batgrbproduct analysis for trigger=638589

batgrbproduct Analysis for Trigger=638589

Analysis Summary

Notes:

1) No attempt has been made to eliminate the non-significant decimal places.
2) This batgrbproduct analysis is done of the amount of data for this trigger downloaded to date.
3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
4) This page will be updated for up to 10 downlinks after the trigger.

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time (local time): Tue Apr 21 18:36:49 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/prebascript/trigger638589/GCN5_download_cron
======================================================================

  Trigger: 00638589      Segment: 000

  BAT Trigger Time: 451242024   [s; MET]
      Trigger Stop: 451242368   [s; MET]
               UTC: 2015-04-20T17:00:10.527480    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 87.8153793256478   Dec: -10.4224915475194  [deg; J2000]

     Catalogged Source?: YES
     Point Source?:      YES
     GRB Indicated?:     NO    [ by BAT flight software ]
     Image S/N Ratio:    5.81
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    5.81

  Flight Position:   [ source = BAT ]
    RA: 87.8153793256478   Dec: -10.4224915475194  [deg; J2000]

  Ground Position:   [ source = BAT pre-slew burst ]
    RA: 87.8726987649503   Dec: -10.5260531547643  [deg; J2000]  
        { 05h 51m 29.4s , -10d 31' 33.8" }
         +/- 4.95764855849086 [arcmin] (estimated 90% radius based on SNR)
         +/- 2.67149484005019 [arcmin] (formal 1-sigma fit error)
    SNR: 3.08935152128523
 
  Angular difference between Flight and Ground position is 7.074389 arcmin
 
  Partial Coding Fraction: 0.796875    [ including projection effects ]

  Duration
     T90: 416.799999952316 +/- 48.3379910583562
        Measured from: 25.3720000982285
                   to: 442.172000050545     [s; relative to TRIGTIME]
     T50: 187.083999931812 +/- 22.8604140470588
        Measured from: 116.704000115395
                   to: 303.788000047207     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 178.796000003815     
                   to: 179.796000003815     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -13.8640000224113     
                   to: 499.959999978542     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     2.301468   4.407008   1.351704   1.787411
           0.164420   0.185683   0.163947   0.178283 [error]
 Peak      0.020381   0.016151   0.021352   0.019648
           0.007861   0.009141   0.008071   0.009480 [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 8.12e-07 1.33e-06 1.64e-06 4.01e-06 4.91e-06 7.79e-06   erg/cm2
              Error -------- -------- -------- -------- -------- --------   erg/cm2
Peak flux Power-law 1.65e-01 1.70e-01 1.23e-01 1.43e-01 5.13e-01 6.00e-01   ph/cm2/s
              Error 9.92e-02 6.74e-02 6.72e-02 1.82e-01 1.99e-01 2.56e-01   ph/cm2/s
 
Fluence   Cutoff-PL 6.62e-07 1.86e-06 7.48e-07 1.47e-08 3.29e-06 3.29e-06   erg/cm2
              Error -------- -------- -------- -------- -------- --------   erg/cm2
Peak flux Cutoff-PL 1.38e-01 1.90e-01 1.31e-01 4.54e-02 4.92e-01 5.05e-01   ph/cm2/s
              Error 1.32e-01 9.14e-02 7.77e-02 9.17e-02 2.18e-01 2.27e-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    1.694    0.000    -      -           1.04e-03 0.00e+00  156.590 57
CPL  -2.246    0.000      38.4    0.0      2.96e-01 0.00e+00  125.580 56
 
The chi2 of BB fit is 127.88 which shows a significant improvement in the fit over a PL.
Check the BB fit.
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    1.464    0.737    -      -           4.15e-03 1.79e-03   42.870 57
CPL   0.324    1.051      70.1    0.0      1.64e-02 3.47e+02   42.580 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: 345.280000 sec.
T50 in the 50-300 keV band: 159.168000 sec.

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100  513.824  -13.864  499.960
T90   416.800   25.372  442.172
T50   187.084  116.704  303.788
Peak    1.000  178.796  179.796

Click here for the BAT GCN circular template

Image

Pre-slew 15-350 keV image (Event data; bkg subtracted)

#   RAcent  DECcent POSerr  Theta    Phi     Peak Cts     SNR  Name
   87.8727 -10.5261 0.0621   16.5   69.4      14.2318     3.1  TRIG_00638589       
------------------------------------------
 
Foreground time interval of the image:
-13.864 154.480 (delta_t = 168.344 [sec])
156.000 419.040 (delta_t = 263.040 [sec])
420.000 495.301 (delta_t =  75.301 [sec])
Background time interval of the image:
-16.499 -13.864 (delta_t =   2.635 [sec])

Lightcurves

Notes:

1) All plots contain as much data as has been downloaded to date.
2) The mask-weighted light curves are using the flight position.
3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
4) 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.
5) 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.
6) 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)

Spectra

Notes:

1) The fitting includes the systematic errors.
2) For long bursts, a spectral fit of 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.
4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.

