#include "AliPythia.h"
#include "AliPythiaRndm.h"
+#include "../FASTSIM/AliFastGlauber.h"
+#include "../FASTSIM/AliQuenchingWeights.h"
+#include "TVector3.h"
ClassImp(AliPythia)
// Set random number
if (!AliPythiaRndm::GetPythiaRandom())
AliPythiaRndm::SetPythiaRandom(GetRandom());
-
+ fGlauber = 0;
+ fQuenchingWeights = 0;
}
void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfunc)
//
// ATLAS Tuning
//
- SetMSTP(51, 7); // CTEQ5L pdf
+ SetMSTP(51,7); // CTEQ5L pdf
SetMSTP(81,1); // Multiple Interactions ON
SetMSTP(82,4); // Double Gaussian Model
// select Pythia min. bias model
SetMSEL(0);
SetMSUB(95,1); // low pt production
+
+//
+// ATLAS Tuning
+//
- SetMSTP(51, 7); // CTEQ5L pdf
+ SetMSTP(51,7); // CTEQ5L pdf
SetMSTP(81,1); // Multiple Interactions ON
SetMSTP(82,4); // Double Gaussian Model
+void AliPythia::InitQuenching(Float_t cMin, Float_t cMax, Float_t qTransport, Float_t maxLength, Int_t iECMethod)
+{
+// Initializes
+// (1) The quenching model using quenching weights according to C. Salgado and U. Wiedemann
+// (2) The nuclear geometry using the Glauber Model
+//
+
+
+ fGlauber = new AliFastGlauber();
+ fGlauber->Init(2);
+ fGlauber->SetCentralityClass(cMin, cMax);
+
+ fQuenchingWeights = new AliQuenchingWeights();
+ fQuenchingWeights->InitMult();
+ fQuenchingWeights->SetQTransport(qTransport);
+ fQuenchingWeights->SetECMethod(AliQuenchingWeights::kECMethod(iECMethod));
+ fQuenchingWeights->SetLengthMax(Int_t(maxLength));
+ fQuenchingWeights->SampleEnergyLoss();
+
+}
+
+
void AliPythia::Quench()
{
//
// Simple Jet Quenching routine:
// =============================
// The jet formed by all final state partons radiated by the parton created
-// in the hard collisions is quenched by a factor z using:
+// in the hard collisions is quenched by a factor (1-z) using light cone variables in
+// the initial parton reference frame:
// (E + p_z)new = (1-z) (E + p_z)old
//
+//
+//
+//
// The lost momentum is first balanced by one gluon with virtuality > 0.
// Subsequently the gluon splits to yield two gluons with E = p.
//
- Float_t p0[2][5];
- Float_t p1[2][5];
- Float_t p2[2][5];
+//
+//
+ const Int_t kGluons = 1;
+
+ Double_t p0[2][5];
+ Double_t p1[2][5];
+ Double_t p2[2][5];
Int_t klast[2] = {-1, -1};
Int_t kglu[2];
- for (Int_t i = 0; i < 4; i++)
- {
- p0[0][i] = 0.;
- p0[1][i] = 0.;
- p1[0][i] = 0.;
- p1[1][i] = 0.;
- p2[0][i] = 0.;
- p2[1][i] = 0.;
- }
Int_t numpart = fPyjets->N;
-
- for (Int_t i = 0; i < numpart; i++)
- {
- Int_t imo = fPyjets->K[2][i];
- Int_t kst = fPyjets->K[0][i];
- Int_t pdg = fPyjets->K[1][i];
-
-// Quarks and gluons only
- if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
-
-// Particles from hard scattering only
-
-
- Float_t px = fPyjets->P[0][i];
- Float_t py = fPyjets->P[1][i];
- Float_t pz = fPyjets->P[2][i];
- Float_t e = fPyjets->P[3][i];
- Float_t m = fPyjets->P[4][i];
- Float_t pt = TMath::Sqrt(px * px + py * py);
-// Skip comment lines
- if (kst != 1 && kst != 2) continue;
-
- Float_t mt = TMath::Sqrt(px * px + py * py + m * m);
-
- //
- // Some cuts to be in a save kinematic region
- //
- if (imo != 7 && imo != 8) continue;
- Int_t index = imo - 7;
- klast[index] = i;
-
- p0[index][0] += px;
- p0[index][1] += py;
