Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Mon Jan 20 03:53:45 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger305288
======================================================================

  Trigger: 00305288      Segment: 000

  BAT Trigger Time: 226831081.28   [s; MET]
      Trigger Stop: 226831082.304   [s; MET]
               UTC: 2008-03-10T08:37:58.647320    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 220.080833938862   Dec: -0.16550263482074  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.4
     Image Trigger?:     NO
     Rate S/N Ratio:     12.6095202129185  [ if not an image trigger ]
     Image S/N Ratio:    7.4

  Analysis Position:   [ source = BAT ]
    RA: 220.080833938862   Dec: -0.16550263482074  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 220.041401479246   Dec: -0.164600635023981  [deg; J2000]  
        { 14h 40m 09.9s , -00d 09' 52.6" }
         +/- 1.41133487449804 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.567822637128773 [arcmin] (formal 1-sigma fit error)
    SNR: 18.5934993333383
 
  Angular difference between the analysis and refined position is 2.366557 arcmin
 
  Partial Coding Fraction: 0.6875    [ including projection effects ]

  Duration
     T90: 363.212000012398 +/- 16.901348818458
        Measured from: -57.8400000035763
                   to: 305.372000008821     [s; relative to TRIGTIME]
     T50: 250.439999997616 +/- 9.34432640524042
        Measured from: -6.40799999237061
                   to: 244.032000005245     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.27199998497963     
                   to: 2.27199998497963     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -71.7639999985695     
                   to: 318.395999997854     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.964360   1.861515   0.739705   0.051445
           0.113777   0.107909   0.095548   0.087318 [error]
 Peak      0.050018   0.066276   0.028520   0.003760
           0.007242   0.007143   0.006060   0.004961 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  390.160  -71.764  318.396
T90   363.212  -57.840  305.372
T50   250.440   -6.408  244.032
Peak    1.000    1.272    2.272
 
 
====== 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      -2.218    -0.149      0.143       -           -               -         6.27e-04     -6.20e-05          6.12e-05      54.520   57
CPL     -1.650    -0.355      0.755       23.284     -22.756        11.380      1.39e-03     -5.96e-04          2.70e-03      51.930   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      -1.913     -0.239     0.226       -           -               -         9.16e-03     -1.47e-03          1.44e-03      58.390   57
CPL     -0.718     -1.109     1.575       43.814     -11.657        43.804      4.58e-02     -4.58e-02          3.56e-01      54.960   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   6.16e-07  7.33e-07  6.31e-07  9.24e-07  2.31e-06  2.90e-06   erg/cm2
      90%_error_low -6.07e-08 -5.31e-08 -8.50e-08 -2.23e-07 -1.93e-07 -3.30e-07   erg/cm2
      90%_error_hi   6.19e-08  5.31e-08  8.76e-08  2.70e-07  1.97e-07  3.65e-07   erg/cm2
Peak flux       PL   5.62e-01  4.43e-01  2.35e-01  1.81e-01  1.32e+00  1.42e+00   ph/cm2/s
      90%_error_low -1.04e-01 -5.83e-02 -4.82e-02 -6.22e-02 -1.75e-01 -1.89e-01   ph/cm2/s
      90%_error_hi   1.08e-01  5.83e-02  4.89e-02  7.93e-02  1.75e-01  1.89e-01   ph/cm2/s
 
Fluence        CPL   5.94e-07  7.77e-07  6.23e-07  8.04e-07  2.26e-06  2.90e-06   erg/cm2
      90%_error_low -6.66e-08 -6.97e-08 -7.76e-08    N/A    -1.46e-07 -3.06e-07   erg/cm2
      90%_error_hi   6.65e-08  7.25e-08  9.51e-08    N/A     2.52e-07  5.04e-07   erg/cm2
Peak flux      CPL   5.06e-01  5.08e-01  2.26e-01  4.26e-02  1.27e+00  1.28e+00   ph/cm2/s
      90%_error_low -1.21e-01 -8.35e-02 -6.71e-02 -4.26e-02 -1.80e-01 -1.86e-01   ph/cm2/s
      90%_error_hi   1.21e-01  8.88e-02  5.90e-02  1.19e-01  1.80e-01  1.98e-01   ph/cm2/s
 
======================================================================
  • Special notes of this burst




    Image

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

    #   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
      220.0414    -0.1646   0.0103    27.7807   158.1826         2.2877529     18.593 TRIG_00305288                 
     
    Foreground time interval of the image:
    -52.979  18.421 (delta_t =  71.400 [sec])
    Background time interval of the image:
    




    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

    Bokeh Plot

    Other quick-look light curves:




    Spectra

    Notes:

    Time averaged spectrum fit using the average DRM

    Power-law model
    Time interval is from  -71.764 sec. to  318.396 sec.
     
