Page MenuHomeHEPForge
Files F19244487

VVKinematics.cc
No OneTemporary
Actions

Size
18 KB
Referenced Files
None
Subscribers
None

VVKinematics.cc
View Options

// -*- C++ -*-
//
// VVKinematics.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 VVKinematics class.
//
#include "VVKinematics.h"
using namespace Herwig;
bornVVKinematics::bornVVKinematics() {}
bornVVKinematics::bornVVKinematics(vector<Lorentz5Momentum> Momenta,
double x1, double x2) {
// Leading order momentum fractions and associated etabar's:
x1b_ = x1;
eta1b_ = sqrt(1.-x1b_);
x2b_ = x2;
eta2b_ = sqrt(1.-x2b_);
// The Born momenta according to the notation of the FMNR papers,
// in the diboson centre of mass frame:
p1b_ = Momenta[0];
p2b_ = Momenta[1];
k1b_ = Momenta[2];
k2b_ = Momenta[3];
// The diboson invariant mass / shat, that and uhat:
sb_ = (p1b_+p2b_).m2();
tb_ = (p1b_-k1b_).m2();
ub_ = (p1b_-k2b_).m2();
// Masses of the final state bosons:
k12b_ = k1b_.m2();
k22b_ = k2b_.m2();
// Boost the momenta so they are in the diboson centre of mass frame
// with the quark along the +z direction:
Lorentz5Momentum ktot(k1b_+k2b_);
Boost CMSBoostb(-ktot.boostVector());
p1b_.boost(CMSBoostb);
p2b_.boost(CMSBoostb);
k1b_.boost(CMSBoostb);
k2b_.boost(CMSBoostb);
if(p1b_.z()<0.*GeV) {
p1b_.rotateY(Constants::pi);
p2b_.rotateY(Constants::pi);
k1b_.rotateY(Constants::pi);
k2b_.rotateY(Constants::pi);
}
// The diboson rapidity:
Yb_ = 0.5*log(x1b_/x2b_);
// N.B. this gives the diboson rapidity in the lab (lastY()) IF p1 is in the +z
// direction otherwise Yb_ is minus the diboson rapidity in the lab (-lastY()).
// Polar and azimuthal angles of the dibosons in their rest frame:
theta1b_ = acos(k1b_.z()/k1b_.vect().mag());
}
void bornVVKinematics::sanityCheck() const {
// The masses and angles can be used to reconstruct the momenta in
// the diboson centre of mass frame as follows (as a sanity check):
Energy4 lambda = sb_*sb_+k12b_*k12b_+k22b_*k22b_
-2.*sb_*k12b_- 2.*sb_*k22b_ - 2.*k12b_*k22b_;
Energy p = sqrt(lambda)/2./sqrt(sb_);
Energy pt = p*sin(theta1b_);
Energy pl = p*cos(theta1b_);
Lorentz5Momentum p1b(0.*GeV,0.*GeV, p1b_.t(),p1b_.t(),0.*GeV);
Lorentz5Momentum p2b(0.*GeV,0.*GeV,-p2b_.t(),p2b_.t(),0.*GeV);
double eventAzimuth = atan2(k1b_.x(),k1b_.y());
Lorentz5Momentum k1b( pt*sin(eventAzimuth), pt*cos(eventAzimuth), pl,
sqrt(p*p+k12b_),sqrt(k12b_));
Lorentz5Momentum k2b(-pt*sin(eventAzimuth),-pt*cos(eventAzimuth),-pl,
sqrt(p*p+k22b_),sqrt(k22b_));
// Checks showed these momenta agreed with p1b_,p2b_,k1b_,k2b_ to within
// 0.01 eV. These therefore correspond to theta's of Frixione et al.
