GRB131120A

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 11 22:12:16 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger578227
======================================================================

  Trigger: 00578227      Segment: 000

  BAT Trigger Time: 406651088   [s; MET]
      Trigger Stop: 406651152   [s; MET]
               UTC: 2013-11-20T14:37:56.703060    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 278.921458952195   Dec: -11.9973317222608  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.8
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    7.8

  Analysis Position:   [ source = BAT ]
    RA: 278.921458952195   Dec: -11.9973317222608  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 278.921   Dec: -11.9973  [deg; J2000]
        { 18h 35m 41.0s , -11d -59' -50.3" }
        +/- 2.85584839428 [arcmin] (estimated 90% radius based on SNR)
    SNR: 6.79399128103
 
 
  Angular difference between the analysis and refined position is 0.027003 arcmin
 
  Partial Coding Fraction: 0.5078125    [ including projection effects ]

  Duration
     T90: 130.431999981403 +/- 21.3031813750126
        Measured from: -68.4079999923706
                   to: 62.0239999890327     [s; relative to TRIGTIME]
     T50: 92.6080000400543 +/- 16.5377783557849
        Measured from: -42.744000017643
                   to: 49.8640000224113     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 49.3960000276566     
                   to: 50.3960000276566     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -71.0960000157356     
                   to: 64.2639999985695     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.694098   0.490425   0.059813  -0.048320
           0.097986   0.096745   0.082379   0.073002 [error]
 Peak      0.023105   0.020669   0.015756   0.007779
           0.008490   0.008141   0.007314   0.005887 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  135.360  -71.096   64.264
T90   130.432  -68.408   62.024
T50    92.608  -42.744   49.864
Peak    1.000   49.396   50.396
 
 
====== 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      -2.873    -0.520      0.429       -           -               -         3.95e-04     -1.52e-04          1.62e-04      69.290   57
CPL     -0.785     N/A        N/A          17.078      N/A           N/A         1.17e-02        N/A               N/A         66.930   56
 
 
=== 1-s peak 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      -1.627     -0.704     0.706       -           -               -         4.18e-03     -1.70e-03          1.64e-03      39.650   57
CPL     -1.516     -1.174     4.281      183.103    -183.103      -183.103      4.86e-03     -4.86e-03          -4.86e-03      39.670   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   2.53e-07  2.04e-07  1.12e-07  8.92e-08  6.09e-07  6.58e-07   erg/cm2
      90%_error_low -5.38e-08 -5.40e-08 -5.23e-08 -5.88e-08 -1.46e-07 -1.76e-07   erg/cm2
      90%_error_hi   5.40e-08  5.21e-08  6.53e-08  1.16e-07  1.57e-07  2.18e-07   erg/cm2
Peak flux       PL   1.94e-01  1.81e-01  1.17e-01  1.17e-01  5.42e-01  6.11e-01   ph/cm2/s
      90%_error_low -1.14e-01 -7.51e-02 -5.81e-02 -1.17e-01 -2.12e-01 -2.32e-01   ph/cm2/s
      90%_error_hi   1.31e-01  7.22e-02  5.76e-02  1.63e-01  2.13e-01  2.33e-01   ph/cm2/s
 
Fluence        CPL   2.54e-07  2.12e-07  1.12e-07  1.00e-07  6.19e-07  6.66e-07   erg/cm2
      90%_error_low -7.14e-08 -5.56e-08 -5.28e-08    N/A    -1.53e-07    N/A      erg/cm2
      90%_error_hi   5.15e-08  5.91e-08  6.52e-08    N/A     1.48e-07    N/A      erg/cm2
Peak flux      CPL   1.95e-01  1.81e-01  1.17e-01  1.18e-01  5.41e-01  6.12e-01   ph/cm2/s
      90%_error_low -1.19e-01 -7.33e-02 -5.77e-02 -1.18e-01 -2.10e-01 -2.34e-01   ph/cm2/s
      90%_error_hi   1.31e-01  1.43e-01  6.17e-02  1.61e-01  2.13e-01  2.30e-01   ph/cm2/s
 
======================================================================

Special notes of this burst

Image

Pre-slew 15.0-50.0 keV image (Event data)

