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
145.1488 -21.9538 0.0032 25.2554 -62.4924 3.2401347 59.796 TRIG_00234905
Foreground time interval of the image:
-0.008 10.517 (delta_t = 10.525 [sec])
Background time interval of the image:
-239.184 -0.008 (delta_t = 239.176 [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 1.024000
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 1.024000
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 1.024000
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) 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 -0.008 sec. to 64.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.28250 ( -0.0616236 0.0613626 )
Norm@50keV : 4.67405E-03 ( -0.000150323 0.000150272 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.54 using 59 PHA bins.
# Reduced chi-squared = 0.7113 for 57 degrees of freedom
# Null hypothesis probability = 9.512246e-01
Photon flux (15-150 keV) in 64.97 sec: 0.555869 ( -0.0192672 0.0193362 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.01386e-06 ( -1.04143e-07 1.04463e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.008 sec. to 64.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.27847 ( -0.205453 0.0639197 )
Epeak [keV] : 1.00000E+04 ( )
Norm@50keV : 4.69397E-03 ( -0.000150534 0.000150497 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.56 using 59 PHA bins.
# Reduced chi-squared = 0.7244 for 56 degrees of freedom
# Null hypothesis probability = 9.399984e-01
Photon flux (15-150 keV) in 64.97 sec: 0.555897 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.00471e-06 ( -1.04615e-07 1.21747e-07 ) ergs/cm2
Band function
Time interval is from -0.008 sec. to 64.960 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.762081 ( 0.835711 0.835711 )
beta : -1.30160 ( -0.0857315 0.0745329 )
Epeak [keV] : 72.7665 ( -72.1681 509.158 )
Norm@50keV : 1.03142E-02 ( -0.00597158 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.05 using 59 PHA bins.
# Reduced chi-squared = 0.7283 for 55 degrees of freedom
# Null hypothesis probability = 9.350223e-01
Photon flux (15-150 keV) in 64.97 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] : 19.1471 ( )
R^2/D10^2 : 2.78556E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 259.08 using 59 PHA bins.
# Reduced chi-squared = 4.5453 for 57 degrees of freedom
# Null hypothesis probability = 1.501663e-27
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.301e-07 9.161e-09
25- 50 6.289e-07 3.037e-08
50-150 1.697e-06 9.063e-08
15-150 2.456e-06 1.098e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 2.34197 (-0.0761053 0.0760662)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 106.76 using 59 PHA bins.
# Reduced chi-squared = 1.8730 for 57 degrees of freedom
# Null hypothesis probability = 7.249761e-05
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.790e-07 1.410e-08
25- 50 7.291e-07 2.631e-08
50-150 1.599e-06 5.295e-08
15-150 2.707e-06 9.453e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.99743 (-0.899319 0.990041)
R1^2/D10^2 : 0.334534 (-0.104799 0.165886)
kT2 [keV] : 34.4956 (-4.19371 6.09137)
R2^2/D10^2 : 3.44013E-03 (-0.00135261 0.00180183)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.43 using 59 PHA bins.
# Reduced chi-squared = 0.7533 for 55 degrees of freedom
# Null hypothesis probability = 9.120377e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.894e-07 3.343e-08
25- 50 6.870e-07 5.139e-08
50-150 2.059e-06 2.560e-07
15-150 3.035e-06 2.729e-07
Peak spectrum fit
Power-law model
Time interval is from 2.436 sec. to 3.436 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.13396 ( -0.0777252 0.0773161 )
Norm@50keV : 5.25598E-02 ( -0.00216087 0.00216066 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.95 using 59 PHA bins.
# Reduced chi-squared = 1.210 for 57 degrees of freedom
# Null hypothesis probability = 1.332620e-01
Photon flux (15-150 keV) in 1 sec: 6.11820 ( -0.258571 0.258988 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.43717e-07 ( -2.53849e-08 2.54772e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.436 sec. to 3.436 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12936 ( -0.084169 0.0736371 )
Epeak [keV] : 1.00000E+04 ( )
Norm@50keV : 5.28306E-02 ( -0.00217071 0.00217067 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.06 using 59 PHA bins.
# Reduced chi-squared = 1.233 for 56 degrees of freedom
# Null hypothesis probability = 1.128818e-01
Photon flux (15-150 keV) in 1 sec: 6.11709 ( -0.25714 0.25766 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.4251e-07 ( -2.4238e-08 2.6926e-08 ) ergs/cm2
Band function
Time interval is from 2.436 sec. to 3.436 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.438624 ( 0.75685 0.75685 )
beta : -1.15735 ( -0.112776 0.0879181 )
Epeak [keV] : 65.2490 ( -64.4069 257.938 )
Norm@50keV : 0.156738 ( -0.160288 2.60952e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.51 using 59 PHA bins.
# Reduced chi-squared = 1.246 for 55 degrees of freedom
# Null hypothesis probability = 1.041460e-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] : 19.6072 ( )
R^2/D10^2 : 0.294936 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 233.65 using 59 PHA bins.
# Reduced chi-squared = 4.0992 for 57 degrees of freedom
# Null hypothesis probability = 2.996282e-23
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.203e-08 1.915e-09
25- 50 1.083e-07 6.350e-09
50-150 3.077e-07 2.510e-08
15-150 4.380e-07 2.195e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 25.0878 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 154.65 using 59 PHA bins.
