void EvtSSD_DirectCP::init() {
// check that there is 1 argument and 2-body decay
checkNArg(1);
checkNDaug(2);
EvtSpinType::spintype d1type=EvtPDL::getSpinType(getDaug(0));
EvtSpinType::spintype d2type=EvtPDL::getSpinType(getDaug(1));
if ( (!(d1type == EvtSpinType::SCALAR || d2type == EvtSpinType::SCALAR))||
(!((d2type==EvtSpinType::SCALAR)||(d2type==EvtSpinType::VECTOR)||
(d2type==EvtSpinType::TENSOR)))||
(!((d1type==EvtSpinType::SCALAR)||(d1type==EvtSpinType::VECTOR)||
(d1type==EvtSpinType::TENSOR)))
) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "EvtSSD_DirectCP generator expected "
<< "one of the daugters to be a scalar, "
<< "the other either scalar, vector, or tensor, "
<< "found:"
<< EvtPDL::name(getDaug(0)).c_str()
<<" and "
<<EvtPDL::name(getDaug(1)).c_str()<<std::endl;
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Will terminate execution!"<<std::endl;
::abort();
}
_acp = getArg( 0 ) ; // A_CP defined as A_CP = (BR(fbar)-BR(f))/(BR(fbar)+BR(f))
}
void EvtHypNonLepton::init() {
if(getNArg()<2 || getNArg()>3) { // alpha phi gamma delta
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton generator expected 2 or 3 arguments but found: " << getNArg() << std::endl;
EvtGenReport(EVTGEN_INFO ,"EvtGen") << " 1. Decay asymmetry parameter - alpha" << std::endl;
EvtGenReport(EVTGEN_INFO ,"EvtGen") << " 2. Parameter phi - in degrees (not radians)" << std::endl;
EvtGenReport(EVTGEN_INFO ,"EvtGen") << " 3. Note on every x-th decay" << std::endl;
::abort();
}
if(getNDaug()!=2) { // Check that there are 2 daughters only
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton generator expected 2 daughters but found: " << getNDaug() << std::endl;
::abort();
}
// Check particles spins
if(EvtSpinType::getSpin2(EvtPDL::getSpinType(getParentId()))!=1) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton generator expected dirac parent particle, but found " << EvtSpinType::getSpin2(EvtPDL::getSpinType(getParentId())) << " spin degrees of freedom" << std::endl;
::abort();
}
if(EvtSpinType::getSpin2(EvtPDL::getSpinType(getDaug(0)))!=1) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton generator expected the first child to be dirac particle, but found " << EvtSpinType::getSpin2(EvtPDL::getSpinType(getDaug(0))) << " spin degrees of freedom" << std::endl;
::abort();
}
if(EvtSpinType::getSpin2(EvtPDL::getSpinType(getDaug(1)))!=0) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton generator expected the second child to be scalar particle, but found " << EvtSpinType::getSpin2(EvtPDL::getSpinType(getDaug(1))) << " spin degrees of freedom" << std::endl;
::abort();
}
// Read all parameters
m_alpha = getArg(0);
m_phi = getArg(1)*EvtConst::pi/180;
if(getNArg()==3) m_noTries = static_cast<long>(getArg(2));
else m_noTries = 0;
// calculate additional parameters
double p,M,m1,m2;
double p_to_s,beta,delta,gamma;
M = EvtPDL::getMass(getParentId());
m1 = EvtPDL::getMass(getDaug(0));
m2 = EvtPDL::getMass(getDaug(1));
if(m1+m2>=M) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton found impossible decay: " << M << " --> " << m1 << " + " << m2 << " GeV\n" << std::endl;
::abort();
}
p = sqrt(M*M-(m1+m2)*(m1+m2))*sqrt(M*M-(m1-m2)*(m1-m2))/2./M;
beta = sqrt(1.-m_alpha*m_alpha)*sin(m_phi);
delta = -atan2(beta,m_alpha);
gamma = sqrt(1.-m_alpha*m_alpha-beta*beta);
p_to_s = sqrt((1.-gamma)/(1.+gamma));
m_B_to_A = p_to_s*(m1+sqrt(p*p+m1*m1))/p*EvtComplex(cos(delta),sin(delta));
}
int EvtSpinType::getSpinStates(spintype stype){
switch (stype){
case SCALAR: case STRING: case NEUTRINO:
return 1;
case DIRAC: case PHOTON:
return 2;
case VECTOR:
return 3;
case RARITASCHWINGER:
return 4;
case TENSOR:
return 5;
case SPIN5HALF:
return 6;
case SPIN3:
return 7;
case SPIN7HALF:
return 8;
case SPIN4:
return 9;
default:
EvtGenReport(EVTGEN_ERROR,"EvtGen")<<"Unknown spintype in EvtSpinType!"<<std::endl;
return 0;
}
}
void EvtSLBKPoleFF::getraritaff(EvtId, EvtId, double, double, double*, double*,
double*, double*, double*, double*, double*, double*) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Not implemented :getraritaff in EvtSLBKPoleFF.\n";
::abort();
}
void EvtSLBKPoleFF::gettensorff(EvtId parent,EvtId /*daught*/,
double t, double /*mass*/, double *hf,
double *kf, double *bpf, double *bmf ){
if ( numSLBKPoleargs !=16 ) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Problem in EvtSLBKPoleFF::gettensorff\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "wrong number of arguements!!!\n";
}
EvtGenReport(EVTGEN_INFO,"EvtGen")<<"Check the implementation of EvtSLBKPoleFF::gettensorff()!\n";
double mb=EvtPDL::getMeanMass(parent);
double mb2 = mb*mb;
double f0,af,bf,powf;
f0 = SLBKPoleargs[0];
af = SLBKPoleargs[1];
bf = SLBKPoleargs[2];
powf = SLBKPoleargs[3];
*hf = f0/(pow( 1.0 + (af*t/mb2) + (bf*((t/mb2)*(t/mb2))),powf));
f0 = SLBKPoleargs[4];
af = SLBKPoleargs[5];
bf = SLBKPoleargs[6];
powf = SLBKPoleargs[7];
*kf = f0/(pow( 1.0 + (af*t/mb2) + (bf*((t/mb2)*(t/mb2))),powf));
f0 = SLBKPoleargs[8];
af = SLBKPoleargs[9];
bf = SLBKPoleargs[10];
powf = SLBKPoleargs[11];
*bpf = f0/(pow( 1.0 + (af*t/mb2) + (bf*((t/mb2)*(t/mb2))),powf));
f0 = SLBKPoleargs[12];
af = SLBKPoleargs[13];
bf = SLBKPoleargs[14];
powf = SLBKPoleargs[15];
*bmf = f0/(pow( 1.0 + (af*t/mb2) + (bf*((t/mb2)*(t/mb2))),powf));
return;
}
//=============================================================================
// Initialisation method
//=============================================================================
void EvtBToDDalitzCPK::init ( )
{
// Check that there are 3 arguments
checkNArg( 3 ) ;
// Check that there are 2 daughters
checkNDaug( 2 ) ;
// Check that the particles of the decay are :
// B+/- -> D0/bar K+/-
// B+/- -> K+/- D0/bar
// B0/bar -> K*0/bar D0/bar
// and nothing else ...
