GRB140817A: 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 Oct  4 21:06:48 EDT 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger609736
======================================================================

  Trigger: 00609736      Segment: 000

  BAT Trigger Time: 429951733.76   [s; MET]
      Trigger Stop: 429951734.784   [s; MET]
               UTC: 2014-08-17T07:02:01.353900    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 127.255706670156   Dec: 58.1893395054857  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    21.88
     Image Trigger?:     NO
     Rate S/N Ratio:     88.3345911860127  [ if not an image trigger ]
     Image S/N Ratio:    21.88

  Analysis Position:   [ source = BAT ]
    RA: 127.255706670156   Dec: 58.1893395054857  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 127.242430384116   Dec: 58.1908315406751  [deg; J2000]  
        { 08h 28m 58.2s , +58d 11' 27.0" }
         +/- 0.712907283861705 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.193263672856934 [arcmin] (formal 1-sigma fit error)
    SNR: 49.3254621336421
 
  Angular difference between the analysis and refined position is 0.429316 arcmin
 
  Partial Coding Fraction: 0.7578125    [ including projection effects ]

  Duration
     T90: 258.343999922276 +/- 17.0682669281408
        Measured from: -4.39599996805191
                   to: 253.947999954224     [s; relative to TRIGTIME]
     T50: 215.051999926567 +/- 2.33692103305643
        Measured from: 0.772000014781952
                   to: 215.823999941349     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 2.64399999380112     
                   to: 3.64399999380112     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -20.3280000090599     
                   to: 298.576000034809     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.955664   2.600225   2.043000   0.479939
           0.091197   0.094955   0.083445   0.073652 [error]
 Peak      0.145756   0.296217   0.319330   0.086289
           0.008188   0.010106   0.010420   0.007428 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  318.904  -20.328  298.576
T90   258.344   -4.396  253.948
T50   215.052    0.772  215.824
Peak    1.000    2.644    3.644
 
 
====== 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      -1.469    -0.078      0.078       -           -               -         1.48e-03     -6.11e-05          6.10e-05      52.790   57
CPL     -1.457    -0.088      0.248     2602.840    -2602.840      -2602.840      1.50e-03     -7.47e-05          4.74e-05      52.820   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: CPL)
 
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      -1.048     -0.062     0.062       -           -               -         6.03e-02     -2.23e-03          2.23e-03      58.620   57
CPL     -0.422     -0.266     0.283      146.259     -28.221        63.264      1.14e-01     -2.63e-02          3.64e-02      41.120   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   5.85e-07  1.09e-06  1.58e-06  4.86e-06  4.50e-06  8.12e-06   erg/cm2
      90%_error_low -4.57e-08 -5.01e-08 -8.41e-08 -5.61e-07 -2.02e-07 -6.16e-07   erg/cm2
      90%_error_hi   4.70e-08  4.99e-08  8.38e-08  6.11e-07  2.03e-07  6.57e-07   erg/cm2
Peak flux       PL   4.73e-04  7.21e-03  8.36e-02  7.29e+00  3.79e-01  7.31e+00   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   5.88e-07  1.09e-06  1.58e-06  5.03e-06  4.51e-06  7.90e-06   erg/cm2
      90%_error_low -6.54e-08 -3.85e-08 -8.18e-08 -1.71e-06 -2.48e-07 -1.35e-06   erg/cm2
      90%_error_hi   5.13e-08  5.86e-08  9.22e-08  1.52e-07  1.63e-07  8.37e-07   erg/cm2
Peak flux      CPL   1.36e+00  2.19e+00  2.22e+00  2.04e+00  6.81e+00  7.82e+00   ph/cm2/s
      90%_error_low -1.48e-01 -1.06e-01 -1.07e-01 -3.94e-01 -2.71e-01 -4.82e-01   ph/cm2/s
      90%_error_hi   1.52e-01  1.06e-01  1.08e-01  5.10e-01  2.71e-01  5.66e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  127.2424    58.1908   0.0039    31.0777   -27.3774         3.9212484     49.325 TRIG_00609736                 
 