# Reduced chi-squared = 2.7131 for 57 degrees of freedom
# Null hypothesis probability = 5.959242e-11
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.247e-08 2.910e-09
25- 50 1.202e-07 5.950e-09
50-150 2.636e-07 1.165e-08
15-150 4.462e-07 2.130e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.20589 (-1.08492 1.18502)
R1^2/D10^2 : 2.42847 (-0.742905 1.15582)
kT2 [keV] : 52.7428 (-11.8289 25.9353)
R2^2/D10^2 : 1.32664E-02 (-0.00787433 0.0127313)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.08 using 59 PHA bins.
# Reduced chi-squared = 1.074 for 55 degrees of freedom
# Null hypothesis probability = 3.287432e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.439e-08 6.090e-09
25- 50 1.175e-07 1.324e-08
50-150 3.997e-07 1.022e-07
15-150 5.615e-07 1.280e-07
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: 1.23261 ( -0.0519733 0.0517895 )
Norm@50keV : 2.00728E-02 ( -0.000543703 0.000543301 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.94 using 59 PHA bins.
# Reduced chi-squared = 0.6657 for 57 degrees of freedom
# Null hypothesis probability = 9.755940e-01
Photon flux (15-150 keV) in 10.52 sec: 2.36752 ( -0.0689731 0.0692009 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.12316e-06 ( -6.13436e-08 6.14926e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.22791 ( -0.0520599 0.0524207 )
Epeak [keV] : 9997.82 ( -9998.43 -9998.43 )
Norm@50keV : 2.01635E-02 ( -0.000541845 0.00257995 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.01 using 59 PHA bins.
# Reduced chi-squared = 0.6787 for 56 degrees of freedom
# Null hypothesis probability = 9.686809e-01
Photon flux (15-150 keV) in 10.52 sec: 2.36641 ( -0.06894 0.06909 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.12325e-06 ( -6.09844e-08 6.03743e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.812390 ( 0.810375 0.810375 )
beta : -1.24807 ( -0.0705289 0.0629228 )
Epeak [keV] : 88.9960 ( -87.7435 317.162 )
Norm@50keV : 3.75744E-02 ( -0.0172811 1.22176e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.50 using 59 PHA bins.
# Reduced chi-squared = 0.6818 for 55 degrees of freedom
# Null hypothesis probability = 9.657994e-01
Photon flux (15-150 keV) in 10.52 sec: ( ) 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) = 6.64e-07
S(50-100 keV) = 1.09e-06
T90 vs. Hardness ratio plot
T90 = 47.8200000226498 sec.
Hardness ratio (energy fluence ratio) = 1.64157
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.49209
Count Ratio (50-100 keV) / (15-25 keV) = 1.31737
Mask shadow pattern
IMX = 2.178837436603384E-01, IMY = 4.184145176900618E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
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:
-239.184000 -0.008000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5473 -40.5872 2.0 36.7 -28.9 1.2856 5.7 2.1 Vela X-1
105.0356 38.0284 2.4 47.1 141.0 3.0331 4.8 ------ UNKNOWN
131.2591 30.1155 2.8 35.5 171.5 0.9342 4.1 ------ UNKNOWN
127.2232 -8.3913 2.2 3.7 -38.3 0.7700 5.2 ------ UNKNOWN
131.8146 -49.9963 2.6 45.3 -21.9 1.2771 4.4 ------ UNKNOWN
126.5022 -57.7968 3.0 52.8 -17.0 1.6571 3.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.008000 10.516600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5160 -40.5553 69.1 36.6 -28.9 0.0103 0.2 0.6 Vela X-1
87.1007 4.4126 2.9 39.8 86.4 0.5699 4.0 ------ UNKNOWN
110.5557 25.1555 2.9 33.6 137.9 0.2683 4.0 ------ UNKNOWN
148.6634 31.9211 2.6 42.8 -167.6 0.2751 4.4 ------ UNKNOWN
145.1488 -21.9538 0.2 25.3 -62.5 3.2402 59.8 ------ UNKNOWN
164.7017 -20.5178 2.2 40.8 -80.6 0.8808 5.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
58.916600 542.916000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5425 -40.5077 2.5 20.3 21.7 4.2401 4.6 2.9 Vela X-1
170.4896 -60.4762 6.2 42.4 -17.9 2.6432 1.9 10.2 Cen X-3
186.6266 -62.7617 1.1 49.4 -23.2 19.1577 10.3 1.0 GX 301-2
114.0665 -9.9792 2.5 32.1 107.2 7.9698 4.7 ------ UNKNOWN
103.2579 -69.9906 3.0 54.0 16.7 18.3723 3.9 ------ UNKNOWN
146.9080 29.4270 2.8 51.4 -177.7 9.7350 4.2 ------ UNKNOWN
173.9144 -63.0864 2.9 45.5 -17.5 6.3786 4.0 ------ UNKNOWN
161.2866 1.1403 2.7 28.0 -143.3 4.0455 4.3 ------ UNKNOWN
Plot creation:
Sun May 31 11:41:53 EDT 2015