Time averaged spectrum fit using the pre-slew DRM

Power-law model

Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.69358     (     )
Norm@50keV  : 1.03676E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         156.59 using 59 PHA bins.
# Reduced chi-squared =         2.7473 for     57 degrees of freedom 
# Null hypothesis probability =   3.154577e-11
 
Photon flux (15-150 keV)    in 511.3 sec: 0.137386 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.91059e-06 ( 0  0 ) ergs/cm2

Cutoff power-law model

Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.24575     (     )
Epeak [keV] : 38.4466      (   )
Norm@50keV  : 0.296500    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         125.58 using 59 PHA bins.
# Reduced chi-squared =         2.2425 for     56 degrees of freedom 
# Null hypothesis probability =   2.968989e-07
 
Photon flux (15-150 keV)    in 511.3 sec: 0.120105 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.28802e-06 ( 0  0 ) ergs/cm2

Band function

Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 4.16521   ( -1.60349   -4.07021 )
beta        : -2.80774    ( -0.492802   0.373988 )
Epeak [keV] : 34.8712      ( -2.12474 1.93128 )
Norm@50keV   : 6.18980    ( -6.18996   13.2445 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          98.54 using 59 PHA bins.
# Reduced chi-squared =          1.792 for     55 degrees of freedom 
# Null hypothesis probability =   2.840804e-04
 
Photon flux (15-150 keV)    in 511.3 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]    : 10.0460  (  )
R^2/D10^2   : 6.75239E-02  (   )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =         127.88 using 59 PHA bins.
# Reduced chi-squared =         2.2436 for     57 degrees of freedom 
# Null hypothesis probability =   2.327183e-07
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.107e-07   7.030e-08
25- 50  1.779e-06   1.232e-07
50-150  9.406e-07   1.664e-07
15-150  3.430e-06   2.531e-07

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 105.109       (      )
Norm        : 0.602481       (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         148.69 using 59 PHA bins.
# Reduced chi-squared =         2.6086 for     57 degrees of freedom 
# Null hypothesis probability =   4.064731e-10
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.050e-07   8.155e-08
25- 50  1.406e-06   1.117e-07
50-150  2.342e-06   7.422e-07
15-150  4.553e-06   8.508e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 4.03925E-02        (      )
R1^2/D10^2  : 3.53524E+17        (      )
kT2 [keV]   : 10.0459        (      )
R2^2/D10^2  : 6.75243E-02    (   )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         127.88 using 59 PHA bins.
# Reduced chi-squared =         2.3252 for     55 degrees of freedom 
# Null hypothesis probability =   9.756558e-08
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  0.000e+00   0.000e+00
25- 50  0.000e+00   0.000e+00
50-150  0.000e+00   0.000e+00
15-150  0.000e+00   0.000e+00

Peak spectrum fit

Power-law model

Time interval is from  178.796 sec. to  179.796 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.46350     ( -0.695853   0.778114 )
Norm@50keV  : 4.14857E-03    ( -0.00185269   0.0017305 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.87 using 59 PHA bins.
# Reduced chi-squared =         0.7520 for     57 degrees of freedom 
# Null hypothesis probability =   9.175008e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.512989 ( -0.19915  0.19915 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.96018e-08 ( -1.84058e-08  1.97105e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from  178.796 sec. to  179.796 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.323642     ( -0.321702   1.78073 )
Epeak [keV] : 70.1391      ( -70.0963 -70.0963 )
Norm@50keV  : 1.63877E-02    ( -0.0164474   693.666 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.58 using 59 PHA bins.
# Reduced chi-squared =         0.7604 for     56 degrees of freedom 
# Null hypothesis probability =   9.069206e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.491741 ( -0.227639  0.207528 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.61081e-08 ( -1.70072e-08  2.21775e-08 ) ergs/cm2

Band function

Time interval is from  178.796 sec. to  179.796 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -0.791390   ( 0.886921   5.73655 )
beta        : -9.45687    ( 9.99329   19.9933 )
Epeak [keV] : 86.0793      ( -52.6479 -86.0793 )
Norm@50keV   : 9.33164E-03    ( -0.00362076   0.00362076 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.62 using 59 PHA bins.
# Reduced chi-squared =         0.7749 for     55 degrees of freedom 
# Null hypothesis probability =   8.883274e-01
 