Lorentz5Momentum p1bdiff(p1b_-p1b);
Lorentz5Momentum p2bdiff(p2b_-p2b);
Lorentz5Momentum k1bdiff(k1b_-k1b);
Lorentz5Momentum k2bdiff(k2b_-k2b);
if(p1bdiff.x()/GeV>1.e-7||p1bdiff.y()/GeV>1.e-7||p1bdiff.z()/GeV>1.e-7||
p1bdiff.t()/GeV>1.e-7||p1bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nbornVVKinematics:\n";
cout << "p1b_ = " << p1b_/GeV << endl;
cout << "p1b = " << p1b/GeV << endl;
cout << "p1bdiff = " << p1bdiff/GeV << endl;
}
if(p2bdiff.x()/GeV>1.e-7||p2bdiff.y()/GeV>1.e-7||p2bdiff.z()/GeV>1.e-7||
p2bdiff.t()/GeV>1.e-7||p2bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nbornVVKinematics:\n";
cout << "p2b_ = " << p2b_/GeV << endl;
cout << "p2b = " << p2b/GeV << endl;
cout << "p2bdiff = " << p2bdiff/GeV << endl;
}
if(k1bdiff.x()/GeV>1.e-7||k1bdiff.y()/GeV>1.e-7||k1bdiff.z()/GeV>1.e-7||
k1bdiff.t()/GeV>1.e-7||k1bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nbornVVKinematics:\n";
cout << "k1b_ = " << k1b_/GeV << endl;
cout << "k1b = " << k1b/GeV << endl;
cout << "k1bdiff = " << k1bdiff/GeV << endl;
}
if(k2bdiff.x()/GeV>1.e-7||k2bdiff.y()/GeV>1.e-7||k2bdiff.z()/GeV>1.e-7||
k2bdiff.t()/GeV>1.e-7||k2bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nbornVVKinematics:\n";
cout << "k2b_ = " << k2b_/GeV << endl;
cout << "k2b = " << k2b/GeV << endl;
cout << "k2bdiff = " << k2bdiff/GeV << endl;
}
return;
}
realVVKinematics::realVVKinematics() {}
realVVKinematics::realVVKinematics(bornVVKinematics bornVariables,
double xt, double y, double theta2) {
// Store the bornVVKinematics object
bornVariables_ = bornVariables;
// Store the `raw' radiative variables
xt_ = xt;
y_ = y ;
theta2r_ = theta2;
// First we get the lower limit on the x integration, xbar:
if(y_== 1.) xbar_ = bornVariables.x1b();
else if(y_==-1.) xbar_ = bornVariables.x2b();
else {
double x1b(bornVariables.x1b()), x2b(bornVariables.x2b());
double x12b(x1b*x1b) , x22b(x2b*x2b);
double omy(1.-y_);
double opy(1.+y_);
double xbar1=2.*opy*x12b/
(sqrt(sqr(1.+x12b)*sqr(omy)+16.*y_*x12b)+omy*(1.-x1b)*(1.+x1b));
double xbar2=2.*omy*x22b/
(sqrt(sqr(1.+x22b)*sqr(opy)-16.*y_*x22b)+opy*(1.-x2b)*(1.+x2b));
xbar_ = max(xbar1,xbar2);
}
// Then we calculate x from \tilde{x}:
xr_ = xt_==1. ? 1. : xbar_+(1.-xbar_)*xt_;
if(xr_== 1.) x1r_ = bornVariables.x1b();
else if(y_ ==-1.) x1r_ = bornVariables.x1b();
else if(y_ == 1.) x1r_ = bornVariables.x1b()/xr_;
else x1r_ = (bornVariables.x1b()/sqrt(xr_))
* sqrt((2.-(1.-xr_)*(1.-y_))/(2.-(1.-xr_)*(1.+y_)));
if(xr_== 1.) x2r_ = bornVariables.x2b();
else if(y_ ==-1.) x2r_ = bornVariables.x2b()/xr_;
else if(y_ == 1.) x2r_ = bornVariables.x2b();
else x2r_ = (bornVariables.x2b()/sqrt(xr_))
* sqrt((2.-(1.-xr_)*(1.+y_))/(2.-(1.-xr_)*(1.-y_)));
// The diboson invariant mass is preserved as are the individual
// diboson masses, as are theta1 and theta2:
s2r_ = bornVariables.sb();
k12r_ = bornVariables.k12b();
k22r_ = bornVariables.k22b();
theta1r_ = bornVariables.theta1b();
if(xt_==1.) {
// Now determine the variables of Frixione et al. for this x and y.
// Eq.2.6 of WZ paper NPB 383(1992) 3-44):
sr_ = s2r_;
tkr_ = 0.*GeV2;
ukr_ = 0.*GeV2;
// Eq.2.12 of WZ paper NPB 383(1992) 3-44:
cpsir_ = -1.;
cpsiprr_= 999.;
}
else if(y_== 1.) {
// Now determine the variables of Frixione et al. for this x and y.
