batgrbproduct analysis for trigger=208654

Analysis for Ground-detected GRB: Trigger=208654

Analysis Summary

Notes:

1) No attempt has been made to eliminate the non-significant decimal places.
2) This is a special analysis for ground-detected GRB. The event data duration is likely to be shorter than the burst duration. In such cases, the burst durations are found using the quad-rate data, and spectral analyses are only available for event data range.
3) Some mask-weighted light curve plots might be missing because the time range is not completely covered by the event data range.

==========================================================================
           BAT GROUND-DETECTED GRB DATA PROCESSING REPORT                 
    Process Script: hand-made scripts that follow steps in batgrbproduct
                    but without using TDRSS info
    Process Start Time: Tue Sep 30 00:05:10 EDT 2014
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
==========================================================================
 
  BAT Trigger Time: 168503759.5
               UTC: 2006-05-05T06:35:58.326   [includes UTCF correction]
       Where From?: Ground analysis (best_duration.txt)
  NOTE: BAT trigger time for ground-detected burst is the T100 start time.
 
  Analysis Position:   [ source = GCN ]
    RA: 331.770   Dec: -27.824  [deg; J2000]
 
  Refined Position:   [ source = BAT pre-slew image ]
    RA: 331.77   Dec: -27.824  [deg; J2000]
        { 22h 07m 04.8s , -27d -49' -26.4" }
        +/- 2.94878043285 [arcmin] (estimated 90% radius based on SNR)
    SNR: 6.49019031309
 
  Angular difference between the GCN position (ra=331.770, dec=-27.824 deg) and this refined position is 0.001 arcmin
 
  Partial Coding Fraction: 1.113281e-01    [ including projection effects ]
 
  Duration (found by FRED-model fit)
     T90: 4 +/- N/A
        Measured from: 1
                   to: 5     [s; relative to TRIGTIME]
     T50: 1 +/- N/A
        Measured from: 2
                   to: 3
 
=== 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 7.82e-08 1.69e-07 2.88e-07 1.13e-06 7.91e-07 1.66e-06   erg/cm2
              Error 2.43e-08 3.21e-08 5.86e-08 5.10e-07 1.48e-07 5.48e-07   erg/cm2
Peak flux Power-law 5.12e-01 7.07e-01 7.22e-01 1.35e+00 2.37e+00 3.29e+00   ph/cm2/s
              Error 2.67e-01 2.28e-01 1.90e-01 7.71e-01 6.14e-01 8.91e-01   ph/cm2/s
 
Fluence   Cutoff-PL 6.84e-08 1.78e-07 3.06e-07 5.37e-07 7.68e-07 1.09e-06   erg/cm2
              Error 2.96e-08 3.71e-08 6.92e-08 6.46e-07 1.56e-07 7.36e-07   erg/cm2
Peak flux Cutoff-PL 4.26e-01 7.25e-01 7.83e-01 7.76e-01 2.32e+00 2.71e+00   ph/cm2/s
              Error 3.22e-01 2.55e-01 2.49e-01 9.71e-01 6.32e-01 1.15e+00   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    1.233    0.292    -      -           1.12e-02 1.90e-03   60.430 57
CPL   0.627    1.116     124.9    0.0      2.15e-02 3.96e-02   59.580 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    0.969    0.439    -      -           2.06e-02 5.27e-03   38.150 57
CPL   2.246    0.000      81.5    0.0      1.24e-03 0.00e+00   37.230 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

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100    7.000    0.000    7.000
T90     4.000    1.000    5.000
T50     1.000    2.000    3.000
Peak    1.000    2.400    3.400

Click here for the BAT GCN circular template

Special notes of this burst

Image

15.0-350.0 keV image (Event data)

#RAcent DECcent POSerr Theta  Phi  Peak_Cts  SNR Name
331.770 -27.824 0.000 49.716 22.125 1.004 6.490 TRIG_00208654
 
Image time interval: 0.000 to 7.000 [sec]

Lightcurves

Notes:

1) 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.
2) 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 (for the best duration plot, slew times are marked by green arrows).
3) For lightcurves in unit of count rate, time of each bin is in the middle of the bin.

