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	diff --git a/Decay/Perturbative/SMWDecayer.cc b/Decay/Perturbative/SMWDecayer.cc
	--- a/Decay/Perturbative/SMWDecayer.cc
	+++ b/Decay/Perturbative/SMWDecayer.cc
	@@ -1,742 +1,740 @@
	// -- C++ --
	//
	// SMWDecayer.cc is a part of Herwig - A multi-purpose Monte Carlo event generator
	// Copyright (C) 2002-2017 The Herwig Collaboration
	//
	// Herwig is licenced under version 3 of the GPL, see COPYING for details.
	// Please respect the MCnet academic guidelines, see GUIDELINES for details.
	//
	//
	// This is the implementation of the non-inlined, non-templated member
	// functions of the SMWDecayer class.
	//

	#include "SMWDecayer.h"
	#include "ThePEG/Utilities/DescribeClass.h"
	#include "ThePEG/Interface/ClassDocumentation.h"
	#include "ThePEG/Interface/ParVector.h"
	#include "ThePEG/Interface/Reference.h"
	#include "ThePEG/Interface/Switch.h"
	#include "ThePEG/Persistency/PersistentOStream.h"
	#include "ThePEG/Persistency/PersistentIStream.h"
	#include "ThePEG/PDT/DecayMode.h"
	#include "Herwig/Decay/DecayVertex.h"
	#include "ThePEG/Helicity/VectorSpinInfo.h"
	#include "ThePEG/Helicity/FermionSpinInfo.h"
	#include "ThePEG/Helicity/WaveFunction/VectorWaveFunction.h"
	#include "Herwig/Models/StandardModel/StandardModel.h"
	#include "Herwig/Shower/RealEmissionProcess.h"
	#include "Herwig/Decay/GeneralDecayMatrixElement.h"
	#include <numeric>

	using namespace Herwig;
	using namespace ThePEG::Helicity;

	const double SMWDecayer::EPS_=0.00000001;

	SMWDecayer::SMWDecayer()
	: quarkWeight_(6,0.), leptonWeight_(3,0.), CF_(4./3.),
	NLO_(false) {
	quarkWeight_[0] = 1.01596;
	quarkWeight_[1] = 0.0537308;
	quarkWeight_[2] = 0.0538085;
	quarkWeight_[3] = 1.01377;
	quarkWeight_[4] = 1.45763e-05;
	quarkWeight_[5] = 0.0018143;
	leptonWeight_[0] = 0.356594;
	leptonWeight_[1] = 0.356593;
	leptonWeight_[2] = 0.356333;
	// intermediates
	generateIntermediates(false);
	}

	void SMWDecayer::doinit() {
	- PerturbativeDecayer::doinit();
	+ PerturbativeDecayer2::doinit();
	// get the vertices from the Standard Model object
	tcHwSMPtr hwsm=dynamic_ptr_cast<tcHwSMPtr>(standardModel());
	if(!hwsm) throw InitException() << "Must have Herwig StandardModel object in"
	<< "SMWDecayer::doinit()"
	<< Exception::runerror;
	FFWVertex_ = hwsm->vertexFFW();
	FFGVertex_ = hwsm->vertexFFG();
	WWWVertex_ = hwsm->vertexWWW();
	FFPVertex_ = hwsm->vertexFFP();
	// make sure they are initialized
	FFGVertex_->init();
	FFWVertex_->init();
	WWWVertex_->init();
	FFPVertex_->init();
	// now set up the decay modes
	- DecayPhaseSpaceModePtr mode;
	- tPDVector extpart(3);
	- vector<double> wgt(0);
	// W modes
	- extpart[0]=getParticleData(ParticleID::Wplus);
	+ tPDPtr Wp = getParticleData(ParticleID::Wplus);
	// loop for the quarks
	unsigned int iz=0;
	for(int ix=1;ix<6;ix+=2) {
	for(int iy=2;iy<6;iy+=2) {
	// check that the combination of particles is allowed
	if(!FFWVertex_->allowed(-ix,iy,ParticleID::Wminus))
	throw InitException() << "SMWDecayer::doinit() the W vertex"
	<< "cannot handle all the quark modes"
	<< Exception::abortnow;
	- extpart[1] = getParticleData(-ix);
	- extpart[2] = getParticleData( iy);
	- mode = new_ptr(DecayPhaseSpaceMode(extpart,this));
	- addMode(mode,quarkWeight_[iz],wgt);
	+ tPDVector out = {getParticleData(-ix),
	+ getParticleData( iy)};
	+ PhaseSpaceModePtr mode = new_ptr(PhaseSpaceMode(Wp,out,quarkWeight_[iz]));
	+ addMode(mode);
	++iz;
	}
	}
	// loop for the leptons
	for(int ix=11;ix<17;ix+=2) {
	- // check that the combination of particles is allowed
	- // if(!FFWVertex_->allowed(-ix,ix+1,ParticleID::Wminus))
	- // throw InitException() << "SMWDecayer::doinit() the W vertex"
	- // << "cannot handle all the lepton modes"
	- // << Exception::abortnow;
	- extpart[1] = getParticleData(-ix);
	- extpart[2] = getParticleData(ix+1);
	- mode = new_ptr(DecayPhaseSpaceMode(extpart,this));
	- addMode(mode,leptonWeight_[(ix-11)/2],wgt);
	+ tPDVector out = {getParticleData(-ix ),
	+ getParticleData( ix+1)};
	+ PhaseSpaceModePtr mode = new_ptr(PhaseSpaceMode(Wp,out,leptonWeight_[(ix-11)/2]));
	+ addMode(mode);
	}
	gluon_ = getParticleData(ParticleID::g);
	}

	int SMWDecayer::modeNumber(bool & cc,tcPDPtr parent,
	const tPDVector & children) const {
	int imode(-1);
	if(children.size()!=2) return imode;
	int id0=parent->id();
	tPDVector::const_iterator pit = children.begin();
	int id1=(**pit).id();
	++pit;
	int id2=(**pit).id();
	if(abs(id0)!=ParticleID::Wplus) return imode;
	int idd(0),idu(0);
	if(abs(id1)%2==1&&abs(id2)%2==0) {
	idd=abs(id1);
	idu=abs(id2);
	}
	else if(abs(id1)%2==0&&abs(id2)%2==1) {
	idd=abs(id2);
	idu=abs(id1);
	}
	if(idd==0&&idu==0) {
	return imode;
	}
	else if(idd<=5) {
	imode=idd+idu/2-2;
	}
	else {
	imode=(idd-1)/2+1;
	}
	cc= (id0==ParticleID::Wminus);
	return imode;
	}