static EvtId BP = EvtPDL::getId( "B+" ) ;
static EvtId BM = EvtPDL::getId( "B-" ) ;
static EvtId B0 = EvtPDL::getId( "B0" ) ;
static EvtId B0B = EvtPDL::getId( "anti-B0" ) ;
static EvtId KP = EvtPDL::getId( "K+" ) ;
static EvtId KM = EvtPDL::getId( "K-" ) ;
static EvtId KS = EvtPDL::getId( "K*0" ) ;
static EvtId KSB = EvtPDL::getId( "anti-K*0" ) ;
static EvtId D0 = EvtPDL::getId( "D0" ) ;
static EvtId D0B = EvtPDL::getId( "anti-D0" ) ;
_flag = 0 ;
EvtId parent = getParentId() ;
EvtId d1 = getDaug( 0 ) ;
EvtId d2 = getDaug( 1 ) ;
if ( ( ( parent == BP ) || ( parent == BM ) ) &&
( ( d1 == D0 ) || ( d1 == D0B ) ) &&
( ( d2 == KP ) || ( d2 == KM ) ) ) {
_flag = 1 ;
// PHSP Decay
}
else if ( ( ( parent == BP ) || ( parent == BM ) ) &&
( ( d1 == KP ) || ( d1 == KM ) ) &&
( ( d2 == D0 ) || ( d2 == D0B ) ) ) {
_flag = 1 ;
// also PHSP decay
}
else if ( ( ( parent == B0 ) || ( parent == B0B ) ) &&
( ( d1 == KS ) || ( d1 == KSB ) ) &&
( ( d2 == D0 ) || ( d2 == D0B ) ) ) {
_flag = 2 ;
// SVS Decay
}
if ( _flag == 0 ) {
EvtGenReport(EVTGEN_ERROR , "EvtGen" ) << "EvtBToDDalitzCPK : Invalid mode."
<< std::endl ;
assert( 0 ) ;
}
}
void EvtHypNonLepton::initProbMax() {
double maxProb,m1,m2,M,p;
M=EvtPDL::getMass(getParentId());
m1=EvtPDL::getMass(getDaug(0));
m2=EvtPDL::getMass(getDaug(1));
if(m1+m2>=M) {
EvtGenReport(EVTGEN_ERROR,"EvtGen") << " ERROR: EvtHypNonLepton found impossible decay: " << M << " --> " << m1 << " + " << m2 << " GeV\n" << std::endl;
::abort();
}
p=sqrt(M*M-(m1+m2)*(m1+m2))*sqrt(M*M-(m1-m2)*(m1-m2))/2/M;
maxProb=16*M*(sqrt(p*p+m1*m1)+m1+abs(m_B_to_A)*abs(m_B_to_A)*(sqrt(p*p+m1*m1)-m1));
//maxProb *= G_F*M_pi*M_pi;
setProbMax(maxProb);
EvtGenReport(EVTGEN_INFO,"EvtGen") << " EvtHypNonLepton set up maximum probability to " << maxProb << std::endl;
}
void EvtSLBKPoleFF::getscalarff(EvtId parent,EvtId daught,
double t, double /*mass*/, double *fpf,
double *f0f ) {
// Form factors have a general form, with parameters passed in
// from the arguments.
if ( numSLBKPoleargs != 4 ) {//modified
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Problem in EvtSLBKPoleFF::getscalarff\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "wrong number of arguments!\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "number args:"<<numSLBKPoleargs<<" (expected 4)\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Parent:"<<EvtPDL::name(parent)<<"\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Daughter:"<<EvtPDL::name(daught)<<"\n";
}
double f0,af,powf;
//double a_0, a_1, a_2, a_3, a_4, a_5, a_6, a_7;
f0 = SLBKPoleargs[0];//f0
af = SLBKPoleargs[1];//alpha
//bf = SLBKPoleargs[2];
double mass_star2 = SLBKPoleargs[3]*SLBKPoleargs[3];
powf = 1.0;
*fpf = f0/(pow( 1.0 - (1.0+af)*(t/mass_star2) + (af*((t/mass_star2)*(t/mass_star2))),powf));//modified
f0 = SLBKPoleargs[0];//f0
af = SLBKPoleargs[2];//beta
//bf = SLBKPoleargs[6];
powf = 1.0;
*f0f = f0/(pow( 1.0 - (t/mass_star2/af),powf));//modified
return;
}
// Set the maximum probability of the decay
void EvtB2MuMuMuNu::initProbMax(){
double mymaxprob=-10.0; // maximum of the probability
mymaxprob = _calcamp->CalcMaxProb();
if(mymaxprob <= 0.0){
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "The function void EvtB2MuMuMuNu::initProbMax()"
<< "\n Unexpected value of the probability maximum!"
<< "\n mymaxprob = " << mymaxprob
<<std::endl;
::abort();
}
setProbMax(mymaxprob);
}
// Set the maximum probability of the decay
void EvtbsToLLLL::initProbMax(){
double mymaxprob=-10.0; // maximum of the probability
// EvtId parnum, l1num, l2num, l3num, l4num;
// parnum = getParentId();
// l1num = getDaug(0);
// l2num = getDaug(1);
// l3num = getDaug(2);
// l4num = getDaug(3);
// EvtSpinType::spintype mesontype=EvtPDL::getSpinType(getDaug(0));
// double mu = getArg(0); // the scale parameter
// int Nf = (int) getArg(1); // number of "effective" flavors
// int res_swch = (int) getArg(2); // resonant switching parametr
// int ias = (int) getArg(3); // switching parametr for \alpha_s(M_Z)
// double CKM_A = getArg(4);
// double CKM_lambda = getArg(5);
// double CKM_barrho = getArg(6);
// double CKM_bareta = getArg(7);
mymaxprob = _calcamp->CalcMaxProb(
// parnum, l1num,l2num, l3num,l4num,
// _mntffmodel, _wilscoeff,
// mu, Nf, res_swch, ias,
// CKM_A,CKM_lambda,CKM_barrho,CKM_bareta
);
if(mymaxprob <= 0.0){
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "The function void EvtbsToLLLL::initProbMax()"
<< "\n Unexpected value of the probability maximum!"
<< "\n mymaxprob = " << mymaxprob
<<std::endl;
::abort();
}
setProbMax(mymaxprob);
}
void EvtHypNonLepton::calcAmp(EvtAmp *amp,EvtParticle *parent) {
static long noTries=0;
int i;
EvtComplex Matrix[2][2];
//G_F = 1.16637e-5;
//M_pi = 0.13957;
for(i=0; i<4; i++) {
//std::cout << "--------------------------------------------------" << std::endl;
Matrix[i/2][i%2] = EvtLeptonSCurrent(parent->sp(i/2),parent->getDaug(0)->spParent(i%2));
//std::cout << "Matrix = " << Matrix[i/2][i%2] << std::endl;
Matrix[i/2][i%2] -= m_B_to_A*EvtLeptonPCurrent(parent->sp(i/2),parent->getDaug(0)->spParent(i%2));
//std::cout << "Matrix = " << Matrix[i/2][i%2] << std::endl;
//Matrix[i/2][i%2] *= G_F*M_pi*M_pi;
//std::cout << "Matrix = " << Matrix[i/2][i%2] << std::endl;
//std::cout << "--------------------------------------------------" << std::endl;
amp->vertex(i/2,i%2,Matrix[i/2][i%2]);
}
if(m_noTries>0) if(!((++noTries)%m_noTries)) EvtGenReport(EVTGEN_DEBUG,"EvtGen") << " EvtHypNonLepton already finished " << noTries << " matrix element calculations" << std::endl;
}
void EvtPVVCPLH::decay( EvtParticle *p){
//added by Lange Jan4,2000
static EvtId BS0=EvtPDL::getId("B_s0");
static EvtId BSB=EvtPDL::getId("anti-B_s0");
//This is only to get tag-ID
//Mixing is not relevant
//Lifetime is made correctly later
//Tristan
EvtId other_b;
double t;
// To generate integrated CP asymmetry, EvtGen uses the "flipping".