- p0[index][2] += pz;
- p0[index][3] += e;
+ Double_t px = 0., py = 0., pz = 0., e = 0., m = 0., p = 0., pt = 0., theta = 0.;
+ Double_t pxq[2], pyq[2], pzq[2], eq[2], yq[2], mq[2], pq[2], phiq[2], thetaq[2], ptq[2];
+ Bool_t quenched[2];
+ Double_t phi;
+ Double_t zInitial[2], wjtKick[2];
+ Int_t imo, kst, pdg;
//
-// Fix z
+// Primary partons
//
+
+ for (Int_t i = 6; i <= 7; i++) {
+ Int_t j = i - 6;
- Float_t z = 0.2;
- Float_t eppzOld = e + pz;
- Float_t empzOld = e - pz;
-
-
- //
- // Kinematics of the original parton
- //
-
- Float_t eppzNew = (1. - z) * eppzOld;
- Float_t empzNew = empzOld - mt * mt * z / eppzOld;
- Float_t eNew0 = 0.5 * (eppzNew + empzNew);
- Float_t pzNew0 = 0.5 * (eppzNew - empzNew);
- //
- // Skip if pt too small
- //
- if (m * m > eppzNew * empzNew) continue;
- Float_t ptNew = TMath::Sqrt(eppzNew * empzNew - m * m);
- Float_t pxNew0 = ptNew / pt * px;
- Float_t pyNew0 = ptNew / pt * py;
-
- p1[index][0] += pxNew0;
- p1[index][1] += pyNew0;
- p1[index][2] += pzNew0;
- p1[index][3] += eNew0;
- //
- // Update event record
- //
- fPyjets->P[0][i] = pxNew0;
- fPyjets->P[1][i] = pyNew0;
- fPyjets->P[2][i] = pzNew0;
- fPyjets->P[3][i] = eNew0;
+ pxq[j] = fPyjets->P[0][i];
+ pyq[j] = fPyjets->P[1][i];
+ pzq[j] = fPyjets->P[2][i];
+ eq[j] = fPyjets->P[3][i];
+ mq[j] = fPyjets->P[4][i];
+ yq[j] = 0.5 * TMath::Log((e + pz + 1.e-14) / (e - pz + 1.e-14));
+ pq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j]);
+ phiq[j] = TMath::Pi()+TMath::ATan2(-pyq[j], -pxq[j]);
+ ptq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j]);
+ thetaq[j] = TMath::ATan2(ptq[j], pzq[j]);
+ phi = phiq[j];
+
+ // Quench only central jets
+ if (TMath::Abs(yq[j]) > 2.5) {
+ zInitial[j] = 0.;
+ } else {
+ pdg = fPyjets->K[1][i];
+
+ // Get length in nucleus
+ Double_t l;
+ fGlauber->GetLengthsForPythia(1, &phi, &l, -1.);
+ //
+ // Energy loss for given length and parton typr
+ Int_t itype = (pdg == 21) ? 2 : 1;
+ Double_t eloss = fQuenchingWeights->GetELossRandom(itype, l, eq[j]);
+ //
+ // Extra pt
+ wjtKick[j] = TMath::Sqrt(l * fQuenchingWeights->GetQTransport());
+ //
+ // Fractional energy loss
+ zInitial[j] = eloss / eq[j];
+ //
+ // Avoid complete loss
+ //
+ if (zInitial[j] == 1.) zInitial[j] = 0.95;
+ //
+ // Some debug printing
+ printf("Initial parton # %3d, Type %3d Energy %10.3f Phi %10.3f Length %10.3f Loss %10.3f Kick %10.3f\n",
+ j, itype, eq[j], phi, l, eloss, wjtKick[j]);
+ }
+
+ quenched[j] = (zInitial[j] > 0.01);
}
-
- //
- // Gluons
- //
+
+//
+// Radiated partons
+//
+ zInitial[0] = 1. - TMath::Power(1. - zInitial[0], 1./Double_t(kGluons));
+ zInitial[1] = 1. - TMath::Power(1. - zInitial[1], 1./Double_t(kGluons));
+ wjtKick[0] = wjtKick[0] / TMath::Sqrt(Double_t(kGluons));
+ wjtKick[1] = wjtKick[1] / TMath::Sqrt(Double_t(kGluons));
+// this->Pylist(1);
- for (Int_t k = 0; k < 2; k++)
- {
- for (Int_t j = 0; j < 4; j++)
+ for (Int_t iglu = 0; iglu < kGluons; iglu++) {
+ for (Int_t k = 0; k < 4; k++)
{
- p2[k][j] = p0[k][j] - p1[k][j];
+ p0[0][k] = 0.; p0[1][k] = 0.;
+ p1[0][k] = 0.; p1[1][k] = 0.;
+ p2[0][k] = 0.; p2[1][k] = 0.;
}
- p2[k][4] = p2[k][3] * p2[k][3] - p2[k][0] * p2[k][0] - p2[k][1] * p2[k][1] - p2[k][2] * p2[k][2];
-
- if (p2[k][4] > 0.)