Best duration plot

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)

Quad-rate summed light curves (from T0-300s to T0+1000s)

Spectral Evolution

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

Time interval is from    0.000 sec. to    7.000 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.23268     ( -0.292754   0.291193 )
Norm@50keV  : 1.12328E-02    ( -0.00189747   0.00189657 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.43 using 59 PHA bins.
# Reduced chi-squared =          1.060 for     57 degrees of freedom 
# Null hypothesis probability =   3.531757e-01
 
Photon flux (15-150 keV)    in 7 sec: 1.32488 ( -0.229249  0.229945 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.90566e-07 ( -1.47587e-07  1.4936e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.000 sec. to    7.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.626801     ( -1.39939   0.833217 )
Epeak [keV] : 124.923      ( -124.929 -124.929 )
Norm@50keV  : 2.14645E-02    ( -0.0117389   0.0675286 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.58 using 59 PHA bins.
# Reduced chi-squared =          1.064 for     56 degrees of freedom 
# Null hypothesis probability =   3.468939e-01
 
Photon flux (15-150 keV)    in 7 sec: 1.29215 ( -0.23716  0.2375 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.67585e-07 ( -1.5633e-07  1.56562e-07 ) ergs/cm2

Band function

Time interval is from    0.000 sec. to    7.000 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -0.690917   ( -0.435224   1.69998 )
beta        : -10.0000    ( 10   7.10543e-15 )
Epeak [keV] : 130.542      ( -59.4187 -130.904 )
Norm@50keV   : 2.03049E-02    ( -0.0105858   0.0690666 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.59 using 59 PHA bins.
# Reduced chi-squared =          1.083 for     55 degrees of freedom 
# Null hypothesis probability =   3.124880e-01
 
Photon flux (15-150 keV)    in 7 sec: 1.30481 (    ) 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]    : 19.0824  (-3.69327  4.8355)
R^2/D10^2   : 7.19373E-02  (-0.0377733   0.0747628)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.60 using 59 PHA bins.
# Reduced chi-squared =          1.133 for     57 degrees of freedom 
# Null hypothesis probability =   2.283731e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  3.599e-08   1.340e-08
25- 50  1.736e-07   4.714e-08
50-150  4.650e-07   1.557e-07
15-150  6.746e-07   1.753e-07

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 200.000       (-62.2853      -200)
Norm        : 5.48065       (-0.939778     0.939778)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.32 using 59 PHA bins.
# Reduced chi-squared =          1.111 for     57 degrees of freedom 
# Null hypothesis probability =   2.633377e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  9.554e-08   5.471e-08
25- 50  1.838e-07   1.065e-07
50-150  4.030e-07   2.268e-07
15-150  6.823e-07   3.924e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 6.92878        (-3.73356      5.84719)
R1^2/D10^2  : 1.02637        (-0.874503      21.0911)
kT2 [keV]   : 26.6601        (-7.6678      25.2601)
R2^2/D10^2  : 2.03489E-02    (-0.0180697   0.0470889)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.71 using 59 PHA bins.
# Reduced chi-squared =          1.067 for     55 degrees of freedom 
# Null hypothesis probability =   3.411065e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.180e-08   4.309e-08
25- 50  1.730e-07   9.145e-08
50-150  5.295e-07   3.081e-07
15-150  7.743e-07   4.116e-07

Peak spectrum fit

Power-law model

Time interval is from    2.400 sec. to    3.400 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.969326     ( -0.455161   0.423535 )
Norm@50keV  : 2.06213E-02    ( -0.00531855   0.00522984 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          38.15 using 59 PHA bins.
# Reduced chi-squared =         0.6694 for     57 degrees of freedom 
# Null hypothesis probability =   9.740646e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.37061 ( -0.612207  0.616389 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.25471e-07 ( -5.93872e-08  5.98868e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    2.400 sec. to    3.400 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.24640     (     )
Epeak [keV] : 81.4976      (   )
Norm@50keV  : 1.24426E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.23 using 59 PHA bins.
# Reduced chi-squared =         0.6649 for     56 degrees of freedom 
# Null hypothesis probability =   9.748406e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.31629 ( -0.63076  0.63401 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.20943e-07 ( -6.3191e-08  6.1877e-08 ) ergs/cm2