#RAcent DECcent POSerr Theta  Phi  Peak_Cts  SNR Name
278.921 -11.997 0.000 38.085 -33.956 0.693 6.794 TRIG_00578227
 
Image time interval: 0.000 to 64.000 [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

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  -71.096 sec. to   64.264 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.87316     ( -0.520459   0.429281 )
Norm@50keV  : 3.95458E-04    ( -0.000151789   0.00016163 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.29 using 59 PHA bins.
# Reduced chi-squared =          1.216 for     57 degrees of freedom 
# Null hypothesis probability =   1.273736e-01
 
Photon flux (15-150 keV)    in 135.4 sec: 9.93491E-02 ( -0.0190995  0.0191299 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.08806e-07 ( -1.45585e-07  1.57141e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from  -71.096 sec. to   64.264 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.785268     (       )
Epeak [keV] : 17.0778      (   )
Norm@50keV  : 1.16524E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.93 using 59 PHA bins.
# Reduced chi-squared =          1.195 for     56 degrees of freedom 
# Null hypothesis probability =   1.504501e-01
 
Photon flux (15-150 keV)    in 135.4 sec: 9.64125E-02 ( -0.0185387  0.0187295 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.19353e-07 ( -1.52975e-07  1.48482e-07 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from   49.396 sec. to   50.396 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.62682     ( -0.703711   0.705801 )
Norm@50keV  : 4.17882E-03    ( -0.00169881   0.00164149 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.65 using 59 PHA bins.
# Reduced chi-squared =         0.6956 for     57 degrees of freedom 
# Null hypothesis probability =   9.610825e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.541574 ( -0.211634  0.213258 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.89646e-08 ( -1.60881e-08  1.66348e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   49.396 sec. to   50.396 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.62502     ( -1.15488   4.3006 )
Epeak [keV] : 9998.44      ( -9999.12 -9999.12 )
Norm@50keV  : 4.18820E-03    ( -0.00418815   -0.00418815 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.65 using 59 PHA bins.
# Reduced chi-squared =         0.7080 for     56 degrees of freedom 
# Null hypothesis probability =   9.518677e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.541133 ( -0.209966  0.21285 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.90697e-08 ( -2.32805e-08  1.43584e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 130.432 sec.
Hardness ratio (energy fluence ratio) = 0.546021924106

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

S(15-50 keV)  = 4.57263e-07
S(50-150 keV) = 1.5154834e-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 = 0.650030747167,

Spacecraft aspect plot

Bright

Pre-burst

 Time interval of the image: -466.799400 -444.850000 -239.000000 -71.096000

# RAcent #  [deg] 255.9963 -37.7498 256.3772 -36.5025 263.0181 -24.6199 264.8677 -44.6346 268.3373  -1.5834 270.4893 -24.9757 270.2967 -25.7671 274.0758 -14.0652 275.9392 -30.5105 285.0403 -25.0665 288.8419  10.9101 262.7898 -33.9130 355.0044 -37.1182 302.2495   0.6924 296.3931   0.9420 122.4424 -82.0720

Pre-slew

 Time interval of the image: -71.096000 64.264000

# RAcent #  [deg] 255.9969 -37.8435 256.3351 -36.5203 262.9056 -24.5947 264.8677 -44.3889 268.3004  -1.5371 270.3805 -24.9720 270.2614 -25.8721 273.8945 -14.0714 275.8462 -30.3856 285.0096 -24.7735 288.8432  10.9855 262.8993 -33.8403 35.2890 -71.4105 95.0289 -82.8657 278.9352 -12.0203

Post-slew

 Time interval of the image: -547.000000 -444.850000 -239.000000 357.760400 361.000000 963.085300

# RAcent #  [deg] 255.9252 -37.8221 256.4009 -36.4932 262.9976 -24.6147 264.8404 -44.5898 268.2564  -1.5023 270.2672 -25.0943 270.3025 -25.7434 274.0018 -14.0248 275.9366 -30.2857 285.2019 -24.8664 288.8093  10.9236 262.7597 -33.9043 355.0178 -37.0981 300.7360  12.1937 277.3852 -23.8389

