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diff --git a/Hadronization/ClusterDecayer.cc b/Hadronization/ClusterDecayer.cc
--- a/Hadronization/ClusterDecayer.cc
+++ b/Hadronization/ClusterDecayer.cc
@@ -1,471 +1,471 @@
// -*- C++ -*-
//
// ClusterDecayer.cc is a part of Herwig++ - A multi-purpose Monte Carlo event generator
// Copyright (C) 2002-2011 The Herwig Collaboration
//
// Herwig++ is licenced under version 2 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 ClusterDecayer class.
//
#include "ClusterDecayer.h"
#include <ThePEG/Interface/ClassDocumentation.h>
#include <ThePEG/Interface/Reference.h>
#include <ThePEG/Interface/Parameter.h>
#include <ThePEG/Interface/Switch.h>
#include <ThePEG/Persistency/PersistentOStream.h>
#include <ThePEG/Persistency/PersistentIStream.h>
#include <ThePEG/PDT/EnumParticles.h>
#include <ThePEG/Repository/EventGenerator.h>
#include "Herwig++/Utilities/Kinematics.h"
#include "CheckId.h"
#include "Cluster.h"
#include <ThePEG/Utilities/DescribeClass.h>
#include <ThePEG/Repository/RandomGenerator.h>
#include <ThePEG/Repository/StandardRandom.h>
using namespace Herwig;
DescribeClass<ClusterDecayer,Interfaced>
describeClusterDecayer("Herwig::ClusterDecayer","");
ClusterDecayer::ClusterDecayer() :
_clDirLight(1),
_clDirBottom(1),
_clDirCharm(1),
_clDirExotic(1),
_clSmrLight(0.0),
_clSmrBottom(0.0),
_clSmrCharm(0.0),
_clSmrExotic(0.0),
_onshell(false),
_masstry(20)
{}
IBPtr ClusterDecayer::clone() const {
return new_ptr(*this);
}
IBPtr ClusterDecayer::fullclone() const {
return new_ptr(*this);
}
void ClusterDecayer::persistentOutput(PersistentOStream & os) const
{
os << _hadronsSelector << _clDirLight << _clDirBottom
<< _clDirCharm << _clDirExotic << _clSmrLight << _clSmrBottom
<< _clSmrCharm << _clSmrExotic << _onshell << _masstry;
}
void ClusterDecayer::persistentInput(PersistentIStream & is, int) {
is >> _hadronsSelector >> _clDirLight >> _clDirBottom
>> _clDirCharm >> _clDirExotic >> _clSmrLight >> _clSmrBottom
>> _clSmrCharm >> _clSmrExotic >> _onshell >> _masstry;
}
void ClusterDecayer::Init() {
static ClassDocumentation<ClusterDecayer> documentation
("This class is responsible for the two-body decays of normal clusters");
static Reference<ClusterDecayer,HadronSelector>
interfaceHadronSelector("HadronSelector",
"A reference to the HadronSelector object",
&Herwig::ClusterDecayer::_hadronsSelector,
false, false, true, false);
//ClDir for light, Bottom, Charm and exotic (e.g Susy) quarks
static Switch<ClusterDecayer,bool> interfaceClDirLight
("ClDirLight",
"Cluster direction for light quarks",
&ClusterDecayer::_clDirLight, true, false, false);
static SwitchOption interfaceClDirLightPreserve
(interfaceClDirLight,
"Preserve",
"Preserve the direction of the quark from the perturbative stage"
" as the direction of the meson produced from it",
true);
static SwitchOption interfaceClDirLightIsotropic
(interfaceClDirLight,
"Isotropic",
"Assign the direction of the meson randomly",
false);
static Switch<ClusterDecayer,bool> interfaceClDirBottom
("ClDirBottom",
"Cluster direction for bottom quarks",
&ClusterDecayer::_clDirBottom, true, false, false);
static SwitchOption interfaceClDirBottomPreserve
(interfaceClDirBottom,
"Preserve",
"Preserve the direction of the quark from the perturbative stage"
" as the direction of the meson produced from it",
true);
static SwitchOption interfaceClDirBottomIsotropic
(interfaceClDirBottom,
"Isotropic",
"Assign the direction of the meson randomly",
false);
static Switch<ClusterDecayer,bool> interfaceClDirCharm
("ClDirCharm",
"Cluster direction for charm quarks",