// CP-asymmetry in this channel very small, since:
// deltaMs large ..and..
// CPV-phase small
EvtCPUtil::getInstance()->OtherB(p,t,other_b);
//Here we're gonna generate and set the "envelope" lifetime
//So we take the longest living component (for positive deltaGamma: tauH)
//The double exponent will be taken care of later, by the amplitudes
//Tristan
static double Gamma = EvtConst::c/(EvtPDL::getctau(BS0));
static double deltaGamma = EvtCPUtil::getInstance()->getDeltaGamma(BS0);
static double ctauLong = EvtConst::c/(Gamma-fabs(deltaGamma)/2);
// if dG>0: tauLong=tauH(CP-odd) is then largest
//This overrules the lifetimes made in OtherB
t=-log(EvtRandom::Flat())*(ctauLong);//ctauLong has same dimensions as t
if(isBsMixed(p)){
p->getParent()->setLifetime(t);
}else{
p->setLifetime(t);
}
//These should be filled with the transversity amplitudes at t=0 //Tristan
EvtComplex G0P,G1P,G1M;
G1P=EvtComplex(getArg(2)*cos(getArg(3)),getArg(2)*sin(getArg(3)));
G0P=EvtComplex(getArg(4)*cos(getArg(5)),getArg(4)*sin(getArg(5)));
G1M=EvtComplex(getArg(6)*cos(getArg(7)),getArg(6)*sin(getArg(7)));
EvtComplex lambda_km=EvtComplex(cos(2*getArg(0)),sin(2*getArg(0)));//was een min in oude versie
//deltaMs is no argument anymore
//Tristan
static double deltaMs = EvtCPUtil::getInstance()->getDeltaM(BS0);
EvtComplex cG0P,cG1P,cG1M;
double mt = exp(-std::max(0.,deltaGamma)*t/(2*EvtConst::c));
double pt = exp(+std::min(0.,deltaGamma)*t/(2*EvtConst::c));
EvtComplex gplus = ( mt*EvtComplex(cos(deltaMs*t/(2*EvtConst::c)),sin( deltaMs*t/(2*EvtConst::c)))
+pt*EvtComplex(cos(deltaMs*t/(2*EvtConst::c)),sin(-deltaMs*t/(2*EvtConst::c))) )/2;
EvtComplex gminus = ( mt*EvtComplex(cos(deltaMs*t/(2*EvtConst::c)),sin( deltaMs*t/(2*EvtConst::c)))
-pt*EvtComplex(cos(deltaMs*t/(2*EvtConst::c)),sin(-deltaMs*t/(2*EvtConst::c))) )/2;;
if (other_b==BSB){
//These are the right equations for the transversity formalism
//cGOP is de 0-component, CP-even, so lives shorter: mainly lifetime tauL
//cG1P is the //-component, also CP-even, also mainly smaller exponent
//cG1M is the transverse component, CP-odd, so has mainly longer lifetime tauH
//Tristan
cG0P = G0P*( gplus + lambda_km*gminus );
cG1P = G1P*( gplus + lambda_km*gminus );
cG1M = G1M*( gplus - lambda_km*gminus );
} else if (other_b==BS0){
//The equations for BsBar
//Note the minus-sign difference
//Tristan
cG0P = G0P*( gplus + (1.0/lambda_km)*gminus );
cG1P = G1P*( gplus + (1.0/lambda_km)*gminus );
cG1M =-G1M*( gplus - (1.0/lambda_km)*gminus );
} else{
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "other_b was not BSB or BS0!"<<std::endl;
::abort();
}
EvtComplex A0,AP,AM;
//Converting the transversity amplitudes
//to helicity amplitudes
//(to plug them into SVVHelAmp)
A0=cG0P;
AP=(cG1P+cG1M)/sqrt(2.0);
AM=(cG1P-cG1M)/sqrt(2.0);
EvtSVVHelAmp::SVVHel(p,_amp2,getDaug(0),getDaug(1),AP,A0,AM);
return ;
}
void EvtSLBKPoleFF::getvectorff(EvtId parent,EvtId /*daught*/,
double t, double /*mass*/, double *a1f,
double *a2f, double *vf, double *a0f ){
if ( numSLBKPoleargs !=8 ) {//modified
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "Problem in EvtSLBKPoleFF::getvectorff\n";//modified
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "wrong number of arguements!!!\n";
EvtGenReport(EVTGEN_ERROR,"EvtGen") << numSLBKPoleargs<<"\n";//modified
// printf("\n*********************%d*********************",numSLBKPoleargs);
}
EvtGenReport(EVTGEN_INFO,"EvtGen")<<"Check the implementation of EvtSLBKPoleFF::getvectorff()!\n";
double mb=EvtPDL::getMeanMass(parent);
double mb2 = mb*mb;
//modified-begin
static EvtId B0=EvtPDL::getId("B0");
static EvtId B0B=EvtPDL::getId("anti-B0");
static EvtId BP=EvtPDL::getId("B+");
static EvtId BM=EvtPDL::getId("B-");
static EvtId BS0=EvtPDL::getId("B_s0");
static EvtId B0S=EvtPDL::getId("B*0");
static EvtId BPMS=EvtPDL::getId("B*+");
static EvtId BS0S=EvtPDL::getId("B_s*0");
static EvtId D0=EvtPDL::getId("D0");
static EvtId D0B=EvtPDL::getId("anti-D0");
static EvtId DP=EvtPDL::getId("D+");
static EvtId DM=EvtPDL::getId("D-");
static EvtId DSP=EvtPDL::getId("D_s+");
static EvtId DSM=EvtPDL::getId("D_s-");
static EvtId D0S=EvtPDL::getId("D*0");
static EvtId DPMS=EvtPDL::getId("D*+");
static EvtId DSPMS=EvtPDL::getId("D_s*+");
double mass_star=0.0;
double mass_star2=0.0;
if(parent==B0||parent==B0B){
mass_star=EvtPDL::getMeanMass(B0S);
mass_star2=mass_star*mass_star;
}
if(parent==BP||parent==BM){
mass_star=EvtPDL::getMeanMass(BPMS);
mass_star2=mass_star*mass_star;
}
if(parent==BS0){
mass_star=EvtPDL::getMeanMass(BS0S);
mass_star2=mass_star*mass_star;
}
if(parent==D0||parent==D0B){
mass_star=EvtPDL::getMeanMass(D0S);
mass_star2=mass_star*mass_star;
