GRB181213A: 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 Mar 17 23:16:25 EDT 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger876016
======================================================================

  Trigger: 00876016      Segment: 000

  BAT Trigger Time: 566398680.512   [s; MET]
      Trigger Stop: 566398696.896   [s; MET]
               UTC: 2018-12-13T12:57:38.436940    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 248.207112628901   Dec: 78.5044118700811  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    11.3
     Image Trigger?:     NO
     Rate S/N Ratio:     13.7840487520902  [ if not an image trigger ]
     Image S/N Ratio:    11.3

  Analysis Position:   [ source = BAT ]
    RA: 248.207112628901   Dec: 78.5044118700811  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 248.209012269858   Dec: 78.5009395453647  [deg; J2000]  
        { 16h 32m 50.2s , +78d 30' 03.4" }
         +/- 1.91872039564987 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.814314192779804 [arcmin] (formal 1-sigma fit error)
    SNR: 11.9899110935762
 
  Angular difference between the analysis and refined position is 0.209574 arcmin
 
  Partial Coding Fraction: 0.2128906    [ including projection effects ]

  Duration
     T90: 15.2960000038147 +/- 1.38101413587535
        Measured from: 0.136000037193298
                   to: 15.432000041008     [s; relative to TRIGTIME]
     T50: 11.1520000696182 +/- 2.29403404597699
        Measured from: 2.1360000371933
                   to: 13.2880001068115     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.16400003433228     
                   to: 2.16400003433228     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.407999992370605     
                   to: 15.944000005722     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.496868   0.829836   0.576293   0.163402
           0.077810   0.081559   0.075385   0.066920 [error]
 Peak      0.074057   0.093693   0.052313   0.040305
           0.019198   0.021849   0.021214   0.016333 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   16.352   -0.408   15.944
T90    15.296    0.136   15.432
T50    11.152    2.136   13.288
Peak    1.000    1.164    2.164
 
 
====== 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      -1.583    -0.200      0.197       -           -               -         9.41e-03     -1.09e-03          1.08e-03      39.300   57
CPL     -1.496    -1.326      0.824      270.472    -270.472      -270.472      1.04e-02     -8.54e-03          1.65e-02      39.280   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      -1.697     -0.455     0.420       -           -               -         1.57e-02     -4.63e-03          4.51e-03      47.380   57
CPL     -0.650     -1.549     2.986       60.959     -28.982       -60.959      5.74e-02     -5.74e-02          2.34e+00      46.440   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   2.12e-07  3.71e-07  4.95e-07  1.35e-06  1.44e-06  2.43e-06   erg/cm2
      90%_error_low -4.00e-08 -4.41e-08 -7.45e-08 -3.89e-07 -1.78e-07 -4.56e-07   erg/cm2
      90%_error_hi   4.20e-08  4.37e-08  7.38e-08  4.80e-07  1.80e-07  5.27e-07   erg/cm2
Peak flux       PL   7.81e-01  7.00e-01  4.32e-01  4.05e-01  2.08e+00  2.32e+00   ph/cm2/s
      90%_error_low -3.03e-01 -1.95e-01 -1.56e-01 -2.25e-01 -5.73e-01 -6.33e-01   ph/cm2/s
      90%_error_hi   3.30e-01  1.94e-01  1.53e-01  3.26e-01  5.74e-01  6.35e-01   ph/cm2/s
 
Fluence        CPL   2.10e-07  3.74e-07  4.98e-07  1.19e-06  1.43e-06  2.27e-06   erg/cm2
      90%_error_low -4.67e-08 -4.72e-08 -7.68e-08 -8.02e-07 -1.95e-07 -8.25e-07   erg/cm2
      90%_error_hi   3.98e-08  5.48e-08  8.03e-08  2.53e-07  1.86e-07  6.59e-07   erg/cm2
Peak flux      CPL   6.82e-01  7.95e-01  4.68e-01  1.47e-01  2.05e+00  2.09e+00   ph/cm2/s
      90%_error_low -3.56e-01 -2.53e-01     N/A   -1.47e-01 -5.79e-01 -6.09e-01   ph/cm2/s
      90%_error_hi   3.73e-01  2.84e-01     N/A    3.68e-01  5.78e-01  3.59e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  248.2090    78.5009   0.0160    47.5642  -148.1640         1.9556417     11.990 TRIG_00876016                 
 
