SUBROUTINE PYPDPO(X,Q2,XPPR) C...Double precision and integer declarations. IMPLICIT DOUBLE PRECISION(A-H, O-Z) IMPLICIT INTEGER(I-N) INTEGER PYK,PYCHGE,PYCOMP C...Commonblocks. COMMON/PYDAT1/MSTU(200),PARU(200),MSTJ(200),PARJ(200) COMMON/PYDAT2/KCHG(500,4),PMAS(500,4),PARF(2000),VCKM(4,4) COMMON/PYPARS/MSTP(200),PARP(200),MSTI(200),PARI(200) COMMON/PYINT1/MINT(400),VINT(400) SAVE /PYDAT1/,/PYDAT2/,/PYPARS/,/PYINT1/ DIMENSION XPPR(-6:6),XQ(9),TX(6),TT(6),TS(6),NEHLQ(8,2), &CEHLQ(6,6,2,8,2),CDO(3,6,5,2) C...The following data lines are coefficients needed in the C...Eichten, Hinchliffe, Lane, Quigg proton structure function C...parametrizations, see below. C...Powers of 1-x in different cases. DATA NEHLQ/3,4,7,5,7,7,7,7,3,4,7,6,7,7,7,7/ C...Expansion coefficients for up valence quark distribution. DATA (((CEHLQ(IX,IT,NX,1,1),IX=1,6),IT=1,6),NX=1,2)/ 1 7.677D-01,-2.087D-01,-3.303D-01,-2.517D-02,-1.570D-02,-1.000D-04, 2-5.326D-01,-2.661D-01, 3.201D-01, 1.192D-01, 2.434D-02, 7.620D-03, 3 2.162D-01, 1.881D-01,-8.375D-02,-6.515D-02,-1.743D-02,-5.040D-03, 4-9.211D-02,-9.952D-02, 1.373D-02, 2.506D-02, 8.770D-03, 2.550D-03, 5 3.670D-02, 4.409D-02, 9.600D-04,-7.960D-03,-3.420D-03,-1.050D-03, 6-1.549D-02,-2.026D-02,-3.060D-03, 2.220D-03, 1.240D-03, 4.100D-04, 1 2.395D-01, 2.905D-01, 9.778D-02, 2.149D-02, 3.440D-03, 5.000D-04, 2 1.751D-02,-6.090D-03,-2.687D-02,-1.916D-02,-7.970D-03,-2.750D-03, 3-5.760D-03,-5.040D-03, 1.080D-03, 2.490D-03, 1.530D-03, 7.500D-04, 4 1.740D-03, 1.960D-03, 3.000D-04,-3.400D-04,-2.900D-04,-1.800D-04, 5-5.300D-04,-6.400D-04,-1.700D-04, 4.000D-05, 6.000D-05, 4.000D-05, 6 1.700D-04, 2.200D-04, 8.000D-05, 1.000D-05,-1.000D-05,-1.000D-05/ DATA (((CEHLQ(IX,IT,NX,1,2),IX=1,6),IT=1,6),NX=1,2)/ 1 7.237D-01,-2.189D-01,-2.995D-01,-1.909D-02,-1.477D-02, 2.500D-04, 2-5.314D-01,-2.425D-01, 3.283D-01, 1.119D-01, 2.223D-02, 7.070D-03, 3 2.289D-01, 1.890D-01,-9.859D-02,-6.900D-02,-1.747D-02,-5.080D-03, 4-1.041D-01,-1.084D-01, 2.108D-02, 2.975D-02, 9.830D-03, 2.830D-03, 5 4.394D-02, 5.116D-02,-1.410D-03,-1.055D-02,-4.230D-03,-1.270D-03, 6-1.991D-02,-2.539D-02,-2.780D-03, 3.430D-03, 1.720D-03, 5.500D-04, 1 2.410D-01, 2.884D-01, 9.369D-02, 1.900D-02, 2.530D-03, 2.400D-04, 2 1.765D-02,-9.220D-03,-3.037D-02,-2.085D-02,-8.440D-03,-2.810D-03, 3-6.450D-03,-5.260D-03, 1.720D-03, 3.110D-03, 1.830D-03, 8.700D-04, 4 2.120D-03, 2.320D-03, 