}
if(parent==DP||parent==DM){
mass_star=EvtPDL::getMeanMass(DPMS);
mass_star2=mass_star*mass_star;
}
if(parent==DSP||parent==DSM){
mass_star=EvtPDL::getMeanMass(DSPMS);
mass_star2=mass_star*mass_star;
}
//modified-end
double f0,af,bf,powf;
f0 = SLBKPoleargs[2];//A1
af = SLBKPoleargs[6];//b'
bf = 0;//0
powf = 1.0;//1.0
*a1f = f0/(pow( 1.0 - af*t/mass_star2,powf));//modified
f0 = SLBKPoleargs[3];//A2
af = SLBKPoleargs[6];//b'
bf = SLBKPoleargs[7];//b''==0
powf = 1.0;//1.0
*a2f = f0/(pow(1.0 - (af+bf)*(t/mass_star2) + (af*bf)*((t/mass_star2)*(t/mass_star2)),powf));//modified
f0 = SLBKPoleargs[0];//V0
af = SLBKPoleargs[4];//a
bf = 0;//0
powf = 1.0;//1.0
*vf = f0/(pow( 1.0 - (1.0+af)*(t/mass_star2) + af*(t/mass_star2)*(t/mass_star2),powf));//modified
f0 = SLBKPoleargs[1];//A0
af = SLBKPoleargs[5];//a'
bf = 0;//0
powf = 1.0;//1.0
*a0f = f0/(pow( 1.0 - (1.0+af)*(t/mb2) + af*((t/mb2)*(t/mb2)),powf));//modified
return;
}
void EvtSemiLeptonicScalarAmp::CalcAmp( EvtParticle *parent,
EvtAmp& amp,
EvtSemiLeptonicFF *FormFactors ) {
static EvtId EM=EvtPDL::getId("e-");
static EvtId MUM=EvtPDL::getId("mu-");
static EvtId TAUM=EvtPDL::getId("tau-");
static EvtId EP=EvtPDL::getId("e+");
static EvtId MUP=EvtPDL::getId("mu+");
static EvtId TAUP=EvtPDL::getId("tau+");
//Add the lepton and neutrino 4 momenta to find q2
EvtVector4R q = parent->getDaug(1)->getP4()
+ parent->getDaug(2)->getP4();
double q2 = (q.mass2());
double fpf,f0f;
double mesonmass = parent->getDaug(0)->mass();
double parentmass = parent->mass();
FormFactors->getscalarff(parent->getId(),
parent->getDaug(0)->getId(),
q2,
mesonmass,
&fpf,
&f0f);
EvtVector4R p4b;
p4b.set(parent->mass(),0.0,0.0,0.0);
EvtVector4R p4meson = parent->getDaug(0)->getP4();
double mdiffoverq2;
mdiffoverq2 = parentmass*parentmass - mesonmass*mesonmass;
mdiffoverq2 = mdiffoverq2 / q2;
EvtVector4C l1,l2;
EvtId l_num = parent->getDaug(1)->getId();
EvtVector4C tds;
if (l_num==EM||l_num==MUM||l_num==TAUM){
tds = EvtVector4C(fpf*(p4b+p4meson - (mdiffoverq2*(p4b-p4meson)))+
+ f0f*mdiffoverq2*(p4b-p4meson));
l1=EvtLeptonVACurrent(parent->getDaug(1)->spParent(0),
parent->getDaug(2)->spParentNeutrino());
l2=EvtLeptonVACurrent(parent->getDaug(1)->spParent(1),
parent->getDaug(2)->spParentNeutrino());
}
else{
if (l_num==EP||l_num==MUP||l_num==TAUP){
tds = EvtVector4C(fpf*(p4b+p4meson - (mdiffoverq2*(p4b-p4meson)))+
+ f0f*mdiffoverq2*(p4b-p4meson));
l1=EvtLeptonVACurrent(parent->getDaug(2)->spParentNeutrino(),
parent->getDaug(1)->spParent(0));
l2=EvtLeptonVACurrent(parent->getDaug(2)->spParentNeutrino(),
parent->getDaug(1)->spParent(1));
}
else{
EvtGenReport(EVTGEN_ERROR,"EvtGen") << "dfnb89agngri wrong lepton number\n";
}
}
amp.vertex(0,l1*tds);
amp.vertex(1,l2*tds);
}
void EvtB2MuMuMuNuAmp::CalcAmp(EvtParticle *parent,
EvtAmp& amp,
EvtbTosllMSFF *formFactorsms){
// Check the charge conservation in the reaction
int charge[4];
charge[0] = (EvtPDL::chg3(parent->getDaug(0)->getId()))/3;
charge[1] = (EvtPDL::chg3(parent->getDaug(1)->getId()))/3;
charge[2] = (EvtPDL::chg3(parent->getDaug(2)->getId()))/3;
charge[3] = (EvtPDL::chg3(parent->getDaug(3)->getId()))/3;
if(abs(charge[0]+charge[1]+charge[2]+charge[3])!=1){
EvtGenReport(EVTGEN_ERROR,"EvtGen")
<< "\n\n The function EvtB2MuMuMuNuAmp::CalcAmp(...)"
<< "\n Error in the daughters charge definition!"
<< "\n charge1 = " << charge[0]
<< "\t KF code1 = " << EvtPDL::getLundKC(parent->getDaug(0)->getId())
<< "\n charge2 = " << charge[1]
<< "\t KF code2 = " << EvtPDL::getLundKC(parent->getDaug(1)->getId())
<< "\n charge3 = " << charge[2]
<< "\t KF code3 = " << EvtPDL::getLundKC(parent->getDaug(2)->getId())
<< "\n charge4 = " << charge[3]
<< "\t KF code4 = " << EvtPDL::getLundKC(parent->getDaug(3)->getId())
<< "\n number of daughters = " << parent->getNDaug()
<< std::endl;
::abort();
}
// Daughter's positions in the matrix element
int il1, il2, il3, il4; // Mu^+(k_1), Mu^-(k_2), \bar Nu_{Mu}(k_3) and Mu^-(k_4)
//or Mu^-(k_1), Mu^+(k_2), Nu_{Mu}(k_3) and Mu^+(k_4)
// This is the "canonical set" for current matrix element.
il1 = -101; //initialization of the daughter's positions
il2 = -102;
il3 = -103;
il4 = -104;
// Daughter's positions for the decay
// B^-(p) -> Mu^+(k_1) Mu^-(k_2) \bar Nu_{Mu}(k_3) Mu^-(k_4).
if(charge[0]+charge[1]+charge[2]+charge[3] == -1){
int ll;
int min_charge, min_charge_il;
min_charge = charge[0];
min_charge_il = 0;
for(ll = 1; ll < 4; ll++){
if(min_charge > charge[ll]){
min_charge = charge[ll];
min_charge_il = ll;
}
}
il2 = min_charge_il; // this is Mu^-(k_2)
if(il2 > 2){
EvtGenReport(EVTGEN_ERROR,"EvtGen")
<< "\n\n The function EvtB2MuMuMuNuAmp::CalcAmp(...)"
<< "\n Error in the particles distribution!"
