GRB181023A

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 Dec 17 17:11:02 EST 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger868427
======================================================================

  Trigger: 00868427      Segment: 000

  BAT Trigger Time: 561953064   [s; MET]
      Trigger Stop: 561953160   [s; MET]
               UTC: 2018-10-23T02:04:02.201780    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 248.328741900568   Dec: 19.564150818638  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.13
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    7.13

  Analysis Position:   [ source = BAT ]
    RA: 248.328741900568   Dec: 19.564150818638  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 248.324883995465   Dec: 19.5781622938717  [deg; J2000]  
        { 16h 33m 18.0s , +19d 34' 41.4" }
         +/- 1.99455718922227 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.03550434088403 [arcmin] (formal 1-sigma fit error)
    SNR: 11.3440007578389
 
  Angular difference between the analysis and refined position is 0.868519 arcmin
 
  Partial Coding Fraction: 0.515625    [ including projection effects ]

  Duration
     T90: 56.9839998483658 +/- 8.03310270984739
        Measured from: -21.4119999408722
                   to: 35.5719999074936     [s; relative to TRIGTIME]
     T50: 35.5999999046326 +/- 8.24235794592534
        Measured from: -7.55599999427795
                   to: 28.0439999103546     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 32.1840000152588     
                   to: 33.1840000152588     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -29.0160000324249     
                   to: 36.9400000572205     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.667064   0.775392   0.588418   0.112958
           0.105407   0.090893   0.076592   0.068049 [error]
 Peak      0.043308   0.031396   0.029800   0.011832
           0.012742   0.011109   0.009485   0.008271 [error]

     [ fluence units of on-axis counts / fully illuminated detector ] 

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   65.956  -29.016   36.940
T90    56.984  -21.412   35.572
T50    35.600   -7.556   28.044
Peak    1.000   32.184   33.184
 
 
====== 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: 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      -1.722    -0.241      0.236       -           -               -         2.14e-03     -2.90e-04          2.87e-04      71.770   57
CPL     -1.551    -0.834      0.981      129.856    -129.856      -129.856      2.62e-03     -7.57e-04          5.33e-03      71.650   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      -1.949     -0.681     0.606       -           -               -         6.74e-03     -2.55e-03          2.34e-03      50.380   57
CPL     -1.941     -1.673     1.885      350.793      N/A           N/A         6.82e-03        N/A               N/A         50.380   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   2.22e-07  3.56e-07  4.32e-07  1.03e-06  1.30e-06  2.04e-06   erg/cm2
      90%_error_low -4.80e-08 -4.81e-08 -7.75e-08 -3.45e-07 -1.82e-07 -4.17e-07   erg/cm2
      90%_error_hi   5.10e-08  4.77e-08  7.71e-08  4.49e-07  1.84e-07  4.95e-07   erg/cm2
Peak flux       PL   4.28e-01  3.31e-01  1.71e-01  1.28e-01  9.89e-01  1.06e+00   ph/cm2/s
      90%_error_low -2.00e-01 -1.02e-01 -8.17e-02 -8.95e-02 -3.10e-01 -3.22e-01   ph/cm2/s
      90%_error_hi   2.26e-01  1.01e-01  8.17e-02  1.68e-01  3.12e-01  3.22e-01   ph/cm2/s
 
Fluence        CPL   2.16e-07  3.62e-07  4.36e-07  7.88e-07  1.29e-06  1.80e-06   erg/cm2
      90%_error_low -5.77e-08 -5.34e-08 -8.01e-08 -5.51e-07 -2.01e-07 -6.01e-07   erg/cm2
      90%_error_hi   5.12e-08  5.75e-08  8.28e-08  3.29e-07  1.96e-07  3.93e-07   erg/cm2
Peak flux      CPL   4.37e-01  3.21e-01  1.61e-01  1.35e-01  9.69e-01  1.04e+00   ph/cm2/s
      90%_error_low     N/A   -1.78e-01 -7.11e-02 -7.76e-02     N/A   -5.74e-01   ph/cm2/s
      90%_error_hi      N/A    1.10e-01  6.30e-02  4.52e-02     N/A    3.57e-01   ph/cm2/s
 
======================================================================

Special notes of this burst

Image

Pre-slew 15.0-350.0 keV image (Event data)

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  248.3249    19.5782   0.0169    40.1231   -25.5672         2.0245601     11.344 TRIG_00868427                 
 
Foreground time interval of the image:
-16.299  36.940 (delta_t =  53.239 [sec])
Background time interval of the image:

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

Bokeh Plot

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

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

Time interval is from  -29.016 sec. to   36.940 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.72205     ( -0.240581   0.236162 )
Norm@50keV  : 2.14004E-03    ( -0.000290052   0.00028677 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          71.77 using 59 PHA bins.
# Reduced chi-squared =          1.259 for     57 degrees of freedom 
# Null hypothesis probability =   9.011103e-02
 
Photon flux (15-150 keV)    in 65.96 sec: 0.286459 ( -0.038827  0.039046 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.305e-06 ( -1.82152e-07  1.84022e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from  -29.016 sec. to   36.940 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.55058     ( -0.833897   0.980561 )
Epeak [keV] : 129.856      ( -129.854 -129.854 )
Norm@50keV  : 2.61513E-03    ( -0.000756533   0.00533001 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          71.65 using 59 PHA bins.
# Reduced chi-squared =          1.279 for     56 degrees of freedom 
# Null hypothesis probability =   7.760368e-02
 
