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 v2.48
Process Start Time: Sun May 12 20:30:28 EDT 2024
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1227767/GCN5_download_cron
======================================================================
Trigger: 01227767 Segment: 000
BAT Trigger Time: 737143646.656 [s; MET]
Trigger Stop: 737143648.704 [s; MET]
UTC: 2024-05-11T18:06:53.226840 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 336.664509948977 Dec: 8.51351293746527 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.52
Image Trigger?: NO
Rate S/N Ratio: 14.8996644257513 [ if not an image trigger ]
Image S/N Ratio: 8.52
Analysis Position: [ source = BAT ]
RA: 336.664509948977 Dec: 8.51351293746527 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 336.668521076857 Dec: 8.51416525750696 [deg; J2000]
{ 22h 26m 40.4s , +08d 30' 51.0" }
+/- 0.689232651612834 [arcmin] (estimated 90% radius based on SNR)
+/- 0.235260275407324 [arcmin] (formal 1-sigma fit error)
SNR: 51.7635815640006
Angular difference between the analysis and refined position is 0.241212 arcmin
Partial Coding Fraction: 0.8515625 [ including projection effects ]
Duration
T90: 148.536000013351 +/- 17.0657857031545
Measured from: -44.8279999494553
to: 103.708000063896 [s; relative to TRIGTIME]
T50: 59.9880000352859 +/- 2.39597334507173
Measured from: -15.095999956131
to: 44.892000079155 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 35.1480000019073
to: 36.1480000019073 [s; relative to TRIGTIME]
Total Fluence
Measured from: -92.0119999647141
to: 203.703999996185 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.891166 6.502661 4.679380 1.151685
0.099978 0.104191 0.089568 0.072790 [error]
Peak 0.074694 0.123857 0.094247 0.022257
0.007559 0.008561 0.007527 0.005405 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 295.716 -92.012 203.704
T90 148.536 -44.828 103.708
T50 59.988 -15.096 44.892
Peak 1.000 35.148 36.148
====== 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 -1.582 -0.042 0.042 - - - 4.39e-03 -9.56e-05 9.56e-05 42.730 57
CPL -1.403 -0.168 0.174 185.591 -64.702 2380.679 5.29e-03 -8.12e-04 1.02e-03 39.450 56
=== 1-s peak 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 -1.437 -0.131 0.130 - - - 2.09e-02 -1.64e-03 1.64e-03 60.620 57
CPL -1.220 -0.288 0.555 182.912 -182.912 -182.912 2.69e-02 -7.41e-03 2.37e-02 60.090 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 1.55e-06 2.71e-06 3.63e-06 9.93e-06 1.06e-05 1.78e-05 erg/cm2
90%_error_low -6.97e-08 -7.04e-08 -9.62e-08 -6.00e-07 -2.36e-07 -6.45e-07 erg/cm2
90%_error_hi 7.11e-08 7.03e-08 9.60e-08 6.26e-07 2.36e-07 6.65e-07 erg/cm2
Peak flux PL 8.11e-01 8.47e-01 6.26e-01 7.46e-01 2.57e+00 3.03e+00 ph/cm2/s
90%_error_low -1.07e-01 -7.13e-02 -6.02e-02 -1.37e-01 -2.03e-01 -2.38e-01 ph/cm2/s
90%_error_hi 1.11e-01 7.08e-02 5.97e-02 1.54e-01 2.03e-01 2.39e-01 ph/cm2/s
Fluence CPL 1.48e-06 2.74e-06 3.68e-06 7.88e-06 1.04e-05 1.58e-05 erg/cm2
90%_error_low -9.26e-08 -7.44e-08 -1.08e-07 -1.50e-06 -2.65e-07 -1.52e-06 erg/cm2
90%_error_hi 9.46e-08 7.47e-08 1.09e-07 1.91e-06 2.64e-07 1.92e-06 erg/cm2
Peak flux CPL 7.81e-01 8.66e-01 6.40e-01 5.78e-01 2.55e+00 2.86e+00 ph/cm2/s
90%_error_low -1.27e-01 -8.30e-02 -6.77e-02 -2.53e-01 -2.07e-01 -3.34e-01 ph/cm2/s
90%_error_hi 1.26e-01 8.59e-02 6.92e-02 2.13e-01 2.07e-01 3.13e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 336.6685 8.5142 0.0037 28.3846 -173.5370 9.1260616 51.764 TRIG_01227767 Foreground time interval of the image: -92.012 -13.852 (delta_t = 78.160 [sec]) -12.656 -12.426 (delta_t = 0.230 [sec]) -11.656 -11.546 (delta_t = 0.110 [sec]) -10.656 8.174 (delta_t = 18.830 [sec]) 21.344 24.845 (delta_t = 3.501 [sec]) Background time interval of the image: -239.656 -92.012 (delta_t = 147.644 [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 -92.012000 -13.851700 -12.656000 -12.426000 -11.656000 -11.546000 -10.656000 8.174000 21.344000 155.994000 157.344000 157.454000 158.344000 158.584000 159.344000 