<< "\n il2 = " << il2
<< "\n min_charge = " << min_charge
<< "\n total charge = -1 = " << (charge[0]+charge[1]+charge[2]+charge[3])
<< std::endl;
::abort();
}
for(ll = il2 + 1; ll < 4; ll++){
if(charge[ll] == -1) il4 = ll; // this is Mu^-(k_4)
}
for(ll = 0; ll < 4; ll++){
if(charge[ll] == +1) il1 = ll; // this is Mu^+(k_1)
}
for(ll = 0; ll < 4; ll++){
if(charge[ll] == 0) il3 = ll; // this is \bar Nu_{Mu}(k_3)
}
}
// Daughter's positions for the decay
// B^+(p) -> Mu^-(k_1) Mu^+(k_2) Nu_{Mu}(k_3) Mu^+(k_4).
if(charge[0]+charge[1]+charge[2]+charge[3] == 1){
int ll;
int max_charge, max_charge_il;
max_charge = charge[0];
max_charge_il = 0;
for(ll = 1; ll < 4; ll++){
if(max_charge < charge[ll]){
max_charge = charge[ll];
max_charge_il = ll;
}
}
il2 = max_charge_il; // this is Mu^+(k_2)
if(il2 > 2){
EvtGenReport(EVTGEN_ERROR,"EvtGen")
<< "\n\n The function EvtB2MuMuMuNuAmp::CalcAmp(...)"
<< "\n Error in the particles distribution!"
<< "\n il2 = " << il2
<< "\n max_charge = " << max_charge
<< "\n total charge = +1 = " << (charge[0]+charge[1]+charge[2]+charge[3])
<< std::endl;
::abort();
}
for(ll = il2 + 1; ll < 4; ll++){
if(charge[ll] == 1) il4 = ll; // this is Mu^+(k_4)
}
for(ll = 0; ll < 4; ll++){
if(charge[ll] == -1) il1 = ll; // this is Mu^-(k_1)
}
for(ll = 0; ll < 4; ll++){
if(charge[ll] == 0) il3 = ll; // this is Nu_{Mu}(k_3)
}
}
if((il1 < 0)||(il2 < 0)|| (il3 < 0) || (il4 < 0)){
EvtGenReport(EVTGEN_ERROR,"EvtGen")
<< "\n\n The function EvtB2MuMuMuNuAmp::CalcAmp(...)"
<< "\n ilX < 0 !!!"
<< "\n il1 = " << il1
<< "\t il2 = " << il2
<< "\t il3 = " << il3
<< "\t il4 = " << il4
<< std::endl;
::abort();
}
// Output for program work check.
// Need to comment in the final version!
// EvtGenReport(EVTGEN_ERROR,"EvtGen")
// << "\n il1 = " << il1
// << "\t il2 = " << il2
// << "\t il3 = " << il3
// << "\t il4 = " << il4
// << std::endl;
//END of the daughter's positions initialization
// Kinematics initialization
EvtComplex unit1(1.0,0.0); // real unit
EvtComplex uniti(0.0,1.0); // imaginary unit
double M1 = parent->mass(); // B-meson mass, GeV
double ml = parent->getDaug(il1)->mass(); // mass of muon, GeV
// Id and 4-momentums of the particles
EvtId idparent = parent->getId(); // B-meson Id
EvtVector4R p; // B-meson 4-momentum
p.set(0.0,0.0,0.0,0.0);
EvtId id_L1, id_L2, id_L3, id_L4; // leptonic Id
EvtVector4R k_1; // 4-momentum of mu^+ in the B^- rest frame; (il1)
EvtVector4R k_2; // 4-momentum of mu^- in the B^- rest frame; (il2)
EvtVector4R k_3; // 4-momentum of \bar nu in the B^- rest frame; (il3)
EvtVector4R k_4; // 4-momentum of mu^- in the B^- rest frame; (il4)
k_1.set(0.0,0.0,0.0,0.0);
k_2.set(0.0,0.0,0.0,0.0);
k_3.set(0.0,0.0,0.0,0.0);
k_4.set(0.0,0.0,0.0,0.0);
EvtVector4R q_fierst; // q = k_1 + k_2 4-momentum in the B-rest frame
EvtVector4R k_fierst; // k = k_3 + k_4 4-momentum in the B-rest frame
double q2_fierst; // Mandelstam variable s=q^2
double k2_fierst; // Mandelstam variable t=k^2
EvtVector4R q_second; // q = k_1 + k_4 4-momentum in the B-rest frame
EvtVector4R k_second; // k = k_3 + k_2 4-momentum in the B-rest frame
double q2_second; // Mandelstam variable s=q^2
double k2_second; // Mandelstam variable t=k^2
p = parent->getP4Restframe(); // B-meson 4-momentum in the B-rest frame
k_1 = parent->getDaug(il1)->getP4();
k_2 = parent->getDaug(il2)->getP4();
k_3 = parent->getDaug(il3)->getP4();
k_4 = parent->getDaug(il4)->getP4();
q_fierst = k_1 + k_2;
k_fierst = k_3 + k_4;
q2_fierst = q_fierst.mass2();
k2_fierst = k_fierst.mass2();
q_second = k_1 + k_4;
k_second = k_3 + k_2;
q2_second = q_second.mass2();
k2_second = k_second.mass2();
// For "B^-" - and "B^+" - mesons amplitudeы separately calculations
static EvtIdSet bmesons("B-","B_c-");
static EvtIdSet bbarmesons("B+","B_c+");
// // Information for test of 4-momentum.
// // Need to comment in the final version!
// EvtGenReport(EVTGEN_ERROR,"EvtGen")
// << "\n 4-momentum initialization test"
// << "\n k_1 = " << k_1
// << "\n k_2 = " << k_2
// << "\n k_3 = " << k_3
// << "\n k_4 = " << k_4
// << "\n q_fierst = " << q_fierst
// << "\n q_second = " << q_second
// << "\n k_fierst = " << k_fierst
// << "\n k_second = " << k_second
// << std::endl;
//
// I. VMD Contribution
//
double M2[4]; //intermediate vector mesons mass for VMD contribution
// M2[0] = EvtPDL::getMass(EvtPDL::getId(std::string("rho0"))); // Rho^0
// M2[1] = EvtPDL::getMass(EvtPDL::getId(std::string("omega"))); // Omega^0
// M2[2] = M2[0]; // GeV Rho^0
// M2[3] = M2[1]; // GeV Omega^0
M2[0] = 0.77526; // GeV Rho^0
M2[1] = 0.78265; // GeV Omega^0
M2[2] = M2[0]; // GeV Rho^0
M2[3] = M2[1]; // GeV Omega^0
double Width2[4]; //intermediate vector mesons width for VMD contribution
// Width2[0] = EvtPDL::getWidth(EvtPDL::getId(std::string("rho0"))); // Rho^0
// Width2[1] = EvtPDL::getWidth(EvtPDL::getId(std::string("omega"))); // Omega^0
// Width2[2] = Width2[0]; // GeV Rho^0
// Width2[3] = Width2[1]; // GeV Omega^0
Width2[0] = 0.1491; // GeV Rho^0
Width2[1] = 0.00849; // GeV Omega^0
Width2[2] = Width2[0]; // GeV Rho^0
Width2[3] = Width2[1]; // GeV Omega^0
double fV2[4]; //intermediate vector mesons leptonic constant for VMD contribution
// see D.Melikhov, N.Nikitin. PRD70, 114028 (2004)
fV2[0] = 5.04; // GeV Rho^0
fV2[1] = 17.1; // GeV Omega^0
fV2[2] = 5.04; // GeV Rho^0
fV2[3] = 17.1; // GeV Omega^0
// For taking the form factors values
// B -> V intermediate vector mesons
// transition form-factors for VMD contribution
// 0 -- Rho^0 for k2_fierst
// 1 -- Omega^0 for k2_fierst
// 2 -- Rho^0 for k2_second
// 3 -- Omega^0 for k2_second
double a1[4],a2[4],a3[4],a0[4],v[4],t1[4],t2[4],t3[4];
EvtId B_meson_for_FF = EvtPDL::getId(std::string("B0"));
EvtId rho_meson_for_FF = EvtPDL::getId(std::string("rho0"));
EvtId omega_meson_for_FF = EvtPDL::getId(std::string("omega"));
formFactorsms->getVectorFF(B_meson_for_FF, rho_meson_for_FF, k2_fierst,
a1[0],a2[0],a0[0],v[0],t1[0],t2[0],t3[0]);
formFactorsms->getVectorFF(B_meson_for_FF, omega_meson_for_FF, k2_fierst,
a1[1],a2[1],a0[1],v[1],t1[1],t2[1],t3[1]);
formFactorsms->getVectorFF(B_meson_for_FF, rho_meson_for_FF, k2_second,
a1[2],a2[2],a0[2],v[2],t1[2],t2[2],t3[2]);
formFactorsms->getVectorFF(B_meson_for_FF, omega_meson_for_FF, k2_second,
a1[3],a2[3],a0[3],v[3],t1[3],t2[3],t3[3]);
int aa;
for(aa = 0; aa < 4; aa++){
a3[aa] = ((M1 + M2[aa])*a1[aa] - (M1 - M2[aa])*a2[aa])/(2.0*M2[aa]);
}
// // Information for test of VMD contribution.
