batgrbproduct analysis for trigger=252588

batgrbproduct Analysis for Trigger=252588

Analysis Summary

Notes:

1) No attempt has been made to eliminate the non-significant decimal places.
2) This batgrbproduct analysis is done using the HEASARC data.
3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time (local time): Wed Jun 24 00:37:32 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger252588
======================================================================

  Trigger: 00252588      Segment: 000

  BAT Trigger Time: 188450933.76   [s; MET]
      Trigger Stop: 188450937.856   [s; MET]
               UTC: 2006-12-22T03:28:52.110840    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 358.243358155449   Dec: 46.5262619462849  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.21
     Image Trigger?:     NO
     Rate S/N Ratio:     13.3790881602597  [ if not an image trigger ]
     Image S/N Ratio:    7.21

  Flight Position:   [ source = BAT ]
    RA: 358.243358155449   Dec: 46.5262619462849  [deg; J2000]

  Ground Position:   [ source = BAT pre-slew burst ]
    RA: 358.237373942495   Dec: 46.5158302015211  [deg; J2000]  
        { 23h 52m 57.0s , +46d 30' 57.0" }
         +/- 1.56229441093894 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.556574715650855 [arcmin] (formal 1-sigma fit error)
    SNR: 16.0810449912385
 
  Angular difference between Flight and Ground position is 0.672901 arcmin
 
  Partial Coding Fraction: 0.703125    [ including projection effects ]

  Duration
     T90: 100 +/- 12.1655250605964
        Measured from: -4.75999999046326
                   to: 95.2400000095367     [s; relative to TRIGTIME]
     T50: 29 +/- 1
        Measured from: 59.2400000095367
                   to: 88.2400000095367     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 86.2400000095367     
                   to: 87.2400000095367     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -98.7599999904633     
                   to: 117.240000009537     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     3.268251   4.724640   4.007228   1.124115
           0.079271   0.083356   0.074353   0.062220 [error]
 Peak      0.160070   0.332253   0.388398   0.125317
           0.007018   0.008908   0.009644   0.006824 [error]

     [ fluence units of on-axis counts / fully illuminated detector ] 

======================================================================
 
=== 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 9.46e-07 1.93e-06 3.06e-06 1.08e-05 8.51e-06 1.68e-05   erg/cm2
              Error 4.56e-08 5.31e-08 7.84e-08 6.66e-07 1.96e-07 6.95e-07   erg/cm2
Peak flux Power-law 1.51e+00 2.19e+00 2.38e+00 4.80e+00 7.56e+00 1.09e+01   ph/cm2/s
              Error 9.35e-02 8.26e-02 7.44e-02 3.28e-01 2.26e-01 3.69e-01   ph/cm2/s
 
Fluence   Cutoff-PL 9.30e-07 1.93e-06 3.08e-06 1.00e-05 8.48e-06 1.60e-05   erg/cm2
              Error 5.24e-08 5.54e-08 8.88e-08 1.50e-06 2.13e-07 1.54e-06   erg/cm2
Peak flux Cutoff-PL 1.35e+00 2.23e+00 2.50e+00 3.30e+00 7.45e+00 9.38e+00   ph/cm2/s
              Error 1.20e-01 8.81e-02 9.69e-02 6.26e-01 2.32e-01 6.60e-01   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    1.331    0.043    -      -           4.02e-03 8.89e-05   50.380 57
CPL   1.276    0.111     707.6    0.0      4.24e-03 5.49e-04   50.490 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    0.886    0.051    -      -           6.59e-02 1.96e-03   66.980 57
CPL   0.487    0.212     225.8  113.9      9.78e-02 2.02e-02   55.710 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

 
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
 
T90 in the 50-300 keV band: 66.944000 sec.
T50 in the 50-300 keV band: 15.360000 sec.

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100  216.000  -98.760  117.240
T90   100.000   -4.760   95.240
T50    29.000   59.240   88.240
Peak    1.000   86.240   87.240

Click here for the BAT GCN circular template

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
  358.2374    46.5158   0.0119    28.0611  -136.1159         2.4645439     16.081 TRIG_00252588                 
 
Foreground time interval of the image:
-98.760  37.141 (delta_t = 135.901 [sec])
Background time interval of the image:
-239.760 -98.760 (delta_t = 141.000 [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 4.096000

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 4.096000

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 4.096000

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  -98.760 sec. to  117.240 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.33102     ( -0.0429588   0.0428468 )
Norm@50keV  : 4.01615E-03    ( -8.8938e-05   8.8881e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.38 using 59 PHA bins.
# Reduced chi-squared =         0.8838 for     57 degrees of freedom 
# Null hypothesis probability =   7.199914e-01
 
