GRB191227A: 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 v2.47
    Process Start Time: Mon May 18 15:12:11 EDT 2020
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger946344
======================================================================

  Trigger: 00946344      Segment: 000

  BAT Trigger Time: 599103601.728   [s; MET]
      Trigger Stop: 599103602.752   [s; MET]
               UTC: 2019-12-27T01:39:37.570780    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 319.169545066939   Dec: -16.7044309198896  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    16.65
     Image Trigger?:     NO
     Rate S/N Ratio:     76.4983659956211  [ if not an image trigger ]
     Image S/N Ratio:    16.65

  Analysis Position:   [ source = BAT ]
    RA: 319.169545066939   Dec: -16.7044309198896  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 319.168468132108   Dec: -16.7173546059946  [deg; J2000]  
        { 21h 16m 40.4s , -16d 43' 02.5" }
         +/- 1.04820960164387 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.439549872494594 [arcmin] (formal 1-sigma fit error)
    SNR: 28.4385049122436
 
  Angular difference between the analysis and refined position is 0.777887 arcmin
 
  Partial Coding Fraction: 0.1328125    [ including projection effects ]

  Duration
     T90: 55.8880000114441 +/- 16.2818455193879
        Measured from: -13.9680000543594
                   to: 41.9199999570847     [s; relative to TRIGTIME]
     T50: 9.79200005531311 +/- 0.633567611205587
        Measured from: 1.43999993801117
                   to: 11.2319999933243     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 5.26800000667572     
                   to: 6.26800000667572     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -30.5600000619888     
                   to: 105.919999957085     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     6.637621  11.318507  11.038217   4.620650
           0.265075   0.289166   0.274289   0.241850 [error]
 Peak      0.440665   0.814858   0.965302   0.405716
           0.037224   0.047258   0.051948   0.041250 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  136.480  -30.560  105.920
T90    55.888  -13.968   41.920
T50     9.792    1.440   11.232
Peak    1.000    5.268    6.268
 
 
====== 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      -1.293    -0.052      0.053       -           -               -         1.84e-02     -5.28e-04          5.27e-04      51.160   57
CPL     -1.244    -0.078      0.144      918.030    -918.030      -918.030      1.93e-02     -1.36e-03          2.54e-03      51.490   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      -1.110     -0.100     0.100       -           -               -         1.86e-01     -1.10e-02          1.10e-02      65.520   57
CPL     -0.823     -0.327     0.402      245.673      N/A           N/A         2.48e-01        N/A               N/A         63.780   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   2.64e-06  5.51e-06  8.99e-06  3.30e-05  2.48e-05  5.02e-05   erg/cm2
      90%_error_low -1.61e-07 -1.99e-07 -2.81e-07 -2.38e-06 -7.18e-07 -2.49e-06   erg/cm2
      90%_error_hi   1.65e-07  1.98e-07  2.81e-07  2.50e-06  7.20e-07  2.59e-06   erg/cm2
Peak flux       PL   5.28e+00  6.70e+00  6.21e+00  1.01e+01  2.16e+01  2.83e+01   ph/cm2/s
      90%_error_low -6.05e-01 -4.84e-01 -4.05e-01 -1.33e+00 -1.32e+00 -1.76e+00   ph/cm2/s
      90%_error_hi   6.31e-01  4.80e-01  4.02e-01  1.44e+00  1.32e+00  1.78e+00   ph/cm2/s
 
Fluence        CPL   2.65e-06  5.51e-06  8.97e-06  3.36e-05  2.49e-05  5.04e-05   erg/cm2
      90%_error_low -2.28e-07 -2.01e-07 -2.90e-07 -7.44e-06 -8.27e-07 -7.96e-06   erg/cm2
      90%_error_hi   1.79e-07  1.91e-07  3.48e-07  -1.50e-06  6.71e-07  1.21e-06   erg/cm2
Peak flux      CPL   1.59e+00  1.15e+00  5.77e-01  4.99e-01  3.53e+00  4.24e+00   ph/cm2/s
      90%_error_low -1.59e+00 -1.15e+00 -5.77e-01 -4.99e-01 -3.53e+00 -4.24e+00   ph/cm2/s
      90%_error_hi   1.06e+00  7.02e-01  2.94e-01  1.70e-01  2.13e+00  1.75e+00   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  319.1685   -16.7174   0.0068    49.8159  -142.0457        35.1438068     28.439 TRIG_00946344                 
 
Foreground time interval of the image:
-30.560 105.920 (delta_t = 136.480 [sec])
Background time interval of the image:
-239.728 -30.560 (delta_t = 209.168 [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  -30.560 sec. to  105.920 sec.
XSPEC12>exit
 XSPEC: quit
 
 
Photon index: -1.2934     ( -0.0524578   0.0527085 )
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.29340     ( -0.0527085   0.0524578 )
Norm@50keV  : 1.83850E-02    ( -0.000528176   0.000527064 )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in 136.5 sec: 2.19076 ( -0.07008  0.07043 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.48418e-05 ( -7.18142e-07  7.19512e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -30.560 sec. to  105.920 sec.
 XSPEC: quit
 