Foreground time interval of the image:
 -0.408  15.944 (delta_t =  16.352 [sec])
Background time interval of the image:
-696.311 -680.381 (delta_t =  15.930 [sec])
-239.512  -0.408 (delta_t = 239.104 [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   -0.408 sec. to   15.944 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.58252     ( -0.199716   0.197261 )
Norm@50keV  : 9.40880E-03    ( -0.00109224   0.00108504 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.30 using 59 PHA bins.
# Reduced chi-squared =         0.6895 for     57 degrees of freedom 
# Null hypothesis probability =   9.644334e-01
 
Photon flux (15-150 keV)    in 16.35 sec: 1.20266 ( -0.14023  0.14071 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.44201e-06 ( -1.78297e-07  1.79682e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.408 sec. to   15.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.49606     ( -1.32341   0.82732 )
Epeak [keV] : 270.472      ( -306.638 -306.638 )
Norm@50keV  : 1.04210E-02    ( -0.00845883   0.0166258 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.28 using 59 PHA bins.
# Reduced chi-squared =         0.7014 for     56 degrees of freedom 
# Null hypothesis probability =   9.560926e-01
 
Photon flux (15-150 keV)    in 16.35 sec: 1.19881 ( -0.14457  0.14319 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.43406e-06 ( -1.95356e-07  1.85576e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.164 sec. to    2.164 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.69712     ( -0.455146   0.419594 )
Norm@50keV  : 1.57030E-02    ( -0.00462664   0.00450963 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.38 using 59 PHA bins.
# Reduced chi-squared =         0.8312 for     57 degrees of freedom 
# Null hypothesis probability =   8.143289e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.08353 ( -0.57334  0.5743 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.45445e-07 ( -4.36163e-08  4.43435e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.164 sec. to    2.164 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.650172     ( -1.54929   2.98618 )
Epeak [keV] : 60.9586      ( -28.9813 -60.9576 )
Norm@50keV  : 5.73653E-02    ( -0.0573691   2.33968 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.44 using 59 PHA bins.
# Reduced chi-squared =         0.8292 for     56 degrees of freedom 
# Null hypothesis probability =   8.151271e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.05298 ( -0.57914  0.57832 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.38663e-07 ( -4.55158e-08  4.65963e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 15.296 sec.
Hardness ratio (energy fluence ratio) = 1.33561124135

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

S(15-50 keV)  = 5.831166e-07
S(50-150 keV) = 8.589202e-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 = -9.292220457320508E-01, IMY = 5.769502027173130E-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:
-696.311400 -680.381100
-239.512000 -0.408000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 44.5527  71.7084    3.0  47.2  171.8   2.7098   3.8 ------	UNKNOWN                       
166.1027  10.2831    3.0  43.4  -23.5   1.8495   3.8 ------	UNKNOWN                       
174.8589   2.7522    2.8  54.2  -29.0   4.3101   4.1 ------	UNKNOWN                       
180.8857  13.2134    2.4  48.7  -42.8   4.8088   4.8 ------	UNKNOWN                       

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

Time interval of the image:
-0.408000 15.944000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
248.2092  78.5009    1.0  47.6 -148.2   1.9561  12.0 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
213.988600 654.794800
660.488000 719.368000
720.488000 900.588600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.2236 -60.4213    7.7  28.7   36.4   1.2132   1.5   12.4	Cen X-3                       
186.6769 -62.7724    0.9  23.9   21.4   9.7179  12.7    0.6	GX 301-2                      
244.9636 -15.6656    1.1  42.3 -117.5  22.5225  10.7    1.8	Sco X-1                       
256.0104 -37.8446    3.6  37.8  -80.0   5.4765   3.2    1.1	4U 1700-377                   
256.6074 -36.3637    5.1  38.9  -81.9   4.3685   2.2    9.0	GX 349+2                      
264.6316 -44.3613   14.6  41.8  -67.0   1.9073   0.8    7.1	4U 1735-44                    
132.9626 -59.8446    5.0  46.8   40.4   5.3623   2.3 ------	UNKNOWN                       
174.0616 -27.4050    4.0  29.9  107.5   3.0384   2.9 ------	UNKNOWN                       
323.8081 -74.2227    3.7  56.7  -17.7   7.9854   3.1 ------	UNKNOWN                       
225.6909  12.8515    2.4  57.5 -158.4  18.5019   4.8 ------	UNKNOWN