&ClusterDecayer::_clDirCharm, true, false, false);
static SwitchOption interfaceClDirCharmPreserve
(interfaceClDirCharm,
"Preserve",
"Preserve the direction of the quark from the perturbative stage"
" as the direction of the meson produced from it",
true);
static SwitchOption interfaceClDirCharmIsotropic
(interfaceClDirCharm,
"Isotropic",
"Assign the direction of the meson randomly",
false);
static Switch<ClusterDecayer,bool> interfaceClDirExotic
("ClDirExotic",
"Cluster direction for exotic quarks",
&ClusterDecayer::_clDirExotic, true, false, false);
static SwitchOption interfaceClDirExoticPreserve
(interfaceClDirExotic,
"Preserve",
"Preserve the direction of the quark from the perturbative stage"
" as the direction of the meson produced from it",
true);
static SwitchOption interfaceClDirExoticIsotropic
(interfaceClDirExotic,
"Isotropic",
"Assign the direction of the meson randomly",
false);
// ClSmr for ligth, Bottom, Charm and exotic (e.g. Susy) quarks
static Parameter<ClusterDecayer,double>
interfaceClSmrLight ("ClSmrLight", "cluster direction Gaussian smearing for light quark",
&ClusterDecayer::_clSmrLight, 0, 0.0 , 0.0 , 2.0,false,false,false);
static Parameter<ClusterDecayer,double>
interfaceClSmrBottom ("ClSmrBottom", "cluster direction Gaussian smearing for b quark",
&ClusterDecayer::_clSmrBottom, 0, 0.0 , 0.0 , 2.0,false,false,false);
static Parameter<ClusterDecayer,double>
interfaceClSmrCharm ("ClSmrCharm", "cluster direction Gaussian smearing for c quark",
&ClusterDecayer::_clSmrCharm, 0, 0.0 , 0.0 , 2.0,false,false,false);
static Parameter<ClusterDecayer,double>
interfaceClSmrExotic ("ClSmrExotic", "cluster direction Gaussian smearing for exotic quark",
&ClusterDecayer::_clSmrExotic, 0, 0.0 , 0.0 , 2.0,false,false,false);
static Switch<ClusterDecayer,bool> interfaceOnShell
("OnShell",
"Whether or not the hadrons produced should by on shell or generated using the"
" mass generator.",
&ClusterDecayer::_onshell, false, false, false);
static SwitchOption interfaceOnShellOnShell
(interfaceOnShell,
"Yes",
"Produce the hadrons on shell",
true);
static SwitchOption interfaceOnShellOffShell
(interfaceOnShell,
"No",
"Generate the masses using the mass generator.",
false);
static Parameter<ClusterDecayer,unsigned int> interfaceMassTry
("MassTry",
"The number attempts to generate the masses of the hadrons produced"
" in the cluster decay.",
&ClusterDecayer::_masstry, 20, 1, 50,
false, false, Interface::limited);
}
void ClusterDecayer::decay(const ClusterVector & clusters, tPVector & finalhadrons)
{
// Loop over all clusters, and if they are not too heavy (that is
// intermediate clusters that have undergone to fission) or not
// too light (that is final clusters that have been already decayed
// into single hadron) then decay them into two hadrons.
for (ClusterVector::const_iterator it = clusters.begin();
it != clusters.end(); ++it) {
if ((*it)->isAvailable() && !(*it)->isStatusFinal()
&& (*it)->isReadyToDecay()) {
pair<PPtr,PPtr> prod = decayIntoTwoHadrons(*it);
(*it)->addChild(prod.first);
(*it)->addChild(prod.second);
finalhadrons.push_back(prod.first);
finalhadrons.push_back(prod.second);
}
}
}
pair<PPtr,PPtr> ClusterDecayer::decayIntoTwoHadrons(tClusterPtr ptr) {
using Constants::pi;
using Constants::twopi;
// To decay the cluster into two hadrons one must distinguish between
// constituent quarks (or diquarks) that originate from perturbative
// processes (hard process or parton shower) from those that are generated
// by the non-perturbative gluon splitting or from fission of heavy clusters.