// Eq.2.6 of WZ paper NPB 383(1992) 3-44):
sr_ = s2r_/xr_;
tkr_ = 0.*GeV2;
ukr_ = -sr_*(1.-xr_);
// Eq.2.12 of WZ paper NPB 383(1992) 3-44:
cpsir_ = -1.;
cpsiprr_= 1.;
}
else if(y_==-1.) {
// Now determine the variables of Frixione et al. for this x and y.
// Eq.2.6 of WZ paper NPB 383(1992) 3-44):
sr_ = s2r_/xr_;
tkr_ = -sr_*(1.-xr_);
ukr_ = 0.*GeV2;
// Eq.2.12 of WZ paper NPB 383(1992) 3-44:
cpsir_ = -1.;
cpsiprr_= -1.;
}
else {
// Now determine the variables of Frixione et al. for this x and y.
// Eq.2.6 of WZ paper NPB 383(1992) 3-44):
sr_ = s2r_/xr_;
tkr_ = -0.5*sr_*(1.-xr_)*(1.-y_);
ukr_ = -0.5*sr_*(1.-xr_)*(1.+y_);
// Eq.2.12 of WZ paper NPB 383(1992) 3-44:
double omxy((1.-xr_)*y_);
double opx(1.+xr_);
cpsir_ = -8.*xr_/(opx+omxy)/(opx-omxy)+1.;
cpsiprr_ = (1.+y_-xr_*(1.-y_))/(1.+y_+xr_*(1.-y_));
// If an unphysical value of cos(psi) or cos(psi^prime) results,
// and if the kinematics are also extreme (x-> 1) try setting
// cpsir_ or cpsiprr_ to +/-1. accordingly.
double tiny(1.e-10);
double roundingError(0.);
if(!(fabs(cpsir_)<=1.&&fabs(cpsiprr_)<=1.)) {
if(cpsir_ > 1.&&cpsir_ < 1.+tiny)
{ roundingError=cpsir_-1.; cpsir_ = 1.; }
if(cpsir_ < -1.&&cpsir_ > -1.-tiny)
{ roundingError=cpsir_+1.; cpsir_ =-1.; }
if(cpsiprr_ > 1.&&cpsiprr_ < 1.+tiny)
{ roundingError=cpsiprr_-1.; cpsiprr_=1.; }
if(cpsiprr_ < -1.&&cpsiprr_ > -1.-tiny)
{ roundingError=cpsiprr_+1.; cpsiprr_=-1.; }
if(fabs(roundingError)>=tiny)
throw Exception()
<< "realVVKinematics::realVVKinematics:\n"
<< "cosine of psi or psi^prime not in range -1,1.\n"
<< "1.-xr_ = " << 1.-xr_ << "\n"
<< "y_ = " << y_ << "\n"
<< "cpsir_ = " << cpsir_ << "\n"
<< "1.+cpsir_ = " << 1.+cpsir_ << "\n"
<< "1.-cpsir_ = " << 1.-cpsir_ << "\n"
<< "cpsiprr_ = " << cpsiprr_ << "\n"
<< "1.+cpsiprr_ = " << 1.+cpsiprr_ << "\n"
<< "1.-cpsiprr_ = " << 1.-cpsiprr_ << "\n"
<< "Consider increasing the local variable tiny" << "\n"
<< Exception::warning;
}
}
// Remainder of Eq.2.12 of WZ paper NPB 383(1992) 3-44:
Energy rs2(sqrt(s2r_ ));
Energy m1(sqrt(k12r_));
Energy m2(sqrt(k22r_));
betaxr_ = sqrt(rs2+m1+m2) * sqrt(rs2-m1+m2)
* sqrt(rs2-m1-m2) * sqrt(rs2+m1-m2) / s2r_;
v1r_ = s2r_*betaxr_/(s2r_-(m2-m1)*(m2+m1));
v2r_ = s2r_*betaxr_/(s2r_+(m2-m1)*(m2+m1));