+
+ Int_t nq[2] = {0, 0};
+
+ for (Int_t i = 0; i < numpart; i++)
{
+ imo = fPyjets->K[2][i];
+ kst = fPyjets->K[0][i];
+ pdg = fPyjets->K[1][i];
+
+
+
+// Quarks and gluons only
+ if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
+// Particles from hard scattering only
+ if (imo > 8 && imo < 1000) imo = fPyjets->K[2][imo - 1];
+ if (imo != 7 && imo != 8 && imo != 1007 && imo != 1008) continue;
+
+// Skip comment lines
+ if (kst != 1 && kst != 2) continue;
+//
+// Parton kinematic
+ px = fPyjets->P[0][i];
+ py = fPyjets->P[1][i];
+ pz = fPyjets->P[2][i];
+ e = fPyjets->P[3][i];
+ m = fPyjets->P[4][i];
+ pt = TMath::Sqrt(px * px + py * py);
+ p = TMath::Sqrt(px * px + py * py + pz * pz);
+ phi = TMath::Pi() + TMath::ATan2(-py, -px);
+ theta = TMath::ATan2(pt, pz);
+
+//
+// Save 4-momentum sum for balancing
+ Int_t index = imo - 7;
+ if (index >= 1000) index -= 1000;
+
+ p0[index][0] += px;
+ p0[index][1] += py;
+ p0[index][2] += pz;
+ p0[index][3] += e;
+
+// Don't quench radiated gluons
+//
+ if (imo == 1007 || imo == 1008) {
+ p1[index][0] += px;
+ p1[index][1] += py;
+ p1[index][2] += pz;
+ p1[index][3] += e;
+ continue;
+ }
+
+//
+ klast[index] = i;
+//
+// Fractional energy loss
+ Double_t z = zInitial[index];
+ if (!quenched[index]) continue;
//
- // Bring gluon back to mass shell via momentum scaling
- // (momentum will not be conserved, but energy)
//
- // not used anymore
+ // Transform into frame in which initial parton is along z-axis
+ //
+ TVector3 v(px, py, pz);
+ v.RotateZ(-phiq[index]);
+ v.RotateY(-thetaq[index]);
+ Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pl = v.Z();
+ Double_t jt = TMath::Sqrt(pxs * pxs + pys * pys);
+ Double_t mt2 = jt * jt + m * m;
+ Double_t mt = TMath::Sqrt(mt2);
+ Double_t zmin = 0.;
+ Double_t zmax = 1.;
+ //
+ // z**2 mt**2 - pt**2 + pt'**2 > 0
+ // z**2 mt**2 + mt'**2 + m**2 - pt**2
+ // z**2 mt**2 + (1-z)**2 mt**2 + m**2 - pt**2
+ // mt**2(z**2 + 1 + z**2 - 2z) + m**2 - pt**2
+ // mt**2(2z**2 + 1 - 2z) + m**2 - pt**2 > 0
+ // mt**2(2z**2 + 1 - 2z) + 2 m**2 - mt**2 > 0
+ // mt**2(2z**2 - 2z) + 2 m**2 > 0
+ // z mt**2 (1 - z) - m**2 < 0
+ // z**2 - z + 1/4 > 1/4 - m**2/mt**2
+ // (z-1/2)**2 > 1/4 - m**2/mt**2
+ // |z-1/2| > sqrt(1/4 - m**2/mt**2)
+ //
+ // m/mt < 1/2
+ // mt > 2m
+ //
+ if (mt < 2. * m) {
+ printf("No phase space for quenching !: mt (%e) < 2 m (%e) \n", mt, m);
+ p1[index][0] += px;
+ p1[index][1] += py;
+ p1[index][2] += pz;
+ p1[index][3] += e;
+ continue;
+ } else {
+ zmin = 0.5 - TMath::Sqrt(0.25 - m * m / mt2);
+ if (z < zmin) {
+ printf("No phase space for quenching ??: z (%e) < zmin (%e) \n", z, zmin);
+// z = zmin * 1.01;