Photon flux (15-150 keV)    in 65.96 sec: 0.283707 ( -0.04118  0.038446 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.28793e-06 ( -2.01076e-07  1.96163e-07 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from   32.184 sec. to   33.184 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.94931     ( -0.681477   0.605855 )
Norm@50keV  : 6.74221E-03    ( -0.00255052   0.00234089 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.38 using 59 PHA bins.
# Reduced chi-squared =         0.8838 for     57 degrees of freedom 
# Null hypothesis probability =   7.199909e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.988544 ( -0.309954  0.312156 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.20555e-08 ( -2.11379e-08  2.19176e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   32.184 sec. to   33.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.94072     ( -1.66945   1.88835 )
Epeak [keV] : 350.793      (   )
Norm@50keV  : 6.81968E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.38 using 59 PHA bins.
# Reduced chi-squared =         0.8997 for     56 degrees of freedom 
# Null hypothesis probability =   6.865754e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.969311 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.28507e-08 ( -5.96119e-08  1.83594e-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 = 7.602424147215958E-01, IMY = 3.637123024316146E-01

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:

Pre-slew background subtracted image of 15-350 keV band

Time interval of the image:
-16.299400 36.940000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9754 -15.6418    0.3  13.8  -87.3   4.3709  35.0    0.3	Sco X-1                       
254.3446  35.3516 1393.0  54.7  -14.5   0.0030   0.0    5.6	Her X-1                       
256.0151 -37.8110    2.3  18.8  177.5   0.6217   5.2    2.4	4U 1700-377                   
256.2243 -36.5429    0.0  17.6  177.5   0.2658   2.1   12.5	GX 349+2                      
263.1946 -24.6284   11.8   6.7  135.4   0.1154   1.0   12.3	GX 1+4                        
264.5437 -44.4747    7.0  25.7  161.0   0.2372   1.7    8.7	4U 1735-44                    
268.4845  -1.5218    6.7  19.9   19.0  -0.2020  -1.7    8.1	SW J1753.5-0127               
270.3208 -25.1110    2.8  12.1  111.8   0.5202   4.1    2.8	GX 5-1                        
270.3173 -25.8919    4.2  12.4  115.0   0.3541   2.7    9.0	GRS 1758-258                  
274.0601 -14.0918    8.1  15.3   63.1   0.1804   1.4    4.6	GX 17+2                       
275.7613 -30.2671   18.7  18.8  119.6   0.0880   0.6   10.4	H1820-303                     
285.1554 -24.7973   62.6  24.9   98.0   0.0321   0.2    9.8	HT1900.1-2455                 
288.8379  10.8842  127.3  42.0   37.0   0.0264   0.1    4.4	GRS 1915+105                  
263.0994 -33.9026    5.6  15.2  157.0   0.2443   2.1    6.8	GX 354-0                      
292.1084 -64.1034    2.4  50.2  152.0   2.4310   4.8 ------	UNKNOWN                       
248.3249  19.5781    1.0  40.1  -25.6   2.0240  11.3 ------	UNKNOWN                       
241.6229  26.0463    2.1  48.2  -30.9   1.6227   5.4 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
179.100600 963.088300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9897 -15.6371    0.2  35.4 -140.2  53.7091  46.8    0.6	Sco X-1                       
254.3610  35.4516    3.7  16.8   51.7   2.6197   3.1    8.1	Her X-1                       
256.3854 -36.3199   47.2  56.4 -153.5  -0.9692  -0.2    6.6	GX 349+2                      
263.0069 -24.7461   99.1  46.6 -164.2   0.1941   0.1    0.1	GX 1+4                        
268.3862  -1.4433   12.3  28.8  168.9   0.9461   0.9    1.2	SW J1753.5-0127               
270.3366 -24.9817    5.9  49.4 -172.3   3.7497   2.0    6.5	GX 5-1                        
270.4286 -25.7392    8.2  50.2 -171.9   2.8961   1.4    6.8	GRS 1758-258                  
274.0061 -14.2173   11.7  42.2  175.6   1.6382   1.0   10.9	GX 17+2                       
275.9196 -30.3699 1210.4  56.6 -174.3  -0.0336  -0.0    0.3	H1820-303                     
288.8420  11.0147    4.2  39.9  130.5   5.8880   2.7    4.9	GRS 1915+105                  
263.0158 -33.7822    4.7  55.2 -160.6   7.3314   2.4    3.4	GX 354-0                      
285.9008  26.9382    5.0  35.2  105.0   4.4236   2.3 ------	UNKNOWN                       
282.7712  30.1914    3.0  32.9   98.6   6.0851   3.9 ------	UNKNOWN                       
275.9674  27.7110    3.8  26.6  101.2   3.8724   3.1 ------	UNKNOWN                       
190.8864  58.9659    3.3  56.7    3.0  13.4386   3.4 ------	UNKNOWN

Analysis Summary

Notes:

Image

Pre-slew 15.0-350.0 keV image (Event data)

Light Curves

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

Notes:

Time averaged spectrum fit using the average DRM

Power-law model

Cutoff power-law model

1-s peak spectrum fit

Power-law model

Cutoff power-law model

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

S(15-50 keV) vs. S(50-150 keV) plot

Mask shadow pattern

Spacecraft aspect plot

Bright source in the pre-burst/pre-slew/post-slew images

Pre-burst image of 15-350 keV band

Pre-slew background subtracted image of 15-350 keV band

Post-slew image of 15-350 keV band

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