]> git.uio.no Git - u/mrichter/AliRoot.git/blame - TEvtGen/EvtGenModels/EvtBtoXsgammaKagan.cpp
git://git.uio.no / u / mrichter / AliRoot.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
ATO-78 - Technical changes to compare different calibrations
[u/mrichter/AliRoot.git] / TEvtGen / EvtGenModels / EvtBtoXsgammaKagan.cpp
CommitLineData
da0e9ce3 1//--------------------------------------------------------------------------
2//
3// Environment:
4// This software is part of the EvtGen package developed jointly
5// for the BaBar and CLEO collaborations. If you use all or part
6// of it, please give an appropriate acknowledgement.
7//
8// Module: EvtBtoXsgammaKagan.cc
9//
10// Description:
11// Routine to perform two-body non-resonant B->Xs,gamma decays.
12// The X_s mass spectrum generated is based on the Kagan-Neubert model.
13// See hep-ph/9805303 for the model details and input parameters.
14//
15// The input parameters are 1:fermi_model, 2:mB, 3:mb, 4:mu, 5:lam1,
16// 6:delta, 7:z, 8:nIntervalS, 9:nIntervalmH. Choosing fermi_model=1
17// uses an exponential shape function, fermi_model=2 uses a gaussian
18// shape function and fermi_model=3 a roman shape function. The complete mass
19// spectrum for a given set of input parameters is calculated from
20// scratch in bins of nIntervalmH. The s22, s27 and s28 coefficients are calculated
21// in bins of nIntervalS. As the program includes lots of integration, the
22// theoretical hadronic mass spectra is computed for the first time
23// the init method is called. Then, all the other times (eg if we want to decay a B0
24// as well as an anti-B0) the vector mass info stored the first time is used again.
25//
26// Modification history:
27//
28// Jane Tinslay, Francesca Di Lodovico March 21, 2001 Module created
29//------------------------------------------------------------------------
30//
31#include "EvtGenBase/EvtPatches.hh"
32
33#include <stdlib.h>
34#include "EvtGenModels/EvtBtoXsgamma.hh"
35#include "EvtGenBase/EvtRandom.hh"
36#include "EvtGenModels/EvtBtoXsgammaKagan.hh"
37#include <string>
38#include "EvtGenBase/EvtConst.hh"
39#include "EvtGenBase/EvtParticle.hh"
40#include "EvtGenBase/EvtGenKine.hh"
41#include "EvtGenBase/EvtPDL.hh"
42#include "EvtGenBase/EvtReport.hh"
43#include "EvtGenModels/EvtItgSimpsonIntegrator.hh"
44#include "EvtGenModels/EvtItgFunction.hh"
45#include "EvtGenModels/EvtItgPtrFunction.hh"
46#include "EvtGenModels/EvtItgTwoCoeffFcn.hh"
47#include "EvtGenModels/EvtItgThreeCoeffFcn.hh"
48#include "EvtGenModels/EvtItgFourCoeffFcn.hh"
49#include "EvtGenModels/EvtItgAbsIntegrator.hh"
50#include "EvtGenModels/EvtBtoXsgammaFermiUtil.hh"
51
52#include <fstream>
53using std::endl;
54using std::fstream;
55
56bool EvtBtoXsgammaKagan::bbprod = false;
57double EvtBtoXsgammaKagan::intervalMH = 0;
58
59EvtBtoXsgammaKagan::~EvtBtoXsgammaKagan(){
60 delete [] massHad;
61 delete [] brHad;
62}
63
64void EvtBtoXsgammaKagan::init(int nArg, double* args){
65
66 if ((nArg) > 12 || (nArg > 1 && nArg <10) || nArg == 11){
67
68 report(ERROR,"EvtGen") << "EvtBtoXsgamma generator model "
69 << "EvtBtoXsgammaKagan expected "
70 << "either 1(default config) or "
71 << "10 (default mass range) or "
72 << "12 (user range) arguments but found: "
73 <<nArg<<endl;
74 report(ERROR,"EvtGen") << "Will terminate execution!"<<endl;
75 ::abort();
76 }
77
78 if(nArg == 1){
79 bbprod = true;
80 getDefaultHadronicMass();
81 }else{
82 bbprod = false;
83 computeHadronicMass(nArg, args);
84 }
85
