GRB120327A: 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: Mon Jan 13 05:07:52 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger518731
======================================================================

  Trigger: 00518731      Segment: 000

  BAT Trigger Time: 354509724.672   [s; MET]
      Trigger Stop: 354509726.72   [s; MET]
               UTC: 2012-03-27T02:55:16.636400    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 246.828429216695   Dec: -29.4152103588065  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.58
     Image Trigger?:     NO
     Rate S/N Ratio:     8.54400374531753  [ if not an image trigger ]
     Image S/N Ratio:    8.58

  Analysis Position:   [ source = BAT ]
    RA: 246.828429216695   Dec: -29.4152103588065  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 246.853607631327   Dec: -29.415974553381  [deg; J2000]  
        { 16h 27m 24.9s , -29d 24' 57.5" }
         +/- 1.13054096998853 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.302304866887127 [arcmin] (formal 1-sigma fit error)
    SNR: 25.5267242182291
 
  Angular difference between the analysis and refined position is 1.316744 arcmin
 
  Partial Coding Fraction: 0.765625    [ including projection effects ]

  Duration
     T90: 63.5319999456406 +/- 7.02858390816799
        Measured from: -6.99199998378754
                   to: 56.539999961853     [s; relative to TRIGTIME]
     T50: 23.3199999332428 +/- 3.6518094364959
        Measured from: 16.5080000162125
                   to: 39.8279999494553     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 37.1560000181198     
                   to: 38.1560000181198     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -15.7879999876022     
                   to: 74.5760000348091     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.622277   2.191554   1.653380   0.388241
           0.065214   0.058687   0.049830   0.040467 [error]
 Peak      0.112790   0.171048   0.170675   0.041656
           0.008195   0.008481   0.007837   0.005472 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   90.364  -15.788   74.576
T90    63.532   -6.992   56.540
T50    23.320   16.508   39.828
Peak    1.000   37.156   38.156
 
 
====== 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      -1.517    -0.061      0.061       -           -               -         4.18e-03     -1.34e-04          1.34e-04      53.580   57
CPL     -1.361    -0.188      0.239      217.673     -99.902      -217.673      4.95e-03     -8.53e-04          1.42e-03      52.200   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      -1.251     -0.091     0.092       -           -               -         3.28e-02     -1.67e-03          1.67e-03      59.570   57
CPL     -1.090     -0.205     0.360      316.457    -316.457      -316.457      3.89e-02     -7.36e-03          1.73e-02      58.910   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   4.90e-07  8.91e-07  1.25e-06  3.64e-06  3.57e-06  6.27e-06   erg/cm2
      90%_error_low -3.07e-08 -3.25e-08 -5.07e-08 -3.28e-07 -1.22e-07 -3.58e-07   erg/cm2
      90%_error_hi   3.15e-08  3.23e-08  5.05e-08  3.50e-07  1.22e-07  3.76e-07   erg/cm2
Peak flux       PL   1.06e+00  1.24e+00  1.04e+00  1.48e+00  3.88e+00  4.83e+00   ph/cm2/s
      90%_error_low -1.05e-01 -7.53e-02 -6.23e-02 -1.82e-01 -2.06e-01 -2.56e-01   ph/cm2/s
      90%_error_hi   1.09e-01  7.48e-02  6.19e-02  1.98e-01  2.06e-01  2.58e-01   ph/cm2/s
 
Fluence        CPL   4.73e-07  9.01e-07  1.26e-06  2.91e-06  3.53e-06  5.54e-06   erg/cm2
      90%_error_low -3.87e-08 -3.52e-08 -5.46e-08 -7.85e-07 -1.37e-07 -7.94e-07   erg/cm2
      90%_error_hi   3.94e-08  3.55e-08  5.51e-08  8.32e-07  1.37e-07  8.64e-07   erg/cm2
Peak flux      CPL   8.67e-01  6.70e-01  3.62e-01  3.41e-01  2.04e+00  2.24e+00   ph/cm2/s
      90%_error_low -1.41e-01 -7.10e-02 -5.97e-02 -3.81e-02 -1.86e-01 -1.37e-01   ph/cm2/s
      90%_error_hi   7.48e-02  3.37e-02  5.32e-02  3.10e-02  1.42e-01  3.45e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  246.8536   -29.4160   0.0075    17.0697    76.1983         2.1313812     25.527 TRIG_00518731                 
 
