Gabriele Cosmo
203 lines
6.6 KiB
C++
203 lines
6.6 KiB
C++
//
|
|
// ********************************************************************
|
|
// * DISCLAIMER *
|
|
// * *
|
|
// * The following disclaimer summarizes all the specific disclaimers *
|
|
// * of contributors to this software. The specific disclaimers,which *
|
|
// * govern, are listed with their locations in: *
|
|
// * http://cern.ch/geant4/license *
|
|
// * *
|
|
// * Neither the authors of this software system, nor their employing *
|
|
// * institutes,nor the agencies providing financial support for this *
|
|
// * work make any representation or warranty, express or implied, *
|
|
// * regarding this software system or assume any liability for its *
|
|
// * use. *
|
|
// * *
|
|
// * This code implementation is the intellectual property of the *
|
|
// * GEANT4 collaboration. *
|
|
// * By copying, distributing or modifying the Program (or any work *
|
|
// * based on the Program) you indicate your acceptance of this *
|
|
// * statement, and all its terms. *
|
|
// ********************************************************************
|
|
//
|
|
//
|
|
#ifndef G4ProjectileFragmentCrossSection_h
|
|
#define G4ProjectileFragmentCrossSection_h 1
|
|
|
|
#include <cmath>
|
|
#include <iostream>
|
|
|
|
// Implements Physical Review C61, 034607 (2000)
|
|
// Rewrite starting from EPAX Version 2
|
|
|
|
class G4ProjectileFragmentCrossSection
|
|
{
|
|
public:
|
|
G4ProjectileFragmentCrossSection()
|
|
{
|
|
p_S[1] = -2.38; // scale factor for xsect in barn
|
|
p_S[2] = 0.27;
|
|
|
|
p_P[1] = -2.5840E+00; // slope of mass yield curve
|
|
p_P[2] = -7.5700E-03;
|
|
|
|
p_Delta[1] = -1.0870E+00; // centroid rel. to beta-stability
|
|
p_Delta[2] = +3.0470E-02;
|
|
p_Delta[3] = +2.1353E-04;
|
|
p_Delta[4] = +7.1350E+01;
|
|
|
|
p_R[1] = +0.885E+00; // width parameter R
|
|
p_R[2] = -9.8160E-03;
|
|
|
|
p_Un[1] = 1.65; // slope par. n-rich ride of Z distr.
|
|
|
|
p_Up[1] = 1.7880; // slope par. p-rich ride of Z distr.
|
|
p_Up[2] = +4.7210E-03;
|
|
p_Up[3] = -1.3030E-05;
|
|
|
|
p_mn[1] = 0.400; // memory effect n-rich projectiles
|
|
p_mn[2] = 0.600;
|
|
|
|
p_mp[1] = -10.25; // memory effect p-rich projectiles
|
|
p_mp[2] = +10.1;
|
|
|
|
corr_d[1] = -25.0; // correction close to proj.: centroid dzp
|
|
corr_d[2] = 0.800;
|
|
corr_r[1] = +20.0; // correction close to proj.: width R
|
|
corr_r[2] = 0.820;
|
|
corr_y[1] = 200.0; // correction close to proj.: Yield_a
|
|
corr_y[2] = 0.90;
|
|
}
|
|
|
|
inline G4double doit(G4double Ap, G4double Zp, G4double At, G4double Zt, G4double A, G4double Z)
|
|
{
|
|
// calculate mass yield
|
|
G4double Ap13 = pow(Ap, 1./3.);
|
|
G4double At13 = pow(At, 1./3.);
|
|
G4double S = p_S[2] * (At13 + Ap13 + p_S[1]);
|
|
// cout << "debug0 "<<S<<" "<<At13<<" "<<Ap13<<" "<<p_S[1]<<" "<<p_S[2]<<endl;
|
|
G4double p = exp(p_P[2]*Ap + p_P[1]);
|
|
G4double yield_a = p * S * exp(-p * (Ap - A));
|
|
cout << "debug1 "<<yield_a<<endl;
|
|
// modification close to projectile
|
|
