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
326.1377 -19.9812 0.0049 36.2023 -87.3746 5.8497357 39.716 TRIG_00309111
Foreground time interval of the image:
-1.264 10.736 (delta_t = 12.000 [sec])
Background time interval of the image:
-239.264 -1.264 (delta_t = 238.000 [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 -1.264 sec. to 10.736 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74235 ( -0.0578771 0.0582662 )
Norm@50keV : 3.02944E-02 ( -0.000994771 0.000993314 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.65 using 59 PHA bins.
# Reduced chi-squared = 1.064 for 57 degrees of freedom
# Null hypothesis probability = 3.457020e-01
Photon flux (15-150 keV) in 12 sec: 4.08484 ( -0.142733 0.143128 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.35598e-06 ( -1.13177e-07 1.13336e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.264 sec. to 10.736 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.23049 ( -0.255165 0.241379 )
Epeak [keV] : 77.6500 ( -10.8138 24.4011 )
Norm@50keV : 5.37364E-02 ( -0.0124412 0.0173336 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.76 using 59 PHA bins.
# Reduced chi-squared = 0.8351 for 56 degrees of freedom
# Null hypothesis probability = 8.056769e-01
Photon flux (15-150 keV) in 12 sec: 3.95029 ( -0.15385 0.15444 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.24845e-06 ( -1.24884e-07 1.24488e-07 ) ergs/cm2
Band function
Time interval is from -1.264 sec. to 10.736 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.23046 ( -0.194797 0.275667 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 77.6349 ( -8.88593 24.398 )
Norm@50keV : 5.37319E-02 ( -0.012459 0.0173387 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.76 using 59 PHA bins.
# Reduced chi-squared = 0.8502 for 55 degrees of freedom
# Null hypothesis probability = 7.775658e-01
Photon flux (15-150 keV) in 12 sec: 3.96128 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.24724e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 14.0830 ( )
R^2/D10^2 : 0.538940 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 230.56 using 59 PHA bins.
# Reduced chi-squared = 4.0449 for 57 degrees of freedom
# Null hypothesis probability = 9.800181e-23
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.708e-07 1.698e-08
25- 50 1.013e-06 4.464e-08
50-150 1.327e-06 8.460e-08
15-150 2.611e-06 9.540e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 132.344 (-19.4074 18.7488)
Norm : 16.7867 (-0.68429 0.895985)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.15 using 59 PHA bins.
# Reduced chi-squared = 0.8272 for 57 degrees of freedom
# Null hypothesis probability = 8.207291e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.221e-07 3.294e-08
25- 50 9.494e-07 4.974e-08
50-150 1.775e-06 4.182e-07
15-150 3.246e-06 4.446e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.04794 (-0.848059 0.904613)
R1^2/D10^2 : 4.26877 (-1.41126 2.42657)
kT2 [keV] : 23.4132 (-2.44539 3.30373)
R2^2/D10^2 : 6.24247E-02 (-0.0255952 0.035627)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.38 using 59 PHA bins.
# Reduced chi-squared = 0.9160 for 55 degrees of freedom
# Null hypothesis probability = 6.515351e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.854e-07 6.108e-08
25- 50 9.755e-07 7.164e-08
50-150 1.751e-06 1.866e-07
15-150 3.212e-06 2.868e-07
Peak spectrum fit
Power-law model
Time interval is from -0.264 sec. to 0.736 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.45409 ( -0.062544 0.062711 )
Norm@50keV : 0.149995 ( -0.0056302 0.00562872 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.08 using 59 PHA bins.
# Reduced chi-squared = 0.9838 for 57 degrees of freedom
# Null hypothesis probability = 5.096617e-01
Photon flux (15-150 keV) in 1 sec: 18.5036 ( -0.728542 0.729487 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.43426e-06 ( -5.75444e-08 5.76295e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.264 sec. to 0.736 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.944134 ( -0.27794 0.261523 )
Epeak [keV] : 111.346 ( -21.8444 59.333 )
Norm@50keV : 0.262904 ( -0.064304 0.0914711 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.41 using 59 PHA bins.
# Reduced chi-squared = 0.7931 for 56 degrees of freedom
# Null hypothesis probability = 8.679898e-01
Photon flux (15-150 keV) in 1 sec: 18.1249 ( -0.7503 0.7514 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40331e-06 ( 0 0 ) ergs/cm2
Band function
Time interval is from -0.264 sec. to 0.736 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.456623 ( -0.575884 1.40939 )
beta : -1.71911 ( -0.31149 0.158863 )
Epeak [keV] : 68.8177 ( -24.1883 44.1727 )
Norm@50keV : 0.511826 ( -0.310274 4.41902 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.03 using 59 PHA bins.
