GRB140518A: 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 22:45:12 EDT 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger599287
======================================================================

  Trigger: 00599287      Segment: 000

  BAT Trigger Time: 422097478.656   [s; MET]
      Trigger Stop: 422097479.68   [s; MET]
               UTC: 2014-05-18T09:17:46.630720    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 227.269331468707   Dec: 42.4156655750532  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.66
     Image Trigger?:     NO
     Rate S/N Ratio:     13.7477270848675  [ if not an image trigger ]
     Image S/N Ratio:    8.66

  Analysis Position:   [ source = BAT ]
    RA: 227.269331468707   Dec: 42.4156655750532  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 227.221166823231   Dec: 42.3998493646802  [deg; J2000]  
        { 15h 08m 53.1s , +42d 23' 59.5" }
         +/- 1.72249157659234 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.824997164495074 [arcmin] (formal 1-sigma fit error)
    SNR: 13.987853804574
 
  Angular difference between the analysis and refined position is 2.335289 arcmin
 
  Partial Coding Fraction: 0.890625    [ including projection effects ]

  Duration
     T90: 60.5239999294281 +/- 2.48237949745235
        Measured from: -2.64800000190735
                   to: 57.8759999275208     [s; relative to TRIGTIME]
     T50: 48.4039999246597 +/- 3.51867079527506
        Measured from: 3.7960000038147
                   to: 52.1999999284744     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 41.944000005722     
                   to: 42.944000005722     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -3.98000001907349     
                   to: 60.039999961853     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.763584   0.884923   0.457812   0.007289
           0.044780   0.046801   0.041729   0.038926 [error]
 Peak      0.036478   0.054534   0.028957   0.005231
           0.005941   0.006190   0.005503   0.004835 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   64.020   -3.980   60.040
T90    60.524   -2.648   57.876
T50    48.404    3.796   52.200
Peak    1.000   41.944   42.944
 
 
====== 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: 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      -1.892    -0.123      0.120       -           -               -         1.99e-03     -1.55e-04          1.53e-04      61.540   57
CPL     -0.977    -0.534      0.611       47.922      -7.115        12.667      6.48e-03     -3.18e-03          7.73e-03      52.190   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      -1.591     -0.233     0.226       -           -               -         7.55e-03     -1.18e-03          1.16e-03      56.200   57
CPL      0.253     -1.187     1.614       52.687      -9.532        22.807      8.20e-02     -8.20e-02          5.79e-01      48.120   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   2.35e-07  3.40e-07  3.67e-07  7.36e-07  1.17e-06  1.68e-06   erg/cm2
      90%_error_low -2.23e-08 -2.18e-08 -3.90e-08 -1.47e-07 -8.94e-08 -1.89e-07   erg/cm2
      90%_error_hi   2.28e-08  2.18e-08  3.95e-08  1.70e-07  9.07e-08  2.07e-07   erg/cm2
Peak flux       PL   3.39e-01  3.23e-01  2.15e-01  2.22e-01  9.67e-01  1.10e+00   ph/cm2/s
      90%_error_low -6.91e-02 -4.60e-02 -4.21e-02 -7.37e-02 -1.36e-01 -1.61e-01   ph/cm2/s
      90%_error_hi   7.20e-02  4.60e-02  4.25e-02  9.36e-02  1.36e-01  1.63e-01   ph/cm2/s
 
Fluence        CPL   2.13e-07  3.74e-07  3.54e-07  1.88e-07  1.06e-06  1.13e-06   erg/cm2
      90%_error_low -2.61e-08 -2.92e-08 -4.67e-08 -9.58e-08 -9.96e-08 -1.40e-07   erg/cm2
      90%_error_hi   2.62e-08  2.98e-08  4.53e-08  2.00e-07  1.05e-07  2.23e-07   erg/cm2
Peak flux      CPL   2.77e-01  3.95e-01  2.14e-01  3.34e-02  9.14e-01  9.19e-01   ph/cm2/s
      90%_error_low -8.24e-02 -6.48e-02 -5.68e-02 -3.34e-02 -1.38e-01 -1.41e-01   ph/cm2/s
      90%_error_hi   8.38e-02  6.83e-02  5.34e-02  7.05e-02  1.39e-01  1.47e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  227.2212    42.3998   0.0137    20.2239   -44.0843         0.6854120     13.988 TRIG_00599287                 
 