2.600D-04,-4.900D-04,-3.900D-04,-2.300D-04, 5-6.900D-04,-8.200D-04,-2.000D-04, 7.000D-05, 9.000D-05, 6.000D-05, 6 2.400D-04, 3.100D-04, 1.100D-04, 0.000D+00,-2.000D-05,-2.000D-05/ C...Expansion coefficients for down valence quark distribution. DATA (((CEHLQ(IX,IT,NX,2,1),IX=1,6),IT=1,6),NX=1,2)/ 1 3.813D-01,-8.090D-02,-1.634D-01,-2.185D-02,-8.430D-03,-6.200D-04, 2-2.948D-01,-1.435D-01, 1.665D-01, 6.638D-02, 1.473D-02, 4.080D-03, 3 1.252D-01, 1.042D-01,-4.722D-02,-3.683D-02,-1.038D-02,-2.860D-03, 4-5.478D-02,-5.678D-02, 8.900D-03, 1.484D-02, 5.340D-03, 1.520D-03, 5 2.220D-02, 2.567D-02,-3.000D-05,-4.970D-03,-2.160D-03,-6.500D-04, 6-9.530D-03,-1.204D-02,-1.510D-03, 1.510D-03, 8.300D-04, 2.700D-04, 1 1.261D-01, 1.354D-01, 3.958D-02, 8.240D-03, 1.660D-03, 4.500D-04, 2 3.890D-03,-1.159D-02,-1.625D-02,-9.610D-03,-3.710D-03,-1.260D-03, 3-1.910D-03,-5.600D-04, 1.590D-03, 1.590D-03, 8.400D-04, 3.900D-04, 4 6.400D-04, 4.900D-04,-1.500D-04,-2.900D-04,-1.800D-04,-1.000D-04, 5-2.000D-04,-1.900D-04, 0.000D+00, 6.000D-05, 4.000D-05, 3.000D-05, 6 7.000D-05, 8.000D-05, 2.000D-05,-1.000D-05,-1.000D-05,-1.000D-05/ DATA (((CEHLQ(IX,IT,NX,2,2),IX=1,6),IT=1,6),NX=1,2)/ 1 3.578D-01,-8.622D-02,-1.480D-01,-1.840D-02,-7.820D-03,-4.500D-04, 2-2.925D-01,-1.304D-01, 1.696D-01, 6.243D-02, 1.353D-02, 3.750D-03, 3 1.318D-01, 1.041D-01,-5.486D-02,-3.872D-02,-1.038D-02,-2.850D-03, 4-6.162D-02,-6.143D-02, 1.303D-02, 1.740D-02, 5.940D-03, 1.670D-03, 5 2.643D-02, 2.957D-02,-1.490D-03,-6.450D-03,-2.630D-03,-7.700D-04, 6-1.218D-02,-1.497D-02,-1.260D-03, 2.240D-03, 1.120D-03, 3.500D-04, 1 1.263D-01, 1.334D-01, 3.732D-02, 7.070D-03, 1.260D-03, 3.400D-04, 2 3.660D-03,-1.357D-02,-1.795D-02,-1.031D-02,-3.880D-03,-1.280D-03, 3-2.100D-03,-3.600D-04, 2.050D-03, 1.920D-03, 9.800D-04, 4.400D-04, 4 7.700D-04, 5.400D-04,-2.400D-04,-3.900D-04,-2.400D-04,-1.300D-04, 5-2.600D-04,-2.300D-04, 2.000D-05, 9.000D-05, 6.000D-05, 4.000D-05, 6 9.000D-05, 1.000D-04, 2.000D-05,-2.000D-05,-2.000D-05,-1.000D-05/ C...Expansion coefficients for up and down sea quark distributions. DATA (((CEHLQ(IX,IT,NX,3,1),IX=1,6),IT=1,6),NX=1,2)/ 1 6.870D-02,-6.861D-02, 2.973D-02,-5.400D-03, 3.780D-03,-9.700D-04, 2-1.802D-02, 1.400D-04, 6.490D-03,-8.540D-03, 1.220D-03,-1.750D-03, 3-4.650D-03, 1.480D-03,-5.930D-03, 6.000D-04,-1.030D-03,-8.000D-05, 4 6.440D-03, 2.570D-03, 2.830D-03, 1.150D-03, 7.100D-04, 3.300D-04, 