+
+ p1[index][0] += px;
+ p1[index][1] += py;
+ p1[index][2] += pz;
+ p1[index][3] += e;
+ continue;
+
+ }
+ }
+ //
+ // Kinematic limit on z
+ //
+
+ if (m > 0.) {
+ zmax = 1. - m / TMath::Sqrt(m * m + jt * jt);
+ if (z > zmax) {
+ printf("We have to put z to the kinematic limit %e %e \n", z, zmax);
+ z = 0.9999 * zmax;
+ } // z > zmax
+ if (z < 0.01) {
+//
+// If z is too small, there is no phase space for quenching
+//
+ printf("No phase space for quenching ! %e \n", z);
+
+ p1[index][0] += px;
+ p1[index][1] += py;
+ p1[index][2] += pz;
+ p1[index][3] += e;
+ continue;
+ }
+ } // massive particles
+
+ //
+ // Change light-cone kinematics rel. to initial parton
+ //
+ Double_t eppzOld = e + pl;
+ Double_t empzOld = e - pl;
+
+ Double_t eppzNew = (1. - z) * eppzOld;
+ Double_t empzNew = empzOld - mt2 * z / eppzOld;
+ Double_t eNew0 = 0.5 * (eppzNew + empzNew);
+ Double_t pzNew0 = 0.5 * (eppzNew - empzNew);
+
+ Double_t ptNew;
+ //
+ // if mt very small (or sometimes even < 0 for numerical reasons) set it to 0
+ Double_t mt2New = eppzNew * empzNew;
+ if (mt2New < 1.e-8) mt2New = 0.;
+
+ if (m * m > mt2New) {
+ //
+ // This should not happen
+ //
+ Fatal("Quench()", "This should never happen %e %e %e!", m, eppzNew, empzNew);
+ ptNew = 0;
+ } else {
+ ptNew = TMath::Sqrt(mt2New - m * m);
+ }
+
+
+ //
+ // Calculate new px, py
+ //
+ Double_t pxNew0 = ptNew / jt * pxs;
+ Double_t pyNew0 = ptNew / jt * pys;
/*
- Float_t psq = p2[k][0] * p2[k][0] + p2[k][1] * p2[k][1] + p2[k][2] * p2[k][2];
- Float_t fact = TMath::Sqrt(1. + p2[k][4] / psq);
- p2[k][0] *= fact;
- p2[k][1] *= fact;
- p2[k][2] *= fact;
- p2[k][3] = TMath::Sqrt(psq) * fact;
- p2[k][4] = 0.;
+ Double_t dpx = pxs - pxNew0;
+ Double_t dpy = pys - pyNew0;
+ Double_t dpz = pl - pzNew0;
+ Double_t de = e - eNew0;
+ Double_t dmass2 = de * de - dpx * dpx - dpy * dpy - dpz * dpz;
*/
+ //
+ // Rotate back
+ //
+ TVector3 w(pxNew0, pyNew0, pzNew0);
+ w.RotateY(thetaq[index]);
+ w.RotateZ(phiq[index]);
+ pxNew0 = w.X(); pyNew0 = w.Y(); pzNew0 = w.Z();
+
+
+ p1[index][0] += pxNew0;
+ p1[index][1] += pyNew0;
+ p1[index][2] += pzNew0;
+ p1[index][3] += eNew0;
+ //
+ // Update event record
+ //
+ fPyjets->P[0][i] = pxNew0;
+ fPyjets->P[1][i] = pyNew0;
+ fPyjets->P[2][i] = pzNew0;
+ fPyjets->P[3][i] = eNew0;
+ nq[index]++;
+
}
- }
-
- if (p2[0][4] > 0.) {
- p2[0][4] = TMath::Sqrt(p2[0][4]);
- } else {
- printf("Warning negative mass squared ! \n");
- }
-
- if (p2[1][4] > 0.) {
- p2[1][4] = TMath::Sqrt(p2[1][4]);
- } else {
- printf("Warning negative mass squared ! \n");
- }
-
- //
- // Add the gluons
- //
-
-
- for (Int_t i = 0; i < 2; i++) {
