GRB151001B: 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: Sun Nov  1 01:30:34 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger657321
======================================================================

  Trigger: 00657321      Segment: 000

  BAT Trigger Time: 465416992   [s; MET]
      Trigger Stop: 465417056   [s; MET]
               UTC: 2015-10-01T18:29:36.787760    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 336.844828924081   Dec: 64.6607919699014  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.4
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    7.4

  Analysis Position:   [ source = BAT ]
    RA: 336.844828924081   Dec: 64.6607919699014  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 336.959072323374   Dec: 64.6468660404292  [deg; J2000]  
        { 22h 27m 50.2s , +64d 38' 48.7" }
         +/- 2.13371853446056 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.15428672098023 [arcmin] (formal 1-sigma fit error)
    SNR: 10.3020221758911
 
  Angular difference between the analysis and refined position is 3.051005 arcmin
 
  Partial Coding Fraction: 0.2851562    [ including projection effects ]

  Duration
     T90: 131.520000040531 +/- 26.8529220711676
        Measured from: -27.3360000252724
                   to: 104.184000015259     [s; relative to TRIGTIME]
     T50: 63.6000000238419 +/- 18.0376494853698
        Measured from: 10.5680000185966
                   to: 74.1680000424385     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 47.4679999947548     
                   to: 48.4679999947548     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -39.9599999785423     
                   to: 118.680000007153     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.259749   1.122723   0.479636   0.017222
           0.126696   0.130786   0.113448   0.099929 [error]
 Peak      0.021325   0.024169   0.018183   0.028176
           0.010932   0.011765   0.009571   0.008824 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  158.640  -39.960  118.680
T90   131.520  -27.336  104.184
T50    63.600   10.568   74.168
Peak    1.000   47.468   48.468
 
 
====== 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      -2.125    -0.265      0.244       -           -               -         1.07e-03     -1.90e-04          1.84e-04      43.890   57
CPL     -1.958     N/A        N/A          10.454      N/A           N/A         1.34e-03        N/A               N/A         43.880   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      -0.925     -0.842     1.557       -           -               -         4.67e-03     -4.67e-03          -4.17e-03      54.280   57
CPL     -0.967     -0.802     1.617     9999.360    -9999.360      -9999.360      4.76e-03     -4.76e-03          2.02e-02      54.300   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   3.90e-07  4.90e-07  4.50e-07  7.20e-07  1.58e-06  2.05e-06   erg/cm2
      90%_error_low -6.57e-08 -6.39e-08 -1.07e-07 -2.88e-07 -2.44e-07 -4.29e-07   erg/cm2
      90%_error_hi   6.70e-08  6.33e-08  1.11e-07  3.95e-07  2.52e-07  5.11e-07   erg/cm2
Peak flux       PL   1.11e-01  1.57e-01  1.66e-01  3.23e-01  5.36e-01  7.57e-01   ph/cm2/s
      90%_error_low -1.11e-01 -1.57e-01 -7.10e-02 -2.29e-01 -2.81e-01 -3.20e-01   ph/cm2/s
      90%_error_hi   1.55e-01  1.07e-01  6.96e-02  1.84e+00  2.76e-01  4.84e-01   ph/cm2/s
 
Fluence        CPL   3.86e-07  4.96e-07  4.14e-07  5.49e-07  1.57e-06  1.85e-06   erg/cm2
      90%_error_low -5.83e-08 -5.99e-08 -8.60e-08 -3.49e-07 -1.79e-07 -5.47e-07   erg/cm2
      90%_error_hi   5.10e-08  6.47e-08  1.46e-07  6.73e-07  2.20e-07  8.18e-07   erg/cm2
Peak flux      CPL   1.32e-01  1.64e-01  1.59e-01  3.15e-01  5.45e-01  7.91e-01   ph/cm2/s
      90%_error_low -1.32e-01     N/A   -1.59e-01     N/A   -5.45e-01     N/A     ph/cm2/s
      90%_error_hi   1.34e-01     N/A    1.03e-01     N/A    2.71e-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
  336.9591    64.6469   0.0186    33.1457   123.0414         2.8525559     10.302 TRIG_00657321                 
 