5-3.930D-03,-2.540D-03,-1.160D-03,-7.700D-04,-3.600D-04,-1.900D-04, 6 2.340D-03, 1.930D-03, 5.300D-04, 3.700D-04, 1.600D-04, 9.000D-05, 1 1.014D+00,-1.106D+00, 3.374D-01,-7.444D-02, 8.850D-03,-8.700D-04, 2 9.233D-01,-1.285D+00, 4.475D-01,-9.786D-02, 1.419D-02,-1.120D-03, 3 4.888D-02,-1.271D-01, 8.606D-02,-2.608D-02, 4.780D-03,-6.000D-04, 4-2.691D-02, 4.887D-02,-1.771D-02, 1.620D-03, 2.500D-04,-6.000D-05, 5 7.040D-03,-1.113D-02, 1.590D-03, 7.000D-04,-2.000D-04, 0.000D+00, 6-1.710D-03, 2.290D-03, 3.800D-04,-3.500D-04, 4.000D-05, 1.000D-05/ DATA (((CEHLQ(IX,IT,NX,3,2),IX=1,6),IT=1,6),NX=1,2)/ 1 1.008D-01,-7.100D-02, 1.973D-02,-5.710D-03, 2.930D-03,-9.900D-04, 2-5.271D-02,-1.823D-02, 1.792D-02,-6.580D-03, 1.750D-03,-1.550D-03, 3 1.220D-02, 1.763D-02,-8.690D-03,-8.800D-04,-1.160D-03,-2.100D-04, 4-1.190D-03,-7.180D-03, 2.360D-03, 1.890D-03, 7.700D-04, 4.100D-04, 5-9.100D-04, 2.040D-03,-3.100D-04,-1.050D-03,-4.000D-04,-2.400D-04, 6 1.190D-03,-1.700D-04,-2.000D-04, 4.200D-04, 1.700D-04, 1.000D-04, 1 1.081D+00,-1.189D+00, 3.868D-01,-8.617D-02, 1.115D-02,-1.180D-03, 2 9.917D-01,-1.396D+00, 4.998D-01,-1.159D-01, 1.674D-02,-1.720D-03, 3 5.099D-02,-1.338D-01, 9.173D-02,-2.885D-02, 5.890D-03,-6.500D-04, 4-3.178D-02, 5.703D-02,-2.070D-02, 2.440D-03, 1.100D-04,-9.000D-05, 5 8.970D-03,-1.392D-02, 2.050D-03, 6.500D-04,-2.300D-04, 2.000D-05, 6-2.340D-03, 3.010D-03, 5.000D-04,-3.900D-04, 6.000D-05, 1.000D-05/ C...Expansion coefficients for gluon distribution. DATA (((CEHLQ(IX,IT,NX,4,1),IX=1,6),IT=1,6),NX=1,2)/ 1 9.482D-01,-9.578D-01, 1.009D-01,-1.051D-01, 3.456D-02,-3.054D-02, 2-9.627D-01, 5.379D-01, 3.368D-01,-9.525D-02, 1.488D-02,-2.051D-02, 3 4.300D-01,-8.306D-02,-3.372D-01, 4.902D-02,-9.160D-03, 1.041D-02, 4-1.925D-01,-1.790D-02, 2.183D-01, 7.490D-03, 4.140D-03,-1.860D-03, 5 8.183D-02, 1.926D-02,-1.072D-01,-1.944D-02,-2.770D-03,-5.200D-04, 6-3.884D-02,-1.234D-02, 5.410D-02, 1.879D-02, 3.350D-03, 1.040D-03, 1 2.948D+01,-3.902D+01, 1.464D+01,-3.335D+00, 5.054D-01,-5.915D-02, 2 2.559D+01,-3.955D+01, 1.661D+01,-4.299D+00, 6.904D-01,-8.243D-02, 3-1.663D+00, 1.176D+00, 1.118D+00,-7.099D-01, 1.948D-01,-2.404D-02, 4-2.168D-01, 8.170D-01,-7.169D-01, 1.851D-01,-1.924D-02,-3.250D-03, 5 2.088D-01,-4.355D-01, 2.239D-01,-2.446D-02,-3.620D-03, 1.910D-03, 6-9.097D-02, 1.601D-01,-5.681D-02,-2.500D-03, 2.580D-03,-4.700D-04/ DATA (((CEHLQ(IX,IT,NX,4,2),IX=1,6),IT=1,6),NX=1,2)/ 1 