GRB090519: 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 Jan 19 16:31:31 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger352648
======================================================================

  Trigger: 00352648      Segment: 000

  BAT Trigger Time: 264460141.184   [s; MET]
      Trigger Stop: 264460153.344   [s; MET]
               UTC: 2009-05-19T21:08:56.428660    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 142.292608313677   Dec: 0.182991992937532  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.61
     Image Trigger?:     NO
     Rate S/N Ratio:     13.6747943311773  [ if not an image trigger ]
     Image S/N Ratio:    8.61

  Analysis Position:   [ source = BAT ]
    RA: 142.292608313677   Dec: 0.182991992937532  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 142.309062770082   Dec: 0.185176383180289  [deg; J2000]  
        { 09h 29m 14.2s , +00d 11' 06.6" }
         +/- 1.97870528261701 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.781407827699815 [arcmin] (formal 1-sigma fit error)
    SNR: 11.4740513635122
 
  Angular difference between the analysis and refined position is 0.995924 arcmin
 
  Partial Coding Fraction: 0.578125    [ including projection effects ]

  Duration
     T90: 58.0360000133514 +/- 8.18314682376177
        Measured from: -10.863999992609
                   to: 47.1720000207424     [s; relative to TRIGTIME]
     T50: 26.0920000076294 +/- 12.8469646408324
        Measured from: -4.24799999594688
                   to: 21.8440000116825     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -10.4039999842644     
                   to: -9.40399998426437     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -12.3999999761581     
                   to: 54.8880000114441     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.287525   0.518887   0.563350   0.230266
           0.055707   0.057391   0.051980   0.046681 [error]
 Peak      0.010710   0.017326   0.034327   0.014305
           0.006742   0.007244   0.006732   0.006399 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   67.288  -12.400   54.888
T90    58.036  -10.864   47.172
T50    26.092   -4.248   21.844
Peak    1.000  -10.404   -9.404
 
 
====== 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      -0.852    -0.199      0.210       -           -               -         1.53e-03     -1.73e-04          1.70e-04      63.780   57
CPL     -0.781    -0.272      0.519      995.501    -995.501      -995.501      1.65e-03     -2.77e-04          5.64e-05      64.020   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      -0.307     -0.564     0.721       -           -               -         4.61e-03     -1.84e-03          1.62e-03      46.240   57
CPL     -0.199     -0.681     2.187      974.581    -974.581      -974.581      5.16e-03     -2.36e-03          -5.16e-03      46.420   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   7.20e-08  1.97e-07  4.38e-07  2.56e-06  1.18e-06  3.27e-06   erg/cm2
      90%_error_low -1.73e-08 -2.92e-08 -4.87e-08 -6.37e-07 -1.31e-07 -6.58e-07   erg/cm2
      90%_error_hi   1.89e-08  2.85e-08  4.82e-08  7.97e-07  1.32e-07  8.01e-07   erg/cm2
Peak flux       PL   6.13e-02  1.27e-01  2.05e-01  7.42e-01  5.67e-01  1.14e+00   ph/cm2/s
      90%_error_low -4.19e-02 -1.27e-01 -5.28e-02 -3.65e-01 -1.56e-01 -3.55e-01   ph/cm2/s
      90%_error_hi   6.58e-02  6.79e-02  5.14e-02  6.58e-01  1.61e-01  5.62e-01   ph/cm2/s
 
Fluence        CPL   7.30e-08  1.97e-07  4.29e-07  2.72e-06  1.19e-06  3.23e-06   erg/cm2
      90%_error_low -2.84e-08 -3.26e-08    N/A    -1.43e-06    N/A    -1.23e-06   erg/cm2
      90%_error_hi   1.98e-08  3.26e-08    N/A     1.91e-07    N/A     3.68e-07   erg/cm2
Peak flux      CPL   6.11e-02  1.27e-01  2.05e-01  7.31e-01  5.67e-01  1.18e+00   ph/cm2/s
      90%_error_low     N/A       N/A       N/A       N/A   -1.57e-01 -5.87e-01   ph/cm2/s
      90%_error_hi      N/A       N/A       N/A       N/A    1.60e-01  5.00e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  142.3091     0.1852   0.0166    22.3988    75.1332         1.6790839     11.474 TRIG_00352648                 
 