// Eq.2.13 of WZ paper NPB 383(1992) 3-44:
if(xt_==1.) {
q1r_ = k12r_ - 0.5*(sr_ )*betaxr_/v1r_*(1.-v1r_*cos(theta1r_));
q2r_ = k22r_ - 0.5*(sr_ )*betaxr_/v2r_*(1.-v2r_*cos(theta1r_));
}
else if(y_== 1.) {
q1r_ = k12r_ - 0.5*(sr_ )*betaxr_/v1r_*(1.-v1r_*cos(theta1r_));
q2r_ = k22r_ - 0.5*(sr_*xr_ )*betaxr_/v2r_*(1.-v2r_*cos(theta1r_));
}
else if(y_==-1.) {
q1r_ = k12r_ - 0.5*(sr_*xr_ )*betaxr_/v1r_*(1.-v1r_*cos(theta1r_));
q2r_ = k22r_ - 0.5*(sr_ )*betaxr_/v2r_*(1.-v2r_*cos(theta1r_));
}
else {
q1r_ = k12r_ - 0.5*(sr_+tkr_)*betaxr_/v1r_*(1.-v1r_*cos(theta1r_));
q2r_ = k22r_ - 0.5*(sr_+ukr_)*betaxr_/v2r_*(1.+v2r_*cos(theta2r_)
*sin(theta1r_)*sqrt(1.-cpsir_)*sqrt(1.+cpsir_)
+v2r_*cos(theta1r_)*cpsir_);
}
// Eq.2.7 of WZ paper NPB 383(1992) 3-44 (s2 was already defined above):
q1hatr_ = k12r_ + k22r_ - sr_ - tkr_ - q1r_;
q2hatr_ = k12r_ + k22r_ - sr_ - ukr_ - q2r_;
w1r_ = k12r_ - q1r_ + q2r_ - tkr_;
w2r_ = k22r_ + q1r_ - q2r_ - ukr_;
// Reconstruct the momenta. k1b_, k2b_ should not have changed modulo
// +/- conventions for things like sin(psi) and sin(psi^prime) (cf
// Eq.2.12 of WZ paper).
Energy p10r( (sr_ +tkr_)/2./sqrt(s2r_));
Energy p20r( (sr_ +ukr_)/2./sqrt(s2r_));
Energy k0r (-(ukr_+tkr_)/2./sqrt(s2r_));
double spsir = sqrt(1.-cpsir_ )*sqrt(1.+cpsir_ );
double spsiprr = sqrt(1.-cpsiprr_)*sqrt(1.+cpsiprr_);
p1r_ = Lorentz5Momentum(0.*GeV,0.*GeV,p10r,p10r,0.*GeV);
p2r_ = Lorentz5Momentum(0.*GeV, p20r*spsir ,p20r*cpsir_ ,p20r,0.*GeV);
kr_ = Lorentz5Momentum(0.*GeV, k0r *spsiprr,k0r *cpsiprr_,k0r ,0.*GeV);
k1r_ = Lorentz5Momentum(sqrt(s2r_)*v1r_*sin(theta2r_)*sin(theta1r_),
sqrt(s2r_)*v1r_*cos(theta2r_)*sin(theta1r_),
sqrt(s2r_)*v1r_*cos(theta1r_),
sqrt(s2r_),sqrt(k12r_));
k2r_ = Lorentz5Momentum(sqrt(s2r_)*-v2r_*sin(theta2r_)*sin(theta1r_),
sqrt(s2r_)*-v2r_*cos(theta2r_)*sin(theta1r_),
sqrt(s2r_)*-v2r_*cos(theta1r_),
sqrt(s2r_),sqrt(k22r_));
k1r_ *= betaxr_/2./v1r_;
k2r_ *= betaxr_/2./v2r_;
k1r_.setTau(sqrt(k12r_));
k2r_.setTau(sqrt(k22r_));
return;
}
void realVVKinematics::sanityCheck() const {
// Sanity check: reconstruct the momenta and check agreement with
// k1b_, k2b_. These should not have changed modulo +/- conventions
// for things like sin(psi) and sin(psi^prime) (cf Eq.2.12 of WZ paper).