// In the latter case the two body decay is assumed to be *isotropic*.
// In the former case instead, if proper flag are activated, the two body
// decay is assumed to "remember" the direction of the constituents inside
// the cluster, in the cluster frame. The actual smearing of the hadron
// directions around the direction of the constituents, in the cluster
// frame, can be different between non-b hadrons and b-hadrons, but is given
// by the same functional form:
// cosThetaSmearing = 1 + smearFactor * log( rnd() )
// (repeated until cosThetaSmearing > -1)
// where the factor smearFactor is different between b- and non-b hadrons.
//
// We need to require (at least at the moment, maybe in the future we
// could change it) that the cluster has exactly two components.
// If this is not the case, then send a warning because it is not suppose
// to happen, and then return.
if ( ptr->numComponents() != 2 ) {
generator()->logWarning( Exception("ClusterDecayer::decayIntoTwoHadrons "
"***Still cluster with not exactly 2 components*** ",
Exception::warning) );
return pair<PPtr,PPtr>();
}
// Extract the id and particle pointer of the two components of the cluster.
tPPtr ptr1 = ptr->particle(0);
tPPtr ptr2 = ptr->particle(1);
tcPDPtr ptr1data = ptr1->dataPtr();
tcPDPtr ptr2data = ptr2->dataPtr();
bool isHad1FlavSpecial = false;
bool cluDirHad1 = _clDirLight;
double cluSmearHad1 = _clSmrLight;
bool isHad2FlavSpecial = false;
bool cluDirHad2 = _clDirLight;
double cluSmearHad2 = _clSmrLight;
if (CheckId::isExotic(ptr1data)) {
isHad1FlavSpecial = true;
cluDirHad1 = _clDirExotic;
cluSmearHad1 = _clSmrExotic;
}
else if (CheckId::hasBottom(ptr1data)) {
isHad1FlavSpecial = true;
cluDirHad1 = _clDirBottom;
cluSmearHad1 = _clSmrBottom;
}
else if (CheckId::hasCharm(ptr1data)) {
isHad1FlavSpecial = true;
cluDirHad1 = _clDirCharm;
cluSmearHad1 = _clSmrCharm;
}
if (CheckId::isExotic(ptr2data)) {
isHad2FlavSpecial = true;
cluDirHad2 = _clDirExotic;
cluSmearHad2 = _clSmrExotic;
}
else if (CheckId::hasBottom(ptr2data)) {
isHad2FlavSpecial = true;
cluDirHad2 = _clDirBottom;
cluSmearHad2 = _clSmrBottom;
}
else if (CheckId::hasCharm(ptr2data)) {
isHad2FlavSpecial = true;
cluDirHad2 = _clDirCharm;
cluSmearHad2 = _clSmrCharm;
}
bool isOrigin1Perturbative = ptr->isPerturbative(0);
bool isOrigin2Perturbative = ptr->isPerturbative(1);
// We have to decide which, if any, of the two hadrons will have
// the momentum, in the cluster parent frame, smeared around the
// direction of its constituent (for Had1 is the one pointed by
// ptr1, and for Had2 is the one pointed by ptr2).
// This happens only if the flag _ClDirX is 1 and the constituent is
// perturbative (that is not coming from nonperturbative gluon splitting
// or cluster fission). In the case that both the hadrons satisfy this
// two requirements (of course only one must be treated, because the other
// one will have the momentum automatically fixed by the momentum
// conservation) then more priority is given in the case of a b-hadron.