2.367D+00, 4.453D-01, 3.660D-01, 9.467D-02, 1.341D-01, 1.661D-02, 2-3.170D+00,-1.795D+00, 3.313D-02,-2.874D-01,-9.827D-02,-7.119D-02, 3 1.823D+00, 1.457D+00,-2.465D-01, 3.739D-02, 6.090D-03, 1.814D-02, 4-1.033D+00,-9.827D-01, 2.136D-01, 1.169D-01, 5.001D-02, 1.684D-02, 5 5.133D-01, 5.259D-01,-1.173D-01,-1.139D-01,-4.988D-02,-2.021D-02, 6-2.881D-01,-3.145D-01, 5.667D-02, 9.161D-02, 4.568D-02, 1.951D-02, 1 3.036D+01,-4.062D+01, 1.578D+01,-3.699D+00, 6.020D-01,-7.031D-02, 2 2.700D+01,-4.167D+01, 1.770D+01,-4.804D+00, 7.862D-01,-1.060D-01, 3-1.909D+00, 1.357D+00, 1.127D+00,-7.181D-01, 2.232D-01,-2.481D-02, 4-2.488D-01, 9.781D-01,-8.127D-01, 2.094D-01,-2.997D-02,-4.710D-03, 5 2.506D-01,-5.427D-01, 2.672D-01,-3.103D-02,-1.800D-03, 2.870D-03, 6-1.128D-01, 2.087D-01,-6.972D-02,-2.480D-03, 2.630D-03,-8.400D-04/ C...Expansion coefficients for strange sea quark distribution. DATA (((CEHLQ(IX,IT,NX,5,1),IX=1,6),IT=1,6),NX=1,2)/ 1 4.968D-02,-4.173D-02, 2.102D-02,-3.270D-03, 3.240D-03,-6.700D-04, 2-6.150D-03,-1.294D-02, 6.740D-03,-6.890D-03, 9.000D-04,-1.510D-03, 3-8.580D-03, 5.050D-03,-4.900D-03,-1.600D-04,-9.400D-04,-1.500D-04, 4 7.840D-03, 1.510D-03, 2.220D-03, 1.400D-03, 7.000D-04, 3.500D-04, 5-4.410D-03,-2.220D-03,-8.900D-04,-8.500D-04,-3.600D-04,-2.000D-04, 6 2.520D-03, 1.840D-03, 4.100D-04, 3.900D-04, 1.600D-04, 9.000D-05, 1 9.235D-01,-1.085D+00, 3.464D-01,-7.210D-02, 9.140D-03,-9.100D-04, 2 9.315D-01,-1.274D+00, 4.512D-01,-9.775D-02, 1.380D-02,-1.310D-03, 3 4.739D-02,-1.296D-01, 8.482D-02,-2.642D-02, 4.760D-03,-5.700D-04, 4-2.653D-02, 4.953D-02,-1.735D-02, 1.750D-03, 2.800D-04,-6.000D-05, 5 6.940D-03,-1.132D-02, 1.480D-03, 6.500D-04,-2.100D-04, 0.000D+00, 6-1.680D-03, 2.340D-03, 4.200D-04,-3.400D-04, 5.000D-05, 1.000D-05/ DATA (((CEHLQ(IX,IT,NX,5,2),IX=1,6),IT=1,6),NX=1,2)/ 1 6.478D-02,-4.537D-02, 1.643D-02,-3.490D-03, 2.710D-03,-6.700D-04, 2-2.223D-02,-2.126D-02, 1.247D-02,-6.290D-03, 1.120D-03,-1.440D-03, 3-1.340D-03, 1.362D-02,-6.130D-03,-7.900D-04,-9.000D-04,-2.000D-04, 4 5.080D-03,-3.610D-03, 1.700D-03, 1.830D-03, 6.800D-04, 4.000D-04, 5-3.580D-03, 6.000D-05,-2.600D-04,-1.050D-03,-3.800D-04,-2.300D-04, 6 2.420D-03, 9.300D-04,-1.000D-04, 4.500D-04, 1.700D-04, 1.100D-04, 1 9.868D-01,-1.171D+00, 3.940D-01,-8.459D-02, 1.124D-02,-1.250D-03, 2 1.001D+00,-1.383D+00, 5.044D-01,-1.152D-01, 1.658D-02,-1.830D-03, 3 4.928D-02,-1.368D-01, 9.021D-02,-2.935D-02, 