GRB090107A: 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 19:13:41 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger339295
======================================================================

  Trigger: 00339295      Segment: 000

  BAT Trigger Time: 252996488.704   [s; MET]
      Trigger Stop: 252996489.728   [s; MET]
               UTC: 2009-01-07T04:48:04.308060    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 302.42575240314   Dec: 4.72746160298767  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.58
     Image Trigger?:     NO
     Rate S/N Ratio:     14.5258390463339  [ if not an image trigger ]
     Image S/N Ratio:    8.58

  Analysis Position:   [ source = BAT ]
    RA: 302.42575240314   Dec: 4.72746160298767  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 302.408099686857   Dec: 4.74714950259026  [deg; J2000]  
        { 20h 09m 37.9s , +04d 44' 49.7" }
         +/- 2.39365055667552 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.00073482208502 [arcmin] (formal 1-sigma fit error)
    SNR: 8.74184343645847
 
  Angular difference between the analysis and refined position is 1.584166 arcmin
 
  Partial Coding Fraction: 0.7421875    [ including projection effects ]

  Duration
     T90: 12.0840000212193 +/- 0.687069143455587
        Measured from: 0.495999991893768
                   to: 12.580000013113     [s; relative to TRIGTIME]
     T50: 10.472000002861 +/- 7.21137879261201
        Measured from: 1.06400001049042
                   to: 11.5360000133514     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.296000003814697     
                   to: 1.2960000038147     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.303999990224838     
                   to: 12.8959999978542     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.121868   0.169589   0.091084   0.021532
           0.021842   0.022806   0.020348   0.019389 [error]
 Peak      0.035155   0.049337   0.039704   0.004337
           0.006440   0.007042   0.006269   0.005548 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   12.592    0.304   12.896
T90    12.084    0.496   12.580
T50    10.472    1.064   11.536
Peak    1.000    0.296    1.296
 
 
====== 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      -1.637    -0.276      0.267       -           -               -         1.96e-03     -3.64e-04          3.58e-04      69.120   57
CPL      0.290    -1.430      2.467       48.770     -10.478        29.722      2.58e-02     -2.58e-02          8.41e-01      63.230   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      -1.406     -0.262     0.259       -           -               -         8.59e-03     -1.36e-03          1.35e-03      47.180   57
CPL     -0.810     -0.782     1.138       98.535     -39.258       -98.535      1.74e-02     -9.78e-03          4.71e-02      45.980   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   3.59e-08  6.07e-08  7.81e-08  2.02e-07  2.30e-07  3.77e-07   erg/cm2
      90%_error_low -8.36e-09 -1.00e-08 -1.86e-08 -8.19e-08 -4.47e-08 -1.04e-07   erg/cm2
      90%_error_hi   8.70e-09  1.00e-08  1.90e-08  1.13e-07  4.61e-08  1.29e-07   erg/cm2
Peak flux       PL   3.23e-01  3.44e-01  2.60e-01  3.19e-01  1.05e+00  1.25e+00   ph/cm2/s
      90%_error_low -7.97e-02 -5.57e-02 -5.16e-02 -1.11e-01 -1.61e-01 -1.99e-01   ph/cm2/s
      90%_error_hi   8.48e-02  5.51e-02  5.11e-02  1.44e-01  1.61e-01  2.03e-01   ph/cm2/s
 
Fluence        CPL   3.09e-08  7.59e-08  6.89e-08  1.56e-08  1.89e-07  1.91e-07   erg/cm2
      90%_error_low -9.50e-09 -1.51e-08 -3.14e-08 -1.46e-08 -4.45e-08 -4.67e-08   erg/cm2
      90%_error_hi   9.74e-09  1.65e-08  2.58e-08  7.37e-08  5.20e-08  8.49e-08   erg/cm2
Peak flux      CPL   2.93e-01  3.65e-01  2.72e-01  1.64e-01  1.02e+00  1.09e+00   ph/cm2/s
      90%_error_low -9.30e-02 -6.50e-02 -5.67e-02 -1.64e-01 -1.65e-01 -2.04e-01   ph/cm2/s
      90%_error_hi   9.65e-02  6.85e-02  5.86e-02  2.03e-01  1.65e-01  2.75e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  302.4081     4.7471   0.0220    22.4968   -63.6512         0.3837651      8.742 TRIG_00339295                 
 
Foreground time interval of the image:
  0.304  12.896 (delta_t =  12.592 [sec])
Background time interval of the image:
-239.704   0.304 (delta_t = 240.008 [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    0.304 sec. to   12.896 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.63677     ( -0.27627   0.266597 )
Norm@50keV  : 1.96367E-03    ( -0.000363724   0.00035791 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.12 using 59 PHA bins.
# Reduced chi-squared =          1.213 for     57 degrees of freedom 
# Null hypothesis probability =   1.302737e-01
 