86 double mHminLimit=0.6373;
87 double mHmaxLimit=4.5;
88
89 if (nArg>10){
90 _mHmin = args[10];
91 _mHmax = args[11];
92 if (_mHmin > _mHmax){
93 report(ERROR,"EvtGen") << "Minimum hadronic mass exceeds maximum "
94 << endl;
95 report(ERROR,"EvtGen") << "Will terminate execution!" << endl;
96 ::abort();
97 }
98 if (_mHmin < mHminLimit){
99 report(ERROR,"EvtGen") << "Minimum hadronic mass below K pi threshold"
100 << endl;
101 report(ERROR,"EvtGen") << "Resetting to K pi threshold" << endl;
102 _mHmin = mHminLimit;
103 }
104 if (_mHmax > mHmaxLimit){
105 report(ERROR,"EvtGen") << "Maximum hadronic mass above 4.5 GeV/c^2"
106 << endl;
107 report(ERROR,"EvtGen") << "Resetting to 4.5 GeV/c^2" << endl;
108 _mHmax = mHmaxLimit;
109 }
110 }else{
111 _mHmin=mHminLimit; // usually just above K pi threshold for Xsd/u
112 _mHmax=mHmaxLimit;
113 }
114
115}
116
117void EvtBtoXsgammaKagan::getDefaultHadronicMass(){
118
119 massHad = new double[81];
120 brHad = new double[81];
121
122 double mass[81] = { 0, 0.0625995, 0.125199, 0.187798, 0.250398, 0.312997, 0.375597, 0.438196, 0.500796, 0.563395, 0.625995, 0.688594, 0.751194, 0.813793, 0.876392, 0.938992, 1.00159, 1.06419, 1.12679, 1.18939, 1.25199, 1.31459, 1.37719, 1.43979, 1.50239, 1.56499, 1.62759, 1.69019, 1.75278, 1.81538, 1.87798, 1.94058, 2.00318, 2.06578, 2.12838, 2.19098, 2.25358, 2.31618, 2.37878, 2.44138, 2.50398, 2.56658, 2.62918, 2.69178, 2.75438, 2.81698, 2.87958, 2.94217, 3.00477, 3.06737, 3.12997, 3.19257, 3.25517, 3.31777, 3.38037, 3.44297, 3.50557, 3.56817, 3.63077, 3.69337, 3.75597, 3.81857, 3.88117, 3.94377, 4.00637, 4.06896, 4.13156, 4.19416, 4.25676, 4.31936, 4.38196, 4.44456, 4.50716, 4.56976, 4.63236, 4.69496, 4.75756, 4.82016, 4.88276, 4.94536, 5.00796};
123
124 double br[81] = { 0, 1.03244e-09, 3.0239e-08, 1.99815e-07, 7.29392e-07, 1.93129e-06, 4.17806e-06, 7.86021e-06, 1.33421e-05, 2.09196e-05, 3.07815e-05, 4.29854e-05, 5.74406e-05, 7.3906e-05, 9.2003e-05, 0.000111223, 0.000130977, 0.000150618, 0.000169483, 0.000186934, 0.000202392, 0.000215366, 0.000225491, 0.000232496, 0.000236274, 0.000236835, 0.000234313, 0.000228942, 0.000221042, 0.000210994, 0.000199215, 0.000186137, 0.000172194, 0.000157775, 0.000143255, 0.000128952, 0.000115133, 0.000102012, 8.97451e-05, 7.84384e-05, 6.81519e-05, 5.89048e-05, 5.06851e-05, 4.34515e-05, 3.71506e-05, 3.1702e-05, 2.70124e-05, 2.30588e-05, 1.96951e-05, 1.68596e-05, 1.44909e-05, 1.25102e-05, 1.08596e-05, 9.48476e-06, 8.34013e-06, 7.38477e-06, 6.58627e-06, 5.91541e-06, 5.35022e-06, 4.87047e-06, 4.46249e-06, 4.11032e-06, 3.80543e-06, 3.54051e-06, 3.30967e-06, 3.10848e-06, 2.93254e-06, 2.78369e-06, 2.65823e-06, 2.55747e-06, 2.51068e-06, 2.57179e-06, 2.74684e-06, 3.02719e-06, 3.41182e-06, 3.91387e-06, 4.56248e-06, 5.40862e-06, 6.53915e-06, 8.10867e-06, 1.04167e-05 };
125
126 for(int i=0; i<81; i++){
127 massHad[i] = mass[i];
128 brHad[i] = br[i];
129 }
130 intervalMH=80;
131}
132
133void EvtBtoXsgammaKagan::computeHadronicMass(int /*nArg*/, double* args){
134
135 //Input parameters
136 int fermiFunction = (int)args[1];
137 _mB = args[2];
138 _mb = args[3];
139 _mu = args[4];
140 _lam1 = args[5];
141 _delta = args[6];
142 _z = args[7];
143 _nIntervalS = args[8];
144 _nIntervalmH = args[9];
145 std::vector<double> mHVect(int(_nIntervalmH+1.0));
146 massHad = new double[int(_nIntervalmH+1.0)];
147 brHad = new double[int(_nIntervalmH+1.0)];
148 intervalMH=_nIntervalmH;
149
150 //Going to have to add a new entry into the data file - takes ages...