	+ParticleVector SMWDecayer::decay(const Particle & parent,
	+ const tPDVector & children) const {
	+ // generate the decay
	+ bool cc;
	+ unsigned int imode = modeNumber(cc,parent.dataPtr(),children);
	+ ParticleVector output = generate(false,false,imode,parent);
	+ if(output[0]->hasColour()) output[0]->antiColourNeighbour(output[1]);
	+ else if(output[1]->hasColour()) output[1]->antiColourNeighbour(output[0]);
	+ return output;
	+}
	+
	void SMWDecayer::persistentOutput(PersistentOStream & os) const {
	os << FFWVertex_ << quarkWeight_ << leptonWeight_
	<< FFGVertex_ << gluon_ << NLO_
	<< WWWVertex_ << FFPVertex_;
	}

	void SMWDecayer::persistentInput(PersistentIStream & is, int) {
	is >> FFWVertex_ >> quarkWeight_ >> leptonWeight_
	>> FFGVertex_ >> gluon_ >> NLO_
	>> WWWVertex_ >> FFPVertex_;
	}

	// The following static variable is needed for the type
	// description system in ThePEG.
	-DescribeClass<SMWDecayer,PerturbativeDecayer>
	+DescribeClass<SMWDecayer,PerturbativeDecayer2>
	describeHerwigSMWDecayer("Herwig::SMWDecayer", "HwPerturbativeDecay.so");

	void SMWDecayer::Init() {

	static ClassDocumentation<SMWDecayer> documentation
	("The SMWDecayer class is the implementation of the decay"
	" of the W boson to the Standard Model fermions.");

	static ParVector<SMWDecayer,double> interfaceWquarkMax
	("QuarkMax",
	"The maximum weight for the decay of the W to quarks",
	&SMWDecayer::quarkWeight_,
	0, 0, 0, -10000, 10000, false, false, true);

	static ParVector<SMWDecayer,double> interfaceWleptonMax
	("LeptonMax",
	"The maximum weight for the decay of the W to leptons",
	&SMWDecayer::leptonWeight_,
	0, 0, 0, -10000, 10000, false, false, true);

	static Switch<SMWDecayer,bool> interfaceNLO
	("NLO",
	"Whether to return the LO or NLO result",
	&SMWDecayer::NLO_, false, false, false);
	static SwitchOption interfaceNLOLO
	(interfaceNLO,
	"No",
	"Leading-order result",
	false);
	static SwitchOption interfaceNLONLO
	(interfaceNLO,
	"Yes",
	"NLO result",
	true);

	}
	-
	+void SMWDecayer::
	+constructSpinInfo(const Particle & part, ParticleVector decay) const {
	+ int iferm(1),ianti(0);
	+ if(decay[0]->id()>0) swap(iferm,ianti);
	+ VectorWaveFunction::constructSpinInfo(vectors_,const_ptr_cast<tPPtr>(&part),
	+ incoming,true,false);
	+ SpinorBarWaveFunction::
	+ constructSpinInfo(wavebar_,decay[iferm],outgoing,true);
	+ SpinorWaveFunction::
	+ constructSpinInfo(wave_ ,decay[ianti],outgoing,true);
	+}