    Spectral model in power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: -2.21769     ( -0.148643   0.143073 )
    Norm@50keV  : 6.27201E-04    ( -6.1967e-05   6.12051e-05 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          54.52 using 59 PHA bins.
    # Reduced chi-squared =         0.9565 for     57 degrees of freedom 
    # Null hypothesis probability =   5.686496e-01
     
    Photon flux (15-150 keV)    in 390.2 sec: 0.104821 ( -0.0074481  0.007453 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.30737e-06 ( -1.93164e-07  1.96936e-07 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from  -71.764 sec. to  318.396 sec.
    Spectral model in the cutoff power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: -1.65027     ( -0.355173   0.754225 )
    Epeak [keV] : 23.2837      ( -22.7775 11.3587 )
    Norm@50keV  : 1.39154E-03    ( -0.000597744   0.00269357 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          51.93 using 59 PHA bins.
    # Reduced chi-squared =         0.9273 for     56 degrees of freedom 
    # Null hypothesis probability =   6.297706e-01
     
    Photon flux (15-150 keV)    in 390.2 sec: 0.102073 ( -0.0079764  0.007974 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.25651e-06 ( -1.4571e-07  2.51892e-07 ) ergs/cm2
     
    

    1-s peak spectrum fit

    Power-law model
    Time interval is from    1.272 sec. to    2.272 sec.
     
    Spectral model in power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: -1.91347     ( -0.239108   0.225619 )
    Norm@50keV  : 9.16071E-03    ( -0.00146898   0.00143629 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          58.39 using 59 PHA bins.
    # Reduced chi-squared =          1.024 for     57 degrees of freedom 
    # Null hypothesis probability =   4.240407e-01
     
    Photon flux (15-150 keV)    in 1 sec: 1.32232 ( -0.1747  0.17475 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 8.42481e-08 ( -1.3035e-08  1.33182e-08 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from    1.272 sec. to    2.272 sec.
    Spectral model in the cutoff power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: -0.718262     ( -1.10883   1.5743 )
    Epeak [keV] : 43.8140      ( -11.6547 43.8061 )
    Norm@50keV  : 4.58388E-02    ( -0.0458623   0.356411 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          54.96 using 59 PHA bins.
    # Reduced chi-squared =         0.9813 for     56 degrees of freedom 
    # Null hypothesis probability =   5.144269e-01
     
    Photon flux (15-150 keV)    in 1 sec: 1.27451 ( -0.18017  0.18042 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 7.51917e-08 ( -1.39905e-08  1.54922e-08 ) ergs/cm2
     
    

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot

    T90                                   = 363.212 sec.
    Hardness ratio (energy fluence ratio) = 0.859983407061
    

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

    S(15-50 keV)  = 1.3494536e-06
    S(50-150 keV) = 9.579154e-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 = -4.890763693368319E-01, IMY = -1.957889539151486E-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:
     
    

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

    Time interval of the image:
    -52.979410 18.420600
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    170.2158 -60.7081    7.0  44.2   -8.3   0.2835   1.7    5.9	Cen X-3                       
    187.0917 -62.7880    5.3  39.5  -18.4   0.3002   2.2   12.0	GX 301-2                      
    244.9760 -15.6467    0.3  31.7 -141.5   4.0246  34.3    0.4	Sco X-1                       
    256.0170 -37.9750    6.0  37.4  -98.9   0.4711   1.9    8.0	4U 1700-377                   
    256.2837 -36.2926    5.7  37.5 -101.7   0.5144   2.0   10.7	GX 349+2                      
    263.0094 -24.7461   78.5  44.6 -118.2  -0.0566  -0.1    0.0	GX 1+4                        
    220.0414  -0.1646    0.6  27.8  158.2   2.2880  18.6 ------	UNKNOWN                       
    226.0544   2.7072    2.2  32.3  167.9   0.6764   5.3 ------	UNKNOWN                       
    248.8935 -69.3576    2.7  47.1  -53.2   1.7976   4.3 ------	UNKNOWN                       
    263.4887 -18.9675    2.4  46.8 -125.7   1.9235   4.7 ------	UNKNOWN                       
    

    Post-slew image of 15-350 keV band

    Time interval of the image:
    77.820590 962.786400
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    244.9716 -15.6393    0.2  29.0  -61.7  51.3216  70.9    0.5	Sco X-1                       
    254.4613  35.2392    5.0  47.8 -146.6   3.1228   2.3    6.2	Her X-1                       
    256.0191 -37.8089    3.5  50.1  -42.3   7.4219   3.3    2.6	4U 1700-377                   
    256.4638 -36.4250    9.8  49.5  -44.0   2.5532   1.2    1.4	GX 349+2                      
    189.4888  25.4800    4.4  39.1  128.2   4.3322   2.6 ------	UNKNOWN                       
    220.1032  -0.1698    1.9   0.0 -131.1   3.1295   6.1 ------	UNKNOWN                       
    229.4442 -58.2514    2.3  58.5  -10.8  15.2502   5.0 ------	UNKNOWN                       
    261.0784  -1.7162    3.0  41.0  -92.7  10.2816   3.9 ------	UNKNOWN