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
280.5124 -28.5362 0.0023 16.2420 175.3411 7.8844535 81.740 TRIG_00458448
Foreground time interval of the image:
-1.056 15.837 (delta_t = 16.893 [sec])
Background time interval of the image:
-239.664 -1.056 (delta_t = 238.608 [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
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)
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 -1.056 sec. to 80.272 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14905 ( -0.0457998 0.0455342 )
Norm@50keV : 7.09590E-03 ( -0.000169968 0.000169442 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.30 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 57 degrees of freedom
# Null hypothesis probability = 4.272711e-01
Photon flux (15-150 keV) in 81.33 sec: 0.827434 ( -0.0213777 0.0215045 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.9427e-06 ( -1.42943e-07 1.43186e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.056 sec. to 80.272 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14397 ( -0.0493256 0.043279 )
Epeak [keV] : 1.00000E+04 ( )
Norm@50keV : 7.13142E-03 ( -0.000170106 0.00016388 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.46 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 56 degrees of freedom
# Null hypothesis probability = 3.853242e-01
Photon flux (15-150 keV) in 81.33 sec: 0.828018 ( -0.022282 0.020549 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.94039e-06 ( -1.39888e-07 1.47874e-07 ) ergs/cm2
Band function
Time interval is from -1.056 sec. to 80.272 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.903468 ( 0.903468 0.903468 )
beta : -1.14905 ( -0.0455357 0.0458064 )
Epeak [keV] : 54.7740 ( -54.774 -54.774 )
Norm@50keV : 1.28092E-02 ( -0.00436861 390006 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.30 using 59 PHA bins.
# Reduced chi-squared = 1.060 for 55 degrees of freedom
# Null hypothesis probability = 3.549542e-01
Photon flux (15-150 keV) in 81.33 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] : 22.0923 ( )
R^2/D10^2 : 2.70022E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 440.23 using 59 PHA bins.
# Reduced chi-squared = 7.7233 for 57 degrees of freedom
# Null hypothesis probability = 1.341303e-60
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.980e-07 9.353e-09
25- 50 1.049e-06 3.945e-08
50-150 3.827e-06 1.269e-07
15-150 5.075e-06 1.322e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 3.58598 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 324.92 using 59 PHA bins.
# Reduced chi-squared = 5.7003 for 57 degrees of freedom
# Null hypothesis probability = 3.644662e-39
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.262e-07 2.009e-08
25- 50 1.397e-06 3.538e-08
50-150 3.064e-06 8.052e-08
15-150 5.187e-06 1.383e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.90452 (-0.878038 0.948635)
R1^2/D10^2 : 0.325290 (-0.0875375 0.130511)
kT2 [keV] : 40.2811 (-4.44709 6.35684)
R2^2/D10^2 : 3.54869E-03 (-0.0012217 0.00152427)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.38 using 59 PHA bins.
# Reduced chi-squared = 1.243 for 55 degrees of freedom
# Null hypothesis probability = 1.062061e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.662e-07 3.973e-08
25- 50 1.260e-06 6.588e-08
50-150 4.275e-06 2.859e-07
15-150 6.001e-06 3.111e-07
Peak spectrum fit
Power-law model
Time interval is from -0.268 sec. to 0.732 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.28770 ( -0.0518138 0.0518352 )
Norm@50keV : 9.21206E-02 ( -0.00270495 0.00270493 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 80.74 using 59 PHA bins.
# Reduced chi-squared = 1.416 for 57 degrees of freedom
# Null hypothesis probability = 2.099325e-02
Photon flux (15-150 keV) in 1 sec: 10.9657 ( -0.338855 0.339284 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.13081e-07 ( -2.90903e-08 2.91396e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.268 sec. to 0.732 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.774481 ( -0.224204 0.214027 )
Epeak [keV] : 135.193 ( -24.7078 54.7844 )
Norm@50keV : 0.156661 ( -0.0303461 0.0395677 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.93 using 59 PHA bins.
# Reduced chi-squared = 1.124 for 56 degrees of freedom
# Null hypothesis probability = 2.445150e-01
Photon flux (15-150 keV) in 1 sec: 10.6678 ( -0.3569 0.3577 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.91332e-07 ( -3.1008e-08 3.0919e-08 ) ergs/cm2
Band function
Time interval is from -0.268 sec. to 0.732 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.774532 ( -0.246729 0.183619 )
beta : -10.0000 ( 10 3.37508e-14 )
Epeak [keV] : 135.184 ( -24.716 54.7636 )
Norm@50keV : 0.156644 ( -0.0303257 0.0396052 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.93 using 59 PHA bins.
# Reduced chi-squared = 1.144 for 55 degrees of freedom
# Null hypothesis probability = 2.161529e-01
Photon flux (15-150 keV) in 1 sec: 10.7004 ( ) 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] : 18.8466 ( )
R^2/D10^2 : 0.603760 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 236.00 using 59 PHA bins.
