batgrbproduct analysis for trigger=883818

batgrbproduct Analysis for Trigger=883818

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 (local time): Sun Mar 17 22:45:22 EDT 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger883818
======================================================================

  Trigger: 00883818      Segment: 000

  BAT Trigger Time: 569187094.336   [s; MET]
      Trigger Stop: 569187110.72   [s; MET]
               UTC: 2019-01-14T19:31:12.086340    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 174.882937593776   Dec: 18.8766590141854  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.12
     Image Trigger?:     NO
     Rate S/N Ratio:     9.48683298050514  [ if not an image trigger ]
     Image S/N Ratio:    7.12

  Flight Position:   [ source = BAT ]
    RA: 174.882937593776   Dec: 18.8766590141854  [deg; J2000]

  Ground Position:   [ source = BAT pre-slew burst ]
    RA: 174.86793074047   Dec: 18.8814949319361  [deg; J2000]  
        { 11h 39m 28.3s , +18d 52' 53.4" }
         +/- 2.2922620327574 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.20712298966811 [arcmin] (formal 1-sigma fit error)
    SNR: 9.29940473488376
 
  Angular difference between Flight and Ground position is 0.900026 arcmin
 
  Partial Coding Fraction: 0.6328125    [ including projection effects ]

  Duration
     T90: 26.4919999837875 +/- 6.69042210499976
        Measured from: 0.167999982833862
                   to: 26.6599999666214     [s; relative to TRIGTIME]
     T50: 13.0479999780655 +/- 4.12861484108176
        Measured from: 4.44400000572205
                   to: 17.4919999837875     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 3.62400007247925     
                   to: 4.62400007247925     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.16399991512299     
                   to: 27.8999999761581     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.309884   0.423022   0.143154   0.045916
           0.046547   0.049057   0.044696   0.043927 [error]
 Peak      0.028981   0.013750   0.017731   0.025360
           0.008819   0.009573   0.008593   0.008429 [error]

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

======================================================================
 
=== 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   Power-law 1.11e-07 1.53e-07 1.56e-07 2.88e-07 5.11e-07 7.09e-07   erg/cm2
              Error 2.28e-08 2.33e-08 4.15e-08 1.51e-07 9.59e-08 1.98e-07   erg/cm2
Peak flux Power-law 2.38e-01 1.78e-01 8.88e-02 6.31e-02 5.35e-01 5.69e-01   ph/cm2/s
              Error 1.99e-01 8.27e-02 8.35e-02 1.31e-01 2.31e-01 2.55e-01   ph/cm2/s
 
Fluence   Cutoff-PL 1.08e-07 1.66e-07 1.43e-07 8.02e-08 4.68e-07 5.00e-07   erg/cm2
              Error 2.45e-08 4.40e-08 6.47e-08 1.60e-07 1.26e-07 2.53e-07   erg/cm2
Peak flux Cutoff-PL 2.13e-01 1.56e-01 7.87e-02 6.68e-02 4.76e-01 5.14e-01   ph/cm2/s
              Error -------- 1.26e-01 6.53e-02 5.12e-02 3.81e-01 --------   ph/cm2/s
 
Fluence        Band -------- -------- -------- -------- -------- --------   erg/cm2
              Error -------- -------- -------- -------- -------- --------   erg/cm2
Peak flux      Band -------- -------- -------- -------- -------- --------   ph/cm2/s
              Error -------- -------- -------- -------- -------- --------   ph/cm2/s

 
=== Time-averaged spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    1.977    0.283    -      -           1.91e-03 3.73e-04   54.720 57
CPL   1.324    1.756      39.2   -1.5      4.83e-03 1.34e-01   54.120 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    2.004    1.199    -      -           3.56e-03 2.82e-03   60.730 57
CPL   2.106    1.503      44.5    0.0      2.76e-03 0.00e+00   60.460 56
 
Model      : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index   : photon index: E^-{Ph_index} (minus sign is not included in the 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 PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2       : Chi-Squared
dof        : degree of freedom

 
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
 
T90 in the 50-300 keV band: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100   29.064   -1.164   27.900
T90    26.492    0.168   26.660
T50    13.048    4.444   17.492
Peak    1.000    3.624    4.624

Click here for the BAT GCN circular template

Special notes of this burst

Estimated redshift from machine learning (Ukwatta et al. 2016) - may take a few minute to calcaulte

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  174.8679    18.8815   0.0207    35.8443     2.3629         0.9408097      9.299 TRIG_00883818                 
 
Foreground time interval of the image:
 -1.164  27.900 (delta_t =  29.064 [sec])
Background time interval of the image:
-239.336  -1.164 (delta_t = 238.172 [sec])

Lightcurves

Notes:

1) The mask-weighted light curves are using the flight position.
2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
5) Time of each bin is in the middle of the bin.

