GRB090102: 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: Sat May  9 19:04:13 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger338895
======================================================================

  Trigger: 00338895      Segment: 000

  BAT Trigger Time: 252557749.248   [s; MET]
      Trigger Stop: 252557751.296   [s; MET]
               UTC: 2009-01-02T02:55:44.865380    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 128.258919212618   Dec: 33.0915130874167  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.37
     Image Trigger?:     NO
     Rate S/N Ratio:     77.517739905134  [ if not an image trigger ]
     Image S/N Ratio:    9.37

  Analysis Position:   [ source = BAT ]
    RA: 128.258919212618   Dec: 33.0915130874167  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 128.247387036973   Dec: 33.1077849115167  [deg; J2000]  
        { 08h 32m 59.4s , +33d 06' 28.0" }
         +/- 1.26481692995552 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.550582427740074 [arcmin] (formal 1-sigma fit error)
    SNR: 21.7452580368133
 
  Angular difference between the analysis and refined position is 1.135416 arcmin
 
  Partial Coding Fraction: 0.06835938    [ including projection effects ]

  Duration
     T90: 28.3199999928474 +/- 2.34567860066996
        Measured from: -11.6960000097752
                   to: 16.6239999830723     [s; relative to TRIGTIME]
     T50: 12.0639999806881 +/- 1.51898913226029
        Measured from: -6.52799999713898
                   to: 5.53599998354912     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.68400001525879     
                   to: 2.68400001525879     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -14.255999982357     
                   to: 22.7520000040531     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     2.059411   3.418273   3.105243   1.472189
           0.142032   0.155431   0.148263   0.125256 [error]
 Peak      0.084086   0.234566   0.285712   0.135476
           0.024096   0.030848   0.034590   0.030165 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   37.008  -14.256   22.752
T90    28.320  -11.696   16.624
T50    12.064   -6.528    5.536
Peak    1.000    1.684    2.684
 
 
====== 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      -1.326    -0.087      0.088       -           -               -         1.94e-02     -9.40e-04          9.40e-04      55.840   57
CPL     -1.238    -0.131      0.315      443.773    -292.877      -443.773      2.13e-02     -2.68e-03          7.87e-03      55.900   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      -0.914     -0.230     0.238       -           -               -         4.82e-02     -6.85e-03          6.81e-03      64.670   57
CPL     -0.322     -0.700     1.165      162.108    -162.108      -162.108      8.93e-02     -4.60e-02          2.00e-01      63.540   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   7.80e-07  1.60e-06  2.54e-06  9.04e-06  7.06e-06  1.40e-05   erg/cm2
      90%_error_low -7.35e-08 -9.03e-08 -1.47e-07 -1.13e-06 -3.67e-07 -1.22e-06   erg/cm2
      90%_error_hi   7.60e-08  8.97e-08  1.46e-07  1.24e-06  3.68e-07  1.31e-06   erg/cm2
Peak flux       PL   3.56e-04  4.45e-03  4.64e-02  4.31e+00  2.09e-01  3.98e+00   ph/cm2/s
      90%_error_low -4.73e-05 -6.30e-04 -3.22e-03 -5.57e-01 -1.33e-02 -3.18e-01   ph/cm2/s
      90%_error_hi   5.48e-04  5.56e-03  5.47e-02  2.92e+00  2.24e-01  4.41e+00   ph/cm2/s
 
Fluence        CPL   7.71e-07  1.60e-06  2.56e-06  8.41e-06  7.04e-06  1.33e-05   erg/cm2
      90%_error_low -9.21e-08 -9.06e-08 -1.57e-07 -3.03e-06 -3.87e-07 -3.00e-06   erg/cm2
      90%_error_hi   7.14e-08  9.89e-08  1.71e-07  9.21e-07  3.47e-07  7.38e-07   erg/cm2
Peak flux      CPL   9.81e-01  1.69e+00  1.85e+00  1.93e+00  5.45e+00  6.46e+00   ph/cm2/s
      90%_error_low -3.65e-01 -3.15e-01 -3.31e-01 -1.11e+00 -7.97e-01 -1.38e+00   ph/cm2/s
      90%_error_hi   4.08e-01  3.25e-01  3.41e-01  1.85e+00  7.98e-01  2.07e+00   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  128.2474    33.1078   0.0089    45.2149    46.1530        10.7360376     21.745 TRIG_00338895                 
 