	// return the matrix element squared
	-double SMWDecayer::me2(const int, const Particle & part,
	- const ParticleVector & decay,
	- MEOption meopt) const {
	+double SMWDecayer::me2(const int,const Particle & part,
	+ const tPDVector & outgoing,
	+ const vector<Lorentz5Momentum> & momenta,
	+ MEOption meopt) const {
	if(!ME())
	ME(new_ptr(GeneralDecayMatrixElement(PDT::Spin1,PDT::Spin1Half,PDT::Spin1Half)));
	int iferm(1),ianti(0);
	- if(decay[0]->id()>0) swap(iferm,ianti);
	+ if(outgoing[0]->id()>0) swap(iferm,ianti);
	if(meopt==Initialize) {
	VectorWaveFunction::calculateWaveFunctions(vectors_,rho_,
	- const_ptr_cast<tPPtr>(&part),
	- incoming,false);
	+ const_ptr_cast<tPPtr>(&part),
	+ incoming,false);
	// fix rho if no correlations
	fixRho(rho_);
	}
	- if(meopt==Terminate) {
	- VectorWaveFunction::constructSpinInfo(vectors_,const_ptr_cast<tPPtr>(&part),
	- incoming,true,false);
	- SpinorBarWaveFunction::
	- constructSpinInfo(wavebar_,decay[iferm],outgoing,true);
	- SpinorWaveFunction::
	- constructSpinInfo(wave_ ,decay[ianti],outgoing,true);
	- return 0.;
	+ SpinorBarWaveFunction wbar(momenta[iferm],outgoing[iferm],Helicity::outgoing);
	+ SpinorWaveFunction w (momenta[ianti],outgoing[ianti],Helicity::outgoing);
	+ wavebar_.resize(2);
	+ wave_ .resize(2);
	+ for(unsigned int ihel=0;ihel<2;++ihel) {
	+ wbar.reset(ihel);
	+ wavebar_[ihel] = wbar;
	+ w.reset(ihel);
	+ wave_ [ihel] = w;
	}
	- SpinorBarWaveFunction::
	- calculateWaveFunctions(wavebar_,decay[iferm],outgoing);
	- SpinorWaveFunction::
	- calculateWaveFunctions(wave_ ,decay[ianti],outgoing);
	// compute the matrix element
	Energy2 scale(sqr(part.mass()));
	for(unsigned int ifm=0;ifm<2;++ifm) {
	for(unsigned int ia=0;ia<2;++ia) {
	for(unsigned int vhel=0;vhel<3;++vhel) {
	- if(iferm>ianti) (*ME())(vhel,ia,ifm)=
	- FFWVertex_->evaluate(scale,wave_[ia],wavebar_[ifm],vectors_[vhel]);
	- else (*ME())(vhel,ifm,ia)=
	- FFWVertex_->evaluate(scale,wave_[ia],wavebar_[ifm],vectors_[vhel]);
	+ if(iferm>ianti) (*ME())(vhel,ia,ifm)=
	+ FFWVertex_->evaluate(scale,wave_[ia],wavebar_[ifm],vectors_[vhel]);
	+ else (*ME())(vhel,ifm,ia)=
	+ FFWVertex_->evaluate(scale,wave_[ia],wavebar_[ifm],vectors_[vhel]);
	}
	}
	}
	double output=(ME()->contract(rho_)).real()*UnitRemoval::E2/scale;
	- if(abs(decay[0]->id())<=6) output*=3.;
	- if(decay[0]->hasColour()) decay[0]->antiColourNeighbour(decay[1]);
	- else if(decay[1]->hasColour()) decay[1]->antiColourNeighbour(decay[0]);
	- // leading-order result
	+ if(abs(outgoing[0]->id())<=6) output*=3.;
	+ // // leading-order result
	if(!NLO_) return output;
	// check decay products coloured, otherwise return
	- if(!decay[0]->dataPtr()->coloured()) return output;
	+ if(!outgoing[0]->coloured()) return output;
	// inital masses, couplings etc
	// W mass
	mW_ = part.mass();
	// strong coupling
	aS_ = SM().alphaS(sqr(mW_));
	// reduced mass
	- double mu1 = (decay[0]->dataPtr()->mass())/mW_;
	- double mu2 = (decay[1]->dataPtr()->mass())/mW_;
	+ double mu1 = outgoing[0]->mass()/mW_;
	+ double mu2 = outgoing[1]->mass()/mW_;
	// scale
	scale_ = sqr(mW_);
	// now for the nlo loop correction
	double virt = CF_*aS_/Constants::pi;
	// now for the real correction
	double realFact=0.;
	for(int iemit=0;iemit<2;++iemit) {
	double phi = UseRandom::rnd()*Constants::twopi;
	// set the emitter and the spectator
	double muj = iemit==0 ? mu1 : mu2;
	double muk = iemit==0 ? mu2 : mu1;
	double muj2 = sqr(muj);
	double muk2 = sqr(muk);
	// calculate y
	double yminus = 0.;
	double yplus = 1.-2.muk(1.-muk)/(1.-muj2-muk2);
	double y = yminus + UseRandom::rnd()*(yplus-yminus);
	double v = sqrt(sqr(2.muk2 + (1.-muj2-muk2)(1.-y))-4.*muk2)
	/(1.-muj2-muk2)/(1.-y);
	double zplus = (1.+v)(1.-muj2-muk2)y/2./(muj2+(1.-muj2-muk2)*y);
	double zminus = (1.-v)(1.-muj2-muk2)y/2./(muj2+(1.-muj2-muk2)*y);
	double z = zminus + UseRandom::rnd()*(zplus-zminus);
	double jac = (1.-y)(yplus-yminus)(zplus-zminus);
	// calculate x1,x2,x3,xT
	double x2 = 1.-y*(1.-muj2-muk2)-muj2+muk2;
	double x1 = 1.+muj2-muk2-z(x2-2.muk2);
	// copy the particle objects over for calculateRealEmission
	- vector<PPtr> hardProcess(3);
	- hardProcess[0] = const_ptr_cast<PPtr>(&part);
	- hardProcess[1] = decay[0];
	- hardProcess[2] = decay[1];
	+ tcPDVector outgoing = {part.dataPtr(),outgoing[0],outgoing[1],gluon_};
	+ vector<Lorentz5Momentum> momenta = {part.momentum(),momenta[0],momenta[1]};
	realFact += 0.25jacsqr(1.-muj2-muk2)/
	sqrt((1.-sqr(muj-muk))*(1.-sqr(muj+muk)))/Constants::twopi
	- 2.CF_aS_calculateRealEmission(x1, x2, hardProcess, phi,
	- muj, muk, iemit, true);
	+ 2.CF_aS_calculateRealEmission(x1, x2, outgoing,momenta, phi,
	+ muj, muk, iemit, true);
	}
	// the born + virtual + real
	output *= (1. + virt + realFact);
	return output;
	}

	void SMWDecayer::doinitrun() {
	- PerturbativeDecayer::doinitrun();
	+ PerturbativeDecayer2::doinitrun();
	if(initialize()) {
	for(unsigned int ix=0;ix<numberModes();++ix) {
	if(ix<6) quarkWeight_ [ix]=mode(ix)->maxWeight();
	else leptonWeight_[ix-6]=mode(ix)->maxWeight();
	}
	}
	}

	void SMWDecayer::dataBaseOutput(ofstream & output,
	bool header) const {
	if(header) output << "update decayers set parameters=\"";
	for(unsigned int ix=0;ix<quarkWeight_.size();++ix) {
	output << "newdef " << name() << ":QuarkMax " << ix << " "
	<< quarkWeight_[ix] << "\n";
	}
	for(unsigned int ix=0;ix<leptonWeight_.size();++ix) {
	output << "newdef " << name() << ":LeptonMax " << ix << " "
	<< leptonWeight_[ix] << "\n";
	}
	- // parameters for the PerturbativeDecayer base class
	- PerturbativeDecayer::dataBaseOutput(output,false);
	+ // parameters for the PerturbativeDecayer2 base class
	+ PerturbativeDecayer2::dataBaseOutput(output,false);
	if(header) output << "\n\" where BINARY ThePEGName=\""
	<< fullName() << "\";" << endl;
	}


	void SMWDecayer::
	initializeMECorrection(RealEmissionProcessPtr born, double & initial,
	double & final) {
	// get the quark and antiquark
	ParticleVector qq;
	for(unsigned int ix=0;ix<born->bornOutgoing().size();++ix)
	qq.push_back(born->bornOutgoing()[ix]);
	// ensure quark first
	if(qq[0]->id()<0) swap(qq[0],qq[1]);
	// centre of mass energy
	d_Q_ = (qq[0]->momentum() + qq[1]->momentum()).m();
	// quark mass
	d_m_ = 0.5*(qq[0]->momentum().m()+qq[1]->momentum().m());
	// set the other parameters
	setRho(sqr(d_m_/d_Q_));
	setKtildeSymm();
	// otherwise can do it
	initial=1.;
	final =1.;
	}

	bool SMWDecayer::softMatrixElementVeto(PPtr parent,
	PPtr progenitor,
	const bool & ,
	const Energy & highestpT,
	const vector<tcPDPtr> & ids,
	const double & d_z,
	const Energy & d_qt,
	const Energy & ) {
	// check we should be applying the veto
	if(parent->id()!=progenitor->id()\|\|
	ids[0]!=ids[1]\|\|
	ids[2]->id()!=ParticleID::g) return false;
	// calculate pt
	Energy2 d_m2 = parent->momentum().m2();
	Energy2 pPerp2 = sqr(d_z*d_qt) - d_m2;
	if(pPerp2<ZERO) return true;
	Energy pPerp = (1.-d_z)*sqrt(pPerp2);
	// if not hardest so far don't apply veto
	if(pPerp<highestpT) return false;
	// calculate the weight
	double weight = 0.;
	if(parent->id()>0) weight = qWeightX(d_qt, d_z);
	else weight = qbarWeightX(d_qt, d_z);
	// compute veto from weight and return
	return !UseRandom::rndbool(weight);
	}