# Reduced chi-squared = 4.1404 for 57 degrees of freedom
# Null hypothesis probability = 1.215490e-23
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.228e-08 2.495e-09
25- 50 2.022e-07 8.400e-09
50-150 5.269e-07 2.500e-08
15-150 7.713e-07 2.775e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 45.9411 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 148.87 using 59 PHA bins.
# Reduced chi-squared = 2.6117 for 57 degrees of freedom
# Null hypothesis probability = 3.837555e-10
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.144e-07 3.650e-09
25- 50 2.201e-07 6.600e-09
50-150 4.826e-07 1.520e-08
15-150 8.171e-07 2.610e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.62548 (-0.948667 1.0528)
R1^2/D10^2 : 6.39643 (-2.12719 3.57897)
kT2 [keV] : 27.6648 (-2.28385 2.98498)
R2^2/D10^2 : 0.139263 (-0.0433425 0.0518165)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.16 using 59 PHA bins.
# Reduced chi-squared = 1.076 for 55 degrees of freedom
# Null hypothesis probability = 3.263817e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.225e-08 1.040e-08
25- 50 2.084e-07 1.695e-08
50-150 6.024e-07 4.585e-08
15-150 8.930e-07 5.410e-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: 1.12803 ( -0.034338 0.03421 )
Norm@50keV : 3.14206E-02 ( -0.000575844 0.000574218 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.00 using 59 PHA bins.
# Reduced chi-squared = 0.6842 for 57 degrees of freedom
# Null hypothesis probability = 9.672020e-01
Photon flux (15-150 keV) in 16.89 sec: 3.65512 ( -0.0722197 0.07249 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.49989e-06 ( -9.91703e-08 9.92593e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12196 ( -0.0340639 0.0351199 )
Epeak [keV] : 9999.12 ( -9999.2 -9999.2 )
Norm@50keV : 3.15472E-02 ( -0.000566216 0.00213553 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.16 using 59 PHA bins.
# Reduced chi-squared = 0.6993 for 56 degrees of freedom
# Null hypothesis probability = 9.574145e-01
Photon flux (15-150 keV) in 16.89 sec: 3.65315 ( -0.07218 0.07235 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.49972e-06 ( -9.82322e-08 9.94483e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.879610 ( 0.87961 0.87961 )
beta : -1.12803 ( -0.0342159 0.0343372 )
Epeak [keV] : 58.2703 ( -58.2703 -58.2703 )
Norm@50keV : 5.63769E-02 ( -0.017803 1.60756e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.00 using 59 PHA bins.
# Reduced chi-squared = 0.7091 for 55 degrees of freedom
# Null hypothesis probability = 9.494767e-01
Photon flux (15-150 keV) in 16.89 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) = 1.21e-06
S(50-100 keV) = 2.18e-06
T90 vs. Hardness ratio plot
T90 = 40.944000005722 sec.
Hardness ratio (energy fluence ratio) = 1.80165
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.48721
Count Ratio (50-100 keV) / (15-25 keV) = 1.44925
Mask shadow pattern
IMX = -2.903595258416043E-01, IMY = -2.366202735736934E-02
TIME vs. PHA plot around the trigger time
TIME vs. DetID plot around the trigger time
100 us light curve (15-350 keV)
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:
-239.664000 -1.056000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9766 -15.6310 0.6 31.8 -95.1 7.2077 19.5 0.6 Sco X-1
254.4345 35.3287 4.0 52.6 -19.4 1.7830 2.9 1.4 Her X-1
255.9684 -37.8595 807.3 31.9 -142.1 -0.0037 -0.0 1.3 4U 1700-377