Energy p10r( (sr_ +tkr_)/2./sqrt(s2r_));
Energy p20r( (sr_ +ukr_)/2./sqrt(s2r_));
Energy k0r (-(ukr_+tkr_)/2./sqrt(s2r_));
double spsir = sqrt(1-cpsir_ )*sqrt(1.+cpsir_ );
double spsiprr = sqrt(1-cpsiprr_)*sqrt(1.+cpsiprr_);
Lorentz5Momentum p1r(0.*GeV,0.*GeV,p10r,p10r,0.*GeV);
Lorentz5Momentum p2r(0.*GeV, p20r*spsir ,p20r*cpsir_ ,p20r,0.*GeV);
Lorentz5Momentum kr (0.*GeV, k0r *spsiprr,k0r *cpsiprr_,k0r ,0.*GeV);
Lorentz5Momentum k1r(sqrt(s2r_)*v1r_*sin(theta2r_)*sin(theta1r_),
sqrt(s2r_)*v1r_*cos(theta2r_)*sin(theta1r_),
sqrt(s2r_)*v1r_*cos(theta1r_),
sqrt(s2r_),sqrt(k12r_));
Lorentz5Momentum k2r(sqrt(s2r_)*-v2r_*sin(theta2r_)*sin(theta1r_),
sqrt(s2r_)*-v2r_*cos(theta2r_)*sin(theta1r_),
sqrt(s2r_)*-v2r_*cos(theta1r_),
sqrt(s2r_),sqrt(k22r_));
k1r *= betaxr_/2./v1r_;
k2r *= betaxr_/2./v2r_;
k1r.setTau(sqrt(k12r_));
k2r.setTau(sqrt(k22r_));
// Check that everything is on shell (nearly):
if((p1r.m()-p1r.mass())/MeV>5.||(p2r.m()-p2r.mass())/MeV>5.||
(kr.m() -kr.mass() )/MeV>5.||
(k1r.m()-k1r.mass())/MeV>5.||(k2r.m()-k2r.mass())/MeV>5.) {
cout << "\nrealVVKinematics off-shell particle(s) reconstructed:\n";
cout << "p1r = " << p1r /GeV << " "
<< "mass = " << p1r.mass()/GeV << " m = " << p1r.m()/GeV << endl;
cout << "p2r = " << p2r /GeV << " "
<< "mass = " << p2r.mass()/GeV << " m = " << p2r.m()/GeV << endl;
cout << "kr = " << kr /GeV << " "
<< "mass = " << kr.mass() /GeV << " m = " << kr.m() /GeV << endl;
cout << "k1r = " << k1r /GeV << " "
<< "mass = " << k1r.mass()/GeV << " m = " << k1r.m()/GeV << endl;
cout << "k2r = " << k2r /GeV << " "
<< "mass = " << k2r.mass()/GeV << " m = " << k2r.m()/GeV << endl;
}
// Check that the total momentum is conserved:
Lorentz5Momentum total;
total = p1r+p2r-kr-k1r-k2r;
if(total.x()/MeV>0.1||total.y()/MeV>0.1||total.z()/MeV>0.1||
total.t()/MeV>0.1)
cout << "\nrealVVKinematics momentum imbalance = " << total/GeV << endl;
// OK rescale all spatial components so the invariant length
// equals exactly the invariant length element of the 5Vector.
p1r.rescaleRho();
p2r.rescaleRho();
kr.rescaleRho();
k1r.rescaleRho();
k2r.rescaleRho();
// Check that the total momentum is still conserved after the rescaling:
total = p1r+p2r-kr-k1r-k2r;
if(total.x()/MeV>0.1||total.y()/MeV>0.1||total.z()/MeV>0.1||
total.t()/MeV>0.1)
cout << "\nrealVVKinematics momentum imbalance = " << total/GeV << endl;
// Check that the final state momenta k1 and k2 are the same as
// they are in the 2->2 process up to an azimuthal rotation; note
// that the azimuthal angle of k1 and k2 in their rest frame is
// defined by the radiative variable theta2 which is in turn defined
// w.r.t the transverse momentum of the emitted parton, while in
// the born process the azimuthal angle of k1 / k2 is basically
// meaningless (random).