	void SMWDecayer::setRho(double r)
	{
	d_rho_ = r;
	d_v_ = sqrt(1.-4.*d_rho_);
	}

	void SMWDecayer::setKtildeSymm() {
	d_kt1_ = (1. + sqrt(1. - 4.*d_rho_))/2.;
	setKtilde2();
	}

	void SMWDecayer::setKtilde2() {
	double num = d_rho_ * d_kt1_ + 0.25 * d_v_ (1.+d_v_)(1.+d_v_);
	double den = d_kt1_ - d_rho_;
	d_kt2_ = num/den;
	}

	double SMWDecayer::getZfromX(double x1, double x2) {
	double uval = u(x2);
	double num = x1 - (2. - x2)*uval;
	double den = sqrt(x2x2 - 4.d_rho_);
	return uval + num/den;
	}

	double SMWDecayer::getKfromX(double x1, double x2) {
	double zval = getZfromX(x1, x2);
	return (1.-x2)/(zval*(1.-zval));
	}

	double SMWDecayer::MEV(double x1, double x2) {
	// Vector part
	double num = (x1+2.d_rho_)(x1+2.d_rho_) + (x2+2.d_rho_)(x2+2.d_rho_)
	- 8.d_rho_(1.+2.*d_rho_);
	double den = (1.+2.d_rho_)(1.-x1)*(1.-x2);
	return (num/den - 2.d_rho_/((1.-x1)(1.-x1))
	- 2d_rho_/((1.-x2)(1.-x2)))/d_v_;
	}

	double SMWDecayer::MEA(double x1, double x2) {
	// Axial part
	double num = (x1+2.d_rho_)(x1+2.d_rho_) + (x2+2.d_rho_)(x2+2.d_rho_)
	+ 2.d_rho_((5.-x1-x2)(5.-x1-x2) - 19.0 + 4d_rho_);
	double den = d_v_d_v_(1.-x1)*(1.-x2);
	return (num/den - 2.d_rho_/((1.-x1)(1.-x1))
	- 2d_rho_/((1.-x2)(1.-x2)))/d_v_;
	}

	double SMWDecayer::u(double x2) {
	return 0.5*(1. + d_rho_/(1.-x2+d_rho_));
	}

	void SMWDecayer::
	getXXbar(double kti, double z, double &x, double &xbar) {
	double w = sqr(d_v_) + kti(-1. + z)z(2. + kti(-1. + z)*z);
	if (w < 0) {
	x = -1.;
	xbar = -1;
	} else {
	x = (1. + sqr(d_v_)(-1. + z) + sqr(kti(-1. + z))zz*z
	+ z*sqrt(w)
	- kti(-1. + z)z(2. + z(-2 + sqrt(w))))/
	(1. - kti(-1. + z)z + sqrt(w));
	xbar = 1. + kti(-1. + z)z;
	}
	}

	double SMWDecayer::qWeight(double x, double xbar) {
	double rval;
	double xg = 2. - xbar - x;
	// always return one in the soft gluon region
	if(xg < EPS_) return 1.0;
	// check it is in the phase space
	if((1.-x)(1.-xbar)(1.-xg) < d_rho_xgxg) return 0.0;
	double k1 = getKfromX(x, xbar);
	double k2 = getKfromX(xbar, x);
	// Is it in the quark emission zone?
	if(k1 < d_kt1_) {
	rval = MEV(x, xbar)/PS(x, xbar);
	// is it also in the anti-quark emission zone?
	if(k2 < d_kt2_) rval *= 0.5;
	return rval;
	}
	return 1.0;
	}

	double SMWDecayer::qbarWeight(double x, double xbar) {
	double rval;
	double xg = 2. - xbar - x;
	// always return one in the soft gluon region
	if(xg < EPS_) return 1.0;
	// check it is in the phase space
	if((1.-x)(1.-xbar)(1.-xg) < d_rho_xgxg) return 0.0;
	double k1 = getKfromX(x, xbar);
	double k2 = getKfromX(xbar, x);
	// Is it in the antiquark emission zone?
	if(k2 < d_kt2_) {
	rval = MEV(x, xbar)/PS(xbar, x);
	// is it also in the quark emission zone?
	if(k1 < d_kt1_) rval *= 0.5;
	return rval;
	}
	return 1.0;
	}

	double SMWDecayer::qWeightX(Energy qtilde, double z) {
	double x, xb;
	getXXbar(sqr(qtilde/d_Q_), z, x, xb);
	// if exceptionally out of phase space, leave this emission, as there
	// is no good interpretation for the soft ME correction.
	if (x < 0 \|\| xb < 0) return 1.0;
	return qWeight(x, xb);
	}

	double SMWDecayer::qbarWeightX(Energy qtilde, double z) {
	double x, xb;
	getXXbar(sqr(qtilde/d_Q_), z, xb, x);
	// see above in qWeightX.
	if (x < 0 \|\| xb < 0) return 1.0;
	return qbarWeight(x, xb);
	}

	double SMWDecayer::PS(double x, double xbar) {
	double u = 0.5*(1. + d_rho_ / (1.-xbar+d_rho_));
	double z = u + (x - (2.-xbar)u)/sqrt(xbarxbar - 4.*d_rho_);
	double brack = (1.+zz)/(1.-z)- 2.d_rho_/(1-xbar);
	// interesting: the splitting function without the subtraction
	// term. Actually gives a much worse approximation in the collinear
	// limit. double brack = (1.+z*z)/(1.-z);
	double den = (1.-xbar)sqrt(xbarxbar - 4.*d_rho_);
	return brack/den;
	}

	double SMWDecayer::matrixElementRatio(const Particle & inpart, const ParticleVector & decay2,
	const ParticleVector & decay3, MEOption,
	ShowerInteraction inter) {
	// extract partons and LO momentas
	- vector<cPDPtr> partons(1,inpart.dataPtr());
	+ vector<tcPDPtr> partons(1,inpart.dataPtr());
	vector<Lorentz5Momentum> lomom(1,inpart.momentum());
	for(unsigned int ix=0;ix<2;++ix) {
	partons.push_back(decay2[ix]->dataPtr());
	lomom.push_back(decay2[ix]->momentum());
	}
	vector<Lorentz5Momentum> realmom(1,inpart.momentum());
	for(unsigned int ix=0;ix<3;++ix) {
	if(ix==2) partons.push_back(decay3[ix]->dataPtr());
	realmom.push_back(decay3[ix]->momentum());
	}
	if(partons[0]->id()<0) {
	swap(partons[1],partons[2]);
	swap(lomom[1],lomom[2]);
	swap(realmom[1],realmom[2]);
	}
	scale_ = sqr(inpart.mass());
	double lome = loME(partons,lomom);
	InvEnergy2 reme = realME(partons,realmom,inter);
	double ratio = reme/lomesqr(inpart.mass())4.*Constants::pi;
	if(inter==ShowerInteraction::QCD) ratio *= CF_;
	return ratio;
	}