Foreground time interval of the image:
-12.400  54.888 (delta_t =  67.288 [sec])
Background time interval of the image:
-100.683 -12.400 (delta_t =  88.283 [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  -12.400 sec. to   54.888 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.851553     ( -0.19913   0.210162 )
Norm@50keV  : 1.53258E-03    ( -0.000173097   0.000170094 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.78 using 59 PHA bins.
# Reduced chi-squared =          1.119 for     57 degrees of freedom 
# Null hypothesis probability =   2.502981e-01
 
Photon flux (15-150 keV)    in 67.29 sec: 0.175922 ( -0.019452  0.019577 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.17992e-06 ( -1.31315e-07  1.31892e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -12.400 sec. to   54.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.844738     ( -0.272217   0.519396 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 1.54295E-03    ( -0.000173613   0.000160214 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.80 using 59 PHA bins.
# Reduced chi-squared =          1.139 for     56 degrees of freedom 
# Null hypothesis probability =   2.212563e-01
 
Photon flux (15-150 keV)    in 67.29 sec: 0.175871 ( -0.019453  0.019534 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.18932e-06 ( 0  0 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from  -10.404 sec. to   -9.404 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.30749     ( -0.564186   0.720879 )
Norm@50keV  : 4.60667E-03    ( -0.00184327   0.00162289 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.24 using 59 PHA bins.
# Reduced chi-squared =         0.8113 for     57 degrees of freedom 
# Null hypothesis probability =   8.450420e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.567275 ( -0.156022  0.160547 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.85693e-08 ( -1.74423e-08  1.74231e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -10.404 sec. to   -9.404 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.293086     ( -0.6814   2.18567 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 4.64380E-03    ( -0.00184693   -0.00464544 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.26 using 59 PHA bins.
# Reduced chi-squared =         0.8260 for     56 degrees of freedom 
# Null hypothesis probability =   8.201719e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.567351 ( -0.157025  0.160115 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.80754e-08 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 58.036 sec.
Hardness ratio (energy fluence ratio) = 2.21676712101

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

S(15-50 keV)  = 2.6943265e-07
S(50-150 keV) = 9.104804e-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 = 1.057455153147989E-01, IMY = -3.983484153796124E-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:
-100.683400 -12.400000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6253  22.0064    1.4  41.2  -72.8   3.0824   8.2    0.7	Crab                          
135.5589 -40.5709    2.8  43.8  146.4   1.0272   4.1    1.7	Vela X-1                      
126.8493   5.1276    2.3   8.2   41.6   0.4775   5.1 ------	UNKNOWN                       
107.6359  14.9046    2.8  18.6  -56.5   0.4206   4.1 ------	UNKNOWN                       

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

Time interval of the image:
-12.400000 54.888000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.5011  22.1388    0.0  41.4  -72.7   0.5821   1.4   10.5	Crab                          
135.6966 -40.5323  107.0  43.8  146.3  -0.0289  -0.1    7.8	Vela X-1                      
142.3091   0.1852    1.0  22.4   75.1   1.6792  11.5 ------	UNKNOWN                       
138.4355  41.5117    2.2  44.0    3.7   1.0667   5.2 ------	UNKNOWN                       
136.3281  55.8719    2.9  56.6   -5.4   2.2762   3.9 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
104.316590 962.861100
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5667 -40.5687    0.7  41.2  168.0  14.1231  16.6    1.9	Vela X-1                      
150.6677 -13.0831    2.6  15.7  128.5   2.2942   4.4 ------	UNKNOWN                       
171.1154  49.6593    2.8  55.3    2.6  11.4742   4.1 ------	UNKNOWN                       
141.4419  -6.1069    2.4   6.4  167.8   2.4359   4.8 ------	UNKNOWN