# Reduced chi-squared = 0.7461 for 55 degrees of freedom
# Null hypothesis probability = 9.191851e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.39887e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 16.2475 ( )
R^2/D10^2 : 1.64300 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 171.91 using 59 PHA bins.
# Reduced chi-squared = 3.0160 for 57 degrees of freedom
# Null hypothesis probability = 1.851474e-13
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.936e-08 6.790e-09
25- 50 3.810e-07 1.890e-08
50-150 7.070e-07 4.940e-08
15-150 1.177e-06 5.100e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 76.8969 (-2.87541 2.87538)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.04 using 59 PHA bins.
# Reduced chi-squared = 0.9831 for 57 degrees of freedom
# Null hypothesis probability = 5.111964e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.915e-07 7.600e-09
25- 50 3.684e-07 1.545e-08
50-150 8.080e-07 3.170e-08
15-150 1.368e-06 5.650e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.08644 (-1.25543 1.28115)
R1^2/D10^2 : 7.87808 (-2.43976 4.26461)
kT2 [keV] : 31.5212 (-5.12451 8.62596)
R2^2/D10^2 : 0.117602 (-0.0664555 0.111341)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.64 using 59 PHA bins.
# Reduced chi-squared = 0.8116 for 55 degrees of freedom
# Null hypothesis probability = 8.396835e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.450e-07 1.925e-08
25- 50 3.860e-07 3.370e-08
50-150 8.743e-07 1.581e-07
15-150 1.405e-06 2.045e-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: 1.74235 ( -0.0578771 0.0582662 )
Norm@50keV : 3.02944E-02 ( -0.000994771 0.000993314 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.65 using 59 PHA bins.
# Reduced chi-squared = 1.064 for 57 degrees of freedom
# Null hypothesis probability = 3.457020e-01
Photon flux (15-150 keV) in 12 sec: 4.08484 ( -0.142733 0.143128 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.35598e-06 ( -1.13177e-07 1.13336e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.23049 ( -0.255165 0.241379 )
Epeak [keV] : 77.6500 ( -10.8138 24.4011 )
Norm@50keV : 5.37364E-02 ( -0.0124412 0.0173336 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.76 using 59 PHA bins.
# Reduced chi-squared = 0.8351 for 56 degrees of freedom
# Null hypothesis probability = 8.056769e-01
Photon flux (15-150 keV) in 12 sec: 3.95029 ( -0.15385 0.15444 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.24845e-06 ( -1.24884e-07 1.24488e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.23046 ( -0.194797 0.275667 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 77.6349 ( -8.88593 24.398 )
Norm@50keV : 5.37319E-02 ( -0.012459 0.0173387 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.76 using 59 PHA bins.
# Reduced chi-squared = 0.8502 for 55 degrees of freedom
# Null hypothesis probability = 7.775658e-01
Photon flux (15-150 keV) in 12 sec: 3.96128 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.24724e-06 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 9.24e-07
S(50-100 keV) = 1.10e-06
T90 vs. Hardness ratio plot
T90 = 8 sec.