	-double SMWDecayer::meRatio(vector<cPDPtr> partons,
	+double SMWDecayer::meRatio(tcPDVector partons,
	vector<Lorentz5Momentum> momenta,
	unsigned int iemitter, bool subtract) const {
	Lorentz5Momentum q = momenta[1]+momenta[2]+momenta[3];
	Energy2 Q2=q.m2();
	Energy2 lambda = sqrt((Q2-sqr(momenta[1].mass()+momenta[2].mass()))*
	(Q2-sqr(momenta[1].mass()-momenta[2].mass())));
	InvEnergy2 D[2];
	double lome(0.);
	for(unsigned int iemit=0;iemit<2;++iemit) {
	unsigned int ispect = iemit==0 ? 1 : 0;
	Energy2 pipj = momenta[3 ] * momenta[1+iemit ];
	Energy2 pipk = momenta[3 ] * momenta[1+ispect];
	Energy2 pjpk = momenta[1+iemit] * momenta[1+ispect];
	double y = pipj/(pipj+pipk+pjpk);
	double z = pipk/( pipk+pjpk);
	Energy mij = sqrt(2.*pipj+sqr(momenta[1+iemit].mass()));
	Energy2 lamB = sqrt((Q2-sqr(mij+momenta[1+ispect].mass()))*
	(Q2-sqr(mij-momenta[1+ispect].mass())));
	Energy2 Qpk = q*momenta[1+ispect];
	Lorentz5Momentum pkt =
	lambda/lamB(momenta[1+ispect]-Qpk/Q2q)
	+0.5/Q2(Q2+sqr(momenta[1+ispect].mass())-sqr(momenta[1+ispect].mass()))q;
	Lorentz5Momentum pijt =
	q-pkt;
	double muj = momenta[1+iemit ].mass()/sqrt(Q2);
	double muk = momenta[1+ispect].mass()/sqrt(Q2);
	double vt = sqrt((1.-sqr(muj+muk))*(1.-sqr(muj-muk)))/(1.-sqr(muj)-sqr(muk));
	double v = sqrt(sqr(2.sqr(muk)+(1.-sqr(muj)-sqr(muk))(1.-y))-4.*sqr(muk))
	/(1.-y)/(1.-sqr(muj)-sqr(muk));
	// dipole term
	D[iemit] = 0.5/pipj(2./(1.-(1.-z)(1.-y))
	-vt/v*(2.-z+sqr(momenta[1+iemit].mass())/pipj));
	// matrix element
	vector<Lorentz5Momentum> lomom(3);
	lomom[0] = momenta[0];
	if(iemit==0) {
	lomom[1] = pijt;
	lomom[2] = pkt ;
	}
	else {
	lomom[2] = pijt;
	lomom[1] = pkt ;
	}
	if(iemit==0) lome = loME(partons,lomom);
	}
	InvEnergy2 ratio = realME(partons,momenta,ShowerInteraction::QCD)/lome*abs(D[iemitter])
	/(abs(D[0])+abs(D[1]));
	if(subtract)
	return Q2(ratio-2.D[iemitter]);
	else
	return Q2*ratio;
	}

	-double SMWDecayer::loME(const vector<cPDPtr> & partons,
	+double SMWDecayer::loME(const vector<tcPDPtr> & partons,
	const vector<Lorentz5Momentum> & momenta) const {
	// compute the spinors
	vector<VectorWaveFunction> vin;
	vector<SpinorWaveFunction> aout;
	vector<SpinorBarWaveFunction> fout;
	VectorWaveFunction win (momenta[0],partons[0],incoming);
	SpinorBarWaveFunction qkout(momenta[1],partons[1],outgoing);
	SpinorWaveFunction qbout(momenta[2],partons[2],outgoing);
	for(unsigned int ix=0;ix<2;++ix){
	qkout.reset(ix);
	fout.push_back(qkout);
	qbout.reset(ix);
	aout.push_back(qbout);
	}
	for(unsigned int ix=0;ix<3;++ix){
	win.reset(ix);
	vin.push_back(win);
	}
	// temporary storage of the different diagrams
	// sum over helicities to get the matrix element
	double total(0.);
	for(unsigned int inhel=0;inhel<3;++inhel) {
	for(unsigned int outhel1=0;outhel1<2;++outhel1) {
	for(unsigned int outhel2=0;outhel2<2;++outhel2) {
	Complex diag1 = FFWVertex_->evaluate(scale_,aout[outhel2],fout[outhel1],vin[inhel]);
	total += norm(diag1);
	}
	}
	}
	// return the answer
	return total;
	}

	-InvEnergy2 SMWDecayer::realME(const vector<cPDPtr> & partons,
	+InvEnergy2 SMWDecayer::realME(const vector<tcPDPtr> & partons,
	const vector<Lorentz5Momentum> & momenta,
	ShowerInteraction inter) const {
	// compute the spinors
	vector<VectorWaveFunction> vin;
	vector<SpinorWaveFunction> aout;
	vector<SpinorBarWaveFunction> fout;
	vector<VectorWaveFunction> gout;
	VectorWaveFunction win (momenta[0],partons[0],incoming);
	SpinorBarWaveFunction qkout(momenta[1],partons[1],outgoing);
	SpinorWaveFunction qbout(momenta[2],partons[2],outgoing);
	VectorWaveFunction gluon(momenta[3],partons[3],outgoing);
	for(unsigned int ix=0;ix<2;++ix){
	qkout.reset(ix);
	fout.push_back(qkout);
	qbout.reset(ix);
	aout.push_back(qbout);
	gluon.reset(2*ix);
	gout.push_back(gluon);
	}
	for(unsigned int ix=0;ix<3;++ix){
	win.reset(ix);
	vin.push_back(win);
	}
	vector<Complex> diag(3,0.);

	double total(0.);