// // Need to comment in the final version!
// EvtGenReport(EVTGEN_ERROR,"EvtGen")
// << "\n VMD Contribution test"
// << "\n M(Bu) = " << M1 << " GeV;"
// << "\n M(Rho) = " << M2[0] << " GeV;"
// << "\t M(Omega) = " << M2[1] << " GeV;"
// << "\t Gamma(Rho) = " << Width2[0] << " Gev;"
// << "\t Gamma(Omega) = " << Width2[1] << " Gev."
// << "\n\n a1[0] = " << a1[0]
// << "\t a2[0] = " << a2[0]
// << "\t a0[0] = " << a0[0]
// << "\t a3[0] = " << a3[0]
// << "\t v[0] = " << v[0]
// << "\n\n a1[1] = " << a1[1]
// << "\t a2[1] = " << a2[1]
// << "\t a0[1] = " << a0[1]
// << "\t a3[1] = " << a3[1]
// << "\t v[1] = " << v[1]
// << "\n\n a1[2] = " << a1[2]
// << "\t a2[2] = " << a2[2]
// << "\t a0[2] = " << a0[2]
// << "\t a3[2] = " << a3[2]
// << "\t v[2] = " << v[2]
// << "\n\n a1[3] = " << a1[3]
// << "\t a2[3] = " << a2[3]
// << "\t a0[3] = " << a0[3]
// << "\t a3[3] = " << a3[3]
// << "\t v[3] = " << v[3]
// << std::endl;
// Tensor structures for VMD contribution
EvtTensor4C Tvmd_fierst, Tvmd_second;
//
// II. Electromagnetic foton emission from B-meson contribution
// (EM contribution)
//
// EM form factors
// 0 -- u-quark emission for q2_fierst
// 1 -- b-quark emission for q2_fierst
// 2 -- u-quark emission for q2_second
// 3 -- b-quark emission for q2_second
double v_em[4];
double MBstar = 5.325; // GeV
v_em[0] = 4.0*MBstar*FF_B2BstarGamma_fromU(q2_fierst)/(3.0*(M1 + MBstar));
v_em[1] = 2.0*MBstar*FF_B2BstarGamma_fromB(q2_fierst)/(3.0*(M1 + MBstar));
v_em[2] = 4.0*MBstar*FF_B2BstarGamma_fromU(q2_second)/(3.0*(M1 + MBstar));
v_em[3] = 2.0*MBstar*FF_B2BstarGamma_fromB(q2_second)/(3.0*(M1 + MBstar));
// Tensor structures for EM contribution
EvtTensor4C Tem_fierst, Tem_second;
//
// ***
//
// Leptonic currents
// L1 = (\bar mu \gamma^{\mu} (1 - \gamma^5) nu)
// or (\bar nu \gamma^{\mu} (1 - \gamma^5) mu)
// L2 = (\bar mu \gamma^{\nu} mu)
EvtVector4C L1_fierst, L2_fierst;
EvtVector4C L1_second, L2_second;
int i1, i2, i3, i4; // leptonic spin structures counters
int leptonicspin[4]; // array for the saving of the leptonic spin configuration
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Contribution for B- decay +
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
if (bmesons.contains(idparent)){
Tvmd_fierst = 0.0*EvtTensor4C::g();
for(aa = 0; aa < 2; aa++){
EvtComplex coeff_vmd;
double Re_vmd, Im_vmd, znam_vmd;
Re_vmd = q2_fierst - M2[aa]*M2[aa];
Im_vmd = Width2[aa]*M2[aa];
znam_vmd = fV2[aa]*(Re_vmd*Re_vmd + Im_vmd*Im_vmd);
coeff_vmd = unit1*Re_vmd/znam_vmd - uniti*Im_vmd/znam_vmd;
double vaa, a2aa, a3aa;
vaa = 2.0*v[aa]/(M1 + M2[aa]);
a2aa = a2[aa]/(M1 + M2[aa]);
a3aa = 2.0*M2[aa]*(a3[aa] - a0[aa])/k2_fierst;
Tvmd_fierst = Tvmd_fierst
+coeff_vmd*(0.0*EvtTensor4C::g()
-(unit1*vaa*dual(EvtGenFunctions::directProd(p,q_fierst)))
-uniti*a1[aa]*(M1 + M2[aa])*EvtTensor4C::g()
+uniti*a2aa*EvtGenFunctions::directProd((p + q_fierst),p)
+uniti*a3aa*EvtGenFunctions::directProd((p - q_fierst),p));
}
Tvmd_second = 0.0*EvtTensor4C::g();
for(aa = 2; aa < 4; aa++){
EvtComplex coeff_vmd;
double Re_vmd, Im_vmd, znam_vmd;
Re_vmd = q2_second - M2[aa]*M2[aa];
Im_vmd = Width2[aa]*M2[aa];
znam_vmd = fV2[aa]*(Re_vmd*Re_vmd + Im_vmd*Im_vmd);
coeff_vmd = unit1*Re_vmd/znam_vmd - uniti*Im_vmd/znam_vmd;
double vaa, a2aa, a3aa;
vaa = 2.0*v[aa]/(M1 + M2[aa]);
a2aa = a2[aa]/(M1 + M2[aa]);
a3aa = 2.0*M2[aa]*(a3[aa] - a0[aa])/k2_second;
Tvmd_second = Tvmd_second
+coeff_vmd*(0.0*EvtTensor4C::g()
-unit1*vaa*dual(EvtGenFunctions::directProd(p,q_second))
-uniti*a1[aa]*(M1 + M2[aa])*EvtTensor4C::g()
+uniti*a2aa*EvtGenFunctions::directProd((p + q_second),p)
+uniti*a3aa*EvtGenFunctions::directProd((p - q_second),p));
}
Tem_fierst = 0.0*EvtTensor4C::g();
for(aa = 0; aa < 2; aa++){
double fBstar = 0.2; // GeV
double coeff;
coeff = fBstar/(q2_fierst*(k2_fierst - MBstar*MBstar));
Tem_fierst = Tem_fierst - coeff*v_em[aa]*dual(EvtGenFunctions::directProd(p,k_fierst));
}
Tem_second = 0.0*EvtTensor4C::g();
for(aa = 2; aa < 4; aa++){
double fBstar = 0.2; // GeV
double coeff;
coeff = fBstar/(q2_fierst*(k2_fierst - MBstar*MBstar));
Tem_second = Tem_second - coeff*v_em[aa]*dual(EvtGenFunctions::directProd(p,k_second));
}
// Amplitude calculation
for(i2=0;i2<2;i2++){
leptonicspin[0] = i2;
for(i1=0;i1<2;i1++){
leptonicspin[1] = i1;
for(i4=0;i4<2;i4++){
leptonicspin[2] = i4;
i3 = 0; // neutrino spin structure!