1 s binning

From T0-310 s to T0+310 s

From T100_start - 20 s to T100_end + 30 s

Full time interval

64 ms binning

Full time interval

From T100_start to T100_end

From T0-5 sec to T0+5 sec

16 ms binning

From T100_start-5 s to T100_start+5 s

8 ms binning

From T100_start-3 s to T100_start+3 s

2 ms binning

From T100_start-1 s to T100_start+1 s

SN=5 or 10 sec. binning (whichever binning is satisfied first)

SN=5 or 10 sec. binning (T < 200 sec)

Quad-rate summed light curves (from T0-300s to T0+1000s)

Spectral Evolution

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   -1.164 sec. to   27.900 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.97693     ( -0.272865   0.293731 )
Norm@50keV  : 1.91405E-03    ( -0.00037894   0.000367713 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.72 using 59 PHA bins.
# Reduced chi-squared =         0.9599 for     57 degrees of freedom 
# Null hypothesis probability =   5.612851e-01
 
Photon flux (15-150 keV)    in 29.06 sec: 0.284124 ( -0.042406  0.042407 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.12467e-07 ( -9.42178e-08  9.76393e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -1.164 sec. to   27.900 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.32448     ( -2.69269   0.818616 )
Epeak [keV] : 39.2310      ( -36.1731 -39.1694 )
Norm@50keV  : 4.83357E-03    ( -0.00491556   0.263807 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.12 using 59 PHA bins.
# Reduced chi-squared =         0.9664 for     56 degrees of freedom 
# Null hypothesis probability =   5.464953e-01
 
Photon flux (15-150 keV)    in 29.06 sec: 0.277288 ( -0.046203  0.045038 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.67041e-07 ( -1.24781e-07  1.26644e-07 ) ergs/cm2

Band function

Time interval is from   -1.164 sec. to   27.900 sec.
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

Single BB

 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 8.83387  (-1.28067  1.54299)
R^2/D10^2   : 0.216824  (-0.101554   0.183079)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.24 using 59 PHA bins.
# Reduced chi-squared =          1.004 for     57 degrees of freedom 
# Null hypothesis probability =   4.660455e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  9.479e-08   2.381e-08
25- 50  1.956e-07   4.738e-08
50-150  7.047e-08   3.044e-08
15-150  3.609e-07   8.023e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 61.7582       (-22.9818      49.8641)
Norm        : 1.47487       (-0.335659     0.449011)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.06 using 59 PHA bins.
# Reduced chi-squared =         0.9485 for     57 degrees of freedom 
# Null hypothesis probability =   5.859981e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.082e-07   2.100e-08
25- 50  1.661e-07   3.271e-08
50-150  1.936e-07   8.377e-08
15-150  4.679e-07   1.096e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 7.66453        (-1.38522      1.68159)
R1^2/D10^2  : 0.340959        (-0.161694      0.387606)
kT2 [keV]   : 55.7694        (-51.7863      -72.5108)
R2^2/D10^2  : 2.27081E-04    (-0.000121771   0.00396684)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.80 using 59 PHA bins.
# Reduced chi-squared =         0.9055 for     55 degrees of freedom 
# Null hypothesis probability =   6.729472e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.038e-07   3.861e-08
25- 50  1.803e-07   6.985e-08
50-150  2.431e-07   1.381e-07
15-150  5.272e-07   1.864e-07

Peak spectrum fit

Power-law model

Time interval is from    3.624 sec. to    4.624 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.00433     ( -1.03696   1.3614 )
Norm@50keV  : 3.55813E-03    ( -0.00355692   0.00208544 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.73 using 59 PHA bins.
# Reduced chi-squared =          1.065 for     57 degrees of freedom 
# Null hypothesis probability =   3.431013e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.534821 ( -0.231008  0.23098 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.28148e-08 ( -1.82095e-08  2.05457e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    3.624 sec. to    4.624 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.10573     ( -2.10575   0.900979 )
Epeak [keV] : 44.4878      (   )
Norm@50keV  : 2.75659E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.46 using 59 PHA bins.
# Reduced chi-squared =          1.080 for     56 degrees of freedom 
# Null hypothesis probability =   3.178922e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.475655 ( -0.475655  0.28638 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

Band function

Time interval is from    3.624 sec. to    4.624 sec.
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

