BR_Kp0nunu Class Reference

A class for the branching ratio of \(K_L\to\pi^0\nu\bar{\nu}\). More...

#include <BR_Kp0nunu.h>

Inheritance diagram for BR_Kp0nunu:

Detailed Description

A class for the branching ratio of \(K_L\to\pi^0\nu\bar{\nu}\).

Author

HEPfit Collaboration

Copyright

GNU General Public License

This class is used to compute the theoretical value of the branching ratio of \(K_L\to\pi^0\nu\bar{\nu}\).

Model parameters

The model parameters of BR_Kp0nunu are summarized below:

Label	LaTeX symbol	Description
Br_Kp_P0enu	\(\mathrm{BR}(K^+\to\pi^0e^+\nu)\)	The experimental value for the branching ratio of \(K^+\to\pi^0e^+\nu\).
IB_Kl	\(\)	the isospin breaking corrections between \(K_L\to\pi^0\nu\bar{\nu}\) and \(K^+\to\pi^0 e^+\nu\).

Definition at line 52 of file BR_Kp0nunu.h.

Public Member Functions
	BR_Kp0nunu (StandardModel &SM_i)
double	computeThValue ()
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	BRKp0nunu (orders order, orders_qed order_qed)

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_Kp0nunu()

BR_Kp0nunu::BR_Kp0nunu

(

StandardModel &

SM_i

)

constructor

Parameters

Flavour

Definition at line 13 of file BR_Kp0nunu.cpp.

: ThObservable(SM_i), mySM(SM_i)
{
    setParametersForObservable(make_vector<std::string>() << "Br_Kp_P0enu" << "IB_Kl");
    mySM.initializeMeson(QCD::K_0);
    mySM.initializeMeson(QCD::K_P);
}

Member Function Documentation

BRKp0nunu()

gslpp::complex BR_Kp0nunu::BRKp0nunu ( orders  order, orders_qed  order_qed  )

protected

Parameters

order
order_qed

Returns

the short distance contribution to the \( BR(K_{L} \rightarrow \pi^{0} \nu \bar{\nu}) \), for example see hep-ph/0603079 section 2.3

Definition at line 31 of file BR_Kp0nunu.cpp.

{
    if (mySM.getFlavour().getHDS1().getCoeffDS1pnunu().getOrder() < order){
        std::stringstream out;
        out << order;
        throw std::runtime_error("BRKp0nunu::computeThValue(): requires cofficient of "
                                 "order" + out.str() + "not computed");
    }
    
    gslpp::vector<gslpp::complex> ** allcoeff = mySM.getFlavour().ComputeCoeffDS1pnunu();
    
    switch(order_qed) {
        case NLO_QED11:
            return((*(allcoeff[LO]) + *(allcoeff[NLO]) + *(allcoeff[NLO_QED11])) *
                   (*(allcoeff[LO]) + *(allcoeff[NLO]) + *(allcoeff[NLO_QED11])));
        case LO_QED:
            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("BRKp0nunu::BRKp0nunu(): order " + out.str() + "not implemented");
            }
         default:
            std::stringstream out;
            out << order_qed;
            throw std::runtime_error("BRKp0nunu::BRKp0nunu(): order_qed " + out.str() + "not implemented");
    }
}

computeThValue()

double BR_Kp0nunu::computeThValue ( )

virtual

Returns

theoretical value of \( BR(K_L \rightarrow \pi^{0} \nu \bar{\nu}) \), for example see hep-ph/0603079 section 2.3

Implements ThObservable.

Definition at line 21 of file BR_Kp0nunu.cpp.

{
    double theta = asin(sqrt( (M_PI * SM.getAle() )/( sqrt(2) * SM.getGF() * 
                   SM.Mw_tree() * SM.Mw_tree()) ));
    
    return(SM.getOptionalParameter("IB_Kl") * (SM.getMesons(QCD::K_0).getLifetime() / HCUT / SM.getMesons(QCD::K_P).getLifetime() / HCUT)
           * 3. * SM.getAle() * SM.getAle() / (2.*M_PI*M_PI*pow(sin(theta),4.)) * SM.getOptionalParameter("Br_Kp_P0enu") *
           BRKp0nunu(NLO, NLO_QED11).real());
}

Member Data Documentation

mySM

StandardModel& BR_Kp0nunu::mySM

private

Definition at line 82 of file BR_Kp0nunu.h.

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

• BR_Kp0nunu.h
• BR_Kp0nunu.cpp