// Finally, in the case that the two hadrons have same priority, then
// we choose randomly, with equal probability, one of the two.
int priorityHad1 = 0;
if ( cluDirHad1 && isOrigin1Perturbative ) {
priorityHad1 = isHad1FlavSpecial ? 2 : 1;
}
int priorityHad2 = 0;
if ( cluDirHad2 && isOrigin2Perturbative ) {
priorityHad2 = isHad2FlavSpecial ? 2 : 1;
}
if ( priorityHad2 && priorityHad1 == priorityHad2 && UseRandom::rndbool() ) {
priorityHad2 = 0;
}
Lorentz5Momentum pClu = ptr->momentum();
bool secondHad = false;
Axis uSmear_v3;
if ( priorityHad1 || priorityHad2 ) {
double cluSmear;
Lorentz5Momentum pQ;
if ( priorityHad1 > priorityHad2 ) {
pQ = ptr1->momentum();
cluSmear = cluSmearHad1;
} else {
pQ = ptr2->momentum();
cluSmear = cluSmearHad2;
secondHad = true;
}
// To find the momenta of the two hadrons in the parent cluster frame
// we proceed as follows. First, we determine the unit vector parallel
// to the direction of the constituent in the cluster frame. Then we
// have to smear such direction using the following prescription:
// --- in theta angle w.r.t. such direction (not the z-axis),
// the drawing of the cosine of such angle is done via:
// 1.0 + cluSmear*log( rnd() )
// (repeated until it gives a value above -1.0)
// --- in phi angle w.r.t. such direction, the drawing is simply flat.
// Then, given the direction in the parent cluster frame of one of the
// two hadrons, it is straighforward to get the momenta of both hadrons
// (always in the same parent cluster frame).
pQ.boost( -pClu.boostVector() ); // boost from Lab to Cluster frame
uSmear_v3 = pQ.vect().unit();
// skip if cluSmear is too small
if ( cluSmear > 0.001 ) {
// generate the smearing angle
double cosSmear;
do cosSmear = 1.0 + cluSmear*log( UseRandom::rnd() );
while ( cosSmear < -1.0 );
double sinSmear = sqrt( 1.0 - sqr(cosSmear) );
// calculate rotation to z axis
LorentzRotation rot;
double sinth(sqrt(1.-sqr(uSmear_v3.z())));
if(abs(uSmear_v3.perp2()/uSmear_v3.z())>1e-10)
rot.setRotate(-acos(uSmear_v3.z()),
Axis(-uSmear_v3.y()/sinth,uSmear_v3.x()/sinth,0.));
// + random azimuthal rotation
rot.rotateZ(UseRandom::rnd()*twopi);
// set direction in rotated frame
Lorentz5Vector<double> ltemp(0.,sinSmear,cosSmear,0.);
// rotate back
rot.invert();
ltemp *= rot;
uSmear_v3 = ltemp.vect();
}
}
else {
// Isotropic decay: flat in cosTheta and phi.
uSmear_v3 = Axis(1.0, 0.0, 0.0); // just to set the rho to 1
uSmear_v3.setTheta( acos( UseRandom::rnd( -1.0 , 1.0 ) ) );
uSmear_v3.setPhi( UseRandom::rnd( -pi , pi ) );
}
pair<tcPDPtr,tcPDPtr> dataPair
= _hadronsSelector->chooseHadronPair(ptr->mass(),
ptr1data,
ptr2data);
if(dataPair.first == tcPDPtr() ||
dataPair.second == tcPDPtr()) return pair<PPtr,PPtr>();
// Create the two hadron particle objects with the specified id.
