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
  147.5182   -42.3315   0.0189    34.1083    39.1001         1.1217662     10.133 TRIG_00548276                 
 
Foreground time interval of the image:
 -3.404  32.312 (delta_t =  35.716 [sec])
Background time interval of the image:
-239.368  -3.404 (delta_t = 235.964 [sec])
Lightcurves
Notes:
- 1) The mask-weighted light curves are using the flight position.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) 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.
- 5) Time of each bin is in the middle of the bin.
 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 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 8 ms binning
 From T100_start-3 s to T100_start+3 s
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 2 ms binning
 From T100_start-1 s to T100_start+1 s
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 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)
 
 The mask-weighted light curves based on cleaned DPHs 
 
Spectral Evolution
 
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   -3.404 sec. to   32.312 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.85273     ( -0.243409   0.255446 )
Norm@50keV  : 1.98432E-03    ( -0.000319047   0.000310529 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.91 using 59 PHA bins.
# Reduced chi-squared =          1.086 for     57 degrees of freedom 
# Null hypothesis probability =   3.051781e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.279226 ( -0.0382962  0.0383228 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.51704e-07 ( -1.03128e-07  1.0512e-07 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from   -3.404 sec. to   32.312 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.69212     ( -0.975154   0.617822 )
Epeak [keV] : 84.7419      ( -84.7195 -84.7409 )
Norm@50keV  : 2.44182E-03    ( -0.0024419   0.00615125 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.80 using 59 PHA bins.
# Reduced chi-squared =          1.104 for     56 degrees of freedom 
# Null hypothesis probability =   2.766341e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.277598 ( -0.039125  0.039092 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.41985e-07 ( -1.15451e-07  1.12343e-07 ) ergs/cm2
 
Band function
 
Time interval is from   -3.404 sec. to   32.312 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -1.69159   ( -1.88271   0.976414 )
beta        : -10.00000    ( 10   20 )
Epeak [keV] : 84.5992      ( -64.8234 -84.5992 )
Norm@50keV   : 2.44293E-03    ( -0.000331738   0.00614475 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.80 using 59 PHA bins.
# Reduced chi-squared =          1.124 for     55 degrees of freedom 
# Null hypothesis probability =   2.461835e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.276522 (    ) 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]    : 10.0939  (-1.67122  2.17989)
R^2/D10^2   : 0.124449  (-0.124072   0.124554)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          77.14 using 59 PHA bins.
# Reduced chi-squared =          1.353 for     57 degrees of freedom 
# Null hypothesis probability =   3.905770e-02
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  9.253e-08   2.329e-08
25- 50  2.331e-07   4.944e-08
50-150  1.250e-07   4.613e-08
15-150  4.506e-07   8.330e-08
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 90.7401       (-34.5502      82.0101)
Norm        : 1.26110       (-0.234648     0.311977)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.30 using 59 PHA bins.
# Reduced chi-squared =          1.093 for     57 degrees of freedom 
# Null hypothesis probability =   2.933605e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.176e-07   2.300e-08
25- 50  1.992e-07   3.490e-08
50-150  3.049e-07   1.581e-07
15-150  6.216e-07   1.904e-07
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 6.72477        (-1.66312      1.77879)
R1^2/D10^2  : 0.459382        (-0.267704      0.466036)
kT2 [keV]   : 29.0643        (-10.2906      29.9335)
R2^2/D10^2  : 1.82256E-03    (-0.00161677   0.00731299)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.62 using 59 PHA bins.
# Reduced chi-squared =          1.084 for     55 degrees of freedom 
# Null hypothesis probability =   3.113543e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.229e-07   6.457e-08
25- 50  1.978e-07   9.297e-08
50-150  3.430e-07   1.858e-07
15-150  6.637e-07   3.426e-07
Peak spectrum fit
Power-law model
 
