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 average DRM
Power-law model
Multiple GTIs in the spectrum tstart tstop -3.844000 62.196000 120.096000 302.048000 Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.03879 ( -0.0192978 0.0193978 ) Norm@50keV : 3.23134E-02 ( -0.000403656 0.000401333 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 39.72 using 59 PHA bins. # Reduced chi-squared = 0.6969 for 57 degrees of freedom # Null hypothesis probability = 9.602986e-01 Photon flux (15-150 keV) in 248 sec: 3.72906 ( -0.0496 0.04992 ) ph/cm2/s Energy fluence (15-150 keV) : 8.55049e-05 ( -8.36479e-07 8.34984e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum tstart tstop -3.844000 62.196000 120.096000 302.048000 Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.03184 ( -0.0224617 0.0204746 ) Epeak [keV] : 9996.11 ( -9109.97 -9997.13 ) Norm@50keV : 3.24907E-02 ( -0.000349449 0.000455681 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 41.10 using 59 PHA bins. # Reduced chi-squared = 0.7340 for 56 degrees of freedom # Null hypothesis probability = 9.321325e-01 Photon flux (15-150 keV) in 248 sec: 1.38759 ( -0.08804 0.12735 ) ph/cm2/s Energy fluence (15-150 keV) : 8.54992e-05 ( -8.30775e-07 8.26772e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 16.872 sec. to 17.872 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.98922 ( -0.0339992 0.0341892 ) Norm@50keV : 0.217868 ( -0.00392163 0.003911 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 37.51 using 59 PHA bins. # Reduced chi-squared = 0.6580 for 57 degrees of freedom # Null hypothesis probability = 9.785322e-01 Photon flux (15-150 keV) in 1 sec: 1.24323 ( ) ph/cm2/s Energy fluence (15-150 keV) : 2.36521e-06 ( -4.33822e-08 4.3475e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 16.872 sec. to 17.872 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.984461 ( -0.0328477 0.0661144 ) Epeak [keV] : 9999.36 ( -9999.36 -9999.36 ) Norm@50keV : 0.219212 ( -0.00391987 0.0078439 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 37.75 using 59 PHA bins. # Reduced chi-squared = 0.6740 for 56 degrees of freedom # Null hypothesis probability = 9.708759e-01 Photon flux (15-150 keV) in 1 sec: 25.0587 ( -0.4642 0.4648 ) ph/cm2/s Energy fluence (15-150 keV) : 4.17273e-07 ( -4.93389e-08 5.06345e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = N/A sec. Hardness ratio (energy fluence ratio) = N/A
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = N/A S(50-150 keV) = N/A
The dash-dotted line and the dashed line traces the fluences calculated from the Band function with Epeak = 15 and 150 keV, respectively. Both lines assume a canonical values of alpha = -1 and beta = -2.5.
Mask shadow pattern
IMX = 2.077416231864064E-01, IMY = -3.142059531047589E-03
Spacecraft aspect plot
Bright source in the pre-burst/pre-slew/post-slew images
Pre-burst image of 15-350 keV band
Time interval of the image: -239.904000 -3.844000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.4537 35.3407 29.1 37.5 -40.0 -0.1019 -0.4 0.2 Her X-1 236.2848 8.3961 2.6 44.1 8.3 1.3487 4.5 ------ UNKNOWN 256.3129 5.1754 2.5 58.5 -10.0 4.2496 4.5 ------ UNKNOWN 256.0041 44.3895 2.6 35.0 -55.0 1.2310 4.4 ------ UNKNOWN 113.6178 72.3511 3.1 49.3 -150.1 1.5634 3.7 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -3.844000 13.796600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3551 35.1419 0.0 37.5 -39.7 0.8176 2.7 13.0 Her X-1 185.4138 28.7862 2.6 22.6 108.0 1.0222 4.4 ------ UNKNOWN 133.7403 46.1668 2.6 49.4 173.0 2.2404 4.4 ------ UNKNOWN 217.9192 36.2999 0.1 11.7 0.9 25.3554 140.2 ------ UNKNOWN 211.2773 63.7210 3.7 19.9 -120.2 0.6723 3.2 ------ UNKNOWN 263.6960 30.6157 2.3 46.5 -40.0 2.3559 5.0 ------ UNKNOWN 265.0908 31.4628 3.0 47.1 -41.8 2.0031 3.9 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 49.396590 62.196000 120.096000 302.186000 660.096000 782.176000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.4578 35.3424 907.8 29.5 -63.0 0.0039 0.0 0.0 Her X-1 217.9468 36.2851 0.2 0.0 -37.9 14.6950 68.9 ------ UNKNOWN