PPtr ptrHad1,ptrHad2;
// produce the hadrons on mass shell
if(_onshell) {
ptrHad1 = dataPair.first ->produceParticle(dataPair.first ->mass());
ptrHad2 = dataPair.second->produceParticle(dataPair.second->mass());
}
// produce the hadrons with mass given by the mass generator
else {
unsigned int ntry(0);
do {
ptrHad1 = dataPair.first ->produceParticle();
ptrHad2 = dataPair.second->produceParticle();
++ntry;
}
while(ntry<_masstry&&ptrHad1->mass()+ptrHad2->mass()>ptr->mass());
// if fails produce on shell and issue warning (should never happen??)
if( ptrHad1->mass() + ptrHad2->mass() > ptr->mass() ) {
generator()->log() << "Failed to produce off-shell hadrons in "
<< "ClusterDecayer::decayIntoTwoHadrons producing hadrons "
<< "on-shell" << endl;
ptrHad1 = dataPair.first ->produceParticle(dataPair.first ->mass());
ptrHad2 = dataPair.second->produceParticle(dataPair.second->mass());
}
}
if (!ptrHad1 || !ptrHad2) {
ostringstream s;
s << "ClusterDecayer::decayIntoTwoHadrons ***Cannot create the two hadrons***"
<< dataPair.first ->PDGName() << " and "
<< dataPair.second->PDGName();
cerr << s.str() << endl;
generator()->logWarning( Exception(s.str(), Exception::warning) );
} else {
Lorentz5Momentum pHad1, pHad2; // 5-momentum vectors that we have to determine
if ( secondHad ) uSmear_v3 *= -1.0;
if (pClu.m() < ptrHad1->mass()+ptrHad2->mass() ) {
throw Exception() << "Impossible Kinematics in ClusterDecayer::decayIntoTwoHadrons()"
<< Exception::eventerror;
}
Kinematics::twoBodyDecay(pClu,ptrHad1->mass(),ptrHad2->mass(),uSmear_v3,
pHad1,pHad2);
ptrHad1->set5Momentum(pHad1);
ptrHad2->set5Momentum(pHad2);
// Determine the positions of the two children clusters.
LorentzPoint positionHad1 = LorentzPoint();
LorentzPoint positionHad2 = LorentzPoint();
calculatePositions(pClu, ptr->vertex(), pHad1, pHad2, positionHad1, positionHad2);
ptrHad1->setVertex(positionHad1);
ptrHad2->setVertex(positionHad2);
}
return pair<PPtr,PPtr>(ptrHad1,ptrHad2);
}
void ClusterDecayer::
calculatePositions(const Lorentz5Momentum &pClu,
const LorentzPoint &positionClu,
const Lorentz5Momentum &,
const Lorentz5Momentum &,
LorentzPoint &positionHad1,
LorentzPoint &positionHad2 ) const {
// First, determine the relative positions of the children hadrons
// with respect to their parent cluster, in the cluster reference frame,
// assuming gaussian smearing with width inversely proportional to the
// parent cluster mass.
ThePEG::StandardRandom* randomNumberStandardGenerator = new ThePEG::StandardRandom();
Length smearingWidth = hbarc / pClu.m();
LorentzDistance distanceHad[2];
for ( int i = 0; i < 2; i++ ) { // i==0 is the first hadron; i==1 is the second one
- double delta[4]={0.,0.,0.,0.};
+ Length delta[4]={ZERO,ZERO,ZERO,ZERO};
// smearing of the four components of the LorentzDistance, two at the same time to improve speed
for ( int j = 0; j < 3; j += 2 ) {
- randomNumberStandardGenerator->rndGaussTwoNumbers(delta[j], delta[j+1], smearingWidth/femtometer, 0.0);
+ randomNumberStandardGenerator->rndGaussTwoNumbers(delta[j], delta[j+1], smearingWidth, Length(ZERO));
}
// set the distance
delta[0] = abs(delta[0]) +sqrt(sqr(delta[1])+sqr(delta[2])+sqr(delta[3]));
- distanceHad[i] = LorentzVector<double>(delta[1],delta[2],delta[3],delta[0])*femtometer;
+ distanceHad[i] = LorentzDistance(delta[1],delta[2],delta[3],delta[0]);
// Boost such relative positions of the children hadrons,
// with respect to their parent cluster,
// from the cluster reference frame to the Lab frame.
distanceHad[i].boost(pClu.boostVector());
}
// Finally, determine the absolute positions of the children hadrons
// in the Lab frame.
positionHad1 = distanceHad[0] + positionClu;
positionHad2 = distanceHad[1] + positionClu;
}

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