IMY = 0.437727146852 source in the pre-burst/pre-slew/post-slew images

image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 57.9 34.8 -90.6 0.0705 0.2 5.7 4U 1700-377 5.8 35.1 -88.5 0.7271 2.0 5.5 GX 349+2 5.0 37.3 -66.3 0.7654 2.3 7.6 GX 1+4 0.0 26.2 -99.0 0.3323 1.5 12.3 4U 1735-44 4.3 52.2 -40.0 -2.1072 -2.7 8.1 SW J1753.5-0127 0.0 32.1 -58.5 -0.3048 -1.3 12.8 GX 5-1 5.7 31.7 -59.8 0.4692 2.0 1.5 GRS 1758-258 3.2 38.6 -42.2 0.9483 3.6 4.4 GX 17+2 8.2 24.8 -59.9 0.2776 1.4 8.6 H1820-303 174.9 23.8 -36.3 -0.0113 -0.1 8.8 HT1900.1-2455 4.6 56.7 -11.0 1.7445 2.5 3.3 GRS 1915+105 6.1 31.8 -79.7 0.5181 1.9 11.0 GX 354-0 2.7 40.1 102.8 3.4425 4.2 ------ UNKNOWN 2.3 45.2 4.8 1.5590 5.0 ------ UNKNOWN 2.5 45.8 -3.4 1.4905 4.5 ------ UNKNOWN 2.7 53.4 -175.5 2.0882 4.3 ------ UNKNOWN background subtracted image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 975.4 34.8 -90.8 -0.0038 -0.0 0.5 4U 1700-377 391.8 35.1 -88.5 0.0098 0.0 7.6 GX 349+2 0.0 37.4 -66.4 -0.6858 -2.1 10.7 GX 1+4 3.5 26.3 -98.4 0.6821 3.3 6.5 4U 1735-44 3.6 52.3 -40.0 2.4759 3.2 6.5 SW J1753.5-0127 12.6 32.2 -58.7 0.2187 0.9 8.3 GX 5-1 8.7 31.6 -60.0 0.3027 1.3 8.1 GRS 1758-258 5.8 38.7 -42.5 0.5300 2.0 6.8 GX 17+2 4.4 24.9 -59.8 0.5148 2.6 4.2 H1820-303 13.3 24.1 -36.0 0.1423 0.9 8.9 HT1900.1-2455 39.3 56.8 -11.0 -0.2037 -0.3 3.6 GRS 1915+105 5.4 31.8 -79.5 -0.5558 -2.2 4.5 GX 354-0 2.0 49.3 159.6 2.9453 5.8 ------ UNKNOWN 2.2 51.9 -179.6 2.2327 5.3 ------ UNKNOWN 1.9 38.1 -34.0 1.4459 6.1 ------ UNKNOWN image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 4.9 34.8 -90.8 3.5493 2.4 3.2 4U 1700-377 4.5 35.1 -88.4 4.1494 2.6 4.5 GX 349+2 5.8 37.3 -66.4 3.1613 2.0 7.9 GX 1+4 4.3 26.2 -98.9 2.4142 2.7 9.4 4U 1735-44 6.2 52.4 -40.1 5.5210 1.9 7.3 SW J1753.5-0127 123.8 32.2 -59.0 0.0842 0.1 1.3 GX 5-1 4.9 31.7 -59.8 2.0560 2.4 0.0 GRS 1758-258 2.0 38.7 -42.3 6.3553 5.7 0.7 GX 17+2 11.8 25.0 -59.5 0.7785 1.0 4.9 H1820-303 41.1 23.9 -35.8 -0.2073 -0.3 9.6 HT1900.1-2455 3.5 56.8 -11.1 10.0637 3.3 1.5 GRS 1915+105 0.0 31.8 -79.7 1.9674 1.7 12.2 GX 354-0 4.0 40.1 102.8 11.6530 2.9 ------ UNKNOWN 4.9 56.8 3.0 10.0266 2.4 ------ UNKNOWN 1.8 28.8 -47.7 5.2505 6.5 ------ UNKNOWN

Analysis Summary

Notes:

Image

Pre-slew 15.0-50.0 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

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