151 report(WARNING,"EvtGen") << "EvtBtoXsgammaKagan: calculating new hadronic mass spectra. This takes a while..." << endl;
152
153 //Now need to compute the mHVect vector for
154 //the current parameters
155
156 //A few more parameters
157 double _mubar = _mu;
158 _mW = 80.33;
159 _mt = 175.0;
160 _alpha = 1./137.036;
161 _lambdabar = _mB - _mb;
162 _kappabar = 3.382 - 4.14*(sqrt(_z) - 0.29);
163 _fz=Fz(_z);
164 _rer8 = (44./9.) - (8./27.)*pow(EvtConst::pi,2.);
165 _r7 = (-10./3.) - (8./9.)*pow(EvtConst::pi,2.);
166 _rer2 = -4.092 + 12.78*(sqrt(_z) -.29);
167 _gam77 = 32./3.;
168 _gam27 = 416./81.;
169 _gam87 = -32./9.;
170 _lam2 = .12;
171 _beta0 = 23./3.;
172 _beta1 = 116./3.;
173 _alphasmZ = .118;
174 _mZ = 91.187;
175 _ms = _mb/50.;
176
177 double eGammaMin = 0.5*_mB*(1. - _delta);
178 double eGammaMax = 0.5*_mB;
179 double yMin = 2.*eGammaMin/_mB;
180 double yMax = 2.*eGammaMax/_mB;
181 double _CKMrat= 0.976;
182 double Nsl = 1.0;
183
184 //Calculate alpha the various scales
185 _alphasmW = CalcAlphaS(_mW);
186 _alphasmt = CalcAlphaS(_mt);
187 _alphasmu = CalcAlphaS(_mu);
188 _alphasmubar = CalcAlphaS(_mubar);
189
190 //Calculate the Wilson Coefficients and Delta
191 _etamu = _alphasmW/_alphasmu;
192 _kSLemmu = (12./23.)*((1./_etamu) -1.);
193 CalcWilsonCoeffs();
194 CalcDelta();
195
196 //Build s22 and s27 vector - saves time because double
197 //integration is required otherwise
198 std::vector<double> s22Coeffs(int(_nIntervalS+1.0));
199 std::vector<double> s27Coeffs(int(_nIntervalS+1.0));
200 std::vector<double> s28Coeffs(int(_nIntervalS+1.0));
201
202 double dy = (yMax - yMin)/_nIntervalS;
203 double yp = yMin;
204
205 std::vector<double> sCoeffs(1);
206 sCoeffs[0] = _z;
207
208 //Define s22 and s27 functions
209 EvtItgPtrFunction *mys22Func = new EvtItgPtrFunction(&s22Func, 0., yMax+0.1, sCoeffs);
210 EvtItgPtrFunction *mys27Func = new EvtItgPtrFunction(&s27Func, 0., yMax+0.1, sCoeffs);
211
212 //Use a simpson integrator
213 EvtItgAbsIntegrator *mys22Simp = new EvtItgSimpsonIntegrator(*mys22Func, 1.0e-4, 20);
214 EvtItgAbsIntegrator *mys27Simp = new EvtItgSimpsonIntegrator(*mys27Func, 1.0e-4, 50);
215
216 int i;
217
218 for (i=0;i<int(_nIntervalS+1.0);i++) {
219
220 s22Coeffs[i] = (16./27.)*mys22Simp->evaluate(1.0e-20,yp);
221 s27Coeffs[i] = (-8./9.)*_z*mys27Simp->evaluate(1.0e-20,yp);
222 s28Coeffs[i] = -s27Coeffs[i]/3.;
223 yp = yp + dy;
224
225 }
226
227 delete mys22Func;
228 delete mys27Func;
229 delete mys22Simp;
230 delete mys27Simp;
231
232 //Define functions and vectors used to calculate mHVect. Each function takes a set
233 //of vectors which are used as the function coefficients
234 std::vector<double> FermiCoeffs(6);
235 std::vector<double> varCoeffs(3);
236 std::vector<double> DeltaCoeffs(1);
237 std::vector<double> s88Coeffs(2);
238 std::vector<double> sInitCoeffs(3);
239
240 varCoeffs[0] = _mB;
241 varCoeffs[1] = _mb;
242 varCoeffs[2] = 0.;
243
244 DeltaCoeffs[0] = _alphasmu;
245
246 s88Coeffs[0] = _mb;
247 s88Coeffs[1] = _ms;
248
249 sInitCoeffs[0] = _nIntervalS;
250 sInitCoeffs[1] = yMin;
251 sInitCoeffs[2] = yMax;
252
253 FermiCoeffs[0]=fermiFunction;
254 FermiCoeffs[1]=0.0;
255 FermiCoeffs[2]=0.0;
256 FermiCoeffs[3]=0.0;
257 FermiCoeffs[4]=0.0;
258 FermiCoeffs[5]=0.0;
259
260 //Coefficients for gamma function
261 std::vector<double> gammaCoeffs(6);
262 gammaCoeffs[0]=76.18009172947146;
263 gammaCoeffs[1]=-86.50532032941677;
264 gammaCoeffs[2]=24.01409824083091;
265 gammaCoeffs[3]=-1.231739572450155;
266 gammaCoeffs[4]=0.1208650973866179e-2;
267 gammaCoeffs[5]=-0.5395239384953e-5;
268
269 //Calculate quantities for the fermi function to be used
270 //Distinguish among the different shape functions
271 if (fermiFunction == 1) {
272
273 FermiCoeffs[1]=_lambdabar;
274 FermiCoeffs[2]=(-3.*pow(_lambdabar,2.)/_lam1) - 1.;
275 FermiCoeffs[3]=_lam1;
276 FermiCoeffs[4]=1.0;
277
278 EvtItgPtrFunction *myNormFunc = new EvtItgPtrFunction(&EvtBtoXsgammaFermiUtil::FermiExpFunc, -_mb, _mB-_mb, FermiCoeffs);
279 EvtItgAbsIntegrator *myNormSimp = new EvtItgSimpsonIntegrator(*myNormFunc, 1.0e-4, 40);
