15 SUBROUTINE pygvmd(ISET,KF,X,Q2,P2,ALAM,XPGA,VXPGA)
18 IMPLICIT DOUBLE PRECISION(a-
h, o-
z)
22 dimension xpga(-6:6), vxpga(-6:6)
23 DATA pmc/1.3d0/, pmb/4.6d0/, aem/0.007297d0/, aem2pi/0.0011614d0/
33 alam3=alam*(pmc/alam)**(2d0/27d0)
34 alam5=alam*(alam/pmb)**(2d0/23d0)
35 p2eff=
max(p2,1.2d0*alam3**2)
36 IF(kfa.EQ.4) p2eff=
max(p2eff,pmc**2)
37 IF(kfa.EQ.5) p2eff=
max(p2eff,pmb**2)
42 IF(p2eff.LT.pmc**2)
nfp=3
43 IF(p2eff.GT.pmb**2)
nfp=5
45 IF(q2eff.LT.pmc**2) nfq=3
46 IF(q2eff.GT.pmb**2) nfq=5
52 IF(nfq.EQ.3) q2div=q2eff
53 s=
s+(6d0/27d0)*
log(
log(q2div/alam3**2)/
log(p2eff/alam3**2))
55 IF(
nfp.LE.4.AND.nfq.GE.4)
THEN
57 IF(
nfp.EQ.3) p2div=pmc**2
59 IF(nfq.EQ.5) q2div=pmb**2
60 s=
s+(6d0/25d0)*
log(
log(q2div/alam**2)/
log(p2div/alam**2))
64 IF(
nfp.EQ.5) p2div=p2eff
65 s=
s+(6d0/23d0)*
log(
log(q2eff/alam5**2)/
log(p2div/alam5**2))
78 IF(q2.LE.p2.OR.(kfa.EQ.4.AND.q2.LT.pmc**2).OR.
79 & (kfa.EQ.5.AND.q2.LT.pmb**2))
THEN
80 xval =
x * 1.5d0 * (
x**2+x1**2)
84 xval = (1.5d0/(1d0-0.197d0*
s+4.33d0*
s2)*
x**2 +
85 & (1.5d0+2.10d0*
s)/(1d0+3.29d0*
s)*x1**2 +
86 & 5.23d0*
s/(1d0+1.17d0*
s+19.9d0*
s3)*
x*x1) *
87 &
x**(1d0/(1d0+1.5d0*
s)) * (1d0-
x**2)**(2.667d0*
s)
88 xglu = 4d0*
s/(1d0+4.76d0*
s+15.2d0*
s2+29.3d0*
s4) *
89 &
x**(-2.03d0*
s/(1d0+2.44d0*
s)) * (x1*xl)**(1.333d0*
s) *
90 & ((4d0*
x**2+7d0*
x+4d0)*x1/3d0 - 2d0*
x*(1d0+
x)*xl)
91 xsea =
s2/(1d0+4.54d0*
s+8.19d0*
s2+8.05d0*
s3) *
92 &
x**(-1.54d0*
s/(1d0+1.29d0*
s)) * x1**(2.667d0*
s) *
93 & ((8d0-73d0*
x+62d0*
x**2)*x1/9d0 + (3d0-8d0*
x**2/3d0)*
x*xl +
94 & (2d0*
x-1d0)*
x*xl**2)
98 ELSEIF(iset.EQ.1)
THEN
99 IF(q2.LE.p2.OR.(kfa.EQ.4.AND.q2.LT.pmc**2).OR.
100 & (kfa.EQ.5.AND.q2.LT.pmb**2))
THEN
101 xval = 1.294d0 *
x**0.80d0 * x1**0.76d0
102 xglu = 1.273d0 *
x**0.40d0 * x1**1.76d0
103 xsea = 0.100d0 * x1**3.76d0
105 xval = 1.294d0/(1d0+0.252d0*
s+3.079d0*
s2) *
106 &
x**(0.80d0-0.13d0*
s) * x1**(0.76d0+0.667d0*
s) * xl**(2d0*
s)
107 xglu = 7.90d0*
s/(1d0+5.50d0*
s) * exp(-5.16d0*
s) *
108 &
x**(-1.90d0*
s/(1d0+3.60d0*
s)) * x1**1.30d0 *
109 & xl**(0.50d0+3d0*
s) + 1.273d0 * exp(-10d0*
s) *
110 &
x**0.40d0 * x1**(1.76d0+3d0*
s)
111 xsea = (0.1d0-0.397d0*
s2+1.121d0*
s3)/
112 & (1d0+5.61d0*
s2+5.26d0*
s3) *
x**(-7.32d0*
s2/(1d0+10.3d0*
s2)) *
113 & x1**((3.76d0+15d0*
s+12d0*
s2)/(1d0+4d0*
s))