Photon flux (15-150 keV)    in 216 sec: 0.481983 ( -0.0118886  0.0119416 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.50932e-06 ( -1.96135e-07  1.96448e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from  -98.760 sec. to  117.240 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.27606     ( -0.164086   0.0579131 )
Epeak [keV] : 707.619      ( -999.999 -999.999 )
Norm@50keV  : 4.24441E-03    ( -0.000405913   0.000693029 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.49 using 59 PHA bins.
# Reduced chi-squared =         0.9015 for     56 degrees of freedom 
# Null hypothesis probability =   6.828220e-01
 
Photon flux (15-150 keV)    in 216 sec: 0.479143 0.481549 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.48375e-06 ( -2.03731e-07  2.22934e-07 ) ergs/cm2

Band function

Time interval is from  -98.760 sec. to  117.240 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 0.143292   ( 0.590331   0.590331 )
beta        : -1.34514    ( 1.34307   0.0475033 )
Epeak [keV] : 37.2111      ( -37.1942 129.913 )
Norm@50keV   : 4.77396E-02    ( -0.0480207   237.752 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          48.98 using 59 PHA bins.
# Reduced chi-squared =         0.8905 for     55 degrees of freedom 
# Null hypothesis probability =   7.028564e-01
 
Photon flux (15-150 keV)    in 216 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]    : 19.1574  (  )
R^2/D10^2   : 2.36829E-02  (   )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =         468.12 using 59 PHA bins.
# Reduced chi-squared =         8.2126 for     57 degrees of freedom 
# Null hypothesis probability =   6.327533e-66
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  3.679e-07   1.717e-08
25- 50  1.780e-06   6.037e-08
50-150  4.808e-06   1.825e-07
15-150  6.956e-06   1.901e-07

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 199.363       (      )
Norm        : 2.04216       (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         154.61 using 59 PHA bins.
# Reduced chi-squared =         2.7124 for     57 degrees of freedom 
# Null hypothesis probability =   6.033581e-11
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.098e-06   2.700e-08
25- 50  2.113e-06   5.216e-08
50-150  4.634e-06   1.123e-07
15-150  7.845e-06   1.858e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 8.21402        (-0.716951      0.762553)
R1^2/D10^2  : 0.262442        (-0.0655563      0.0946589)
kT2 [keV]   : 33.4896        (-3.00605      3.93971)
R2^2/D10^2  : 3.09523E-03    (-0.00093296   0.00114699)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.00 using 59 PHA bins.
# Reduced chi-squared =          1.036 for     55 degrees of freedom 
# Null hypothesis probability =   4.004958e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.142e-07   7.171e-08
25- 50  1.995e-06   9.515e-08
50-150  5.668e-06   3.586e-07
15-150  8.477e-06   4.612e-07

Peak spectrum fit

Power-law model

Time interval is from   86.240 sec. to   87.240 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.885543     ( -0.0512418   0.050904 )
Norm@50keV  : 6.58759E-02    ( -0.00196551   0.0019629 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.98 using 59 PHA bins.
# Reduced chi-squared =          1.175 for     57 degrees of freedom 
# Null hypothesis probability =   1.718401e-01
 
Photon flux (15-150 keV)    in 1 sec: 7.56049 ( -0.225553  0.225624 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.4349e-07 ( -2.38954e-08  2.39383e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   86.240 sec. to   87.240 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.486807     ( -0.217108   0.206964 )
Epeak [keV] : 225.828      ( -58.4934 169.317 )
Norm@50keV  : 9.78267E-02    ( -0.017713   0.0226399 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          55.71 using 59 PHA bins.
# Reduced chi-squared =         0.9948 for     56 degrees of freedom 
# Null hypothesis probability =   4.858729e-01
 
Photon flux (15-150 keV)    in 1 sec: 7.45422 ( -0.23145  0.23158 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.33022e-07 ( -2.5081e-08  2.4951e-08 ) ergs/cm2