280 FermiCoeffs[4]=myNormSimp->normalisation();
281 delete myNormFunc; myNormFunc=0;
282 delete myNormSimp; myNormSimp=0;
283
284 } else if (fermiFunction == 2) {
285
286 double a = EvtBtoXsgammaFermiUtil::FermiGaussFuncRoot(_lambdabar, _lam1, _mb, gammaCoeffs);
287 FermiCoeffs[1]=_lambdabar;
288 FermiCoeffs[2]=a;
289 FermiCoeffs[3]= EvtBtoXsgammaFermiUtil::Gamma((2.0 + a)/2., gammaCoeffs)/
290 EvtBtoXsgammaFermiUtil::Gamma((1.0 + a)/2., gammaCoeffs);
291 FermiCoeffs[4]=1.0;
292
293 EvtItgPtrFunction *myNormFunc = new EvtItgPtrFunction(&EvtBtoXsgammaFermiUtil::FermiGaussFunc, -_mb, _mB-_mb, FermiCoeffs);
294 EvtItgAbsIntegrator *myNormSimp = new EvtItgSimpsonIntegrator(*myNormFunc, 1.0e-4, 40);
295 FermiCoeffs[4]=myNormSimp->normalisation();
296 delete myNormFunc; myNormFunc=0;
297 delete myNormSimp; myNormSimp=0;
298
299 }
300 else if (fermiFunction == 3) {
301
302 double rho = EvtBtoXsgammaFermiUtil::FermiRomanFuncRoot(_lambdabar, _lam1);
303 FermiCoeffs[1]=_mB;
304 FermiCoeffs[2]=_mb;
305 FermiCoeffs[3]= rho;
306 FermiCoeffs[4]=_lambdabar;
307 FermiCoeffs[5]=1.0;
308
309 EvtItgPtrFunction *myNormFunc = new EvtItgPtrFunction(&EvtBtoXsgammaFermiUtil::FermiRomanFunc, -_mb, _mB-_mb, FermiCoeffs);
310 EvtItgAbsIntegrator *myNormSimp = new EvtItgSimpsonIntegrator(*myNormFunc, 1.0e-4, 40);
311 FermiCoeffs[5]=myNormSimp->normalisation();
312 delete myNormFunc; myNormFunc=0;
313 delete myNormSimp; myNormSimp=0;
314
315 }
316
317 //Define functions
318 EvtItgThreeCoeffFcn* myDeltaFermiFunc = new EvtItgThreeCoeffFcn(&DeltaFermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs, DeltaCoeffs);
319 EvtItgThreeCoeffFcn* mys88FermiFunc = new EvtItgThreeCoeffFcn(&s88FermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs, s88Coeffs);
320 EvtItgTwoCoeffFcn* mys77FermiFunc = new EvtItgTwoCoeffFcn(&s77FermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs);
321 EvtItgTwoCoeffFcn* mys78FermiFunc = new EvtItgTwoCoeffFcn(&s78FermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs);
322 EvtItgFourCoeffFcn* mys22FermiFunc = new EvtItgFourCoeffFcn(&sFermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs, sInitCoeffs, s22Coeffs);
323 EvtItgFourCoeffFcn* mys27FermiFunc = new EvtItgFourCoeffFcn(&sFermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs, sInitCoeffs, s27Coeffs);
324 EvtItgFourCoeffFcn* mys28FermiFunc = new EvtItgFourCoeffFcn(&sFermiFunc, -_mb, _mB-_mb, FermiCoeffs, varCoeffs, sInitCoeffs, s28Coeffs);
325
326 //Define integrators
327 EvtItgSimpsonIntegrator* myDeltaFermiSimp =
328 new EvtItgSimpsonIntegrator(*myDeltaFermiFunc, 1.0e-4, 40);
329 EvtItgSimpsonIntegrator* mys77FermiSimp =
330 new EvtItgSimpsonIntegrator(*mys77FermiFunc, 1.0e-4, 40);
331 EvtItgSimpsonIntegrator* mys88FermiSimp =
332 new EvtItgSimpsonIntegrator(*mys88FermiFunc, 1.0e-4, 40);
333 EvtItgSimpsonIntegrator* mys78FermiSimp =
334 new EvtItgSimpsonIntegrator(*mys78FermiFunc, 1.0e-4, 40);
335 EvtItgSimpsonIntegrator* mys22FermiSimp =
336 new EvtItgSimpsonIntegrator(*mys22FermiFunc, 1.0e-4, 40);
337 EvtItgSimpsonIntegrator* mys27FermiSimp =
338 new EvtItgSimpsonIntegrator(*mys27FermiFunc, 1.0e-4, 40);
339 EvtItgSimpsonIntegrator* mys28FermiSimp =
340 new EvtItgSimpsonIntegrator(*mys28FermiFunc, 1.0e-4, 40);
341
342 //Finally calculate mHVect for the range of hadronic masses
343 double mHmin = sqrt(_mB*_mB - 2.*_mB*eGammaMax);
344 double mHmax = sqrt(_mB*_mB - 2.*_mB*eGammaMin);
345 double dmH = (mHmax - mHmin)/_nIntervalmH;
346
347 double mH=mHmin;
348
349 //Calculating the Branching Fractions
350 for (i=0;i<int(_nIntervalmH+1.0);i++) {
351
352 double ymH = 1. - ((mH*mH)/(_mB*_mB));
353
354 //Need to set ymH as one of the input parameters
355 myDeltaFermiFunc->setCoeff(2, 2, ymH);
356 mys77FermiFunc->setCoeff(2, 2, ymH);
357 mys88FermiFunc->setCoeff(2, 2, ymH);
358 mys78FermiFunc->setCoeff(2, 2, ymH);
359 mys22FermiFunc->setCoeff(2, 2, ymH);
360 mys27FermiFunc->setCoeff(2, 2, ymH);
361 mys28FermiFunc->setCoeff(2, 2, ymH);
362
363 //Integrate
364