- Int_t ish, jmin, jmax, iGlu, iNew;
- Int_t in = klast[i];
- ish = 0;
-
- if (in == -1) continue;
- if (i == 1 && klast[1] > klast[0]) in += ish;
- jmin = in - 1;
- ish = 1;
-
- if (p2[i][4] > 0) ish = 2;
-
- iGlu = in;
- iNew = in + ish;
- jmax = numpart + ish - 1;
-
- if (fPyjets->K[0][in-1] == 1 || fPyjets->K[0][in-1] == 21 || fPyjets->K[0][in-1] == 11) {
- jmin = in;
- iGlu = in + 1;
- iNew = in;
- }
-
- kglu[i] = iGlu;
+ //
+ // Gluons
+ //
- for (Int_t j = jmax; j > jmin; j--)
+ for (Int_t k = 0; k < 2; k++)
{
- for (Int_t k = 0; k < 5; k++) {
- fPyjets->K[k][j] = fPyjets->K[k][j-ish];
- fPyjets->P[k][j] = fPyjets->P[k][j-ish];
- fPyjets->V[k][j] = fPyjets->V[k][j-ish];
- }
- } // end shifting
- numpart += ish;
- (fPyjets->N) += ish;
-
- if (ish == 1) {
- fPyjets->P[0][iGlu] = p2[i][0];
- fPyjets->P[1][iGlu] = p2[i][1];
- fPyjets->P[2][iGlu] = p2[i][2];
- fPyjets->P[3][iGlu] = p2[i][3];
- fPyjets->P[4][iGlu] = p2[i][4];
-
- fPyjets->K[0][iGlu] = 2;
- fPyjets->K[1][iGlu] = 21;
- fPyjets->K[2][iGlu] = fPyjets->K[2][iNew];
- fPyjets->K[3][iGlu] = -1;
- fPyjets->K[4][iGlu] = -1;
- } else {
//
- // Split gluon in rest frame.
+ // Check if there was phase-space for quenching
//
- Double_t bx = p2[i][0] / p2[i][3];
- Double_t by = p2[i][1] / p2[i][3];
- Double_t bz = p2[i][2] / p2[i][3];
+ if (nq[k] == 0) quenched[k] = kFALSE;
- Float_t pst = p2[i][4] / 2.;
+ if (!quenched[k]) continue;
- Float_t cost = 2. * gRandom->Rndm() - 1.;
- Float_t sint = TMath::Sqrt(1. - cost * cost);
- Float_t phi = 2. * TMath::Pi() * gRandom->Rndm();
+ for (Int_t j = 0; j < 4; j++)
+ {
+ p2[k][j] = p0[k][j] - p1[k][j];
+ }
+ p2[k][4] = p2[k][3] * p2[k][3] - p2[k][0] * p2[k][0] - p2[k][1] * p2[k][1] - p2[k][2] * p2[k][2];
+
+ if (p2[k][4] > 0.) {
+ p2[k][4] = TMath::Sqrt(p2[k][4]);
+ } else {
+ printf("Warning negative mass squared in system %d %f ! \n", k, zInitial[k]);
+ printf("Kinematics %10.3e %10.3e %10.3e %10.3e %10.3e \n", p2[k][0], p2[k][1], p2[k][2], p2[k][3], p2[k][4]);
+ if (p2[k][4] < -0.1) Fatal("Boost", "Negative mass squared !");
+ p2[k][4] = 0.;
+ }
+ //
+ // jt-kick
+ //
+ /*
+ TVector3 v(p2[k][0], p2[k][1], p2[k][2]);
+ v.RotateZ(-phiq[k]);
+ v.RotateY(-thetaq[k]);
+ Double_t px = v.X(); Double_t py = v.Y(); Double_t pz = v.Z();
+ Double_t r = AliPythiaRndm::GetPythiaRandom()->Rndm();
+ Double_t jtKick = wjtKick[k] * TMath::Sqrt(-TMath::Log(r));
+ Double_t phiKick = 2. * TMath::Pi() * AliPythiaRndm::GetPythiaRandom()->Rndm();
+ px += jtKick * TMath::Cos(phiKick);
+ py += jtKick * TMath::Sin(phiKick);
+ TVector3 w(px, py, pz);
+ w.RotateY(thetaq[k]);
+ w.RotateZ(phiq[k]);
+ p2[k][0] = w.X(); p2[k][1] = w.Y(); p2[k][2] = w.Z();