5.800D-03,-6.600D-04, 4-3.133D-02, 5.785D-02,-2.023D-02, 2.630D-03, 1.600D-04,-8.000D-05, 5 8.840D-03,-1.416D-02, 1.900D-03, 5.800D-04,-2.500D-04, 1.000D-05, 6-2.300D-03, 3.080D-03, 5.500D-04,-3.700D-04, 7.000D-05, 1.000D-05/ C...Expansion coefficients for charm sea quark distribution. DATA (((CEHLQ(IX,IT,NX,6,1),IX=1,6),IT=1,6),NX=1,2)/ 1 9.270D-03,-1.817D-02, 9.590D-03,-6.390D-03, 1.690D-03,-1.540D-03, 2 5.710D-03,-1.188D-02, 6.090D-03,-4.650D-03, 1.240D-03,-1.310D-03, 3-3.960D-03, 7.100D-03,-3.590D-03, 1.840D-03,-3.900D-04, 3.400D-04, 4 1.120D-03,-1.960D-03, 1.120D-03,-4.800D-04, 1.000D-04,-4.000D-05, 5 4.000D-05,-3.000D-05,-1.800D-04, 9.000D-05,-5.000D-05,-2.000D-05, 6-4.200D-04, 7.300D-04,-1.600D-04, 5.000D-05, 5.000D-05, 5.000D-05, 1 8.098D-01,-1.042D+00, 3.398D-01,-6.824D-02, 8.760D-03,-9.000D-04, 2 8.961D-01,-1.217D+00, 4.339D-01,-9.287D-02, 1.304D-02,-1.290D-03, 3 3.058D-02,-1.040D-01, 7.604D-02,-2.415D-02, 4.600D-03,-5.000D-04, 4-2.451D-02, 4.432D-02,-1.651D-02, 1.430D-03, 1.200D-04,-1.000D-04, 5 1.122D-02,-1.457D-02, 2.680D-03, 5.800D-04,-1.200D-04, 3.000D-05, 6-7.730D-03, 7.330D-03,-7.600D-04,-2.400D-04, 1.000D-05, 0.000D+00/ DATA (((CEHLQ(IX,IT,NX,6,2),IX=1,6),IT=1,6),NX=1,2)/ 1 9.980D-03,-1.945D-02, 1.055D-02,-6.870D-03, 1.860D-03,-1.560D-03, 2 5.700D-03,-1.203D-02, 6.250D-03,-4.860D-03, 1.310D-03,-1.370D-03, 3-4.490D-03, 7.990D-03,-4.170D-03, 2.050D-03,-4.400D-04, 3.300D-04, 4 1.470D-03,-2.480D-03, 1.460D-03,-5.700D-04, 1.200D-04,-1.000D-05, 5-9.000D-05, 1.500D-04,-3.200D-04, 1.200D-04,-6.000D-05,-4.000D-05, 6-4.200D-04, 7.600D-04,-1.400D-04, 4.000D-05, 7.000D-05, 5.000D-05, 1 8.698D-01,-1.131D+00, 3.836D-01,-8.111D-02, 1.048D-02,-1.300D-03, 2 9.626D-01,-1.321D+00, 4.854D-01,-1.091D-01, 1.583D-02,-1.700D-03, 3 3.057D-02,-1.088D-01, 8.022D-02,-2.676D-02, 5.590D-03,-5.600D-04, 4-2.845D-02, 5.164D-02,-1.918D-02, 2.210D-03,-4.000D-05,-1.500D-04, 5 1.311D-02,-1.751D-02, 3.310D-03, 5.100D-04,-1.200D-04, 5.000D-05, 6-8.590D-03, 8.380D-03,-9.200D-04,-2.600D-04, 1.000D-05,-1.000D-05/ C...Expansion coefficients for bottom sea quark distribution. DATA (((CEHLQ(IX,IT,NX,7,1),IX=1,6),IT=1,6),NX=1,2)/ 1 9.010D-03,-1.401D-02, 7.150D-03,-4.130D-03, 1.260D-03,-1.040D-03, 2 6.280D-03,-9.320D-03, 4.780D-03,-2.890D-03, 9.100D-04,-8.200D-04, 3-2.930D-03, 4.090D-03,-1.890D-03, 7.600D-04,-2.300D-04, 1.400D-04, 4 3.900D-04,-1.200D-03, 