BR_Bsnunu Class Reference

A class for the branching ratio of \(B_s\to \nu\nu\). More...

#include <BR_Bsnunu.h>

Inheritance diagram for BR_Bsnunu:

Detailed Description

A class for the branching ratio of \(B_s\to \nu\nu\).

Author

HEPfit Collaboration

Copyright

GNU General Public License

This class is used to compute the theoretical value of the branching ratio of \(B_s\to \nu\nu\).

Model parameters

The model parameters of BR_Bsnunu are summarized below:

Label	LaTeX symbol	Description
Br_B_Xcenu	\(\mathrm{BR}(B\to X_ce\nu)\)	The experimental value for the branching ratio of \(B\to X_c e\nu\).

Definition at line 45 of file BR_Bsnunu.h.

Public Member Functions
	BR_Bsnunu (StandardModel &SM_i)
	Constructor. More...
double	computeThValue ()
	hep-ph/9512380v2 More...
Public Member Functions inherited from ThObservable
double	getBinMax ()
	A get method to get the maximum value of the bin. More...
double	getBinMin ()
	A get method to get the minimum value of the bin. More...
const StandardModel &	getModel ()
	A get method to get the model. More...
const std::vector< std::string >	getParametersForObservable ()
	A get method to get the parameters for the specific observable. More...
void	setBinMax (double max)
	A set method to set the maximum value of the bin. More...
void	setBinMin (double min)
	A set method to set the minimum value of the bin. More...
void	setParametersForObservable (std::vector< std::string > parametersForObservable_i)
	A set method to get the parameters for the specific observable. More...
	ThObservable (const StandardModel &SM_i)
	Constructor. More...
	ThObservable (const ThObservable &orig)
	The copy constructor. More...
virtual	~ThObservable ()
	The default destructor. More...

Protected Member Functions
gslpp::complex	BRBsnunu (orders order)
	the short distance contribution to the | \( BR(B_d \rightarrow \nu \bar{\nu}) \)| More...

Private Attributes
StandardModel &	mySM

Additional Inherited Members
Protected Attributes inherited from ThObservable
double	max
	the bin maximum. More...
double	min
	The bin minimum. More...
std::vector< std::string >	parametersForObservable
	a vector of parameter namesfor the specific observable More...
const StandardModel &	SM
	A reference to an object of StandardMode class. More...

Constructor & Destructor Documentation

BR_Bsnunu()

BR_Bsnunu::BR_Bsnunu

(

StandardModel &

SM_i

)

Constructor.

Parameters

[in]

SM_i

a reference to an object of type StandardModel

Definition at line 13 of file BR_Bsnunu.cpp.

: ThObservable(SM_i), mySM(SM_i)
{
    setParametersForObservable(make_vector<std::string>() << "Br_B_Xcenu");
}

Member Function Documentation

BRBsnunu()

gslpp::complex BR_Bsnunu::BRBsnunu ( orders  order )

protected

the short distance contribution to the | \( BR(B_d \rightarrow \nu \bar{\nu}) \)|

Parameters

[in]

order

the QCD order of the computation

Definition at line 36 of file BR_Bsnunu.cpp.

{
    if (mySM.getFlavour().getHDB1().getCoeffsnunu().getOrder() < order){
        std::stringstream out;
        out << order;
        throw std::runtime_error("BRBsnunu::computeThValue(): requires cofficient of "
                                 "order" + out.str() + "not computed");
    }
    
    gslpp::vector<gslpp::complex> ** allcoeff = mySM.getFlavour().ComputeCoeffsnunu();
    
    switch(order) {
        case NLO:
                return((*(allcoeff[LO]) + *(allcoeff[NLO])) *
                       (*(allcoeff[LO]) + *(allcoeff[NLO])));
        case LO:
                return((*(allcoeff[LO])) *
                       (*(allcoeff[LO])));
        default:
            std::stringstream out;
            out << order;
            throw std::runtime_error("BRBsnunu::BRBsnunu(): order " + out.str() + "not implemented");;
    }
}

computeThValue()

double BR_Bsnunu::computeThValue ( )

virtual

hep-ph/9512380v2

Returns

theoretical value of | \( BR(B_s \rightarrow \nu \bar{\nu}) \)|

Implements ThObservable.

Definition at line 19 of file BR_Bsnunu.cpp.

{
    double theta= asin(sqrt( (M_PI * mySM.getAle() )/( sqrt(2) *
                  mySM.getGF() * mySM.Mw_tree() * 
                  mySM.Mw_tree()) ));
    
    double z = mySM.getQuarks(QCD::CHARM).getMass()/
               mySM.getQuarks(QCD::BOTTOM).getMass();
    
    
    return(3.*mySM.getAle()*mySM.getAle()/(4.*M_PI*M_PI*pow(sin(theta),4.)) * 
           mySM.getOptionalParameter("Br_B_Xcenu") *
           BRBsnunu(NLO).real() * (1.+2.*mySM.Als(mySM.getMub())/3./M_PI)*(25./4.-M_PI*M_PI)
           /(1. - 8.*z*z + 8.*z*z*z*z*z*z - z*z*z*z*z*z*z*z - 24.*z*z*z*z*log(z))
           /(1. - 2.*mySM.Als(mySM.getMub())/3./M_PI*((M_PI*M_PI-31./4.)*(1.-z*z)+1.5)));
}

Member Data Documentation

mySM

StandardModel& BR_Bsnunu::mySM

private

Definition at line 72 of file BR_Bsnunu.h.

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The documentation for this class was generated from the following files:

• BR_Bsnunu.h
• BR_Bsnunu.cpp