Time interval is from   -1.580 sec. to   -0.580 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.55388     ( -0.465746   0.492169 )
Norm@50keV  : 5.96080E-03    ( -0.0017918   0.00176072 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.77 using 59 PHA bins.
# Reduced chi-squared =          1.224 for     57 degrees of freedom 
# Null hypothesis probability =   1.193639e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.755455 ( -0.220842  0.221676 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.60846e-08 ( -1.76778e-08  1.80722e-08 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from   -1.580 sec. to   -0.580 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.239530     ( -3.68771   1.6631 )
Epeak [keV] : 69.2657      ( -23.5319 -69.2666 )
Norm@50keV  : 2.63175E-02    ( -0.0263167   1.64462 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.52 using 59 PHA bins.
# Reduced chi-squared =          1.223 for     56 degrees of freedom 
# Null hypothesis probability =   1.217200e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.720802 ( -0.231041  0.229335 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.30274e-08 ( -1.8038e-08  1.87765e-08 ) ergs/cm2
 
Band function
 
Time interval is from   -1.580 sec. to   -0.580 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -0.239249   ( -0.99155   0.917161 )
beta        : -10.0000    ( 10   20 )
Epeak [keV] : 69.2335      ( -25.534 248.495 )
Norm@50keV   : 2.63355E-02    ( -0.0263355   1.65625 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.52 using 59 PHA bins.
# Reduced chi-squared =          1.246 for     55 degrees of freedom 
# Null hypothesis probability =   1.041090e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.737701 ( 6.2623  -0.24768 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.6639e-08 ( -5.6632e-08  -2.27596e-08 ) ergs/cm2
 
Single BB
 
 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 15.2019  (-4.17595  6.0619)
R^2/D10^2   : 8.57936E-02  (-0.0857847   0.180505)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.48 using 59 PHA bins.
# Reduced chi-squared =          1.219 for     57 degrees of freedom 
# Null hypothesis probability =   1.241720e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.142e-09   2.528e-09
25- 50  1.666e-08   9.813e-09
50-150  2.635e-08   1.651e-08
15-150  4.715e-08   2.828e-08
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 186.000       (-122.069      -185.446)
Norm        : 3.12536       (-0.899337     1.19669)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.20 using 59 PHA bins.
# Reduced chi-squared =          1.214 for     57 degrees of freedom 
# Null hypothesis probability =   1.289995e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.851e-09   4.666e-09
25- 50  1.498e-08   9.065e-09
50-150  3.208e-08   1.903e-08
15-150  5.491e-08   3.316e-08
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 2.64666        (-2.6196      22.107)
R1^2/D10^2  : 41.8584        (-50.2743      -50.2743)
kT2 [keV]   : 16.8272        (-4.94395      -16.8368)
R2^2/D10^2  : 5.66562E-02    (-0.057547   0.141016)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          67.75 using 59 PHA bins.
# Reduced chi-squared =          1.232 for     55 degrees of freedom 
# Null hypothesis probability =   1.160428e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  6.716e-09   4.673e-09
25- 50  1.469e-08   8.955e-09
50-150  2.897e-08   1.875e-08
15-150  5.038e-08   3.008e-08
Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)
Power-law model
 
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.85273     ( -0.243409   0.255446 )
Norm@50keV  : 1.98432E-03    ( -0.000319047   0.000310529 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.91 using 59 PHA bins.
# Reduced chi-squared =          1.086 for     57 degrees of freedom 
# Null hypothesis probability =   3.051781e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.279226 ( -0.0382962  0.0383228 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.51704e-07 ( -1.03128e-07  1.0512e-07 ) ergs/cm2
 
Cutoff power-law model
 
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.69212     ( -0.975154   0.617964 )
Epeak [keV] : 84.7419      ( -84.7195 -84.7409 )
Norm@50keV  : 2.44182E-03    ( -0.0024419   0.00615125 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.80 using 59 PHA bins.
# Reduced chi-squared =          1.104 for     56 degrees of freedom 
# Null hypothesis probability =   2.766341e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.277598 ( -0.039125  0.039092 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.41985e-07 ( -1.15451e-07  1.12343e-07 ) ergs/cm2
 
Band function
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -1.69159   ( -1.88271   0.976414 )
beta        : -10.00000    ( 10   20 )
Epeak [keV] : 84.5992      ( -64.8234 -84.5992 )
Norm@50keV   : 2.44293E-03    ( -0.000331738   0.00614475 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.80 using 59 PHA bins.
# Reduced chi-squared =          1.124 for     55 degrees of freedom 
# Null hypothesis probability =   2.461835e-01
 