365 double deltaResult = myDeltaFermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
366 double s77Result = mys77FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
367 double s88Result = mys88FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
368 double s78Result = mys78FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
369 double s22Result = mys22FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
370 double s27Result = mys27FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
371 mys28FermiSimp->evaluate((_mB*ymH-_mb),_mB-_mb);
372
373 double py = (pow(_CKMrat,2.)*(6./_fz)*(_alpha/EvtConst::pi)*(deltaResult*_cDeltatot + (_alphasmu/EvtConst::pi)*(s77Result*pow(_c70mu,2.) + s27Result*_c2mu*(_c70mu - _c80mu/3.) + s78Result*_c70mu*_c80mu + s22Result*_c2mu*_c2mu + s88Result*_c80mu*_c80mu ) ) );
374
375 mHVect[i] = 2.*(mH/(_mB*_mB))*0.105*Nsl*py;
376
377 massHad[i] = mH;
378 brHad[i] = 2.*(mH/(_mB*_mB))*0.105*Nsl*py;
379
380 mH = mH+dmH;
381
382 }
383
384 //Clean up
385 delete myDeltaFermiFunc; myDeltaFermiFunc=0;
386 delete mys88FermiFunc; mys88FermiFunc=0;
387 delete mys77FermiFunc; mys77FermiFunc=0;
388 delete mys78FermiFunc; mys78FermiFunc=0;
389 delete mys22FermiFunc; mys22FermiFunc=0;
390 delete mys27FermiFunc; mys27FermiFunc=0;
391 delete mys28FermiFunc; mys28FermiFunc=0;
392
393 delete myDeltaFermiSimp; myDeltaFermiSimp=0;
394 delete mys77FermiSimp; mys77FermiSimp=0;
395 delete mys88FermiSimp; mys88FermiSimp=0;
396 delete mys78FermiSimp; mys78FermiSimp=0;
397 delete mys22FermiSimp; mys22FermiSimp=0;
398 delete mys27FermiSimp; mys27FermiSimp=0;
399 delete mys28FermiSimp; mys28FermiSimp=0;
400
401}
402
403double EvtBtoXsgammaKagan::GetMass( int /*Xscode*/ ){
404
405// Get hadronic mass for the event according to the hadronic mass spectra computed in computeHadronicMass
406 double mass=0.0;
407 double min=_mHmin;
408 if(bbprod)min=1.1;
409 // double max=4.5;
410 double max=_mHmax;
411 double xbox(0), ybox(0);
412 double boxheight(0);
413 double trueHeight(0);
414 double boxwidth=max-min;
415 double wgt(0.);
416
417 for (int i=0;i<int(intervalMH+1.0);i++) {
418 if(brHad[i]>boxheight)boxheight=brHad[i];
419 }
420 while ((mass > max) || (mass < min)){
421 xbox = EvtRandom::Flat(boxwidth)+min;
422 ybox=EvtRandom::Flat(boxheight);
423 trueHeight=0.0;
424 // Correction by Peter Richardson
425 for( int i = 1 ; i < int( intervalMH + 1.0 ) ; ++i ) {
426 if ( ( massHad[i] >= xbox ) && ( 0.0 == trueHeight ) ) {
427 wgt=(xbox-massHad[i-1])/(massHad[i]-massHad[i-1]);
428 trueHeight=brHad[i-1]+wgt*(brHad[i]-brHad[i-1]);
429 }
430 }
431
432 if (ybox>trueHeight) {
433 mass=0.0;
434 } else {
435 mass=xbox;
436 }
437 }
438
439 return mass;
440}
441
442double EvtBtoXsgammaKagan::CalcAlphaS(double scale) {
443
444 double v = 1. -_beta0*(_alphasmZ/(2.*EvtConst::pi))*(log(_mZ/scale));
445 return (_alphasmZ/v)*(1. - ((_beta1/_beta0)*(_alphasmZ/(4.*EvtConst::pi))*(log(v)/v)));
446
447}
448
449void EvtBtoXsgammaKagan::CalcWilsonCoeffs( ){
450
451 double mtatmw=_mt*pow((_alphasmW/_alphasmt),(12./23.))*(1 + (12./23.)*((253./18.) - (116./23.))*((_alphasmW - _alphasmt)/(4.0*EvtConst::pi)) - (4./3.)*(_alphasmt/EvtConst::pi));
452 double xt=pow(mtatmw,2.)/pow(_mW,2.);
453
454
455
456 /////LO
457 _c2mu = .5*pow(_etamu,(-12./23.)) + .5*pow(_etamu,(6./23.));
458
459 double c7mWsm = ((3.*pow(xt,3.) - 2.*pow(xt,2.))/(4.*pow((xt - 1.),4.)))*log(xt)
460 + ((-8.*pow(xt,3.) - 5.*pow(xt,2.) + 7.*xt)/(24.*pow((xt - 1.),3.) )) ;
461
462 double c8mWsm = ((-3.*pow(xt,2.))/(4.*pow((xt - 1.),4.)))*log(xt)
463 + ((- pow(xt,3.) + 5.*pow(xt,2.) + 2.*xt)/(8.*pow((xt - 1.),3.)));
464
465 double c7constmu = (626126./272277.)*pow(_etamu,(14./23.))
466 - (56281./51730.)*pow(_etamu,(16./23.)) - (3./7.)*pow(_etamu,(6./23.))
467 - (1./14.)*pow(_etamu,(-12./23.)) - .6494*pow(_etamu,.4086) - .038*pow(_etamu,-.423)
468 - .0186*pow(_etamu,-.8994) - .0057*pow(_etamu,.1456);
469
470 _c70mu = c7mWsm*pow(_etamu,(16./23.)) + (8./3.)*(pow(_etamu,(14./23.))
471 -pow(_etamu,(16./23.)))*c8mWsm + c7constmu;
472
473 double c8constmu = (313063./363036.)*pow(_etamu,(14./23.))