leptonicspin[3] = i3;
//(\bar mu(k_4) \gamma^{\mu} (1 - \gamma^5) nu(- k_3))
L1_fierst = EvtLeptonVACurrent(parent->getDaug(il4)->spParent(i4),
parent->getDaug(il3)->spParentNeutrino());
//(\bar mu(k_2) \gamma^{\mu} mu(- k_1))
L2_fierst = EvtLeptonVCurrent(parent->getDaug(il2)->spParent(i2),
parent->getDaug(il1)->spParent(i1));
//(\bar mu(k_2) \gamma^{\mu} (1 - \gamma^5) nu(- k_3))
L1_second = EvtLeptonVACurrent(parent->getDaug(il2)->spParent(i2),
parent->getDaug(il3)->spParentNeutrino());
//(\bar mu(k_4) \gamma^{\mu} mu(- k_1))
L2_second = EvtLeptonVCurrent(parent->getDaug(il4)->spParent(i4),
parent->getDaug(il1)->spParent(i1));
// VMD
EvtVector4C Evmd_fierst, Evmd_second;
Evmd_fierst=Tvmd_fierst.cont2(L2_fierst);
Evmd_second=Tvmd_second.cont2(L2_second);
// EM
EvtVector4C Eem_fierst, Eem_second;
Eem_fierst=Tem_fierst.cont2(L1_fierst);
Eem_second=Tem_second.cont2(L1_second);
// Bremsstrahlung
EvtComplex Ebrst_fierst, Ebrst_second;
double fB = 0.20; // GeV leptonic constant of B^{\pm} mesons
Ebrst_fierst = uniti*fB*L2_fierst*L1_fierst/q2_fierst;
Ebrst_second = uniti*fB*L2_second*L1_second/q2_second;
amp.vertex(leptonicspin, L1_fierst*Evmd_fierst + L2_fierst*Eem_fierst + Ebrst_fierst
- L1_second*Evmd_second - L2_second*Eem_second - Ebrst_second);
if(q2_fierst < 4.0*ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(q2_second < 4.0*ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(k2_fierst < ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(k2_second < ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
} // End of the operator "for(i4=0;i4<2;i4++)"
} // End of the operator "for(i1=0;i1<2;i1++)"
} // End of the operator "for(i2=0;i2<2;i2++)"
} // End of the operator: "if (bmesons.contains(idparent))"
else { // Start of the operator "else N1"
// ++++++++++++++++++++++++++++++++++++++++++++++++++
// + Contribution for B+ decay +
// ++++++++++++++++++++++++++++++++++++++++++++++++++
if (bbarmesons.contains(idparent)){
Tvmd_fierst = 0.0*EvtTensor4C::g();
for(aa = 0; aa < 2; aa++){
EvtComplex coeff_vmd;
double Re_vmd, Im_vmd, znam_vmd;
Re_vmd = q2_fierst - M2[aa]*M2[aa];
Im_vmd = Width2[aa]*M2[aa];
znam_vmd = fV2[aa]*(Re_vmd*Re_vmd + Im_vmd*Im_vmd);
coeff_vmd = unit1*Re_vmd/znam_vmd - uniti*Im_vmd/znam_vmd;
double vaa, a2aa, a3aa;
vaa = 2.0*v[aa]/(M1 + M2[aa]);
a2aa = a2[aa]/(M1 + M2[aa]);
a3aa = 2.0*M2[aa]*(a3[aa] - a0[aa])/k2_fierst;
Tvmd_fierst = Tvmd_fierst
+coeff_vmd*(0.0*EvtTensor4C::g()
+unit1*vaa*dual(EvtGenFunctions::directProd(p,q_fierst))
-uniti*a1[aa]*(M1 + M2[aa])*EvtTensor4C::g()
+uniti*a2aa*EvtGenFunctions::directProd((p + q_fierst),p)
+uniti*a3aa*EvtGenFunctions::directProd((p - q_fierst),p));
}
Tvmd_second = 0.0*EvtTensor4C::g();
for(aa = 2; aa < 4; aa++){
EvtComplex coeff_vmd;
double Re_vmd, Im_vmd, znam_vmd;
Re_vmd = q2_second - M2[aa]*M2[aa];
Im_vmd = Width2[aa]*M2[aa];
znam_vmd = fV2[aa]*(Re_vmd*Re_vmd + Im_vmd*Im_vmd);
coeff_vmd = unit1*Re_vmd/znam_vmd - uniti*Im_vmd/znam_vmd;
double vaa, a2aa, a3aa;
vaa = 2.0*v[aa]/(M1 + M2[aa]);
a2aa = a2[aa]/(M1 + M2[aa]);
a3aa = 2.0*M2[aa]*(a3[aa] - a0[aa])/k2_second;
Tvmd_second = Tvmd_second
+coeff_vmd*(0.0*EvtTensor4C::g()
+unit1*vaa*dual(EvtGenFunctions::directProd(p,q_second))
-uniti*a1[aa]*(M1 + M2[aa])*EvtTensor4C::g()
+uniti*a2aa*EvtGenFunctions::directProd((p + q_second),p)
+uniti*a3aa*EvtGenFunctions::directProd((p - q_second),p));
}
Tem_fierst = 0.0*EvtTensor4C::g();
for(aa = 0; aa < 2; aa++){
double fBstar = 0.0 - 0.2; // GeV
double coeff;
coeff = fBstar/(q2_fierst*(k2_fierst - MBstar*MBstar));
Tem_fierst = Tem_fierst + coeff*v_em[aa]*dual(EvtGenFunctions::directProd(p,k_fierst));
}
Tem_second = 0.0*EvtTensor4C::g();
for(aa = 2; aa < 4; aa++){
double fBstar = 0.0 - 0.2; // GeV
double coeff;
coeff = fBstar/(q2_fierst*(k2_fierst - MBstar*MBstar));
Tem_second = Tem_second + coeff*v_em[aa]*dual(EvtGenFunctions::directProd(p,k_second));
}
// Amplitude calculation
for(i2=0;i2<2;i2++){
leptonicspin[0] = i2;
for(i1=0;i1<2;i1++){
leptonicspin[1] = i1;
for(i4=0;i4<2;i4++){
leptonicspin[2] = i4;
i3 = 0; // neutrino spin structure!