Foreground time interval of the image:
-15.788  25.829 (delta_t =  41.617 [sec])
Background time interval of the image:
-239.672 -15.788 (delta_t = 223.884 [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  -15.788 sec. to   74.576 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.51715     ( -0.061371   0.0613644 )
Norm@50keV  : 4.17984E-03    ( -0.000133985   0.000133933 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.58 using 59 PHA bins.
# Reduced chi-squared =         0.9400 for     57 degrees of freedom 
# Null hypothesis probability =   6.042110e-01
 
Photon flux (15-150 keV)    in 90.36 sec: 0.524266 ( -0.018298  0.018355 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.5736e-06 ( -1.22115e-07  1.22434e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -15.788 sec. to   74.576 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.36064     ( -0.188044   0.239044 )
Epeak [keV] : 217.673      ( -99.8911 -217.662 )
Norm@50keV  : 4.95241E-03    ( -0.00085327   0.00141561 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.20 using 59 PHA bins.
# Reduced chi-squared =         0.9322 for     56 degrees of freedom 
# Null hypothesis probability =   6.193590e-01
 
Photon flux (15-150 keV)    in 90.36 sec: 0.518265 ( -0.020133  0.020189 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.53034e-06 ( -1.37398e-07  1.36876e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   37.156 sec. to   38.156 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.25088     ( -0.0914288   0.0916066 )
Norm@50keV  : 3.27912E-02    ( -0.00167073   0.00167073 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.57 using 59 PHA bins.
# Reduced chi-squared =          1.045 for     57 degrees of freedom 
# Null hypothesis probability =   3.823442e-01
 
Photon flux (15-150 keV)    in 1 sec: 3.87890 ( -0.20573  0.20604 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.28133e-07 ( -1.8441e-08  1.8516e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   37.156 sec. to   38.156 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.09021     ( -0.205257   0.360429 )
Epeak [keV] : 316.457      ( -316.454 -316.454 )
Norm@50keV  : 3.88546E-02    ( -0.00735973   0.017306 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.91 using 59 PHA bins.
# Reduced chi-squared =          1.052 for     56 degrees of freedom 
# Null hypothesis probability =   3.694034e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.03642 ( -0.18552  0.14172 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.25402e-07 ( -1.94805e-08  1.93843e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 63.532 sec.
Hardness ratio (energy fluence ratio) = 1.39752660962

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

S(15-50 keV)  = 1.3812833e-06
S(50-150 keV) = 2.1923324e-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 = 7.325308810734436E-02, IMY = -2.981952685723963E-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:
-239.672000 -15.788000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9772 -15.6444    0.2  23.8  111.8  14.4818  47.3    0.3	Sco X-1                       
255.8268 -37.9660    5.2  12.6   34.2   0.4711   2.2   10.5	4U 1700-377                   
256.4067 -36.3299    2.3  11.2   38.8   1.0461   4.9    5.8	GX 349+2                      
262.9963 -24.6576    5.8   5.3  136.4   0.4178   2.0    5.3	GX 1+4                        
264.9746 -44.3229    0.0  15.4   -3.7  -0.0230  -0.1   12.5	4U 1735-44                    
268.3471  -1.3687    3.0  27.7  176.6   0.9020   3.9    5.2	SW J1753.5-0127               
270.4486 -25.0937    6.4   5.3 -144.0   0.3714   1.8    9.0	GX 5-1                        
270.2273 -25.8615    4.5   4.6 -139.5   0.5251   2.6    8.2	GRS 1758-258                  
273.9379 -14.0446    5.0  16.5 -161.0   0.5184   2.3    4.0	GX 17+2                       
275.9373 -30.5161    5.8   8.4  -84.8   0.4172   2.0    9.0	H1820-303                     
285.0191 -25.0329   21.9  17.0 -106.6   0.1213   0.5    6.8	HT1900.1-2455                 
288.7889  10.9437    1.5  45.4 -155.9   3.4855   7.8    0.6	GRS 1915+105                  
262.8176 -33.7806    6.4   5.7   24.2   0.4166   1.8    9.1	GX 354-0                      
277.3319 -23.8156    2.6  11.0 -123.0   0.9038   4.4 ------	UNKNOWN                       
290.5611  13.0709    3.4  48.1 -155.2   1.7219   3.4 ------	UNKNOWN                       
300.5577 -11.1389    3.3  36.5 -119.8   1.3069   3.5 ------	UNKNOWN                       
305.8264   0.7545    2.7  48.0 -128.9   4.3753   4.2 ------	UNKNOWN                       