Band function

Time interval is from   86.240 sec. to   87.240 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 4.99996   ( -5.45013e-06   -4.99996 )
beta        : -0.946810    ( -0.0579147   0.0574538 )
Epeak [keV] : 31.1162      ( -7.28789 3.48924 )
Norm@50keV   : 1145.20    ( -33.3237   4113.52 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.43 using 59 PHA bins.
# Reduced chi-squared =          1.117 for     55 degrees of freedom 
# Null hypothesis probability =   2.565915e-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]    : 23.8289  (  )
R^2/D10^2   : 0.220259  (   )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =         192.22 using 59 PHA bins.
# Reduced chi-squared =         3.3724 for     57 degrees of freedom 
# Null hypothesis probability =   1.481584e-16
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.227e-08   1.375e-09
25- 50  1.232e-07   5.300e-09
50-150  5.216e-07   2.380e-08
15-150  6.671e-07   2.355e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 199.363       (      )
Norm        : 29.6330       (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         499.34 using 59 PHA bins.
# Reduced chi-squared =         8.7603 for     57 degrees of freedom 
# Null hypothesis probability =   6.162861e-72
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.379e-08   2.455e-09
25- 50  1.419e-07   4.550e-09
50-150  3.113e-07   1.105e-08
15-150  5.270e-07   1.750e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 9.67918        (-1.38431      1.56127)
R1^2/D10^2  : 1.64840        (-0.526354      0.880011)
kT2 [keV]   : 37.4162        (-4.29815      6.57689)
R2^2/D10^2  : 4.76622E-02    (-0.018716   0.0228293)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.11 using 59 PHA bins.
# Reduced chi-squared =         0.9475 for     55 degrees of freedom 
# Null hypothesis probability =   5.856516e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.011e-08   5.985e-09
25- 50  1.341e-07   1.170e-08
50-150  5.646e-07   5.390e-08
15-150  7.388e-07   8.100e-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: 1.57034     ( -0.14492   0.14634 )
Norm@50keV  : 1.20104E-03    ( -0.000100604   9.98041e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          65.22 using 59 PHA bins.
# Reduced chi-squared =          1.144 for     57 degrees of freedom 
# Null hypothesis probability =   2.126729e-01
 
Photon flux (15-150 keV)    in 135.9 sec: 0.152955 ( -0.0123741  0.0123929 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.53227e-06 ( -1.39355e-07  1.40678e-07 ) ergs/cm2

Cutoff power-law model

Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.57325     ( -0.149295   0.143973 )
Epeak [keV] : 9999.36      ( -9999.36 -9999.36 )
Norm@50keV  : 1.20137E-03    ( -0.000668533   0.000826351 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          65.23 using 59 PHA bins.
# Reduced chi-squared =          1.165 for     56 degrees of freedom 
# Null hypothesis probability =   1.866675e-01
 
Photon flux (15-150 keV)    in 135.9 sec: 0.153005 ( -0.01212  0.012288 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.53129e-06 ( -7.2326e-08  1.39298e-07 ) ergs/cm2

Band function

 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -0.530363   ( 1.08615   6.08081 )
beta        : -1.60187    ( 1.59459   0.163494 )
Epeak [keV] : 35.9862      ( -36.4247 435.744 )
Norm@50keV   : 7.02824E-03    ( -0.00734324   164.238 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.93 using 59 PHA bins.
# Reduced chi-squared =          1.181 for     55 degrees of freedom 
# Null hypothesis probability =   1.690160e-01
 
Photon flux (15-150 keV)    in 135.9 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)  = 1.93e-06
S(50-100 keV) = 3.06e-06

T90 vs. Hardness ratio plot

T90                                   = 100 sec.
Hardness ratio (energy fluence ratio) = 1.58549

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.44562
Count Ratio (50-100 keV) / (15-25 keV) = 1.22611

Mask shadow pattern

IMX = -3.842128353345811E-01, IMY = 3.695306085312690E-01

TIME vs. PHA plot around the trigger time

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000

TIME vs. DetID plot around the trigger time

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000

100 us light curve (15-350 keV)

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000

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:
-239.760000 -98.760000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
  1.8210  11.5445    2.2  57.0 -167.4   2.0990   5.2 ------	UNKNOWN                       
355.4036  26.3389    3.3  46.0 -152.5   0.6926   3.5 ------	UNKNOWN                       
253.9772  68.0956    3.0  48.4  -50.0   1.7795   3.9 ------	UNKNOWN

Pre-slew background subtracted image of 15-350 keV band

Time interval of the image:
-98.760000 37.140590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 13.6422  15.2657    2.2  49.8 -179.5   1.5380   5.2 ------	UNKNOWN                       
358.2374  46.5158    0.7  28.1 -136.1   2.4644  16.1 ------	UNKNOWN                       
351.0864  33.1836    2.3  42.0 -142.8   1.2329   5.0 ------	UNKNOWN                       
350.5586  20.1603    2.9  53.5 -151.1   1.9174   3.9 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
89.940590 482.303700
540.240000 962.293000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
308.0810  41.1625   27.9  35.9  -62.0  -0.3053  -0.4   12.7	Cyg X-3                       
326.1993  38.2788    4.7  24.8  -79.9   1.3884   2.5    2.9	Cyg X-2                       
248.8050  75.8802    3.5  49.6    0.3   2.6925   3.3 ------	UNKNOWN                       
358.2439  46.4906    1.7   0.0 -177.1   2.5645   6.8 ------	UNKNOWN                       
343.0783  -5.7543    3.8  54.0 -143.3   7.8668   3.1 ------	UNKNOWN

Plot creation:
Wed Jun 24 01:05:06 EDT 2015