Photon flux (15-150 keV)    in 12.59 sec: 0.255308 ( -0.042191  0.042199 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.3029e-07 ( -4.47379e-08  4.61022e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.304 sec. to   12.896 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.289647     ( -1.44305   2.45427 )
Epeak [keV] : 48.7701      ( -10.3306 29.8696 )
Norm@50keV  : 2.58351E-02    ( -0.0266397   0.840602 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.23 using 59 PHA bins.
# Reduced chi-squared =          1.129 for     56 degrees of freedom 
# Null hypothesis probability =   2.362983e-01
 
Photon flux (15-150 keV)    in 12.59 sec: 0.240567 ( -0.042597  0.043058 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.89084e-07 ( -4.45083e-08  5.20317e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    0.296 sec. to    1.296 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.40571     ( -0.26206   0.258618 )
Norm@50keV  : 8.59270E-03    ( -0.00136388   0.00135129 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.18 using 59 PHA bins.
# Reduced chi-squared =         0.8277 for     57 degrees of freedom 
# Null hypothesis probability =   8.199289e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.04781 ( -0.160601  0.16071 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.2943e-08 ( -1.46573e-08  1.49361e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.296 sec. to    1.296 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.80992     ( -0.781798   1.13823 )
Epeak [keV] : 98.5355      ( -39.2468 -98.524 )
Norm@50keV  : 1.73830E-02    ( -0.0097869   0.0470747 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.98 using 59 PHA bins.
# Reduced chi-squared =         0.8211 for     56 degrees of freedom 
# Null hypothesis probability =   8.278934e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.02494 ( -0.164519  0.16452 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.91444e-08 ( -1.5718e-08  1.60453e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 12.084 sec.
Hardness ratio (energy fluence ratio) = 1.28650072956

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

S(15-50 keV)  = 9.657269e-08
S(50-150 keV) = 1.3372136e-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 = 1.838131844421850E-01, IMY = 3.711207899623837E-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:
-239.704000 0.304000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
288.7764  10.9486    1.2  31.4  -36.8   2.3661   9.2    1.3	GRS 1915+105                  
299.5834  35.2056    0.4  24.4   19.3   6.7163  30.8    0.4	Cyg X-1                       
308.0854  40.9848    1.5  24.3   40.9   1.7815   7.8    2.2	Cyg X-3                       
326.2165  38.2234    5.9  19.9   77.6   0.4670   1.9    6.3	Cyg X-2                       
291.1140  57.4075    2.9  44.0   41.4   2.4341   4.0 ------	UNKNOWN                       
 13.4975   3.5339    2.9  54.3  163.3   4.5756   4.0 ------	UNKNOWN                       
269.2900  29.6840    2.8  47.2   -3.2   1.6774   4.1 ------	UNKNOWN                       
273.3747  -1.7047    3.0  50.5  -45.4   4.5677   3.9 ------	UNKNOWN                       
303.9722 -18.5668    3.7  40.9  -92.5   3.4882   3.2 ------	UNKNOWN                       

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

Time interval of the image:
0.304000 12.896000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
288.7902  10.9942   14.4  31.3  -36.7  -0.0372  -0.8    3.0	GRS 1915+105                  
299.5548  35.1749    6.3  24.4   19.2   0.0771   1.8    2.4	Cyg X-1                       
308.1380  40.8330   10.8  24.1   40.8   0.0504   1.1    7.3	Cyg X-3                       
326.1090  38.5187    0.0  20.1   77.1  -0.1023  -2.1   12.2	Cyg X-2                       
359.1220  42.7505    2.5  40.4  109.0   0.7263   4.7 ------	UNKNOWN                       
277.6106  16.2390    2.5  40.6  -23.5   0.2495   4.6 ------	UNKNOWN                       
302.4081   4.7472    1.3  22.5  -63.7   0.3837   8.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
368.396600 962.416000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6355  22.0080    0.2  24.3  122.7  26.1086  48.9    0.4	Crab                          
122.1008  28.7485    2.5  40.2   59.7   6.3705   4.7 ------	UNKNOWN                       
 52.1811   2.7798    2.7  47.1  174.1   3.8073   4.2 ------	UNKNOWN                       
107.0907  56.2953    2.8  22.6   11.3   1.7051   4.0 ------	UNKNOWN                       
178.7683  64.5774    3.3  55.1   -7.6   5.6271   3.5 ------	UNKNOWN                       
 32.7373  -0.0620    2.8  58.8 -166.0  12.1613   4.1 ------	UNKNOWN                       
234.8645  83.2232    4.3  51.1  -35.1   4.4877   2.7 ------	UNKNOWN                       
 11.5817  53.2742    3.8  40.9  -93.2   7.8230   3.1 ------	UNKNOWN