4.400D-04,-2.500D-04, 2.000D-05,-2.000D-05, 5 2.600D-04, 1.400D-04,-8.000D-05, 1.000D-04, 1.000D-05, 1.000D-05, 6-2.600D-04, 3.200D-04, 1.000D-05,-1.000D-05, 1.000D-05,-1.000D-05, 1 8.029D-01,-1.075D+00, 3.792D-01,-7.843D-02, 1.007D-02,-1.090D-03, 2 7.903D-01,-1.099D+00, 4.153D-01,-9.301D-02, 1.317D-02,-1.410D-03, 3-1.704D-02,-1.130D-02, 2.882D-02,-1.341D-02, 3.040D-03,-3.600D-04, 4-7.200D-04, 7.230D-03,-5.160D-03, 1.080D-03,-5.000D-05,-4.000D-05, 5 3.050D-03,-4.610D-03, 1.660D-03,-1.300D-04,-1.000D-05, 1.000D-05, 6-4.360D-03, 5.230D-03,-1.610D-03, 2.000D-04,-2.000D-05, 0.000D+00/ DATA (((CEHLQ(IX,IT,NX,7,2),IX=1,6),IT=1,6),NX=1,2)/ 1 8.980D-03,-1.459D-02, 7.510D-03,-4.410D-03, 1.310D-03,-1.070D-03, 2 5.970D-03,-9.440D-03, 4.800D-03,-3.020D-03, 9.100D-04,-8.500D-04, 3-3.050D-03, 4.440D-03,-2.100D-03, 8.500D-04,-2.400D-04, 1.400D-04, 4 5.300D-04,-1.300D-03, 5.600D-04,-2.700D-04, 3.000D-05,-2.000D-05, 5 2.000D-04, 1.400D-04,-1.100D-04, 1.000D-04, 0.000D+00, 0.000D+00, 6-2.600D-04, 3.200D-04, 0.000D+00,-3.000D-05, 1.000D-05,-1.000D-05, 1 8.672D-01,-1.174D+00, 4.265D-01,-9.252D-02, 1.244D-02,-1.460D-03, 2 8.500D-01,-1.194D+00, 4.630D-01,-1.083D-01, 1.614D-02,-1.830D-03, 3-2.241D-02,-5.630D-03, 2.815D-02,-1.425D-02, 3.520D-03,-4.300D-04, 4-7.300D-04, 8.030D-03,-5.780D-03, 1.380D-03,-1.300D-04,-4.000D-05, 5 3.460D-03,-5.380D-03, 1.960D-03,-2.100D-04, 1.000D-05, 1.000D-05, 6-4.850D-03, 5.950D-03,-1.890D-03, 2.600D-04,-3.000D-05, 0.000D+00/ C...Expansion coefficients for top sea quark distribution. DATA (((CEHLQ(IX,IT,NX,8,1),IX=1,6),IT=1,6),NX=1,2)/ 1 4.410D-03,-7.480D-03, 3.770D-03,-2.580D-03, 7.300D-04,-7.100D-04, 2 3.840D-03,-6.050D-03, 3.030D-03,-2.030D-03, 5.800D-04,-5.900D-04, 3-8.800D-04, 1.660D-03,-7.500D-04, 4.700D-04,-1.000D-04, 1.000D-04, 4-8.000D-05,-1.500D-04, 1.200D-04,-9.000D-05, 3.000D-05, 0.000D+00, 5 1.300D-04,-2.200D-04,-2.000D-05,-2.000D-05,-2.000D-05,-2.000D-05, 6-7.000D-05, 1.900D-04,-4.000D-05, 2.000D-05, 0.000D+00, 0.000D+00, 1 6.623D-01,-9.248D-01, 3.519D-01,-7.930D-02, 1.110D-02,-1.180D-03, 2 6.380D-01,-9.062D-01, 3.582D-01,-8.479D-02, 1.265D-02,-1.390D-03, 3-2.581D-02, 2.125D-02, 4.190D-03,-4.980D-03, 1.490D-03,-2.100D-04, 4 7.100D-04, 5.300D-04,-1.270D-03, 3.900D-04,-5.000D-05,-1.000D-05, 5 3.850D-03,-5.060D-03, 1.860D-03,-3.500D-04, 4.000D-05, 0.000D+00, 6-3.530D-03, 4.460D-03,-1.500D-03, 2.700D-04,-3.000D-05, 