1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
// -*- C++ -*-
//
// GRVBase.cc is a part of ThePEG - Toolkit for HEP Event Generation
// Copyright (C) 1999-2011 Leif Lonnblad
//
// ThePEG 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 GRVBase class.
//
#include "GRVBase.h"
#include "ThePEG/PDT/ParticleData.h"
#include "ThePEG/PDT/EnumParticles.h"
#include "ThePEG/Persistency/PersistentOStream.h"
#include "ThePEG/Persistency/PersistentIStream.h"
#include "ThePEG/Utilities/Rebinder.h"
#include "ThePEG/Utilities/Maths.h"
#include "ThePEG/Utilities/DescribeClass.h"
#include "ThePEG/Interface/ClassDocumentation.h"
using namespace ThePEG;
GRVBase::GRVBase()
: theLx(-1.0), thex(-1.0), theEps(-1.0), theRootx(-1.0),
Q2(-GeV2), theLam2(-GeV2), theMu2(-GeV2),
theS(-1.0), theS2(-1.0), theS3(-1.0), theRootS(-1.0),
uvSave(-1.0), dvSave(-1.0), delSave(-1.0), udbSave(-1.0), sbSave(-1.0),
cbSave(-1.0), bbSave(-1.0), glSave(-1.0) {}
GRVBase::~GRVBase() {}
bool GRVBase::canHandleParticle(tcPDPtr particle) const {
return ( abs(particle->id()) == abs(long(ParticleID::pplus)) ||
abs(particle->id()) == abs(long(ParticleID::n0)) );
}
cPDVector GRVBase::partons(tcPDPtr p) const {
cPDVector ret;
if ( canHandleParticle(p) ) {
ret.push_back(getParticleData(ParticleID::g));
for ( int i = 1; i <= 5; ++i ) {
ret.push_back(getParticleData(i));
ret.push_back(getParticleData(-i));
}
}
return ret;
}
double GRVBase::xfl(tcPDPtr particle, tcPDPtr parton, Energy2 partonScale,
double l, Energy2) const {
setup(l, partonScale);
if ( S() < 0.0 ) return 0.0;
using namespace ParticleID;
bool anti = particle->id() < 0;
bool neutron = abs(particle->id()) == n0;
switch ( parton->id() ) {
case b:
case bbar:
return max(fbb(), 0.0);
case c:
case cbar:
return max(fcb(), 0.0);
case s:
case sbar:
return max(fsb(), 0.0);
case u:
return max(neutron? (fudb() + fdel() + (anti? 0.0: fdv())):
(fudb() - fdel() + (anti? 0.0: fuv())), 0.0);
case ubar:
return max(neutron? (fudb() + fdel() + (anti? fdv(): 0.0)):
(fudb() - fdel() + (anti? fuv(): 0.0)), 0.0);
case d:
return max(neutron? (fudb() - fdel() + (anti? 0.0: fuv())):
(fudb() + fdel() + (anti? 0.0: fdv())), 0.0);
case dbar:
return max(neutron? (fudb() - fdel() + (anti? fuv(): 0.0)):
(fudb() + fdel() + (anti? fdv(): 0.0)), 0.0);
case g:
return max(fgl(), 0.0);
}
return 0.0;
}
double GRVBase::xfvl(tcPDPtr particle, tcPDPtr parton, Energy2 partonScale,
double l, Energy2) const {
setup(l, partonScale);
if ( S() < 0.0 ) return 0.0;
using namespace ParticleID;
bool anti = particle->id() < 0;
bool neutron = abs(particle->id()) == n0;
switch ( parton->id() ) {
case u:
return max(neutron? (anti? 0.0: fdv()): (anti? 0.0: fuv()), 0.0);
case ubar:
return max(neutron? (anti? fdv(): 0.0): (anti? fuv(): 0.0), 0.0);
case d:
return max(neutron? (anti? 0.0: fuv()): (anti? 0.0: fdv()), 0.0);
case dbar:
return max(neutron? (anti? fuv(): 0.0): (anti? fdv(): 0.0), 0.0);
}
return 0.0;
}
double GRVBase::valens(double N, double ak, double bk,
double a, double b, double c, double d) const {
return N*pow(x(), ak)*pow(eps(), d)*
(1.0 + a*pow(x(), bk) + x()*(b + c*sqrt(x())));
}
double GRVBase::
lightsea(double al, double be, double ak, double bk,
double a, double b, double c, double d, double e, double es) const {
return (pow(x(), ak)*(a + x()*(b + x()*c))*pow(lx(), bk) +
pow(S(), al)*exp(sqrt(es*pow(S(), be)*lx()) - e))*pow(eps(), d);
}
double GRVBase::
heavysea(double sth, double al, double be, double ak, double ag,
double b, double d, double e, double es) const {
return S() <= sth? 0.0:
pow(S() - sth, al)*(1.0 + rootx()*ag + x()*b)*pow(eps(), d)*
exp(sqrt(es*pow(S(), be)*lx()) - e)/pow(lx(),ak);
}
void GRVBase::
setup(double l, Energy2 scale, Energy2 mu2, Energy2 lam2) const {
if ( l == lx() && scale == Q2 && mu2 == theMu2 && lam2 == theLam2 ) return;
if ( l != lx() || scale != Q2 || mu2 != theMu2 || lam2 != theLam2 ) {
uvSave = dvSave = delSave = udbSave = -1.0;
sbSave = cbSave = bbSave = glSave = -1.0;
}
if ( l != lx() ) {
theLx = l;
thex = exp(-l);
if ( l < 0.0 ) throw PDFRange(name(), "momentum fraction", thex, 1.0);
theEps = Math::exp1m(-l);
theRootx = sqrt(x());
}
if ( scale != Q2 || mu2 != theMu2 || lam2 != theLam2 ) {
Q2 = scale;
theMu2 = mu2;
theLam2 = lam2;
if ( scale <= mu2 ) {
switch ( rangeException ) {
case rangeThrow:
throw PDFRange(name(), "scale (in GeV^2)", scale/GeV2, mu2/GeV2);
case rangeZero:
theS = -1.0;
return;
case rangeFreeze:
theS = 0.0;
}
} else
theS = log(log(scale/lam2)/log(mu2/lam2));
theS2 = sqr(S());
theS3 = S()*S2();
theRootS = sqrt(S());
}
}
DescribeAbstractNoPIOClass<GRVBase,PDFBase>
describeGRVBase("ThePEG::GRVBase", "GRVBase.so");
void GRVBase::Init() {
static ClassDocumentation<GRVBase> documentation
("This is the base class used by different GRV PDF parameterizations.");
}
|