Foreground time interval of the image:
-39.960  72.901 (delta_t = 112.861 [sec])
Background time interval of the image:
-239.000 -39.960 (delta_t = 199.040 [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  -39.960 sec. to  118.680 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.12502     ( -0.264833   0.243778 )
Norm@50keV  : 1.06618E-03    ( -0.000190331   0.00018441 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.89 using 59 PHA bins.
# Reduced chi-squared =         0.7700 for     57 degrees of freedom 
# Null hypothesis probability =   8.985070e-01
 
Photon flux (15-150 keV)    in 158.6 sec: 0.169855 ( -0.021201  0.021201 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.57541e-06 ( -2.44455e-07  2.51906e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -39.960 sec. to  118.680 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.98704     (       )
Epeak [keV] : 3.82425      (   )
Norm@50keV  : 1.28636E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.87 using 59 PHA bins.
# Reduced chi-squared =         0.7833 for     56 degrees of freedom 
# Null hypothesis probability =   8.805037e-01
 
Photon flux (15-150 keV)    in 158.6 sec: 0.169620 ( -0.02109  0.021785 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.57037e-06 ( -1.79356e-07  2.20368e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   47.468 sec. to   48.468 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.33886     ( -0.842965   1.5569 )
Norm@50keV  : 8.76267E-05    ( -8.75513e-05   0.000412328 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.89 using 59 PHA bins.
# Reduced chi-squared =         0.9455 for     57 degrees of freedom 
# Null hypothesis probability =   5.923449e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.535520 ( -0.280594  0.27633 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.18681e-08 ( -2.19647e-08  2.19495e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   47.468 sec. to   48.468 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.96675     ( -0.803727   1.61455 )
Epeak [keV] : 9999.36      ( -9999.36 -9999.36 )
Norm@50keV  : 4.75924E-03    ( -0.00475155   0.0202183 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.30 using 59 PHA bins.
# Reduced chi-squared =         0.9697 for     56 degrees of freedom 
# Null hypothesis probability =   5.394280e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.544999 ( -0.544999  0.271267 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.14719e-08 ( -2.15988e-08  2.20082e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 131.52 sec.
Hardness ratio (energy fluence ratio) = 0.917043558509

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

S(15-50 keV)  = 8.801035e-07
S(50-150 keV) = 6.953208e-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 = -3.560606092275742E-01, IMY = -5.474196051367878E-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:
-239.000000 -39.960000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 20.3534  52.3327    2.7  39.6   81.4   3.5403   4.2 ------	UNKNOWN                       
266.6368  56.7551    2.4  41.8  177.7   1.4041   4.8 ------	UNKNOWN                       
169.3313  77.8035    2.8  10.0 -128.7   0.7058   4.2 ------	UNKNOWN                       
241.6932  64.9784    2.9  31.5 -165.0   0.8258   4.0 ------	UNKNOWN                       
228.2063  38.8312    4.1  55.3 -144.7   2.9854   2.8 ------	UNKNOWN                       
217.4469  41.6187    2.5  50.9 -135.4   4.2834   4.6 ------	UNKNOWN                       

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

Time interval of the image:
-39.960000 72.900610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
336.9588  64.6476    1.1  33.1  123.0   2.8541  10.3 ------	UNKNOWN                       
123.7495  44.3292    1.9  36.2  -35.4   1.0883   6.0 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
127.700600 963.080000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.6277  35.1890    2.6  36.9  179.7   3.3893   4.4    2.0	Cyg X-1                       
308.0605  40.9618    1.2  28.9  173.2   6.0445   9.9    2.3	Cyg X-3                       
325.9415  38.2979   45.1  27.2  143.4  -0.1781  -0.3   10.9	Cyg X-2                       
 35.6581  58.6416    2.8  27.5   19.1   2.3197   4.1 ------	UNKNOWN                       
 73.1676  57.6941    5.1  42.4   -3.6   1.8915   2.3 ------	UNKNOWN                       
 98.3938  49.1681    2.4  57.5  -14.2  12.3488   4.7 ------	UNKNOWN                       
268.5579  36.8967    3.1  48.0 -146.4   5.1624   3.7 ------	UNKNOWN                       
111.6378  51.2168    3.7  58.9  -24.3  13.7084   3.1 ------	UNKNOWN                       
262.8606  31.1439    5.0  55.3 -145.1   8.2597   2.3 ------	UNKNOWN                       
250.1128  49.4503    4.1  45.3 -121.4   6.8309   2.8 ------	UNKNOWN