0.000D+00/ DATA (((CEHLQ(IX,IT,NX,8,2),IX=1,6),IT=1,6),NX=1,2)/ 1 4.260D-03,-7.530D-03, 3.830D-03,-2.680D-03, 7.600D-04,-7.300D-04, 2 3.640D-03,-6.050D-03, 3.030D-03,-2.090D-03, 5.900D-04,-6.000D-04, 3-9.200D-04, 1.710D-03,-8.200D-04, 5.000D-04,-1.200D-04, 1.000D-04, 4-5.000D-05,-1.600D-04, 1.300D-04,-9.000D-05, 3.000D-05, 0.000D+00, 5 1.300D-04,-2.100D-04,-1.000D-05,-2.000D-05,-2.000D-05,-1.000D-05, 6-8.000D-05, 1.800D-04,-5.000D-05, 2.000D-05, 0.000D+00, 0.000D+00, 1 7.146D-01,-1.007D+00, 3.932D-01,-9.246D-02, 1.366D-02,-1.540D-03, 2 6.856D-01,-9.828D-01, 3.977D-01,-9.795D-02, 1.540D-02,-1.790D-03, 3-3.053D-02, 2.758D-02, 2.150D-03,-4.880D-03, 1.640D-03,-2.500D-04, 4 9.200D-04, 4.200D-04,-1.340D-03, 4.600D-04,-8.000D-05,-1.000D-05, 5 4.230D-03,-5.660D-03, 2.140D-03,-4.300D-04, 6.000D-05, 0.000D+00, 6-3.890D-03, 5.000D-03,-1.740D-03, 3.300D-04,-4.000D-05, 0.000D+00/ C...The following data lines are coefficients needed in the C...Duke, Owens proton structure function parametrizations, see below. C...Expansion coefficients for (up+down) valence quark distribution. DATA ((CDO(IP,IS,1,1),IS=1,6),IP=1,3)/ 1 4.190D-01, 3.460D+00, 4.400D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2 4.000D-03, 7.240D-01,-4.860D+00, 0.000D+00, 0.000D+00, 0.000D+00, 3-7.000D-03,-6.600D-02, 1.330D+00, 0.000D+00, 0.000D+00, 0.000D+00/ DATA ((CDO(IP,IS,1,2),IS=1,6),IP=1,3)/ 1 3.740D-01, 3.330D+00, 6.030D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2 1.400D-02, 7.530D-01,-6.220D+00, 0.000D+00, 0.000D+00, 0.000D+00, 3 0.000D+00,-7.600D-02, 1.560D+00, 0.000D+00, 0.000D+00, 0.000D+00/ C...Expansion coefficients for down valence quark distribution. DATA ((CDO(IP,IS,2,1),IS=1,6),IP=1,3)/ 1 7.630D-01, 4.000D+00, 0.000D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2-2.370D-01, 6.270D-01,-4.210D-01, 0.000D+00, 0.000D+00, 0.000D+00, 3 2.600D-02,-1.900D-02, 3.300D-02, 0.000D+00, 0.000D+00, 0.000D+00/ DATA ((CDO(IP,IS,2,2),IS=1,6),IP=1,3)/ 1 7.610D-01, 3.830D+00, 0.000D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2-2.320D-01, 6.270D-01,-4.180D-01, 0.000D+00, 0.000D+00, 0.000D+00, 3 2.300D-02,-1.900D-02, 3.600D-02, 0.000D+00, 0.000D+00, 0.000D+00/ C...Expansion coefficients for (up+down+strange) sea quark distribution. DATA ((CDO(IP,IS,3,1),IS=1,6),IP=1,3)/ 1 1.265D+00, 0.000D+00, 8.050D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2-1.132D+00,-3.720D-01, 