+ p2[k][3] = TMath::Sqrt(p2[k][0] * p2[k][0] + p2[k][1] * p2[k][1] + p2[k][2] * p2[k][2] + p2[k][4] * p2[k][4]);
+ */
+ }
+
+ //
+ // Add the gluons
+ //
+
+ Int_t ish = 0;
+ for (Int_t i = 0; i < 2; i++) {
+ Int_t jmin, jmax, iGlu, iNew;
+ if (!quenched[i]) continue;
+//
+// Last parton from shower i
+ Int_t in = klast[i];
+//
+// Continue if no parton in shower i selected
+ if (in == -1) continue;
+//
+// If this is the second initial parton and it is behind the first move pointer by previous ish
+ if (i == 1 && klast[1] > klast[0]) in += ish;
+//
+// Starting index
- Float_t pz1 = pst * cost;
- Float_t pz2 = -pst * cost;
- Float_t pt1 = pst * sint;
- Float_t pt2 = -pst * sint;
- Float_t px1 = pt1 * TMath::Cos(phi);
- Float_t py1 = pt1 * TMath::Sin(phi);
- Float_t px2 = pt2 * TMath::Cos(phi);
- Float_t py2 = pt2 * TMath::Sin(phi);
+ jmin = in - 1;
+// How many additional gluons will be generated
+ ish = 1;
+ if (p2[i][4] > 0.05) ish = 2;
+//
+// Position of gluons
+ iGlu = in;
+ iNew = in + ish;
+ jmax = numpart + ish - 1;
- fPyjets->P[0][iGlu] = px1;
- fPyjets->P[1][iGlu] = py1;
- fPyjets->P[2][iGlu] = pz1;
- fPyjets->P[3][iGlu] = pst;
- fPyjets->P[4][iGlu] = 0.;
+ if (fPyjets->K[0][in-1] == 1 || fPyjets->K[0][in-1] == 21 || fPyjets->K[0][in-1] == 11) {
+ jmin = in;
+ iGlu = in + 1;
+ iNew = in;
+ }
- fPyjets->K[0][iGlu] = 2;
- fPyjets->K[1][iGlu] = 21;
- fPyjets->K[2][iGlu] = fPyjets->K[2][iNew];
- fPyjets->K[3][iGlu] = -1;
- fPyjets->K[4][iGlu] = -1;
-
- fPyjets->P[0][iGlu+1] = px2;
- fPyjets->P[1][iGlu+1] = py2;
- fPyjets->P[2][iGlu+1] = pz2;
- fPyjets->P[3][iGlu+1] = pst;
- fPyjets->P[4][iGlu+1] = 0.;
+ kglu[i] = iGlu;
+//
+// Shift stack
+//
+ for (Int_t j = jmax; j > jmin; j--)
+ {
+ for (Int_t k = 0; k < 5; k++) {
+ fPyjets->K[k][j] = fPyjets->K[k][j-ish];
+ fPyjets->P[k][j] = fPyjets->P[k][j-ish];
+ fPyjets->V[k][j] = fPyjets->V[k][j-ish];
+ }
+ } // end shifting
- fPyjets->K[0][iGlu+1] = 2;
- fPyjets->K[1][iGlu+1] = 21;
- fPyjets->K[2][iGlu+1] = fPyjets->K[2][iNew];
- fPyjets->K[3][iGlu+1] = -1;
- fPyjets->K[4][iGlu+1] = -1;
- SetMSTU(1,0);
- SetMSTU(2,0);
-
- //
- // Boost back
- //
- Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
-
+ numpart += ish;
+ (fPyjets->N) += ish;
+
+ if (ish == 1) {
+ fPyjets->P[0][iGlu] = p2[i][0];
+ fPyjets->P[1][iGlu] = p2[i][1];
+ fPyjets->P[2][iGlu] = p2[i][2];
+ fPyjets->P[3][iGlu] = p2[i][3];
+ fPyjets->P[4][iGlu] = p2[i][4];
+
+ fPyjets->K[0][iGlu] = 2;
+ fPyjets->K[1][iGlu] = 21;
+ fPyjets->K[2][iGlu] = fPyjets->K[2][iNew] + 1000;
+ fPyjets->K[3][iGlu] = -1;
+ fPyjets->K[4][iGlu] = -1;
+ } else {
+ //
+ // Split gluon in rest frame.