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

Time interval of the image:
-15.788000 25.828590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9063 -15.7443    2.5  23.8  111.5  -0.4630  -4.6    7.5	Sco X-1                       
256.0102 -38.0022    4.3  12.5   33.6  -0.1824  -2.6    9.6	4U 1700-377                   
256.2309 -36.4804    4.8  11.4   38.6  -0.1715  -2.4   10.5	GX 349+2                      
262.8696 -24.5926    7.8   5.4  135.8  -0.1036  -1.5   11.9	GX 1+4                        
264.9718 -44.3364    5.5  15.4   -3.7   0.1545   2.1   11.9	4U 1735-44                    
268.3657  -1.4499    9.4  27.6  176.6  -0.1019  -1.2    0.2	SW J1753.5-0127               
270.2907 -25.0744 1596.5   5.2 -145.4  -0.0005  -0.0    0.5	GX 5-1                        
270.3024 -25.7430   19.8   4.7 -140.0  -0.0439  -0.6    0.0	GRS 1758-258                  
274.0855 -14.1939    6.1  16.4 -160.4  -0.1404  -1.9   10.5	GX 17+2                       
275.7604 -30.2112    0.0   8.2  -86.7  -0.0574  -0.8   12.7	H1820-303                     
284.8881 -24.8278    4.8  17.0 -107.4   0.1870   2.4    9.8	HT1900.1-2455                 
288.7878  10.9948    4.6  45.4 -156.0  -0.3454  -2.5    3.0	GRS 1915+105                  
262.7824 -33.9578    0.0   5.9   23.5  -0.0729  -1.0   12.7	GX 354-0                      
246.8536 -29.4160    0.5  17.1   76.2   2.1313  25.5 ------	UNKNOWN                       
268.9135  28.0098    2.9  57.0  175.0   1.8436   4.0 ------	UNKNOWN                       
280.9458  10.2701    2.0  41.7 -165.8   0.6434   5.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
64.828600 962.388200
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
186.7111 -62.7965   10.0  50.6   18.1   2.4016   1.2    2.2	GX 301-2                      
244.9785 -15.6412    0.2  13.9  159.7  45.6188  73.3    0.1	Sco X-1                       
255.9839 -37.8182    2.6  11.3  -52.5   2.4795   4.4    1.6	4U 1700-377                   
256.3769 -36.3012    5.2  10.5  -59.6   1.2741   2.2    7.8	GX 349+2                      
262.9029 -24.7231    5.0  15.0 -117.2   1.5032   2.3    5.9	GX 1+4                        
264.7484 -44.3058    5.3  20.6  -51.5   1.3712   2.2    8.7	4U 1735-44                    
268.3721  -1.4091    3.6  34.7 -152.6   2.5327   3.1    2.6	SW J1753.5-0127               
270.3010 -25.0610    2.3  21.3 -109.0   3.3822   5.1    1.4	GX 5-1                        
270.3596 -25.7156    4.3  21.1 -107.2   1.8627   2.7    3.5	GRS 1758-258                  
274.0459 -13.9312    3.3  29.5 -128.6   3.0972   3.5    6.7	GX 17+2                       
275.8976 -30.4210    2.2  25.1  -93.2   4.5263   5.3    3.5	H1820-303                     
284.8544 -24.8034    0.0  34.0 -101.3  -1.8574  -1.5   12.1	HT1900.1-2455                 
263.1539 -33.7656   13.6  14.5  -81.2   0.5467   0.8    9.2	GX 354-0                      
187.5145 -44.8249    2.2  48.6   41.7  16.4029   5.3 ------	UNKNOWN                       
208.0751 -52.5224    2.8  36.6   27.0   4.2792   4.1 ------	UNKNOWN                       
202.8764 -56.9757    3.9  41.1   22.4   3.3397   3.0 ------	UNKNOWN                       
227.0525 -70.9469    4.0  43.0   -3.4   3.1449   2.9 ------	UNKNOWN                       
284.5283 -68.8385    3.7  45.0  -30.9   3.8443   3.2 ------	UNKNOWN