G4double f_mod_y=1.0;
|
|
if (A/Ap > corr_y[2])
|
|
{
|
|
f_mod_y=corr_y[1]*pow(A/Ap-corr_y[2], 2) + 1.0;
|
|
}
|
|
yield_a= yield_a * f_mod_y;
|
|
cout << "debug1 "<<yield_a<<endl;
|
|
|
|
// calculate maximum of charge dispersion zprob
|
|
G4double zbeta = A/(1.98+0.0155*pow(A, (2./3.)));
|
|
G4double zbeta_p = Ap/(1.98+0.0155*pow(Ap, (2./3.)));
|
|
G4double delta;
|
|
if(A > p_Delta[4])
|
|
{
|
|
delta = p_Delta[1] + p_Delta[2]*A;
|
|
}
|
|
else
|
|
{
|
|
delta = p_Delta[3]*A*A;
|
|
}
|
|
|
|
// modification close to projectile
|
|
G4double f_mod=1.0;
|
|
if(A/Ap > corr_d[2])
|
|
{
|
|
f_mod = corr_d[1]*pow(A/Ap-corr_d[2], 2) + 1.0;
|
|
}
|
|
delta = delta*f_mod;
|
|
G4double zprob = zbeta+delta;
|
|
|
|
// correction for proton- and neutron-rich projectiles
|
|
G4double dq;
|
|
if((Zp-zbeta_p)>0)
|
|
{
|
|
dq = exp(p_mp[1] + G4double(A)/G4double(Ap)*p_mp[2]);
|
|
cout << "dq "<<A<<" "<<Ap<<" "<<p_mp[1]
|
|
<<" "<<p_mp[2]<<" "<<dq<<" "<<p_mp[1] + A/Ap*p_mp[2]<<endl;
|
|
}
|
|
else
|
|
{
|
|
dq = p_mn[1]*pow(A/Ap, 2.0) + p_mn[2]*pow(A/Ap, 4.0);
|
|
}
|
|
zprob = zprob + dq * (Zp-zbeta_p);
|
|
|
|
// small corr. since Xe-129 and Pb-208 are not on Z_beta line
|
|
zprob = zprob + 0.0020*A;
|
|
cout <<"zprob "<<A<<" "<<dq<<" "<<Zp<<" "<<zbeta_p
|
|
<<" "<<zbeta<<" "<<delta<<endl;
|
|
|
|
// calculate width parameter R
|
|
G4double r = exp(p_R[1] + p_R[2]*A);
|
|
|
|
// modification close to projectile
|
|
f_mod=1.0;
|
|
if (A/Ap > corr_r[2])
|
|
{
|
|
f_mod = corr_r[1]*Ap*pow(A/Ap-corr_r[2], 4.0)+1.0;
|
|
}
|
|
r = r*f_mod;
|
|
|
|
// change width according to dev. from beta-stability
|
|
if ((Zp-zbeta_p) < 0.0)
|
|
{
|
|
r=r*(1.0-0.0833*abs(Zp-zbeta_p));
|
|
}
|
|
|
|
// calculate slope parameters u_n, u_p
|
|
G4double u_n = p_Un[1];
|
|
G4double u_p = p_Up[1] + p_Up[2]*A + p_Up[3]*A*A;
|
|
|
|
// calculate charge dispersion
|
|
G4double expo, fract;
|
|
if((zprob-Z) > 0)
|
|
{
|
|
// neutron-rich
|
|
expo = -r*pow(abs(zprob-Z), u_n);
|
|
fract = exp(expo)*sqrt(r/3.14159);
|
|
}
|
|
else
|
|
{
|
|
// proton-rich
|
|
expo = -r*pow(abs(zprob-Z), u_p);
|
|
fract = exp(expo)*sqrt(r/3.14159);
|
|
cout << "1 "<<expo<<" "<<r<<" "<<zprob<<" "<<Z<<" "<<u_p<<endl;
|
|
// go to exponential slope
|
|
G4double dfdz = 1.2 + 0.647*pow(A/2.,0.3);
|
|
G4double z_exp = zprob + dfdz * log(10.) / (2.*r);
|
|
if( Z>z_exp )
|
|
{
|
|
expo = -r*pow(abs(zprob-z_exp), u_p);
|
|
fract = exp(expo)*sqrt(r/3.14159)
|
|
/ pow(pow(10, dfdz), Z-z_exp);
|
|
}
|
|
}
|
|
|
|
cout << "debug "<<fract<<" "<<yield_a<<endl;
|
|
G4double epaxv2=fract*yield_a;
|
|
return epaxv2;
|
|
}
|
|
|
|
void testMe()
|
|
{
|
|
G4ProjectileFragmentCrossSection i;
|
|
cout << i.doit(58, 28, 9, 4, 49, 28) << endl;
|
|
// Sigma = 9.800163E-13 b
|
|
}
|
|
private:
|
|
G4double p_S[3];
|
|
G4double p_P[3];
|
|
G4double p_Delta[5];
|
|
G4double p_R[3];
|
|
G4double p_Un[2];
|
|
G4double p_Up[4];
|
|
G4double p_mn[3];
|
|
G4double p_mp[3];
|
|
G4double corr_d[3];
|
|
G4double corr_r[3];
|
|
G4double corr_y[3];
|
|
};
|
|
#endif
|