Foreground time interval of the image:
-14.256  22.752 (delta_t =  37.008 [sec])
Background time interval of the image:
-239.248 -14.256 (delta_t = 224.992 [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  -14.256 sec. to   22.752 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.32607     ( -0.0873017   0.0875823 )
Norm@50keV  : 1.94311E-02    ( -0.000939982   0.000939932 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          55.84 using 59 PHA bins.
# Reduced chi-squared =         0.9797 for     57 degrees of freedom 
# Null hypothesis probability =   5.186218e-01
 
Photon flux (15-150 keV)    in 37.01 sec: 2.32971 ( -0.12029  0.12071 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.06317e-06 ( -3.66963e-07  3.67858e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -14.256 sec. to   22.752 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.23758     ( -0.0958236   0.35009 )
Epeak [keV] : 443.773      ( -622.221 -773.117 )
Norm@50keV  : 2.13419E-02    ( -0.00186135   0.00868258 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          55.90 using 59 PHA bins.
# Reduced chi-squared =         0.9983 for     56 degrees of freedom 
# Null hypothesis probability =   4.784851e-01
 
Photon flux (15-150 keV)    in 37.01 sec: 2.32347 ( -0.12618  0.1219 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.04463e-06 ( -3.86703e-07  3.46979e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.684 sec. to    2.684 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.914033     ( -0.229788   0.23827 )
Norm@50keV  : 4.81874E-02    ( -0.00684933   0.00681353 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.67 using 59 PHA bins.
# Reduced chi-squared =          1.135 for     57 degrees of freedom 
# Null hypothesis probability =   2.265948e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.209247 0.233176 0.230057 0.227737 0.143366 3.00678E-02 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.37935e-07 ( -8.14148e-08  8.18628e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.684 sec. to    2.684 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.322115     ( -0.700481   1.16481 )
Epeak [keV] : 162.108      ( -162.109 -162.109 )
Norm@50keV  : 8.92581E-02    ( -0.04599   0.200043 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.54 using 59 PHA bins.
# Reduced chi-squared =          1.135 for     56 degrees of freedom 
# Null hypothesis probability =   2.279862e-01
 
Photon flux (15-150 keV)    in 1 sec: 5.45168 ( -0.79749  0.79841 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 28.32 sec.
Hardness ratio (energy fluence ratio) = 1.5954382716

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

S(15-50 keV)  = 2.3754724e-06
S(50-150 keV) = 4.687687e-06

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 = 6.979517698096455E-01, IMY = -7.266237093925275E-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:
-239.248000 -14.256000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
158.1936  44.4091    4.2  46.5   10.0   0.9803   2.8 ------	UNKNOWN                       
 24.1922  23.8122    3.0  54.3  177.0   2.6067   3.8 ------	UNKNOWN                       
179.8395  49.5272    2.7  49.6  -10.6   1.5505   4.2 ------	UNKNOWN                       
353.1461  68.7216    2.2  28.8 -115.4   1.1970   5.3 ------	UNKNOWN                       
201.1524  56.8802    2.5  48.9  -29.9   1.8208   4.6 ------	UNKNOWN                       

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

Time interval of the image:
-14.256000 22.752000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
128.2473  33.1078    0.6  45.2   46.2  10.7396  18.5 ------	UNKNOWN                       
163.7785  37.0060    3.5  55.0    9.9   2.0457   3.3 ------	UNKNOWN                       
  5.8930  35.0414    2.4  50.8 -158.8   0.7782   4.8 ------	UNKNOWN                       
274.8408  70.3363    2.1  41.5  -75.8   1.3632   5.5 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
375.352620 962.783300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 72.3160  36.8611    2.3  45.4  129.5   6.9552   5.0 ------	UNKNOWN                       
142.9070 -18.8049    3.1  53.7    0.9   4.4450   3.7 ------	UNKNOWN                       
186.2254  57.6262    2.6  45.7 -122.4   7.3549   4.5 ------	UNKNOWN