474 -.9135*pow(_etamu,.4086) + .0873*pow(_etamu,-.423) - .0571*pow(_etamu,-.8994)
475 + .0209*pow(_etamu,.1456);
476
477 _c80mu = c8mWsm*pow(_etamu,(14./23.)) + c8constmu;
478
479 //Compute the dilogarithm (PolyLog(2,x)) with the Simpson integrator
480 //The dilogarithm is defined as: Li_2(x)=Int_0^x(-log(1.-z)/z)
481 //however, Mathematica implements it as Sum[z^k/k^2,{k,1,Infinity}], so, althought the two
482 //results are similar and both implemented in the program, we prefer to use the
483 //one closer to the Mathematica implementation as identical to what used by the theorists.
484
485 // EvtItgFunction *myDiLogFunc = new EvtItgFunction(&diLogFunc, 0., 1.-1./xt);
486 //EvtItgAbsIntegrator *myDiLogSimp = new EvtItgSimpsonIntegrator(*myDiLogFunc, 1.0e-4, 50);
487 //double li2 = myDiLogSimp->evaluate(1.0e-20,1.-1./xt);
488
489 double li2=diLogMathematica(1.-1./xt);
490
491double c7mWsm1 = ( (-16. *pow(xt,4.) -122. *pow(xt,3.) + 80. *pow(xt,2.) -8. *xt)/
492(9. *pow((xt -1.),4.)) * li2 +
493(6. *pow(xt,4.) + 46. *pow(xt,3.) -28. *pow(xt,2.))/(3. *pow((xt-1.),5.)) *pow(log(xt),2.)
494+ (-102. *pow(xt,5.) -588. *pow(xt,4.) -2262. *pow(xt,3.) + 3244. *pow(xt,2.) -1364. *xt
495+ 208.)/(81. *pow((xt-1),5.)) *log(xt)
496+ (1646. *pow(xt,4.) + 12205. *pow(xt,3.) -10740. *pow(xt,2.) + 2509. *xt -436.)/
497(486. *pow((xt-1),4.)) );
498
499double c8mWsm1 = ((-4. *pow(xt,4.) + 40. *pow(xt,3.) + 41. *pow(xt,2.) + xt)/
500(6. *pow((xt-1.),4.)) * li2
501+ (-17. *pow(xt,3.) -31. *pow(xt,2.))/(2. *pow((xt-1.),5.) ) *pow(log(xt),2.)
502+ (-210. *pow(xt,5.) + 1086. *pow(xt,4.) + 4893. *pow(xt,3.) + 2857. *pow(xt,2.)
503-1994. *xt + 280.)/(216. *pow((xt-1),5.)) *log(xt)
504+ (737. *pow(xt,4.) -14102. *pow(xt,3.) -28209. *pow(xt,2.) + 610. *xt -508.)/
505(1296. *pow((xt-1),4.)) );
506
507double E1 = (xt *(18. -11. *xt -pow(xt,2.))/(12.*pow( (1. -xt),3.))
508+ pow(xt,2.)* (15. -16. *xt + 4. *pow(xt,2.))/(6. *pow((1. -xt),4.)) *log(xt)
509-2./3. *log(xt) );
510
511double e1 = 4661194./816831.;
512double e2 = -8516./2217. ;
513double e3 = 0.;
514double e4 = 0.;
515double e5 = -1.9043;
516double e6 = -.1008;
517double e7 = .1216;
518double e8 = .0183;
519
520double f1 = -17.3023;
521double f2 = 8.5027;
522double f3 = 4.5508;
523double f4 = .7519;
524double f5 = 2.004;
525double f6 = .7476;
526double f7 = -.5385;
527double f8 = .0914;
528
529double g1 = 14.8088;
530double g2 = -10.809;
531double g3 = -.874;
532double g4 = .4218;
533double g5 = -2.9347;
534double g6 = .3971;
535double g7 = .1600;
536double g8 = .0225;
537
538
539double c71constmu = ((e1 *_etamu *E1 + f1 + g1 *_etamu) *pow(_etamu,(14./23.))
540+ (e2 *_etamu *E1 + f2 + g2 *_etamu) *pow(_etamu,(16./23.))
541+ (e3 *_etamu *E1 + f3 + g3 *_etamu) *pow(_etamu,(6./23.))
542+ (e4 *_etamu *E1 + f4 + g4 *_etamu) *pow(_etamu,(-12./23.))
543+ (e5 *_etamu *E1 + f5 + g5 *_etamu) *pow(_etamu,.4086)
544+ (e6 *_etamu *E1 + f6 + g6 *_etamu) *pow(_etamu,(-.423))
545+ (e7 *_etamu *E1 + f7 + g7 *_etamu) *pow(_etamu,(-.8994))
546+ (e8 *_etamu *E1 + f8 + g8 *_etamu) *pow(_etamu,.1456 ));
547
548double c71pmu = ( ((297664./14283. *pow(_etamu,(16./23.))
549-7164416./357075. *pow(_etamu,(14./23.))
550+ 256868./14283. *pow(_etamu,(37./23.)) - 6698884./357075. *pow(_etamu,(39./23.)))
551*(c8mWsm))
552+ 37208./4761. *(pow(_etamu,(39./23.)) - pow(_etamu,(16./23.))) *(c7mWsm)
553+ c71constmu );
554
555_c71mu = (_alphasmW/_alphasmu *(pow(_etamu,(16./23.))* c7mWsm1 + 8./3. *(pow(_etamu,(14./23.))