Photon flux (15-150 keV)    in 35.72 sec: 0.276522 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 
 S(25-50 keV) vs. S(50-100 keV) plot 
 
S(25-50 keV)  = 1.87e-07
S(50-100 keV) = 2.07e-07
 T90 vs. Hardness ratio plot 
 
T90                                   = 30.7519999146461 sec.
Hardness ratio (energy fluence ratio) = 1.10695
 Color vs. Color plot 
 
Count Ratio  (25-50 keV) / (15-25 keV) = 1.12678
Count Ratio (50-100 keV) / (15-25 keV) = 0.567708
 Mask shadow pattern 
 
IMX = 5.255861683523052E-01, IMY = -4.271340771280909E-01
 TIME vs. PHA plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 TIME vs. DetID plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 100 us light curve (15-350 keV)
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
 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:
-239.368000 -3.404000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.4586 -40.4910    3.0  42.8   34.1   1.5952   3.8    5.0	Vela X-1                      
170.2822 -60.6238    1.0  18.5   -1.0   1.9366  11.6    1.0	Cen X-3                       
186.6555 -62.5882    8.5  14.2  -25.4   0.2421   1.4   10.9	GX 301-2                      
244.9694 -15.6426    0.7  51.8 -157.1   8.4822  16.3    0.6	Sco X-1                       
256.1038 -37.8041    8.1  43.6 -125.9  -0.8284  -1.4    6.1	4U 1700-377                   
256.4443 -36.4238  112.3  44.6 -127.3   0.0624   0.1    0.4	GX 349+2                      
184.3435 -14.3026    2.7  36.5  116.2   1.8993   4.3 ------	UNKNOWN                       
197.0856 -13.5923    2.0  35.9  137.3   1.8929   5.6 ------	UNKNOWN                       
135.4406 -50.6938    3.0  38.0   20.2   1.0212   3.9 ------	UNKNOWN                       
150.6217 -49.2085    3.2  29.3   28.8   0.8085   3.6 ------	UNKNOWN                       
152.9373 -82.4213    2.6  35.4  -34.9   1.0714   4.4 ------	UNKNOWN                       
 54.4135 -70.5819    2.6  56.9  -29.8   4.7886   4.4 ------	UNKNOWN                       
 Pre-slew background subtracted image of 15-350 keV band 
Time interval of the image:
-3.404000 32.312000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.7005 -40.5576    2.7  42.6   34.2   0.6473   4.2    7.8	Vela X-1                      
170.7014 -60.6750    7.6  18.3   -1.4   0.0924   1.5   11.8	Cen X-3                       
186.4241 -62.7042    6.5  14.3  -25.3   0.1025   1.8    7.5	GX 301-2                      
244.9822 -15.6377   67.6  51.8 -157.0   0.0287   0.2    0.2	Sco X-1                       
255.9612 -37.7143   14.4  43.5 -126.1  -0.1482  -0.8    7.9	4U 1700-377                   
256.5894 -36.3316    4.9  44.7 -127.3   0.4903   2.3    9.2	GX 349+2                      
147.5182 -42.3315    1.1  34.1   39.1   1.1218  10.1 ------	UNKNOWN                       
224.9184  -0.0585    2.3  55.1  171.7   1.6494   5.1 ------	UNKNOWN                       
 Post-slew image of 15-350 keV band 
Time interval of the image:
102.932620 463.532600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5040 -40.5747    0.9   9.2   10.3   2.7519  12.8    1.6	Vela X-1                      
170.3347 -60.6406    1.1  22.9 -116.0   2.9030  10.7    1.2	Cen X-3                       
186.6230 -62.6647    4.6  30.5 -121.6   0.8067   2.5    6.4	GX 301-2                      
150.5628 -16.3673    3.1  26.1   99.9   1.4150   3.7 ------	UNKNOWN                       
 66.3653 -58.1219    3.4  50.8  -44.5   4.6415   3.4 ------	UNKNOWN                       
117.8731 -82.2195    2.3  41.0  -80.9   5.0554   5.1 ------	UNKNOWN                       
 72.6462 -68.7927    3.2  45.7  -57.6   4.4650   3.6 ------	UNKNOWN                       
Plot creation:
Sat May 30 17:25:39 EDT 2015