Hardness ratio (energy fluence ratio) = 1.19048
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.35318
Count Ratio (50-100 keV) / (15-25 keV) = 0.934469
Mask shadow pattern
IMX = 3.352746678764664E-02, IMY = 7.311830148425137E-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:
-239.264000 -1.264000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
256.0707 -37.8202 3.0 28.0 67.0 1.0963 3.9 4.2 4U 1700-377
256.4110 -36.5572 16.7 27.5 69.6 0.1905 0.7 8.1 GX 349+2
262.8753 -24.6195 13.1 22.1 98.6 -0.1963 -0.9 10.5 GX 1+4
264.6343 -44.5812 13.0 24.8 47.2 0.1898 0.9 9.1 4U 1735-44
268.3866 -1.4521 96.8 31.9 148.4 0.0356 0.1 1.1 SW J1753.5-0127
270.2052 -25.1391 3.6 15.5 101.8 0.6421 3.3 5.6 GX 5-1
270.1680 -25.7087 3.8 15.4 99.6 0.6789 3.5 7.6 GRS 1758-258
274.0714 -14.0951 2.1 18.3 141.4 1.1172 5.6 5.2 GX 17+2
275.9409 -30.3590 2.9 10.3 78.4 0.7014 4.0 1.0 H1820-303
285.0505 -24.8819 7.2 3.4 150.0 0.2886 1.6 2.4 HT1900.1-2455
288.7303 10.9281 24.9 38.6 -171.5 0.1252 0.5 4.1 GRS 1915+105
262.8888 -33.8865 2.8 21.8 73.7 0.8928 4.1 5.9 GX 354-0
245.3322 -16.6748 2.1 40.2 103.1 4.1587 5.6 ------ UNKNOWN
266.7949 -27.3594 1.0 18.2 92.5 2.3747 11.5 ------ UNKNOWN
277.3015 -23.7981 2.2 9.8 117.3 0.9191 5.3 ------ UNKNOWN
289.3230 -34.9450 3.2 7.5 -6.6 0.6534 3.6 ------ UNKNOWN
285.2097 0.7171 2.8 28.5 -178.1 0.8319 4.1 ------ UNKNOWN
285.2400 7.4263 2.7 35.2 -177.3 0.9780 4.3 ------ UNKNOWN
314.0114 -17.8759 4.4 26.4 -99.8 0.7314 2.7 ------ UNKNOWN
305.8002 18.3594 3.7 49.4 -150.4 1.6621 3.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.264000 10.736000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
256.1670 -37.8791 8.4 27.9 66.8 -0.0757 -1.4 8.8 4U 1700-377
256.2620 -36.3547 6.4 27.6 70.0 0.1006 1.8 9.3 GX 349+2
262.9156 -24.6001 9.0 22.1 98.7 0.0655 1.3 10.1 GX 1+4
264.7739 -44.4433 276.3 24.6 47.3 -0.0020 -0.0 1.4 4U 1735-44
268.4954 -1.5856 0.0 31.7 148.4 0.0759 1.3 11.0 SW J1753.5-0127
270.1467 -24.9804 5.5 15.6 102.3 0.0895 2.1 9.5 GX 5-1
270.3080 -25.7883 7.8 15.3 99.4 0.0643 1.5 2.7 GRS 1758-258
274.1558 -14.1762 0.0 18.2 141.4 -0.0585 -1.3 12.1 GX 17+2
275.7513 -30.3724 6.5 10.4 78.5 0.0772 1.8 9.0 H1820-303
284.9368 -25.0793 71.9 3.3 146.6 -0.0075 -0.2 10.9 HT1900.1-2455
288.8770 11.1017 5.6 38.8 -171.3 0.1341 2.1 10.4 GRS 1915+105
263.1756 -33.7775 6.9 21.6 73.8 0.0801 1.7 9.9 GX 354-0
263.9918 -1.6597 2.3 34.3 141.6 0.2778 4.9 ------ UNKNOWN
291.5600 -79.6949 2.2 52.1 5.3 0.6455 5.3 ------ UNKNOWN
280.9647 1.9966 2.8 30.3 173.6 0.2064 4.2 ------ UNKNOWN
349.9949 -76.2738 4.0 56.8 -8.3 0.5476 2.9 ------ UNKNOWN
326.1377 -19.9812 0.3 36.2 -87.4 5.8495 39.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
115.636600 962.858700
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
285.1504 -25.0116 4.8 38.0 97.4 5.2975 2.4 8.3 HT1900.1-2455
288.8384 10.9627 5.1 48.0 149.6 -6.2690 -2.3 2.6 GRS 1915+105
326.1763 38.3543 6.8 58.3 -157.2 9.0739 1.7 2.0 Cyg X-2
285.3955 -41.6945 2.8 40.6 71.2 11.2977 4.2 ------ UNKNOWN
319.5066 -52.9888 3.9 33.4 30.0 2.5495 2.9 ------ UNKNOWN
342.5763 4.9687 3.0 29.7 -122.6 3.2562 3.8 ------ UNKNOWN
348.1593 -4.5351 5.5 26.4 -100.1 1.8290 2.1 ------ UNKNOWN
353.7782 -4.1908 2.4 31.2 -94.0 5.1509 4.9 449.8 UNKNOWN
357.1323 -8.5063 2.7 32.1 -83.7 4.8008 4.2 538.4 UNKNOWN
352.6198 16.4467 2.7 44.8 -119.8 12.7147 4.2 ------ UNKNOWN
Plot creation:
Sun May 31 07:48:02 EDT 2015