556- pow(_etamu,(16./23.)) ) *c8mWsm1 ) + c71pmu);
557
558_c7emmu = ((32./75. *pow(_etamu,(-9./23.)) - 40./69. *pow(_etamu,(-7./23.)) +
559 88./575. *pow(_etamu,(16./23.))) *c7mWsm + (-32./575. *pow(_etamu,(-9./23.)) +
560 32./1449. *pow(_etamu,(-7./23.)) + 640./1449.*pow(_etamu,(14./23.)) -
561 704./1725.*pow(_etamu,(16./23.)) ) *c8mWsm
562 - 190./8073.*pow(_etamu,(-35./23.)) - 359./3105. *pow(_etamu,(-17./23.)) +
563 4276./121095. *pow(_etamu,(-12./23.)) + 350531./1009125.*pow(_etamu,(-9./23.))
564 + 2./4347. *pow(_etamu,(-7./23.)) - 5956./15525. *pow(_etamu,(6./23.)) +
565 38380./169533. *pow(_etamu,(14./23.)) - 748./8625. *pow(_etamu,(16./23.)));
566
567// Wilson coefficients values as according to Kagan's program
568// _c2mu=1.10566;
569//_c70mu=-0.314292;
570// _c80mu=-0.148954;
571// _c71mu=0.480964;
572// _c7emmu=0.0323219;
573
574}
575
576void EvtBtoXsgammaKagan::CalcDelta() {
577
578 double cDelta77 = (1. + (_alphasmu/(2.*EvtConst::pi)) *(_r7 - (16./3.) + _gam77*log(_mb/_mu)) + ( (pow((1. - _z),4.)/_fz) - 1.)*(6.*_lam2/pow(_mb,2.)) + (_alphasmubar/(2.*EvtConst::pi))*_kappabar )*pow(_c70mu,2.);
579
580 double cDelta27 = ((_alphasmu/(2.*EvtConst::pi))*(_rer2 + _gam27*log(_mb/_mu)) - (_lam2/(9.*_z*pow(_mb,2.))))*_c2mu*_c70mu;
581
582 double cDelta78 = (_alphasmu/(2.*EvtConst::pi))*(_rer8 + _gam87*log(_mb/_mu))*_c70mu*_c80mu;
583
584 _cDeltatot = cDelta77 + cDelta27 + cDelta78 + (_alphasmu/(2.*EvtConst::pi))*_c71mu*_c70mu + (_alpha/_alphasmu)*(2.*_c7emmu*_c70mu - _kSLemmu*pow(_c70mu,2.));
585
586}
587
588double EvtBtoXsgammaKagan::Delta(double y, double alphasMu) {
589
590 //Fix for singularity at endpoint
591 if (y >= 1.0) y = 0.9999999999;
592
593 return ( - 4.*(alphasMu/(3.*EvtConst::pi*(1. - y)))*(log(1. - y) + 7./4.)*
594 exp(-2.*(alphasMu/(3.*EvtConst::pi))*(pow(log(1. - y),2) + (7./2.)*log(1. - y))));
595
596}
597
598double EvtBtoXsgammaKagan::s77(double y) {
599
600 //Fix for singularity at endpoint
601 if (y >= 1.0) y = 0.9999999999;
602
603 return ((1./3.)*(7. + y - 2.*pow(y,2) - 2.*(1. + y)*log(1. - y)));
604}
605
606double EvtBtoXsgammaKagan::s88(double y, double mb, double ms) {
607
608 //Fix for singularity at endpoint
609 if (y >= 1.0) y = 0.9999999999;
610
611 return ((1./27.)*((2.*(2. - 2.*y + pow(y,2))/y)*(log(1. - y) + 2.*log(mb/ms))
612 - 2.*pow(y,2) - y - 8.*((1. - y)/y)));
613}
614
615double EvtBtoXsgammaKagan::s78(double y) {
616
617 //Fix for singularity at endpoint
618 if (y >= 1.0) y = 0.9999999999;
619
620 return ((8./9.)*(((1. - y)/y)*log(1. - y) + 1. + (pow(y,2)/4.)));
621}
622
623double EvtBtoXsgammaKagan::ReG(double y) {
624
625 if (y < 4.) return -2.*pow(atan(sqrt(y/(4. - y))),2.);
626 else {
627 return 2.*(pow(log((sqrt(y) + sqrt(y - 4.))/2.),2.)) - (1./2.)*pow(EvtConst::pi,2.);
628 }
629
630}
631
632double EvtBtoXsgammaKagan::ImG(double y) {
633
634 if (y < 4.) return 0.0;
635 else {
636 return (-2.*EvtConst::pi*log((sqrt(y) + sqrt(y - 4.))/2.));
637 }
638}
639
640double EvtBtoXsgammaKagan::s22Func(double y, const std::vector<double> &coeffs) {
641
642 //coeffs[0]=z
643 return (1. - y)*((pow(coeffs[0],2.)/pow(y,2.))*(pow(ReG(y/coeffs[0]),2.) + pow(ImG(y/coeffs[0]),2.)) + (coeffs[0]/y)*ReG(y/coeffs[0]) + (1./4.));
644
645}
646
647double EvtBtoXsgammaKagan::s27Func(double y, const std::vector<double> &coeffs) {
648
649 //coeffs[0] = z
650 return (ReG(y/coeffs[0]) + y/(2.*coeffs[0]));
651
652}
653
654double EvtBtoXsgammaKagan::DeltaFermiFunc(double y, const std::vector<double> &coeffs1,
655 const std::vector<double> &coeffs2, const std::vector<double> &coeffs3) {
656
657 //coeffs1=fermi function coeffs, coeffs2[0]=mB, coeffs2[1]=mb,
658 //coeffs2[2]=ymH, coeffs3[0]=DeltaCoeff (alphasmu)