Photon flux (15-150 keV)    in 1 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]    : 14.7617  (-4.86813  8.36376)
R^2/D10^2   : 6.57137E-02  (-0.0657137   0.190181)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.84 using 59 PHA bins.
# Reduced chi-squared =         0.7516 for     57 degrees of freedom 
# Null hypothesis probability =   9.178902e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  3.006e-09   1.930e-09
25- 50  1.176e-08   7.725e-09
50-150  1.732e-08   1.270e-08
15-150  3.209e-08   1.993e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 199.363       (-199.363      -199.363)
Norm        : 2.09740       (-0.812207     0.812424)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.78 using 59 PHA bins.
# Reduced chi-squared =         0.7505 for     57 degrees of freedom 
# Null hypothesis probability =   9.190058e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  5.223e-09   3.428e-09
25- 50  1.005e-08   6.480e-09
50-150  2.203e-08   1.443e-08
15-150  3.730e-08   2.400e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 2.39292        (-2.3737      17.4735)
R1^2/D10^2  : 61.1433        (-87.2676      639.348)
kT2 [keV]   : 16.5233        (-5.74997      11.3484)
R2^2/D10^2  : 4.12372E-02    (-0.0421536   0.14226)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          41.31 using 59 PHA bins.
# Reduced chi-squared =         0.7511 for     55 degrees of freedom 
# Null hypothesis probability =   9.142431e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.736e-09   2.087e-09
25- 50  1.014e-08   6.110e-09
50-150  1.929e-08   1.196e-08
15-150  3.416e-08   2.052e-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: 1.70004     (     )
Norm@50keV  : 1.04053E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         158.09 using 59 PHA bins.
# Reduced chi-squared =         2.7734 for     57 degrees of freedom 
# Null hypothesis probability =   1.932275e-11
 
Photon flux (15-150 keV)    in 506.7 sec: 0.138196 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.88161e-06 ( 0  0 ) ergs/cm2

Cutoff power-law model

Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.39289     (     )
Epeak [keV] : 38.1887      (   )
Norm@50keV  : 0.373115    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         125.33 using 59 PHA bins.
# Reduced chi-squared =         2.2380 for     56 degrees of freedom 
# Null hypothesis probability =   3.196273e-07
 
Photon flux (15-150 keV)    in 506.7 sec: 0.120578 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.26071e-06 ( 0  0 ) ergs/cm2

Band function

 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 4.25094   ( -1.76859   -4.25092 )
beta        : -2.84095    ( -0.503916   0.3848 )
Epeak [keV] : 34.8421      ( -2.08985 1.88125 )
Norm@50keV   : 7.07252    ( -7.08074   2.21494 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          99.30 using 59 PHA bins.
# Reduced chi-squared =          1.805 for     55 degrees of freedom 
# Null hypothesis probability =   2.362057e-04
 
Photon flux (15-150 keV)    in 506.7 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)  = 1.33e-06
S(50-100 keV) = 1.64e-06

T90 vs. Hardness ratio plot

T90                                   = 416.799999952316 sec.
Hardness ratio (energy fluence ratio) = 1.23308

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.91487
Count Ratio (50-100 keV) / (15-25 keV) = 0.587323

Mask shadow pattern

IMX = 1.040894911568212E-01, IMY = -2.763649725072458E-01

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:
-16.499400 -13.864000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.4949  22.0347    2.0  34.2   -3.2   0.1388   5.7    7.8	Crab                          
 83.1928 -55.1145    2.2  46.2  146.5   0.3575   5.2 ------	UNKNOWN                       
 45.3755  16.5243    1.9  36.7  -68.1   0.2551   6.1 ------	UNKNOWN

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

Time interval of the image:
-13.864000 154.480000
156.000000 419.040000
420.000000 495.300600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.7971  22.1066    6.0  34.4   -3.0   9.1532   1.9   10.7	Crab                          
 96.6924 -15.0568    2.5  25.4   80.1  26.2490   4.7 ------	UNKNOWN                       
 82.8633  10.3153    2.9  23.4    6.1  16.4485   4.0 ------	UNKNOWN                       
 48.8827 -40.4788    1.8  36.3 -174.9  32.8088   6.3 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
533.600590 963.060000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6436  22.0218    0.3  32.7  -25.7  17.5714  36.9    0.7	Crab                          
107.6058 -49.3297    2.7  42.3  142.3   4.9885   4.3 ------	UNKNOWN                       
118.7405  21.6034    3.1  44.1   24.8   3.5223   3.7 ------	UNKNOWN                       
 84.5460 -11.4025    3.3   3.3 -126.2   1.3567   3.5 ------	UNKNOWN                       
 45.0019 -40.4985    2.9  48.2 -154.7   3.9673   4.0 ------	UNKNOWN

Plot creation:
Tue Apr 21 18:41:40 EDT 2015