 
Photon index: -1.28915     ( -0.0777583   0.144849 )
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.28915     ( -0.144849   0.0777583 )
Epeak [keV] : 9998.31      ( -9998.38 -9998.38 )
Norm@50keV  : 1.84627E-02    ( -0.000522235   0.00338196 )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in 136.5 sec: 0.916918 ( -0.10306  0.060564 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.48618e-05 ( -8.27473e-07  6.70623e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    5.268 sec. to    6.268 sec.
XSPEC12>exit
 XSPEC: quit
 
 
Photon index: -1.10965     ( -0.0998047   0.100249 )
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.10965     ( -0.100249   0.0998047 )
Norm@50keV  : 0.186171    ( -0.0110109   0.0109966 )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in 1 sec: 21.6153 ( -1.3184  1.3199 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.94071e-06 ( -1.23647e-07  1.24004e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    5.268 sec. to    6.268 sec.
 XSPEC: quit
 
 
Photon index: -0.823392     ( -0.327101   0.402445 )
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.823392     ( -0.402445   0.327101 )
Epeak [keV] : 245.673      (   )
Norm@50keV  : 0.247881    (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in 1 sec: 3.52759 ( -3.52759  2.13326 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.93015e-06 ( -1.26136e-07  1.2593e-07 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 55.888 sec.
Hardness ratio (energy fluence ratio) = 1.63196202256

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

S(15-50 keV)  = 8.150014e-06
S(50-150 keV) = 1.6692046e-05

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 = -9.335905422901772E-01, IMY = 7.282031051986453E-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:
-239.728000 -30.560000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.2741  35.3734    4.1  32.6   14.6  -0.9308  -2.8    9.2	Her X-1                       
268.2531  -1.5739   34.3  33.0  -61.8   0.1373   0.3   10.0	SW J1753.5-0127               
273.9045 -13.9653    8.1  41.0  -80.2   1.6293   1.4    7.3	GX 17+2                       
288.7646  10.7993    4.8  13.2  -99.8   0.6072   2.4    9.0	GRS 1915+105                  
299.6424  35.2648    4.6  14.2  110.9   0.7279   2.5    4.6	Cyg X-1                       
308.0983  41.0498    3.0  22.9  113.5   1.3355   3.9    5.9	Cyg X-3                       
326.0838  38.1989   12.2  33.9  132.5  -0.4277  -0.9    8.5	Cyg X-2                       
253.2206  18.4767    2.8  34.4  -16.1   1.2422   4.1 ------	UNKNOWN                       
237.0735  12.8807    2.6  50.9  -16.8   2.4853   4.4 ------	UNKNOWN                       
239.3877  -0.2315    2.9  54.5  -32.9   4.8036   3.9 ------	UNKNOWN                       
313.3881 -20.2154    3.1  49.8 -133.5   4.7396   3.7 ------	UNKNOWN                       
281.5228 -16.0193    2.7  40.8  -91.9   5.0188   4.3 ------	UNKNOWN                       
286.0056 -16.9618    3.3  41.1  -98.6   3.6883   3.6 ------	UNKNOWN                       
309.2430 -20.0871    3.0  48.0 -129.0   4.1485   3.8 ------	UNKNOWN                       

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

Time interval of the image:
-30.560000 105.920000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3441  35.2031    6.0  32.6   14.3   0.5740   1.9   10.0	Her X-1                       
268.4877  -1.4925   10.0  32.8  -62.0  -0.5687  -1.2    7.6	SW J1753.5-0127               
273.9067 -14.1308   10.7  41.1  -80.3   1.7641   1.1    8.1	GX 17+2                       
288.9474  10.9358    5.3  13.1 -100.5   0.5590   2.2    8.8	GRS 1915+105                  
299.5865  35.2050   33.2  14.1  110.9  -0.0892  -0.3    0.3	Cyg X-1                       
308.1599  40.7700    4.0  22.8  114.1   0.7886   2.9   11.2	Cyg X-3                       
326.0263  38.2350    5.2  33.9  132.4   0.8367   2.2    8.6	Cyg X-2                       
229.5704  34.0049    3.3  52.8   11.5   3.5916   3.6 ------	UNKNOWN                       
306.5299  20.8030    3.0  15.8  174.3   0.9529   3.9 ------	UNKNOWN                       
319.1685 -16.7174    0.4  49.8 -142.0  35.1425  28.4 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
423.772600 962.322000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 66.0841  15.5464    3.7  37.8  120.7   4.6536   3.1 ------	UNKNOWN                       
 65.0310  31.6174    2.7  25.9   99.9   3.4338   4.2 ------	UNKNOWN                       
189.2179  81.3149    2.9  54.9   -1.8   8.0934   4.0 ------	UNKNOWN                       
325.9618  53.5262    3.5  45.6  -57.7   7.8254   3.3 ------	UNKNOWN                       
356.1887   9.4395    2.7  48.0 -129.0   9.1013   4.3 ------	UNKNOWN