659
660 return FermiFunc(y,coeffs1)*(coeffs2[0]/(coeffs2[1]+y))*
661 Delta((coeffs2[0]*coeffs2[2])/(coeffs2[1]+y),coeffs3[0]);
662
663}
664
665double EvtBtoXsgammaKagan::s77FermiFunc(double y, const std::vector<double> &coeffs1,
666 const std::vector<double> &coeffs2) {
667
668 //coeffs1=fermi function coeffs, coeffs2[0]=mB, coeffs2[1]=mb,
669 //coeffs2[2]=ymH
670 return FermiFunc(y,coeffs1)*(coeffs2[0]/(coeffs2[1]+y))*
671 s77((coeffs2[0]*coeffs2[2])/(coeffs2[1]+y));
672
673}
674
675double EvtBtoXsgammaKagan::s88FermiFunc(double y, const std::vector<double> &coeffs1,
676 const std::vector<double> &coeffs2, const std::vector<double> &coeffs3) {
677
678 //coeffs1=fermi function coeffs, coeffs2[0]=mB, coeffs2[1]=mb,
679 //coeffs2[2]=ymH, coeffs3=s88 coeffs
680 return FermiFunc(y,coeffs1)*(coeffs2[0]/(coeffs2[1]+y))*
681 s88((coeffs2[0]*coeffs2[2])/(coeffs2[1]+y),coeffs3[0], coeffs3[1]);
682
683}
684
685double EvtBtoXsgammaKagan::s78FermiFunc(double y, const std::vector<double> &coeffs1,
686 const std::vector<double> &coeffs2) {
687
688 //coeffs1=fermi function coeffs, coeffs2[0]=mB, coeffs2[1]=mb,
689 //coeffs2[2]=ymH
690 return FermiFunc(y,coeffs1)*(coeffs2[0]/(coeffs2[1]+y))*
691 s78((coeffs2[0]*coeffs2[2])/(coeffs2[1]+y));
692
693}
694
695double EvtBtoXsgammaKagan::sFermiFunc(double y, const std::vector<double> &coeffs1,
696 const std::vector<double> &coeffs2, const std::vector<double> &coeffs3,
697 const std::vector<double> &coeffs4) {
698
699 //coeffs1=fermi function coeffs, coeffs2[0]=mB, coeffs2[1]=mb,
700 //coeffs2[2]=ymH, coeffs3[0]=nIntervals in s22 or s27 array, coeffs3[1]=yMin,
701 //coeffs3[2]=yMax, coeffs4=s22 or s27 array
702 return FermiFunc(y,coeffs1)*(coeffs2[0]/(coeffs2[1]+y))*
703 GetArrayVal(coeffs2[0]*coeffs2[2]/(coeffs2[1]+y), coeffs3[0], coeffs3[1], coeffs3[2], coeffs4);
704
705}
706
707double EvtBtoXsgammaKagan::Fz(double z) {
708
709 return (1. -8.*z + 8.*pow(z,3.) - pow(z,4.) - 12.*pow(z,2.)*log(z));
710}
711
712double EvtBtoXsgammaKagan::GetArrayVal(double xp, double nInterval, double xMin, double xMax, std::vector<double> array) {
713
714 double dx = (xMax - xMin)/nInterval;
715 int bin1 = int(((xp-xMin)/(xMax - xMin))*nInterval);
716
717 double x1 = double(bin1)*dx + xMin;
718
719 if (xp == x1) return array[bin1];
720
721 int bin2(0);
722 if (xp > x1) {
723 bin2 = bin1 + 1;
724 }
725 else if (xp < x1) {
726 bin2 = bin1 - 1;
727 }
728
729 if (bin1 <= 0) {
730 bin1=0;
731 bin2 = 1;
732 }
733
734 //If xp is in the last bin, always interpolate between the last two bins
735 if (bin1 == (int)nInterval){
736 bin2 = (int)nInterval;
737 bin1 = (int)nInterval - 1;
738 x1 = double(bin1)*dx + xMin;
739 }
740
741 double x2 = double(bin2)*dx + xMin;
742 double y1 = array[bin1];
743
744 double y2 = array[bin2];
745 double m = (y2 - y1)/(x2 - x1);
746 double c = y1 - m*x1;
747 double result = m*xp + c;
748
749 return result;
750
751}
752
753double EvtBtoXsgammaKagan::FermiFunc(double y, const std::vector<double> &coeffs) {
754
755 //Fermi shape functions :1=exponential, 2=gaussian, 3=roman
756 if (int(coeffs[0]) == 1) return EvtBtoXsgammaFermiUtil::FermiExpFunc(y, coeffs);
757 if (int(coeffs[0]) == 2) return EvtBtoXsgammaFermiUtil::FermiGaussFunc(y, coeffs);
758 if (int(coeffs[0]) == 3) return EvtBtoXsgammaFermiUtil::FermiRomanFunc(y, coeffs);
759 return 1.;
760
761}
762
763double EvtBtoXsgammaKagan::diLogFunc(double y) {
764
765 return -log(fabs(1. - y))/y;
766
767}
768
769
770double EvtBtoXsgammaKagan::diLogMathematica(double y) {
771
772 double li2(0);
773 for(int i=1; i<1000; i++){ //the value 1000 should actually be Infinite...
774 li2+=pow(y,i)/(i*i);
775 }
776 return li2;
777}