	AbstractFFVVertexPtr vertex = inter==ShowerInteraction::QCD ? FFGVertex_ : FFPVertex_;

	for(unsigned int inhel1=0;inhel1<3;++inhel1) {
	for(unsigned int outhel1=0;outhel1<2;++outhel1) {
	for(unsigned int outhel2=0;outhel2<2;++outhel2) {
	for(unsigned int outhel3=0;outhel3<2;++outhel3) {
	SpinorBarWaveFunction off1 =
	vertex->evaluate(scale_,3,partons[1]->CC(),fout[outhel1],gout[outhel3]);
	diag[0] = FFWVertex_->evaluate(scale_,aout[outhel2],off1,vin[inhel1]);

	SpinorWaveFunction off2 =
	vertex->evaluate(scale_,3,partons[2]->CC(),aout[outhel2],gout[outhel3]);
	diag[1] = FFWVertex_->evaluate(scale_,off2,fout[outhel1],vin[inhel1]);

	if(inter==ShowerInteraction::QED) {
	VectorWaveFunction off3 =
	WWWVertex_->evaluate(scale_,3,partons[0],vin[inhel1],gout[outhel3]);
	diag[2] = FFWVertex_->evaluate(scale_,aout[outhel2],fout[outhel1],off3);
	}

	// sum of diagrams
	Complex sum = std::accumulate(diag.begin(),diag.end(),Complex(0.));
	// me2
	total += norm(sum);
	}
	}
	}
	}
	// divide out the coupling
	total /= norm(vertex->norm());
	// double g = sqrt(2.)*abs(FFWVertex_->norm());
	// double xg = 2.*momenta[3].t()/momenta[0].mass();
	// double xe,mue2;
	// if(abs(partons[1]->id())==ParticleID::eminus) {
	// xe = 2.*momenta[1].t()/momenta[0].mass();
	// mue2 = sqr(momenta[1].mass()/momenta[0].mass());
	// }
	// else {
	// xe = 2.*momenta[2].t()/momenta[0].mass();
	// mue2 = sqr(momenta[2].mass()/momenta[0].mass());
	// }
	// double cg = -4. * g * g * (-pow(mue2, 3.) / 2. + (xg * xg / 4. + (xe / 2. + 1.) * xg + 5. / 2. * xe - 2.) * mue2 * mue2
	// + (pow(xg, 3.) / 4. + (xe / 4. - 5. / 4.) * xg * xg + (-7. / 2. * xe + 3.) * xg - 3. * xe * xe
	// + 11. / 2. * xe - 7. / 2.) * mue2 + (xg * xg / 2. + (xe - 2.) * xg + xe * xe - 2. * xe + 2.) * (-1. + xg + xe)) * (xe - mue2 - 1.) *
	// pow(xg, -2.) * pow(-1. + xg + xe - mue2, -2.);

	// cerr << "real " << cg/total << "\n";
	// return the total
	return total*UnitRemoval::InvE2;
	}

	double SMWDecayer::calculateRealEmission(double x1, double x2,
	- vector<PPtr> hardProcess,
	+ tcPDVector partons,
	+ vector<Lorentz5Momentum> pin,
	double phi, double muj,
	double muk, int iemit,
	bool subtract) const {
	- // make partons data object for meRatio
	- vector<cPDPtr> partons (3);
	- for(int ix=0; ix<3; ++ix)
	- partons[ix] = hardProcess[ix]->dataPtr();
	- partons.push_back(gluon_);
	// calculate x3
	double x3 = 2.-x1-x2;
	double xT = sqrt(max(0.,sqr(x3)-0.25sqr(sqr(x2)+sqr(x3)-sqr(x1)-4.sqr(muk)+4.*sqr(muj))
	/(sqr(x2)-4.*sqr(muk))));
	// calculate the momenta
	Energy M = mW_;
	Lorentz5Momentum pspect(ZERO,ZERO,-0.5Msqrt(max(sqr(x2)-4.*sqr(muk),0.)),
	0.5Mx2,M*muk);
	Lorentz5Momentum pemit (-0.5MxTcos(phi),-0.5MxTsin(phi),
	0.5Msqrt(max(sqr(x1)-sqr(xT)-4.*sqr(muj),0.)),
	0.5Mx1,M*muj);
	Lorentz5Momentum pgluon(0.5MxTcos(phi), 0.5MxTsin(phi),
	0.5Msqrt(max(sqr(x3)-sqr(xT),0.)),0.5Mx3,ZERO);
	if(abs(pspect.z()+pemit.z()-pgluon.z())/M<1e-6)
	pgluon.setZ(-pgluon.z());
	else if(abs(pspect.z()-pemit.z()+pgluon.z())/M<1e-6)
	pemit .setZ(- pemit.z());
	// boost and rotate momenta
	- LorentzRotation eventFrame( ( hardProcess[1]->momentum() +
	- hardProcess[2]->momentum() ).findBoostToCM() );
	- Lorentz5Momentum spectator = eventFrame*hardProcess[iemit+1]->momentum();
	+ LorentzRotation eventFrame( ( pin[1] +
	+ pin[2] ).findBoostToCM() );
	+ unsigned int ispect = iemit==0 ? 2 : 1;
	+ Lorentz5Momentum spectator = eventFrame*pin[ispect];
	eventFrame.rotateZ( -spectator.phi() );
	eventFrame.rotateY( -spectator.theta() );
	eventFrame.invert();
	vector<Lorentz5Momentum> momenta(3);
	- momenta[0] = hardProcess[0]->momentum();
	- if(iemit==0) {
	- momenta[2] = eventFrame*pspect;
	- momenta[1] = eventFrame*pemit ;
	- }
	- else {
	- momenta[1] = eventFrame*pspect;
	- momenta[2] = eventFrame*pemit ;
	- }
	+ momenta[0] = pin[0];
	+ momenta[ispect ] = eventFrame*pspect;
	+ momenta[iemit+1] = eventFrame*pemit ;
	momenta.push_back(eventFrame*pgluon);
	// calculate the weight
	double realwgt(0.);
	if(1.-x1>1e-5 && 1.-x2>1e-5)
	realwgt = meRatio(partons,momenta,iemit,subtract);
	return realwgt;
	}
	diff --git a/Decay/Perturbative/SMWDecayer.h b/Decay/Perturbative/SMWDecayer.h
	--- a/Decay/Perturbative/SMWDecayer.h
	+++ b/Decay/Perturbative/SMWDecayer.h
	@@ -1,502 +1,520 @@
	// -- C++ --
	//
	// SMWDecayer.h is a part of Herwig - A multi-purpose Monte Carlo event generator
	// Copyright (C) 2002-2017 The Herwig Collaboration
	//
	// Herwig is licenced under version 3 of the GPL, see COPYING for details.
	// Please respect the MCnet academic guidelines, see GUIDELINES for details.
	//
	#ifndef HERWIG_SMWDecayer_H
	#define HERWIG_SMWDecayer_H
	//
	// This is the declaration of the SMWDecayer class.
	//
	-#include "Herwig/Decay/PerturbativeDecayer.h"
	+#include "Herwig/Decay/PerturbativeDecayer2.h"
	#include "ThePEG/Helicity/Vertex/Vector/FFVVertex.h"
	#include "ThePEG/Helicity/Vertex/AbstractVVVVertex.h"
	-#include "Herwig/Decay/DecayPhaseSpaceMode.h"
	+#include "Herwig/Decay/PhaseSpaceMode.h"

	namespace Herwig {
	using namespace ThePEG;
	using namespace ThePEG::Helicity;