Foreground time interval of the image:
 -3.980  15.845 (delta_t =  19.825 [sec])
Background time interval of the image:
-347.555 -328.358 (delta_t =  19.197 [sec])
-239.656  -3.980 (delta_t = 235.676 [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   -3.980 sec. to   60.040 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.89241     ( -0.123189   0.11978 )
Norm@50keV  : 1.98641E-03    ( -0.000154752   0.000152903 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.54 using 59 PHA bins.
# Reduced chi-squared =          1.080 for     57 degrees of freedom 
# Null hypothesis probability =   3.168509e-01
 
Photon flux (15-150 keV)    in 64.02 sec: 0.284174 ( -0.018357  0.018366 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.1693e-06 ( -8.93694e-08  9.07151e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -3.980 sec. to   60.040 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.976957     ( -0.533886   0.610629 )
Epeak [keV] : 47.9220      ( -7.11486 12.6666 )
Norm@50keV  : 6.47742E-03    ( -0.00318066   0.00772819 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.19 using 59 PHA bins.
# Reduced chi-squared =         0.9320 for     56 degrees of freedom 
# Null hypothesis probability =   6.196861e-01
 
Photon flux (15-150 keV)    in 64.02 sec: 0.271789 ( -0.019498  0.019537 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.06394e-06 ( -9.95613e-08  1.04556e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   41.944 sec. to   42.944 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.59072     ( -0.233043   0.226079 )
Norm@50keV  : 7.54577E-03    ( -0.00117998   0.00116423 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.20 using 59 PHA bins.
# Reduced chi-squared =         0.9860 for     57 degrees of freedom 
# Null hypothesis probability =   5.048981e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.966930 ( -0.136394  0.13641 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.06627e-08 ( -1.17865e-08  1.2082e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   41.944 sec. to   42.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.252708     ( -1.18739   1.61398 )
Epeak [keV] : 52.6871      ( -9.53155 22.8073 )
Norm@50keV  : 8.19976E-02    ( -0.0819987   0.57938 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          48.12 using 59 PHA bins.
# Reduced chi-squared =         0.8593 for     56 degrees of freedom 
# Null hypothesis probability =   7.639405e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.914342 ( -0.137996  0.138968 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.9826e-08 ( -1.13206e-08  1.29352e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 60.524 sec.
Hardness ratio (energy fluence ratio) = 0.944691585381

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

S(15-50 keV)  = 5.869978e-07
S(50-150 keV) = 4.76948e-07

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 = 2.646293617018872E-01, IMY = 2.563029369990332E-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:
-347.555400 -328.357900
-239.656000 -3.980000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3948  35.2239 1020.3  35.7   -8.2  -0.0030  -0.0    7.7	Her X-1                       
231.1928 -10.9385    2.5  39.5   81.6   4.4701   4.6 ------	UNKNOWN                       
254.4651   3.2678    2.7  44.2   40.9   2.7306   4.2 ------	UNKNOWN                       
158.4590   2.6858    4.2  58.3 -175.3   3.5521   2.7 ------	UNKNOWN                       
169.3986  13.2584    2.8  44.0 -169.1   1.3999   4.2 ------	UNKNOWN                       
154.3536   9.4331    2.6  59.1 -166.2   6.0358   4.5 ------	UNKNOWN                       
236.9796  67.7238    3.6  44.8  -60.3   2.7937   3.2 ------	UNKNOWN                       

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

Time interval of the image:
-3.980000 15.844600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.2741  35.3349   14.2  35.6   -8.4  -0.0494  -0.8    9.0	Her X-1                       
227.2211  42.3999    0.8  20.2  -44.1   0.6854  14.0 ------	UNKNOWN                       
273.4739  39.6407    2.0  50.9  -14.0   0.6817   5.6 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
57.244600 962.395800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3852  35.2431    7.9  22.2   18.3  -0.7762  -1.5    6.9	Her X-1                       
299.5846  35.1971    0.7  55.1   -9.8  28.3686  17.6    0.4	Cyg X-1                       
308.1136  41.1622   31.3  57.8  -20.1   0.9926   0.4   12.6	Cyg X-3                       
277.9196  19.1774    3.0  48.4   21.0   5.9025   3.9 ------	UNKNOWN                       
230.7646  32.5387    2.8  10.2   81.7   2.0016   4.1 ------	UNKNOWN                       
241.7830  34.8364    3.0  13.6   37.5   1.7633   3.9 ------	UNKNOWN                       
215.1020  53.3666    2.0  13.6 -113.8   2.9333   5.7 ------	UNKNOWN                       
305.9701  69.7094    3.9  46.9  -53.8   8.0414   3.0 ------	UNKNOWN