GRB171205A: Summary Image Light curves Spectra Distribution Others

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: Sat Jan 20 04:45:50 EST 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger794972
======================================================================

  Trigger: 00794972      Segment: 000

  BAT Trigger Time: 534151264   [s; MET]
      Trigger Stop: 534151328   [s; MET]
               UTC: 2017-12-05T07:20:43.893380    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 167.44703797704   Dec: -12.603638059632  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.46
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    9.46

  Analysis Position:   [ source = BAT ]
    RA: 167.44703797704   Dec: -12.603638059632  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 167.422495828668   Dec: -12.59909524997  [deg; J2000]  
        { 11h 09m 41.4s , -12d 35' 56.7" }
         +/- 1.59127441444509 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.692165751213049 [arcmin] (formal 1-sigma fit error)
    SNR: 15.6643047186403
 
  Angular difference between the analysis and refined position is 1.462679 arcmin
 
  Partial Coding Fraction: 0.4648438    [ including projection effects ]

  Duration
     T90: 190.471999943256 +/- 33.8808366621315
        Measured from: -26.1959999799728
                   to: 164.275999963284     [s; relative to TRIGTIME]
     T50: 88.9879999160767 +/- 18.8995519358928
        Measured from: -4.28799998760223
                   to: 84.6999999284744     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 49.0759999752045     
                   to: 50.0759999752045     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -42.227999985218     
                   to: 197.796000003815     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.383177   1.580667   1.745597   0.510485
           0.131022   0.136197   0.119369   0.102768 [error]
 Peak      0.047249   0.009614   0.044489  -0.004489
           0.010080   0.010277   0.009435   0.008064 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  240.024  -42.228  197.796
T90   190.472  -26.196  164.276
T50    88.988   -4.288   84.700
Peak    1.000   49.076   50.076
 
 
====== 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      -1.370    -0.135      0.136       -           -               -         1.51e-03     -1.14e-04          1.14e-04      61.420   57
CPL     -1.219    -0.271      0.565      295.335    -295.335      -295.335      1.77e-03     -3.56e-04          1.33e-03      61.170   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      -1.987     -0.815     0.589       -           -               -         6.39e-03     -2.79e-03          2.27e-03      63.760   57
CPL     -1.983     -0.824     0.590     9999.330    -9808.149      -9999.330      6.40e-03     -6.40e-03          -1.44e-03      63.760   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   4.10e-07  8.16e-07  1.26e-06  4.29e-06  3.53e-06  6.78e-06   erg/cm2
      90%_error_low -5.92e-08 -7.18e-08 -1.14e-07 -8.13e-07 -2.83e-07 -8.89e-07   erg/cm2
      90%_error_hi   6.21e-08  7.10e-08  1.13e-07  9.34e-07  2.84e-07  9.85e-07   erg/cm2
Peak flux       PL   4.21e-01  3.18e-01  1.60e-01  1.16e-01  9.53e-01  1.02e+00   ph/cm2/s
      90%_error_low -1.84e-01 -9.13e-02 -8.80e-02 -8.94e-02 -2.77e-01 -2.92e-01   ph/cm2/s
      90%_error_hi   2.10e-01  9.13e-02  8.07e-02  1.57e-01  2.77e-01  2.93e-01   ph/cm2/s
 
Fluence        CPL   3.95e-07  8.24e-07  1.28e-06  3.54e-06  3.51e-06  6.04e-06   erg/cm2
      90%_error_low -7.73e-08 -7.64e-08 -1.23e-07 -1.64e-06 -2.95e-07 -1.65e-06   erg/cm2
      90%_error_hi   6.81e-08  7.79e-08  1.37e-07  9.65e-07  2.94e-07  1.33e-06   erg/cm2
Peak flux      CPL   4.21e-01  6.93e-02  5.72e-03  6.25e-04  4.97e-01  4.98e-01   ph/cm2/s
      90%_error_low -2.10e-01 -6.93e-02 -5.72e-03 -6.25e-04 -2.74e-01     N/A     ph/cm2/s
      90%_error_hi   2.10e-01  2.30e-01  1.32e-01  1.05e-01  4.19e-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
  167.4225   -12.5991   0.0123    44.4511    -2.1899         3.9484566     15.664 TRIG_00794972                 
 