Single BB

 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 5.93491  (-2.24917  4.25007)
R^2/D10^2   : 1.88348  (-1.88348   13.9162)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.44 using 59 PHA bins.
# Reduced chi-squared =          1.095 for     57 degrees of freedom 
# Null hypothesis probability =   2.891786e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.676e-09   5.495e-09
25- 50  8.448e-09   5.705e-09
50-150  7.397e-10   7.190e-10
15-150  1.787e-08   1.184e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 72.7090       (-75.8231      -75.8231)
Norm        : 2.50652       (-1.29552     11.4664)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.76 using 59 PHA bins.
# Reduced chi-squared =          1.084 for     57 degrees of freedom 
# Null hypothesis probability =   3.099257e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  6.455e-09   4.471e-09
25- 50  1.037e-08   6.770e-09
50-150  1.370e-08   1.310e-08
15-150  3.053e-08   2.244e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 5.35665        (-2.18124      1.96621)
R1^2/D10^2  : 2.68260        (-2.27494      25.6449)
kT2 [keV]   : 84.8824        (-161.042      -183.027)
R2^2/D10^2  : 3.67566E-04    (-8.38342e-05   0.0102177)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.48 using 59 PHA bins.
# Reduced chi-squared =          1.045 for     55 degrees of freedom 
# Null hypothesis probability =   3.834173e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.714e-09   5.515e-09
25- 50  8.051e-09   5.085e-09
50-150  2.704e-08   1.540e-08
15-150  4.380e-08   2.382e-08

Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)

Power-law model

 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.97693     ( -0.272865   0.293731 )
Norm@50keV  : 1.91405E-03    ( -0.00037894   0.000367713 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.72 using 59 PHA bins.
# Reduced chi-squared =         0.9599 for     57 degrees of freedom 
# Null hypothesis probability =   5.612851e-01
 
Photon flux (15-150 keV)    in 29.06 sec: 0.284104 ( -0.0424034  0.0424035 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.12377e-07 ( -9.41285e-08  9.76788e-08 ) ergs/cm2

Cutoff power-law model

Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.32666     ( -2.69413   0.817242 )
Epeak [keV] : 39.2459      (   )
Norm@50keV  : 4.81791E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.12 using 59 PHA bins.
# Reduced chi-squared =         0.9664 for     56 degrees of freedom 
# Null hypothesis probability =   5.464997e-01
 
Photon flux (15-150 keV)    in 29.06 sec: 0.277153 ( -0.046133  0.045091 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.67049e-07 ( -1.24897e-07  1.31188e-07 ) ergs/cm2

Band function

 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

S(25-50 keV) vs. S(50-100 keV) plot

S(25-50 keV)  = 1.53e-07
S(50-100 keV) = 1.56e-07

T90 vs. Hardness ratio plot

T90                                   = 26.4919999837875 sec.
Hardness ratio (energy fluence ratio) = 1.01961

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.3651
Count Ratio (50-100 keV) / (15-25 keV) = 0.46196

Mask shadow pattern

IMX = 7.217858374019105E-01, IMY = -2.978403258128292E-02

TIME vs. PHA plot around the trigger time

TIME vs. DetID plot around the trigger time

100 us light curve (15-350 keV)

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:
-239.336000 -1.164000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 41.0282  61.3932    2.5  55.9 -178.3   5.1531   4.5 ------	UNKNOWN                       
174.0115  32.8705    2.9  22.7   -8.0   0.9473   4.0 ------	UNKNOWN                       
180.6633  32.6107    2.4  26.0  -19.1   1.2548   4.7 ------	UNKNOWN

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

Time interval of the image:
-1.164000 27.900000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
174.8681  18.8814    1.2  35.8    2.4   0.9520   9.4 ------	UNKNOWN                       
131.3818  68.8508    2.2  20.9 -172.0   0.3915   5.3 ------	UNKNOWN                       
181.6292  14.3285    2.1  42.5   -4.6   0.6392   5.4 ------	UNKNOWN                       
148.7744  69.5958    2.3  18.3 -155.2   0.3558   5.0 ------	UNKNOWN                       
187.6714  11.7017    1.9  47.3  -10.6   0.7837   6.1 ------	UNKNOWN                       
181.3797  51.6652    2.4  15.5  -66.8   0.3612   4.8 ------	UNKNOWN                       
 27.3035  64.0473    2.3  57.7 -170.5   2.0904   5.0 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
141.164620 962.714000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
144.1040  -3.4900    3.1  37.7   43.7   4.4730   3.7 ------	UNKNOWN                       
235.2149  52.5725    3.9  57.2 -154.1  14.8196   3.0 ------	UNKNOWN

Plot creation:
Thu Mar 21 14:26:18 EDT 2019