Lorentz5Momentum k1diff(bornVariables_.k1b()-k1r);
Lorentz5Momentum k2diff(bornVariables_.k2b()-k2r);
Energy k1pTdiff(bornVariables_.k1b().perp()-k1r.perp());
Energy k2pTdiff(bornVariables_.k2b().perp()-k2r.perp());
if(k1pTdiff/GeV>1.e-7||k1diff.z()/GeV>1.e-7||
k1diff.t()/GeV>1.e-7||k1diff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics:\n";
cout << "k1b = " << bornVariables_.k1b()/GeV << endl;
cout << "k1r = " << k1r /GeV << endl;
cout << "k1diff = " << k1diff/GeV << endl;
cout << "pTdiff = " << k1pTdiff/GeV << endl;
}
if(k2pTdiff/GeV>1.e-7||k2diff.z()/GeV>1.e-7||
k2diff.t()/GeV>1.e-7||k2diff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics:\n";
cout << "k2b = " << bornVariables_.k2b()/GeV << endl;
cout << "k2r = " << k2r /GeV << endl;
cout << "k2diff = " << k2diff/GeV << endl;
cout << "pTdiff = " << k2pTdiff/GeV << endl;
}
// Check also that for y_=+/-1 you also get Born-like initial state momenta
if(xt_!=1.&&y_== 1.) {
Lorentz5Momentum p1bdiff = (p1r-kr-bornVariables_.p1b());
if(p1bdiff.x()/GeV>1.e-7||p1bdiff.y()/GeV>1.e-7||p1bdiff.z()/GeV>1.e-7||
p1bdiff.t()/GeV>1.e-7||p1bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for y_= 1.\n";
cout << "p1r-kr = " << (p1r-kr) /GeV << endl;
cout << "p1b = " << bornVariables_.p1b() /GeV << endl;
cout << "p1r-kr-p1b = " << (p1r-kr-bornVariables_.p1b())/GeV << endl;
}
Lorentz5Momentum p2bdiff = (p2r-bornVariables_.p2b());
if(p2bdiff.x()/GeV>1.e-7||p2bdiff.y()/GeV>1.e-7||p2bdiff.z()/GeV>1.e-7||
p2bdiff.t()/GeV>1.e-7||p2bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for y_=-1.\n";
cout << "p2r = " << p2r /GeV << endl;
cout << "p2b = " << bornVariables_.p2b() /GeV << endl;
cout << "p2r-p2b = " << (p2r-bornVariables_.p2b())/GeV << endl;
}
}
if(xt_!=1.&&y_==-1.) {
Lorentz5Momentum p2bdiff = (p2r-kr-bornVariables_.p2b());
if(p2bdiff.x()/GeV>1.e-7||p2bdiff.y()/GeV>1.e-7||p2bdiff.z()/GeV>1.e-7||
p2bdiff.t()/GeV>1.e-7||p2bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for y_=-1.\n";
cout << "p2r-kr = " << (p2r-kr) /GeV << endl;
cout << "p2b = " << bornVariables_.p2b() /GeV << endl;
cout << "p2r-kr-p2b = " << (p2r-kr-bornVariables_.p2b())/GeV << endl;
}
Lorentz5Momentum p1bdiff = (p1r-bornVariables_.p1b());
if(p1bdiff.x()/GeV>1.e-7||p1bdiff.y()/GeV>1.e-7||p1bdiff.z()/GeV>1.e-7||
p1bdiff.t()/GeV>1.e-7||p1bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for y_=-1.\n";
cout << "p1r = " << p1r /GeV << endl;
cout << "p1b = " << bornVariables_.p1b() /GeV << endl;
cout << "p1r-p1b = " << (p1r-bornVariables_.p1b())/GeV << endl;
}
}
// And that for xt_=1 you also get the Born initial state momenta
if(xt_== 1.) {
Lorentz5Momentum p1bdiff = (p1r-bornVariables_.p1b());
if(p1bdiff.x()/GeV>1.e-7||p1bdiff.y()/GeV>1.e-7||p1bdiff.z()/GeV>1.e-7||
p1bdiff.t()/GeV>1.e-7||p1bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for xt_= 1.\n";
cout << "p1r = " << p1r /GeV << endl;
cout << "p1b = " << bornVariables_.p1b() /GeV << endl;
cout << "p1r-p1b = " << (p1r-bornVariables_.p1b())/GeV << endl;
}
Lorentz5Momentum p2bdiff = (p2r-bornVariables_.p2b());
if(p2bdiff.x()/GeV>1.e-7||p2bdiff.y()/GeV>1.e-7||p2bdiff.z()/GeV>1.e-7||
p2bdiff.t()/GeV>1.e-7||p2bdiff.tau()/GeV>1.e-7) {
cout << "\n\n\nrealVVKinematics: error for xt_= 1.\n";
cout << "p2r = " << p2r /GeV << endl;
cout << "p2b = " << bornVariables_.p2b() /GeV << endl;
cout << "p2r-p2b = " << (p2r-bornVariables_.p2b())/GeV << endl;
}
}
return;
}

File Metadata

Mime Type
text/x-c
Expires
Tue, Sep 30, 4:42 AM (1 d, 12 h)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
6532501
Default Alt Text
VVKinematics.cc (18 KB)

Event Timeline

HEPForge.org · .