14.9.99Maria Hoerndl, ALPHA++1 My work project Add simple kinematics functions and then more complex routines like Thrust and Jet algorithms to the ALPHA++

14.9.99 Maria Hoerndl, ALPHA++ 1

My work project

Add simple kinematics functions and then morecomplex routines like Thrust and Jet algorithms to the ALPHA++ Analysis Package, and implement the new classes required by these routines Write an analysis program to test the new algorithms

Compare the results of ALPHA and ALPHA++


ALPHA++ Class Diagram


What has changed?

AlphaBanks: new container ObjectV() for all AlObjects new objects created during run time (AlJet, AlThrust) are appended to the ObjectV() vector

STL and CLHEP modules are used

AlObject and QvecBase: the HepLorentzVector _A4V and float _qch contain all important data now new functions: HepLorentzVector A4V() void setA4V(float x, float y, float z, float e); void setA4V(HepLorentzVector vec); void setQCH(float qch);

old functions QP(), QX(), QY(), QZ(), QE(), QM() and QCH()still available

Lock is implemented: int isLocked(); void Lock();


What has changed?

QvecBase: kinematics utility routines are added float QCT(); // cos (polar angle) float QPH(); // phi float QPT(); // transverse momentum float QBETA(); // beta float QGAMMA(); // gamma float QDMSQ(QvecBase j); // mass^2 of 4-mom difference float QDOT3(QvecBase j); //3 dim scalar product float QDECA2(QvecBase j); // cos (decay angle) HepDouble DECAY_ANG(QvecBase j); // cos (decay angle) QvecBase add(QvecBase j); // add four-momenta ….. …..


Class AlThrust

class AlThrust: public QvecBase { public: AlThrust(); // default constructor ALEPHTYPE TYPE() {return ALTHRUST;} Hep3Vector getThrustDirection(); float getThrustValue(); };


Class AlJetclass AlJet: public QvecBase {

public: AlJet(); // default constructor AlJet(const AlJet& oldAj); // copy constructor

ALEPHTYPE TYPE() {return ALJET;} vector<AlObject*>& getObjects(); void addObject(AlObject* a); void setScheme(int s); int getScheme();

private: vector<AlObject*> _objects; // objects of which jet was built int _scheme; // recombination scheme };


Class AlephAlgoclass AlephAlgo { public: AlephAlgo(); AlephAlgo(AlphaBanks* alpha); void setAlphaBanks(AlphaBanks* alpha); AlphaBanks* getAlphaBanks();

//jet algorithms vector<AlJet> DurhamJn(int Scheme, float Ycut, ALEPHTYPE type); vector<AlJet> DurhamJn(int Scheme, float Ycut, vector<AlObject*> Pext); vector<float> DurhamYn(int Scheme, ALEPHTYPE type); vector<float> DurhamYn(int Scheme, vector<AlObject*> Pext);

//thrust algorithms AlThrust AThrust(ALEPHTYPE type); AlThrust AThrust(vector<AlObject*> Pext);

private: AlphaBanks* _alpha;};


Example Analysis Program

which data? class 16 events are used only Eflw objects (type <= 5) conventional criteria for the selection of charged tracks and event selection purpose of program? Calculate the jet-rates for 10 different values of Ycut further analysis of the three-jet events for Ycut = 0.01: store multiplicities, inter-jet-angles, energies and momenta for the three jet events, which are sorted in order of decreasing energies, in an Ntuple using an Hbook wrapper


Example Analysis program

#include "AlephAlgo.h”

void AlephExManager::UserInit(){ // book an ntuple Hbookn(500,"myNtuple",ntags,mytags); }

void AlephExManager::UserEvent(AlphaBanks& bb){ typedef AlphaBanks::AlObjectVec::iterator ObjItr; AlephAlgo a(&bb);

// only EFLOW objects are used, therefore lock all the other objects for(ObjItr it = bb.ObjectV().begin(); it < bb.ObjectV().end(); it++) { if ((*it)->TYPE() != EFLOW)

{ (*it)->Lock(); } }



for(ObjItr it = bb.ObjectV().begin(); it < bb.ObjectV().end(); it++) { if ((*it)->isLocked() == 0) { int type = ((AlEflw*)(*it))->getEfType(); QvecBase* tmp = (QvecBase*)(*it); // selection of good charged tracks if (type <=3) { // calculate Ntpc, ptch, costheta, d0, z0 // lock if bad if ((d0 > 2.) || (z0 > 5.) || (fabs(costheta) > 0.94) || (ptch < 0.2) || (Ntpc < 4)) { (*it)->Lock(); } } // all Eflow objects with eflow type > 5 are locked if (type > 5) { (*it)->Lock(); } } }



// calculate Nchgood and Echgood int Nchgood = 0; int Echgood = 0.; for(ObjItr it = bb.ObjectV().begin(); it < bb.ObjectV().end(); it++) { if ((*it)->isLocked() == 0)

{ int type = ((AlEflw*)(*it))->getEfType(); if (type <=3) { Nchgood ++; Echgood += (*it)->QE(); } } }

//compute thrust axis with all good Eflows AlThrust theThrust = a.AThrust(EFLOW); Hep3Vector theThrAxis = theThrust.getThrustDirection(); float costhr = theThrAxis.cosTheta();



if ((Nchgood >=5) && (Echgood >=15.) && (fabs(costhr) < 0.82)) { // store all not locked objects in the vector<AlObject*> selobj; vector<AlObject*> selobj; for(ObjItr it = bb.ObjectV().begin(); it < bb.ObjectV().end(); it++) { if (((*it)->isLocked() == 0) && ((*it)->TYPE() == EFLOW)) { selobj.push_back(*it); } }

// compute the different jet-rates as a function of Ycut; for(int i=0; i<10; i++) { vector<AlJet> Jn = a.DurhamJn(1, Ycut[i], selobj); jetr = Jn.size(); // fill jetr into Ntuple // take three jet events for Ycut = 0.01 if (( i == 5) && ( jetr == 3 )) { for(int j=0; j<3; j++)

{ jetmomentum[j] = Jn[j].A4V(); // calculate the multiplicity



for(ObjItr it1 = Jn[j].getObjects().begin(); it1 <Jn[j].getObjects().end(); it1 ++)

{ int type = ((AlEflw*)(*it1))->getEfType(); if (type <=3) { multiplicity[j]++; } } } // sort multiplicity and jetmomentum in order of decreasing energy // calculate the interjetangles interjetangle[0]=jetmomentum[0].angle( Hep3Vector(jetmomentum[1])); interjetangle[1] = ……. interjetangle[2] = …... // fill the rest of the ntuple array } // of if 3jet } // of for over ycuts // fill the ntuple array into the ntuple } // of if good event fout << endl << " =====> in UserEvent " << Nev << endl;}

data output agrees with that from ALPHA !


Jet energies


Jet multiplicities


Jet Rates


Gluon jets


Quark jets


Analysis of the Quark jets


Analysis of the Quark jets


Summary

most important algorithms have been implemented

“usability” has been shown via realistic QCD analysis

agreement with Fortran

to be done: detailed performance study

Documents

14.9.99Maria Hoerndl, ALPHA++1 My work project Add simple kinematics functions and then more complex routines like Thrust and Jet algorithms to the ALPHA++