Foreground time interval of the image:
-20.328  13.141 (delta_t =  33.469 [sec])
Background time interval of the image:
-424.659 -406.185 (delta_t =  18.475 [sec])
-239.760 -20.328 (delta_t = 219.432 [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  -20.328 sec. to  298.576 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.46886     ( -0.0779128   0.077997 )
Norm@50keV  : 1.47809E-03    ( -6.10598e-05   6.0989e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.79 using 59 PHA bins.
# Reduced chi-squared =         0.9261 for     57 degrees of freedom 
# Null hypothesis probability =   6.337330e-01
 
Photon flux (15-150 keV)    in 318.9 sec: 0.183026 ( -0.007964  0.007991 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.49588e-06 ( -2.02255e-07  2.02998e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -20.328 sec. to  298.576 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.46607     ( -0.0878969   0.248061 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 1.48276E-03    ( -6.13134e-05   6.07311e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.80 using 59 PHA bins.
# Reduced chi-squared =         0.9428 for     56 degrees of freedom 
# Null hypothesis probability =   5.969336e-01
 
Photon flux (15-150 keV)    in 318.9 sec: 0.183443 ( -0.009345  0.008465 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.508e-06 ( -2.4766e-07  1.63048e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    2.644 sec. to    3.644 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.04806     ( -0.062098   0.0624252 )
Norm@50keV  : 6.02843E-02    ( -0.00223215   0.00223086 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.62 using 59 PHA bins.
# Reduced chi-squared =          1.028 for     57 degrees of freedom 
# Null hypothesis probability =   4.157897e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.379390 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.41195e-07 ( -2.57064e-08  2.57653e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    2.644 sec. to    3.644 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.422173     ( -0.265599   0.282665 )
Epeak [keV] : 146.259      ( -28.221 63.2639 )
Norm@50keV  : 0.113998    ( -0.0263052   0.0364502 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          41.12 using 59 PHA bins.
# Reduced chi-squared =         0.7343 for     56 degrees of freedom 
# Null hypothesis probability =   9.318322e-01
 
Photon flux (15-150 keV)    in 1 sec: 6.80537 ( -0.27094  0.27111 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.2647e-07 ( -2.70931e-08  2.70216e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 258.344 sec.
Hardness ratio (energy fluence ratio) = 1.4451072754

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

S(15-50 keV)  = 1.6793663e-06
S(50-150 keV) = 2.81647e-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 = 5.352035358059961E-01, IMY = 2.771555482262377E-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:
-424.659400 -406.184600
-239.760000 -20.328000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
206.3212  -1.5874    3.4  58.3 -175.6   3.9366   3.4 ------	UNKNOWN                       
196.0964  -4.7981    3.5  59.3 -163.2   4.3632   3.3 ------	UNKNOWN                       

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

Time interval of the image:
-20.328000 13.140590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
243.4217  40.8871    2.5  41.1  114.1   1.1560   4.6 ------	UNKNOWN                       
 79.6382  74.0215    2.5  42.8    7.9   0.5521   4.6 ------	UNKNOWN                       
127.2424  58.1908    0.2  31.1  -27.4   3.9214  49.3 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
78.340580 962.320900
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6332  22.0177    0.5  47.7   -3.9  20.9207  22.6    0.2	Crab                          
 62.0761  66.8625    3.7  29.7   70.4   2.2394   3.1 ------	UNKNOWN                       
 73.3653  25.3037    3.4  49.9    9.0   3.7913   3.4 ------	UNKNOWN                       
207.3119  56.4873    3.1  40.7  172.9   2.6373   3.7 ------	UNKNOWN                       
195.4208  56.7307    2.4  35.1  178.6   2.6352   4.7 ------	UNKNOWN                       
127.2352  58.2099    1.2   0.1  119.1   4.1290   9.3 ------	UNKNOWN                       
209.4260  32.3856    3.2  59.0 -166.2  11.6842   3.7 ------	UNKNOWN                       
102.7481  13.5334    2.3  48.3  -31.0   5.0040   5.0 ------	UNKNOWN                       
112.3840   8.6608    3.9  50.8  -44.6   7.1467   3.0 ------	UNKNOWN