+ //
+ Double_t bx = p2[i][0] / p2[i][3];
+ Double_t by = p2[i][1] / p2[i][3];
+ Double_t bz = p2[i][2] / p2[i][3];
+ Double_t pst = p2[i][4] / 2.;
+ //
+ // Isotropic decay ????
+ Double_t cost = 2. * gRandom->Rndm() - 1.;
+ Double_t sint = TMath::Sqrt(1. - cost * cost);
+ Double_t phi = 2. * TMath::Pi() * gRandom->Rndm();
+
+ Double_t pz1 = pst * cost;
+ Double_t pz2 = -pst * cost;
+ Double_t pt1 = pst * sint;
+ Double_t pt2 = -pst * sint;
+ Double_t px1 = pt1 * TMath::Cos(phi);
+ Double_t py1 = pt1 * TMath::Sin(phi);
+ Double_t px2 = pt2 * TMath::Cos(phi);
+ Double_t py2 = pt2 * TMath::Sin(phi);
+
+ fPyjets->P[0][iGlu] = px1;
+ fPyjets->P[1][iGlu] = py1;
+ fPyjets->P[2][iGlu] = pz1;
+ fPyjets->P[3][iGlu] = pst;
+ fPyjets->P[4][iGlu] = 0.;
+
+ fPyjets->K[0][iGlu] = 2;
+ fPyjets->K[1][iGlu] = 21;
+ fPyjets->K[2][iGlu] = fPyjets->K[2][iNew] + 1000;
+ fPyjets->K[3][iGlu] = -1;
+ fPyjets->K[4][iGlu] = -1;
+
+ fPyjets->P[0][iGlu+1] = px2;
+ fPyjets->P[1][iGlu+1] = py2;
+ fPyjets->P[2][iGlu+1] = pz2;
+ fPyjets->P[3][iGlu+1] = pst;
+ fPyjets->P[4][iGlu+1] = 0.;
+
+ fPyjets->K[0][iGlu+1] = 2;
+ fPyjets->K[1][iGlu+1] = 21;
+ fPyjets->K[2][iGlu+1] = fPyjets->K[2][iNew] + 1000;
+ fPyjets->K[3][iGlu+1] = -1;
+ fPyjets->K[4][iGlu+1] = -1;
+ SetMSTU(1,0);
+ SetMSTU(2,0);
+ //
+ // Boost back
+ //
+ Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
+ }
+ } // end adding gluons
+ //
+ // Check energy conservation
+ Double_t pxs = 0.;
+ Double_t pys = 0.;
+ Double_t pzs = 0.;
+ Double_t es = 14000.;
+
+ for (Int_t i = 0; i < numpart; i++)
+ {
+ kst = fPyjets->K[0][i];
+ if (kst != 1 && kst != 2) continue;
+ pxs += fPyjets->P[0][i];
+ pys += fPyjets->P[1][i];
+ pzs += fPyjets->P[2][i];
+ es -= fPyjets->P[3][i];
+ }
+ if (TMath::Abs(pxs) > 1.e-2 ||
+ TMath::Abs(pys) > 1.e-2 ||
+ TMath::Abs(pzs) > 1.e-1) {
+ printf("%e %e %e %e\n", pxs, pys, pzs, es);
+ this->Pylist(1);
+ Fatal("Quench()", "4-Momentum non-conservation");
}
- } // end adding gluons
-} // end quench
-
+ } // end quenchin loop
+ // Clean-up
+ for (Int_t i = 0; i < numpart; i++)
+ {
+ imo = fPyjets->K[2][i];
+ if (imo > 1000) fPyjets->K[2][i] -= 1000;
+ }
+
+} // end quench