leptonicspin[3] = i3;
//(\bar nu(k_3) \gamma^{\mu} (1 - \gamma^5) mu(- k_4))
L1_fierst = EvtLeptonVACurrent(parent->getDaug(il3)->spParentNeutrino(),
parent->getDaug(il4)->spParent(i4));
//(\bar mu(k_1) \gamma^{\mu} mu(- k_2))
L2_fierst = EvtLeptonVCurrent(parent->getDaug(il1)->spParent(i1),
parent->getDaug(il2)->spParent(i2));
//(\bar nu(k_3) \gamma^{\mu} (1 - \gamma^5) mu(- k_2))
L1_second = EvtLeptonVACurrent(parent->getDaug(il3)->spParentNeutrino(),
parent->getDaug(il2)->spParent(i2));
//(\bar mu(k_1) \gamma^{\mu} mu(- k_4))
L2_second = EvtLeptonVCurrent(parent->getDaug(il1)->spParent(i1),
parent->getDaug(il4)->spParent(i4));
// VMD
EvtVector4C Evmd_fierst, Evmd_second;
Evmd_fierst=Tvmd_fierst.cont2(L2_fierst);
Evmd_second=Tvmd_second.cont2(L2_second);
// EM
EvtVector4C Eem_fierst, Eem_second;
Eem_fierst=Tem_fierst.cont2(L1_fierst);
Eem_second=Tem_second.cont2(L1_second);
// Bremsstrahlung
EvtComplex Ebrst_fierst, Ebrst_second;
double fB = 0.20; // GeV leptonic constant of B^{\pm} mesons
Ebrst_fierst = uniti*fB*L2_fierst*L1_fierst/q2_fierst;
Ebrst_second = uniti*fB*L2_second*L1_second/q2_second;
amp.vertex(leptonicspin, L1_fierst*Evmd_fierst + L2_fierst*Eem_fierst + Ebrst_fierst
- L1_second*Evmd_second - L2_second*Eem_second - Ebrst_second);
if(q2_fierst < 4.0*ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(q2_second < 4.0*ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(k2_fierst < ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
if(k2_second < ml*ml)
{
amp.vertex(leptonicspin, unit1*0.0);
}
} // End of the operator "for(i4=0;i4<2;i4++)"
} // End of the operator "for(i1=0;i1<2;i1++)"
} // End of the operator "for(i2=0;i2<2;i2++)"
} // End of the operator: "if (bbarmesons.contains(idparent))"
else{ // Start of the operator "else N2"
EvtGenReport(EVTGEN_ERROR,"EvtGen")
<< "\n\n The function EvtB2MuMuMuNuAmp::CalcAmp(...)"
<< "\n Wrong B-meson number"
<< "\n B-meson KF code = " << EvtPDL::getLundKC(parent->getId())
<< std::endl;
::abort();
} // End of the operator "else N2"
} // End of the operator "else N1"
}
EvtComplex EvtResonance2::resAmpl() {
double pi180inv = 1.0/EvtConst::radToDegrees;
EvtComplex ampl;
EvtVector4R p4_d3 = _p4_p-_p4_d1-_p4_d2;
//get cos of the angle between the daughters from their 4-momenta
//and the 4-momentum of the parent
//in general, EvtDecayAngle(parent, part1+part2, part1) gives the angle
//the missing particle (not listed in the arguments) makes
//with part2 in the rest frame of both
//listed particles (12)
//angle 3 makes with 2 in rest frame of 12 (CS3)
//double cos_phi_0 = EvtDecayAngle(_p4_p, _p4_d1+_p4_d2, _p4_d1);
//angle 3 makes with 1 in 12 is, of course, -cos_phi_0
//first compute several quantities...follow CLEO preprint 00-23
double mAB=(_p4_d1+_p4_d2).mass();
double mBC=(_p4_d2+p4_d3).mass();
double mAC=(_p4_d1+p4_d3).mass();
double mA=_p4_d1.mass();
double mB=_p4_d2.mass();
double mD=_p4_p.mass();
double mC=p4_d3.mass();
double mR=_bwm;
double gammaR=_gamma;
double mdenom = _invmass_angdenom ? mAB : mR;
double pAB=sqrt( (((mAB*mAB-mA*mA-mB*mB)*(mAB*mAB-mA*mA-mB*mB)/4.0) -
mA*mA*mB*mB)/(mAB*mAB));
double pR=sqrt( (((mR*mR-mA*mA-mB*mB)*(mR*mR-mA*mA-mB*mB)/4.0) -
mA*mA*mB*mB)/(mR*mR));
double pD= (((mD*mD-mR*mR-mC*mC)*(mD*mD-mR*mR-mC*mC)/4.0) -
mR*mR*mC*mC)/(mD*mD);
if ( pD>0 ) { pD=sqrt(pD); } else {pD=0;}
double pDAB=sqrt( (((mD*mD-mAB*mAB-mC*mC)*(mD*mD-mAB*mAB-mC*mC)/4.0) -
mAB*mAB*mC*mC)/(mD*mD));
double fR=1;
double fD=1;
int power=0;
switch (_spin) {
case 0:
fR=1.0;
fD=1.0;
power=1;
break;
case 1:
fR=sqrt(1.0+1.5*1.5*pR*pR)/sqrt(1.0+1.5*1.5*pAB*pAB);
fD=sqrt(1.0+5.0*5.0*pD*pD)/sqrt(1.0+5.0*5.0*pDAB*pDAB);
power=3;
break;
case 2:
fR = sqrt( (9+3*pow((1.5*pR),2)+pow((1.5*pR),4))/(9+3*pow((1.5*pAB),2)+pow((1.5*pAB),4)) );
fD = sqrt( (9+3*pow((5.0*pD),2)+pow((5.0*pD),4))/(9+3*pow((5.0*pDAB),2)+pow((5.0*pDAB),4)) );
power=5;
break;
default:
EvtGenReport(EVTGEN_INFO,"EvtGen") << "Incorrect spin in EvtResonance22.cc\n";
}
double gammaAB= gammaR*pow(pAB/pR,power)*(mR/mAB)*fR*fR;
switch (_spin) {
case 0:
ampl=_ampl*EvtComplex(cos(_theta*pi180inv),sin(_theta*pi180inv))*
fR*fD/(mR*mR-mAB*mAB-EvtComplex(0.0,mR*gammaAB));
break;
case 1:
ampl=_ampl*EvtComplex(cos(_theta*pi180inv),sin(_theta*pi180inv))*
(fR*fD*(mAC*mAC-mBC*mBC+((mD*mD-mC*mC)*(mB*mB-mA*mA)/(mdenom*mdenom)))/
(mR*mR-mAB*mAB-EvtComplex(0.0,mR*gammaAB)));
break;
case 2:
ampl=_ampl*EvtComplex(cos(_theta*pi180inv),sin(_theta*pi180inv))*
fR*fD/(mR*mR-mAB*mAB-EvtComplex(0.0,mR*gammaAB))*
(pow((mBC*mBC-mAC*mAC+(mD*mD-mC*mC)*(mA*mA-mB*mB)/(mdenom*mdenom)),2)-
(1.0/3.0)*(mAB*mAB-2*mD*mD-2*mC*mC+pow((mD*mD- mC*mC)/mdenom, 2))*
(mAB*mAB-2*mA*mA-2*mB*mB+pow((mA*mA-mB*mB)/mdenom,2)));
break;
default:
EvtGenReport(EVTGEN_INFO,"EvtGen") << "Incorrect spin in EvtResonance22.cc\n";
}
return ampl;
}