256.4998 -36.4576 5.3 30.5 -140.8 0.5477 2.2 3.7 GX 349+2
262.9906 -24.5996 16.2 18.4 -128.8 0.1570 0.7 8.8 GX 1+4
264.7283 -44.4443 13.0 33.8 -158.9 0.2363 0.9 0.7 4U 1735-44
268.2914 -1.4281 3.3 14.4 -36.1 0.7359 3.5 4.8 SW J1753.5-0127
270.3016 -25.0350 2.0 14.3 -147.7 1.2109 5.8 2.8 GX 5-1
270.3886 -25.7601 5.7 14.9 -149.4 0.4180 2.0 4.8 GRS 1758-258
274.0136 -14.0284 3.4 3.8 -109.2 0.7364 3.4 0.7 GX 17+2
275.8237 -30.3268 6.1 17.9 -170.5 0.4013 1.9 5.8 H1820-303
284.9898 -24.7755 28.8 14.1 155.9 0.0813 0.4 9.1 HT1900.1-2455
288.7724 10.7983 3.8 25.8 30.3 0.7820 3.1 9.0 GRS 1915+105
263.0461 -33.8541 5.3 25.1 -146.1 0.5014 2.2 3.1 GX 354-0
277.3681 -23.8388 1.9 11.3 -174.4 1.2874 6.0 ------ UNKNOWN
269.2778 31.4927 2.2 44.7 -5.7 1.9469 5.1 ------ UNKNOWN
273.2590 -69.7151 4.4 57.3 -173.8 2.8269 2.6 ------ UNKNOWN
234.3285 -27.3639 4.3 43.1 -112.4 2.5470 2.7 ------ UNKNOWN
236.3702 -2.6884 2.3 42.0 -75.5 4.3438 5.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.056000 15.836590
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9767 -15.5896 5.9 31.8 -95.0 -0.3169 -2.0 3.0 Sco X-1
254.4988 35.5038 7.2 52.8 -19.2 0.4377 1.6 9.9 Her X-1
255.8744 -37.9731 23.1 32.0 -142.1 0.0556 0.5 9.4 4U 1700-377
256.2652 -36.2933 18.4 30.6 -140.3 -0.0715 -0.6 11.3 GX 349+2
262.9481 -24.6324 5.4 18.4 -128.8 0.2081 2.1 7.6 GX 1+4
264.5936 -44.3800 10.3 33.8 -158.7 0.1345 1.1 7.7 4U 1735-44
268.2484 -1.3126 27.2 14.6 -36.0 -0.0388 -0.4 11.1 SW J1753.5-0127
270.3687 -24.9288 9.1 14.2 -147.7 -0.1112 -1.3 10.1 GX 5-1
270.1411 -25.7648 5.6 15.0 -148.6 -0.1775 -2.1 8.8 GRS 1758-258
274.0815 -13.9368 4.2 3.7 -108.3 0.2587 2.8 7.4 GX 17+2
275.7683 -30.4771 7.2 18.0 -170.4 -0.1502 -1.6 10.5 H1820-303
285.2020 -24.9527 5.2 14.3 155.6 0.2221 2.2 9.2 HT1900.1-2455
288.8517 11.0937 4.6 26.1 30.2 0.2919 2.5 9.4 GRS 1915+105
262.8161 -33.6784 0.0 25.1 -145.5 0.0694 0.7 12.7 GX 354-0
295.5105 7.2767 3.1 26.6 47.3 0.4929 3.6 ------ UNKNOWN
287.0849 -48.9998 2.3 37.3 174.2 0.6641 5.1 ------ UNKNOWN
280.5124 -28.5362 0.1 16.2 175.3 7.8846 81.7 ------ UNKNOWN
265.3173 -64.2480 2.1 52.4 -168.9 1.3731 5.6 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
55.436620 962.436700
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9851 -15.6313 0.4 35.2 -61.9 26.4782 26.2 0.6 Sco X-1
256.0884 -37.7645 2.5 22.3 -106.5 2.7643 4.5 6.8 4U 1700-377
256.4308 -36.4939 2.8 21.7 -103.4 2.4566 4.1 4.3 GX 349+2
262.8681 -24.7451 3.1 16.2 -66.4 2.0775 3.7 7.7 GX 1+4
264.7092 -44.5409 4.1 20.4 -131.8 1.6968 2.9 5.6 4U 1735-44
268.3438 -1.4592 3.8 29.5 -11.1 2.1462 3.1 1.5 SW J1753.5-0127
270.3064 -25.0809 1.3 9.7 -57.4 4.8606 8.7 1.2 GX 5-1
270.2884 -25.8236 4.8 9.5 -61.6 1.3873 2.4 4.9 GRS 1758-258
274.0111 -14.0353 2.6 15.7 -9.7 2.5648 4.4 0.3 GX 17+2
276.0790 -30.2715 5.5 4.2 -101.1 1.2757 2.1 9.8 H1820-303
284.9682 -25.0712 2.7 5.3 64.3 2.4086 4.2 9.8 HT1900.1-2455
288.7477 10.9936 3.6 40.3 26.8 3.4192 3.2 4.1 GRS 1915+105
263.0070 -33.8188 1.9 15.9 -99.6 3.5733 5.9 1.3 GX 354-0
291.2171 -31.9529 2.9 9.9 127.2 2.3364 4.0 ------ UNKNOWN
268.9848 17.6303 3.3 47.5 -0.7 4.0456 3.5 ------ UNKNOWN
255.2337 -41.6679 1.8 24.4 -115.1 4.3051 6.3 ------ UNKNOWN
243.8854 8.0993 2.6 50.9 -35.3 8.4092 4.5 ------ UNKNOWN
215.3373 -71.4919 3.8 55.2 -145.2 12.5677 3.1 ------ UNKNOWN
Plot creation:
Sat May 30 21:55:07 EDT 2015