114 xsea0 = 0.100d0 * x1**3.76d0
118 ELSEIF(iset.EQ.2)
THEN
119 IF(q2.LE.p2.OR.(kfa.EQ.4.AND.q2.LT.pmc**2).OR.
120 & (kfa.EQ.5.AND.q2.LT.pmb**2))
THEN
121 xval = 0.8477d0 *
x**0.51d0 * x1**1.37d0
122 xglu = 3.42d0 *
x**0.255d0 * x1**2.37d0
125 xval = 0.8477d0/(1d0+1.37d0*
s+2.18d0*
s2+3.73d0*
s3) *
126 &
x**(0.51d0+0.21d0*
s) * x1**1.37d0 * xl**(2.667d0*
s)
127 xglu = 24d0*
s/(1d0+9.6d0*
s+0.92d0*
s2+14.34d0*
s3) *
128 & exp(-5.94d0*
s) *
x**((-0.013d0-1.80d0*
s)/(1d0+3.14d0*
s)) *
129 & x1**(2.37d0+0.4d0*
s) * xl**(0.32d0+3.6d0*
s) + 3.42d0 *
130 & exp(-12d0*
s) *
x**0.255d0 * x1**(2.37d0+3d0*
s)
131 xsea = 0.842d0*
s/(1d0+21.3d0*
s-33.2d0*
s2+229d0*
s3) *
132 &
x**((0.13d0-2.90d0*
s)/(1d0+5.44d0*
s)) * x1**(3.45d0+0.5d0*
s) *
138 ELSEIF(iset.EQ.3)
THEN
139 IF(q2.LE.p2.OR.(kfa.EQ.4.AND.q2.LT.pmc**2).OR.
140 & (kfa.EQ.5.AND.q2.LT.pmb**2))
THEN
141 xval =
x**0.46d0 * x1**0.64d0 + 0.76d0 *
x
142 xglu = 1.925d0 * x1**2
143 xsea = 0.242d0 * x1**4
145 xval = (1d0+0.186d0*
s)/(1d0-0.209d0*
s+1.495d0*
s2) *
146 &
x**(0.46d0+0.25d0*
s) *
147 & x1**((0.64d0+0.14d0*
s+5d0*
s2)/(1d0+
s)) * xl**(1.9d0*
s) +
148 & (0.76d0+0.4d0*
s) *
x * x1**(2.667d0*
s)
149 xglu = (1.925d0+5.55d0*
s+147d0*
s2)/(1d0-3.59d0*
s+3.32d0*
s2) *
151 &
x**((-5.81d0*
s-5.34d0*
s2)/(1d0+29d0*
s-4.26d0*
s2))
152 & * x1**((2d0-5.9d0*
s)/(1d0+1.7d0*
s)) *
153 & xl**(9.3d0*
s/(1d0+1.7d0*
s))
154 xsea = (0.242d0-0.252d0*
s+1.19d0*
s2)/
155 & (1d0-0.607d0*
s+21.95d0*
s2) *
156 &
x**(-12.1d0*
s2/(1d0+2.62d0*
s+16.7d0*
s2)) * x1**4 * xl**
s
157 xsea0 = 0.242d0 * x1**4
161 ELSEIF(iset.EQ.4)
THEN
162 IF(q2.LE.p2.OR.(kfa.EQ.4.AND.q2.LT.pmc**2).OR.
163 & (kfa.EQ.5.AND.q2.LT.pmb**2))
THEN
164 xval = 1.168d0 *
x**0.50d0 * x1**2.60d0 + 0.965d0 *
x
165 xglu = 1.808d0 * x1**2
166 xsea = 0.209d0 * x1**4
168 xval = (1.168d0+1.771d0*
s+29.35d0*
s2) * exp(-5.776d0*
s) *
169 &
x**((0.5d0+0.208d0*
s)/(1d0-0.794d0*
s+1.516d0*
s2)) *
170 & x1**((2.6d0+7.6d0*
s)/(1d0+5d0*
s)) *
171 & xl**(5.15d0*
s/(1d0+2d0*
s)) +
172 & (0.965d0+22.35d0*
s)/(1d0+18.4d0*
s) *
x * x1**(2.667d0*
s)
173 xglu = (1.808d0+29.9d0*
s)/(1d0+26.4d0*
s) * exp(-5.28d0*
s) *
174 &
x**((-5.35d0*
s-10.11d0*
s2)/(1d0+31.71d0*
s)) *
175 & x1**((2d0-7.3d0*
s+4d0*
s2)/(1d0+2.5d0*
s)) *
176 & xl**(10.9d0*
s/(1d0+2.5d0*
s))
177 xsea = (0.209d0+0.644d0*
s2)/(1d0+0.319d0*
s+17.6d0*
s2) *
178 &
x**((-0.373d0*
s-7.71d0*
s2)/(1d0+0.815d0*
s+11.0d0*
s2)) *
179 & x1**(4d0+
s) * xl**(0.45d0*
s)
180 xsea0 = 0.209d0 * x1**4
185 sll=
log(
log(q2eff/alam**2)/
log(p2eff/alam**2))
187 IF(q2.GT.pmc**2.AND.q2.GT.1.001d0*p2eff)
THEN
188 sch=
max(0d0,
log(
log(pmc**2/alam**2)/
log(p2eff/alam**2)))
190 xchm=xsea*(1d0-(sch/sll)**2)
192 xchm=
max(0d0,xsea-xsea0*x1**(2.667d0*
s))*(1d0-sch/sll)
196 IF(q2.GT.pmb**2.AND.q2.GT.1.001d0*p2eff)
THEN
197 sbt=
max(0d0,
log(
log(pmb**2/alam**2)/
log(p2eff/alam**2)))
199 xbot=xsea*(1d0-(sbt/sll)**2)
201 xbot=
max(0d0,xsea-xsea0*x1**(2.667d0*
s))*(1d0-sbt/sll)
212 xpga(kfa)=xpga(kfa)+xval