	/** \ingroup Decay
	*
	* The <code>SMWDecayer</code> is designed to perform the decay of the
	* W boson to the Standard Model fermions, including the first order
	* electroweak corrections.
	*
	- * @see PerturbativeDecayer
	+ * @see PerturbativeDecayer2
	*
	*/
	-class SMWDecayer: public PerturbativeDecayer {
	+class SMWDecayer: public PerturbativeDecayer2 {

	public:

	/**
	* Default constructor.
	*/
	SMWDecayer();

	public:

	/**
	* Virtual members to be overridden by inheriting classes
	* which implement hard corrections
	*/
	//@{
	/**
	* Has an old fashioned ME correction
	*/
	virtual bool hasMECorrection() {return true;}

	/**
	* Initialize the ME correction
	*/
	virtual void initializeMECorrection(RealEmissionProcessPtr , double & ,
	double & );

	/**
	* Apply the soft matrix element correction
	* @param parent The initial particle in the current branching
	* @param progenitor The progenitor particle of the jet
	* @param fs Whether the emission is initial or final-state
	* @param highestpT The highest pT so far in the shower
	* @param ids ids of the particles produced in the branching
	* @param z The momentum fraction of the branching
	* @param scale the evolution scale of the branching
	* @param pT The transverse momentum of the branching
	* @return If true the emission should be vetoed
	*/
	virtual bool softMatrixElementVeto(PPtr parent,
	PPtr progenitor,
	const bool & fs,
	const Energy & highestpT,
	const vector<tcPDPtr> & ids,
	const double & z,
	const Energy & scale,
	const Energy & pT);

	/**
	* Has a POWHEG style correction
	*/
	virtual POWHEGType hasPOWHEGCorrection() {return FSR;}

	public:

	/**
	* Which of the possible decays is required
	* @param cc Is this mode the charge conjugate
	* @param parent The decaying particle
	* @param children The decay products
	*/
	virtual int modeNumber(bool & cc, tcPDPtr parent,
	const tPDVector & children) const;

	/**
	+ * For a given decay mode and a given particle instance, perform the
	+ * decay and return the decay products. As this is the base class this
	+ * is not implemented.
	+ * @return The vector of particles produced in the decay.
	+ */
	+ virtual ParticleVector decay(const Particle & parent,const tPDVector & children) const;
	+
	+ /**
	* Return the matrix element squared for a given mode and phase-space channel.
	* @param ichan The channel we are calculating the matrix element for.
	* @param part The decaying Particle.
	- * @param decay The particles produced in the decay.
	+ * @param outgoing The particles produced in the decay
	+ * @param momenta The momenta of the particles produced in the decay
	* @param meopt Option for the calculation of the matrix element
	* @return The matrix element squared for the phase-space configuration.
	*/
	- virtual double me2(const int ichan, const Particle & part,
	- const ParticleVector & decay,MEOption meopt) const;
	+ double me2(const int ichan,const Particle & part,
	+ const tPDVector & outgoing,
	+ const vector<Lorentz5Momentum> & momenta,
	+ MEOption meopt) const;
	+
	+ /**
	+ * Construct the SpinInfos for the particles produced in the decay
	+ */
	+ virtual void constructSpinInfo(const Particle & part,
	+ ParticleVector outgoing) const;

	/**
	* Output the setup information for the particle database
	* @param os The stream to output the information to
	* @param header Whether or not to output the information for MySQL
	*/
	virtual void dataBaseOutput(ofstream & os,bool header) const;

	public:

	/** @name Functions used by the persistent I/O system. */
	//@{
	/**
	* Function used to write out object persistently.
	* @param os the persistent output stream written to.
	*/
	void persistentOutput(PersistentOStream & os) const;

	/**
	* Function used to read in object persistently.
	* @param is the persistent input stream read from.
	* @param version the version number of the object when written.
	*/
	void persistentInput(PersistentIStream & is, int version);
	//@}

	/**
	* Standard Init function used to initialize the interfaces.
	*/
	static void Init();

	protected:

	/** @name Clone Methods. */
	//@{
	/**
	* Make a simple clone of this object.
	* @return a pointer to the new object.
	*/
	virtual IBPtr clone() const {return new_ptr(*this);}

	/** Make a clone of this object, possibly modifying the cloned object
	* to make it sane.
	* @return a pointer to the new object.
	*/
	virtual IBPtr fullclone() const {return new_ptr(*this);}
	//@}

	protected:

	/** @name Standard Interfaced functions. */
	//@{
	/**
	* Initialize this object after the setup phase before saving and
	* EventGenerator to disk.
	* @throws InitException if object could not be initialized properly.
	*/
	virtual void doinit();

	/**
	* Initialize this object. Called in the run phase just before
	* a run begins.
	*/
	virtual void doinitrun();
	//@}

	protected:

	/**
	* Set the \f$\rho\f$ parameter
	*/
	void setRho(double);

	/**
	* Set the \f$\tilde{\kappa}\f$ parameters symmetrically
	*/
	void setKtildeSymm();

	/**
	* Set second \f$\tilde{\kappa}\f$, given the first.
	*/
	void setKtilde2();

	/**
	* Translate the variables from \f$x_q,x_{\bar{q}}\f$ to \f$\tilde{\kappa},z\f$
	*/
	//@{
	/**
	* Calculate \f$z\f$.
	*/
	double getZfromX(double, double);

	/**
	* Calculate \f$\tilde{\kappa}\f$.
	*/
	double getKfromX(double, double);
	//@}