159.924000 180.344000 203.704000 Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.58165 ( -0.0421925 0.042186 ) Norm@50keV : 4.39358E-03 ( -9.55954e-05 9.55953e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 42.73 using 59 bins. Reduced chi-squared = 0.749649 # Null hypothesis probability of 9.20e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 256.3 sec: 0.561451 ( -0.014184 0.014242 ) ph/cm2/s Energy fluence (15-150 keV) : 1.05569e-05 ( -2.36259e-07 2.36214e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum tstart tstop -92.012000 -13.851700 -12.656000 -12.426000 -11.656000 -11.546000 -10.656000 8.174000 21.344000 155.994000 157.344000 157.454000 158.344000 158.584000 159.344000 159.924000 180.344000 203.704000 Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.40316 ( -0.167626 0.17447 ) Epeak [keV] : 185.591 ( -64.74 2380.65 ) Norm@50keV : 5.28886E-03 ( -0.000811855 0.00102247 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 39.45 using 59 bins. Reduced chi-squared = 0.704464 # Null hypothesis probability of 9.54e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 256.3 sec: 0.552947 ( -0.01607 0.01617 ) ph/cm2/s Energy fluence (15-150 keV) : 1.04287e-05 ( -2.65278e-07 2.64309e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 35.148 sec. to 36.148 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.43659 ( -0.13097 0.130348 ) Norm@50keV : 2.09284E-02 ( -0.00163986 0.00163574 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 60.62 using 59 bins. Reduced chi-squared = 1.06351 # Null hypothesis probability of 3.47e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 2.57072 ( -0.20277 0.20296 ) ph/cm2/s Energy fluence (15-150 keV) : 2.00798e-07 ( -1.72372e-08 1.73444e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 35.148 sec. to 36.148 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.22001 ( -0.287691 0.554746 ) Epeak [keV] : 182.912 ( -182.933 -182.933 ) Norm@50keV : 2.69440E-02 ( -0.00741363 0.0237355 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 60.09 using 59 bins. Reduced chi-squared = 1.07304 # Null hypothesis probability of 3.30e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 2.55294 ( -0.20712 0.20704 ) ph/cm2/s Energy fluence (15-150 keV) : 1.98089e-07 ( -1.86363e-08 1.8437e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 148.536 sec. Hardness ratio (energy fluence ratio) = 1.33644161788
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 4.266348e-06 S(50-150 keV) = 6.290545e-06
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 = -5.369171108225050E-01, IMY = 6.082231970598598E-02
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: -239.656000 -92.012000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 309.7853 -32.6420 4.3 32.1 77.4 1.0743 2.7 ------ UNKNOWN 331.7526 29.0190 2.5 49.4 -173.8 2.2340 4.6 ------ UNKNOWN 349.1950 26.9756 2.1 46.7 -153.2 2.2087 5.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -92.012000 -13.851700 -12.656000 -12.426000 -11.656000 -11.546000 -10.656000 8.174000 21.344000 24.844590 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 336.6685 8.5142 0.2 28.4 -173.5 9.1261 51.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 91.044580 155.994000 157.344000 157.454000 158.344000 158.584000 159.344000 159.924000 180.344000 232.454000 233.344000 327.594000 328.344000 647.330200 660.344000 712.104000 720.344000 758.434000 765.344000 773.984000 780.344000 799.153200 800.344000 809.964000 817.344000 822.834000 829.344000 846.004000 849.344000 863.764000 866.344000 866.814000 868.344000 882.554000 884.344000 962.416100 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 299.5934 35.1950 1.2 43.1 150.4 27.1416 9.5 0.4 Cyg X-1 308.0864 40.9302 3.4 41.1 163.2 6.3680 3.4 1.7 Cyg X-3 326.2560 38.5072 0.0 31.4 -179.2 -2.4647 -2.1 11.8 Cyg X-2 308.7583 -7.4394 3.8 32.1 77.5 6.1289 3.0 ------ UNKNOWN 11.5511 8.9950 2.5 34.5 -77.0 8.3959 4.6 ------ UNKNOWN 18.5808 8.1630 2.2 41.4 -76.2 18.9880 5.2 ------ UNKNOWN