Foreground time interval of the image:
-42.228  73.101 (delta_t = 115.329 [sec])
Background time interval of the image:
-239.000 -42.228 (delta_t = 196.772 [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

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  -42.228 sec. to  197.796 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.37006     ( -0.135456   0.135959 )
Norm@50keV  : 1.51138E-03    ( -0.000113853   0.00011385 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.42 using 59 PHA bins.
# Reduced chi-squared =          1.078 for     57 degrees of freedom 
# Null hypothesis probability =   3.207276e-01
 
Photon flux (15-150 keV)    in 240 sec: 0.182849 ( -0.01479  0.014869 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.52754e-06 ( -2.83166e-07  2.84266e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -42.228 sec. to  197.796 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.21901     ( -0.271354   0.56451 )
Epeak [keV] : 295.335      ( -295.266 -295.266 )
Norm@50keV  : 1.76685E-03    ( -0.000356463   0.00132738 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.17 using 59 PHA bins.
# Reduced chi-squared =          1.092 for     56 degrees of freedom 
# Null hypothesis probability =   2.957016e-01
 
Photon flux (15-150 keV)    in 240 sec: 0.181299 ( -0.015704  0.015517 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.50518e-06 ( -2.94538e-07  2.93578e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   49.076 sec. to   50.076 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.98678     ( -0.814732   0.589035 )
Norm@50keV  : 6.39369E-03    ( -0.00278668   0.00227118 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.76 using 59 PHA bins.
# Reduced chi-squared =          1.119 for     57 degrees of freedom 
# Null hypothesis probability =   2.509096e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.953374 ( -0.276734  0.277036 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.89223e-08 ( -2.1058e-08  2.12289e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   49.076 sec. to   50.076 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -4.81387     ( -0.82393   0.589809 )
Epeak [keV] : 581.991      ( -9808.18 -9999.36 )
Norm@50keV  : 3.47817E-04    ( -0.00034788   0.00461241 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.74 using 59 PHA bins.
# Reduced chi-squared =          1.085 for     56 degrees of freedom 
# Null hypothesis probability =   3.090424e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.497018 ( -0.274357  0.419467 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.44791e-08 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 190.472 sec.
Hardness ratio (energy fluence ratio) = 1.54753316138

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

S(15-50 keV)  = 1.2261127e-06
S(50-150 keV) = 2.301421e-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 = 9.803048729764120E-01, IMY = 3.748571516028201E-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:
-239.000000 -42.228000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
138.0279  20.7088    2.6  41.5   64.5   3.5680   4.4 ------	UNKNOWN                       
258.7585  61.0913    2.8  57.9 -170.8   5.1627   4.2 ------	UNKNOWN                       
187.4881 -20.2437    3.2  49.6  -29.7   1.7769   3.6 ------	UNKNOWN                       
223.2529  14.4592    2.6  39.8 -101.4   3.5731   4.4 ------	UNKNOWN                       

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

Time interval of the image:
-42.228000 73.100600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
195.8344  49.1288    2.4  22.2  178.1   0.7017   4.8 ------	UNKNOWN                       
167.4225 -12.5991    0.7  44.5   -2.2   3.9479  15.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
133.900600 390.200600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.3492 -40.5724    5.0  39.6   18.4   0.8255   2.3    8.2	Vela X-1                      
170.1509 -60.5431   13.8  48.0  -22.6   0.3984   0.8    6.8	Cen X-3                       
186.6001 -62.7536    1.7  52.0  -31.8   4.9656   6.9    1.8	GX 301-2                      
133.9219  -7.2120    3.5  33.4   75.3   1.5117   3.3 ------	UNKNOWN                       
189.7934  21.2591    2.9  40.4 -167.6   1.4684   4.1 ------	UNKNOWN                       
187.2408   3.1709    2.1  25.2 -148.3   1.4257   5.5 ------	UNKNOWN                       
156.8158 -62.7379    2.3  50.7  -14.5   2.5040   5.0 ------	UNKNOWN                       
183.1800 -63.0180    2.5  51.6  -29.8   3.0898   4.6 ------	UNKNOWN                       
207.6761 -21.4346    4.1  39.3  -92.3   2.8049   2.8 ------	UNKNOWN