	/**
	* Calculate \f$x_{q},x_{\bar{q}}\f$ from \f$\tilde{\kappa},z\f$.
	* @param kt \f$\tilde{\kappa}\f$
	* @param z \f$z\f$
	* @param x \f$x_{q}\f$
	* @param xbar \f$x_{\bar{q}}\f$
	*/
	void getXXbar(double kt, double z, double & x, double & xbar);

	/**
	* Soft weight
	*/
	//@{
	/**
	* Soft quark weight calculated from \f$x_{q},x_{\bar{q}}\f$
	* @param x \f$x_{q}\f$
	* @param xbar \f$x_{\bar{q}}\f$
	*/
	double qWeight(double x, double xbar);

	/**
	* Soft antiquark weight calculated from \f$x_{q},x_{\bar{q}}\f$
	* @param x \f$x_{q}\f$
	* @param xbar \f$x_{\bar{q}}\f$
	*/
	double qbarWeight(double x, double xbar);

	/**
	* Soft quark weight calculated from \f$\tilde{q},z\f$
	* @param qtilde \f$\tilde{q}\f$
	* @param z \f$z\f$
	*/
	double qWeightX(Energy qtilde, double z);

	/**
	* Soft antiquark weight calculated from \f$\tilde{q},z\f$
	* @param qtilde \f$\tilde{q}\f$
	* @param z \f$z\f$
	*/
	double qbarWeightX(Energy qtilde, double z);
	//@}

	/**
	* ????
	*/
	double u(double);

	/**
	* Vector and axial vector parts of the matrix element
	*/
	//@{
	/**
	* Vector part of the matrix element
	*/
	double MEV(double, double);

	/**
	* Axial vector part of the matrix element
	*/
	double MEA(double, double);

	/**
	* The matrix element, given \f$x_1\f$, \f$x_2\f$.
	* @param x1 \f$x_1\f$
	* @param x2 \f$x_2\f$
	*/
	double PS(double x1, double x2);
	//@}

	protected:

	/**
	* Real emission term, for use in generating the hardest emission
	*/
	- double calculateRealEmission(double x1, double x2,
	- vector<PPtr> hardProcess,
	+ double calculateRealEmission(double x1, double x2,
	+ tcPDVector outgoing,
	+ vector<Lorentz5Momentum> momenta,
	double phi, double muj, double muk,
	int iemit, bool subtract) const;

	/**
	* Calculate the ratio between NLO & LO ME
	*/
	- double meRatio(vector<cPDPtr> partons,
	+ double meRatio(tcPDVector partons,
	vector<Lorentz5Momentum> momenta,
	unsigned int iemitter,bool subtract) const;

	/**
	* Calculate matrix element ratio R/B
	*/
	virtual double matrixElementRatio(const Particle & inpart, const ParticleVector & decay2,
	const ParticleVector & decay3, MEOption meopt,
	ShowerInteraction inter);

	/**
	* Calculate the LO ME
	*/
	- double loME(const vector<cPDPtr> & partons,
	+ double loME(const vector<tcPDPtr> & partons,
	const vector<Lorentz5Momentum> & momenta) const;

	/**
	* Calculate the NLO real emission piece of ME
	*/
	- InvEnergy2 realME(const vector<cPDPtr> & partons,
	+ InvEnergy2 realME(const vector<tcPDPtr> & partons,
	const vector<Lorentz5Momentum> & momenta,
	ShowerInteraction inter) const;

	private:

	/**
	* Private and non-existent assignment operator.
	*/
	SMWDecayer & operator=(const SMWDecayer &);

	private:


	/**
	* Pointer to the fermion-antifermion W vertex
	*/
	AbstractFFVVertexPtr FFWVertex_;

	/**
	* Pointer to the fermion-antifermion G vertex
	*/
	AbstractFFVVertexPtr FFGVertex_;

	/**
	* Pointer to the fermion-antifermion G vertex
	*/
	AbstractFFVVertexPtr FFPVertex_;

	/**
	* Pointer to the fermion-antifermion G vertex
	*/
	AbstractVVVVertexPtr WWWVertex_;

	/**
	* maximum weights for the different integrations
	*/
	//@{
	/**
	* Weights for the W to quarks decays.
	*/
	vector<double> quarkWeight_;

	/**
	* Weights for the W to leptons decays.
	*/
	vector<double> leptonWeight_;
	//@}

	/**
	* Spin density matrix for the decay
	*/
	mutable RhoDMatrix rho_;

	/**
	* Polarization vectors for the decay
	*/
	mutable vector<VectorWaveFunction> vectors_;

	/**
	* Spinors for the decay
	*/
	mutable vector<SpinorWaveFunction> wave_;

	/**
	* Barred spinors for the decay
	*/
	mutable vector<SpinorBarWaveFunction> wavebar_;

	private:

	/**
	* CM energy
	*/
	Energy d_Q_;

	/**
	* Quark mass
	*/
	Energy d_m_;

	/**
	* The rho parameter
	*/
	double d_rho_;

	/**
	* The v parameter
	*/
	double d_v_;

	/**
	* The initial kappa-tilde values for radiation from the quark
	*/
	double d_kt1_;

	/**
	* The initial kappa-tilde values for radiation from the antiquark
	*/
	double d_kt2_;

	/**
	* Cut-off parameter
	*/
	static const double EPS_;

	private:

	/**
	* The colour factor
	*/
	double CF_;

	/**
	* The W mass
	*/
	mutable Energy mW_;


	// TODO: delete this
	mutable double mu_;

	/**
	* The reduced mass of particle 1
	*/
	mutable double mu1_;
	/**
	* The reduced mass of particle 1 squared
	*/
	mutable double mu12_;

	/**
	* The reduceed mass of particle 2
	*/
	mutable double mu2_;

	/**
	* The reduceed mass of particle 2 squared
	*/
	mutable double mu22_;


	/**
	* The strong coupling
	*/
	mutable double aS_;

	/**
	* The scale
	*/
	mutable Energy2 scale_;

	/**
	* Stuff for the POWHEG correction
	*/
	//@{
	/**
	* ParticleData object for the gluon
	*/
	tcPDPtr gluon_;

	/**
	* The ParticleData objects for the fermions
	*/
	vector<tcPDPtr> partons_;

	/**
	* The fermion momenta
	*/
	vector<Lorentz5Momentum> quark_;

	/**
	* The momentum of the radiated gauge boson
	*/
	Lorentz5Momentum gauge_;

	/**
	* The W boson
	*/
	PPtr wboson_;

	/**
	* W mass squared
	*/
	Energy2 mw2_;
	//@}

	/**
	* Whether ro return the LO or NLO result
	*/
	bool NLO_;
	};

	}


	#endif /* HERWIG_SMWDecayer_H */

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