Band function

Time interval is from    2.400 sec. to    3.400 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -0.862735   ( 0.862703   0.862703 )
beta        : -0.969340    ( -0.423384   0.455255 )
Epeak [keV] : 24.9072      ( -25.0222 -25.0222 )
Norm@50keV   : 3.18037E-02    ( -0.0163074   3.48184 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          38.15 using 59 PHA bins.
# Reduced chi-squared =         0.6937 for     55 degrees of freedom 
# Null hypothesis probability =   9.592581e-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]    : 22.8034  (-6.18837  10.3203)
R^2/D10^2   : 7.80944E-02  (-0.0533607   0.136331)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.26 using 59 PHA bins.
# Reduced chi-squared =         0.6887 for     57 degrees of freedom 
# Null hypothesis probability =   9.648602e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.390e-09   4.740e-09
25- 50  3.990e-08   2.255e-08
50-150  1.550e-07   8.763e-08
15-150  2.023e-07   1.017e-07

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 200.000       (-75.3413      -200)
Norm        : 9.69796       (-2.54926     2.54926)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.14 using 59 PHA bins.
# Reduced chi-squared =         0.7568 for     57 degrees of freedom 
# Null hypothesis probability =   9.127508e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.416e-08   1.458e-08
25- 50  4.648e-08   2.792e-08
50-150  1.019e-07   6.185e-08
15-150  1.726e-07   1.014e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 1.43764        (-1.43188      2.34296)
R1^2/D10^2  : 1.83431E+04        (-18843.8      -18843.8)
kT2 [keV]   : 23.9522        (-6.64241      11.7409)
R2^2/D10^2  : 6.57690E-02    (-0.065773   0.0667862)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.56 using 59 PHA bins.
# Reduced chi-squared =         0.6828 for     55 degrees of freedom 
# Null hypothesis probability =   9.652929e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.256e-08   4.306e-09
25- 50  3.720e-08   2.115e-08
50-150  1.590e-07   9.285e-08
15-150  2.087e-07   1.154e-07

S(25-50 keV) vs. S(50-100 keV) plot

S(25-50 keV)  = 1.69e-07
S(50-100 keV) = 2.88e-07

T90 vs. Hardness ratio plot

T90                                   = 4 sec.
Hardness ratio (energy fluence ratio) = 1.70414

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.79602
Count Ratio (50-100 keV) / (15-25 keV) = 1.9801

Mask shadow pattern

IMX = 1.09294685563, IMY = -0.444347940544

TIME vs. PHA plot around the beginning of event data (event_start to event_start+0.64s)

TIME vs. DetID plot around the beginning of event data (event_start to event_start+0.64s)

100 us light curve (15-350 keV; (event_start to event_start+0.64s)

Spacecraft aspect plot

Bright source in the event data image

Event data image of 15-350 keV band

Time interval of the image:
0.000000 7.000000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.6225  35.3364    5.6  43.3  126.5  -0.4458  -2.1    8.2	Cyg X-1                       
308.0168  40.7461    0.0  38.2  137.1  -0.0236  -0.2   13.1	Cyg X-3                       
326.0748  38.2203   13.8  25.0  146.8   0.0468   0.8    7.6	Cyg X-2                       
331.7690 -27.8075    1.8  49.7   22.1   1.0202   6.5 ------	UNKNOWN                       
350.4120  11.4804    2.9   9.6  -22.2   0.1944   3.9 ------	UNKNOWN                       
 36.7464  50.2869    2.2  50.1 -134.0   1.1608   5.2 ------	UNKNOWN                       
 30.2566  24.5413    2.8  41.2  -99.1   0.7923   4.2 ------	UNKNOWN

Webpage updated on:
Wed Nov 25 17:11:47 EST 2015