1.590D+00, 6.310D+00,-1.050D+01, 1.470D+01, 3 2.930D-01,-2.900D-02,-1.530D-01,-2.730D-01,-3.170D+00, 9.800D+00/ DATA ((CDO(IP,IS,3,2),IS=1,6),IP=1,3)/ 1 1.670D+00, 0.000D+00, 9.150D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2-1.920D+00,-2.730D-01, 5.300D-01, 1.570D+01,-1.010D+02, 2.230D+02, 3 5.820D-01,-1.640D-01,-7.630D-01,-2.830D+00, 4.470D+01,-1.170D+02/ C...Expansion coefficients for charm sea quark distribution. DATA ((CDO(IP,IS,4,1),IS=1,6),IP=1,3)/ 1 0.000D+00,-3.600D-02, 6.350D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2 1.350D-01,-2.220D-01, 3.260D+00,-3.030D+00, 1.740D+01,-1.790D+01, 3-7.500D-02,-5.800D-02,-9.090D-01, 1.500D+00,-1.130D+01, 1.560D+01/ DATA ((CDO(IP,IS,4,2),IS=1,6),IP=1,3)/ 1 0.000D+00,-1.200D-01, 3.510D+00, 0.000D+00, 0.000D+00, 0.000D+00, 2 6.700D-02,-2.330D-01, 3.660D+00,-4.740D-01, 9.500D+00,-1.660D+01, 3-3.100D-02,-2.300D-02,-4.530D-01, 3.580D-01,-5.430D+00, 1.550D+01/ C...Expansion coefficients for gluon distribution. DATA ((CDO(IP,IS,5,1),IS=1,6),IP=1,3)/ 1 1.560D+00, 0.000D+00, 6.000D+00, 9.000D+00, 0.000D+00, 0.000D+00, 2-1.710D+00,-9.490D-01, 1.440D+00,-7.190D+00,-1.650D+01, 1.530D+01, 3 6.380D-01, 3.250D-01,-1.050D+00, 2.550D-01, 1.090D+01,-1.010D+01/ DATA ((CDO(IP,IS,5,2),IS=1,6),IP=1,3)/ 1 8.790D-01, 0.000D+00, 4.000D+00, 9.000D+00, 0.000D+00, 0.000D+00, 2-9.710D-01,-1.160D+00, 1.230D+00,-5.640D+00,-7.540D+00,-5.960D-01, 3 4.340D-01, 4.760D-01,-2.540D-01,-8.170D-01, 5.500D+00, 1.260D-01/ C...Euler's beta function, requires ordinary Gamma function EULBET(X,Y)=PYGAMM(X)*PYGAMM(Y)/PYGAMM(X+Y) C...Leading order proton parton distributions from Glueck, Reya and C...Vogt. Allowed variable range: 0.25 GeV^2 < Q^2 < 10^8 GeV^2 and C...10^-5 < x < 1. IF(MSTP(51).EQ.11) THEN C...Determine s expansion variable and some x expressions. Q2IN=MIN(1D8,MAX(0.25D0,Q2)) SD=LOG(LOG(Q2IN/0.232D0**2)/LOG(0.25D0/0.232D0**2)) SD2=SD**2 XL=-LOG(X) XS=SQRT(X) C...Evaluate valence, gluon and sea distributions. XFVUD=(0.663D0+0.191D0*SD-0.041D0*SD2+0.031D0*SD**3)* & X**0.326D0*(1D0+(-1.97D0+6.74D0*SD-1.96D0*SD2)*XS+ & (24.4D0-20.7D0*SD+4.08D0*SD2)*X)* & (1D0-X)**(2.86D0+0.70D0*SD-0.02D0*SD2) XFVDD=(0.579D0+0.283D0*SD+0.047D0*SD2)*X**(0.523D0-0.015D0*SD)* & (1D0+(2.22D0-0.59D0*SD-0.27D0*SD2)*XS+(5.95D0-6.19D0*SD+ & 1.55D0*SD2)*X)*(1D0-X)**(3.57D0+0.94D0*SD-0.16D0*SD2) XFGLU=(X**(1.00D0-0.17D0*SD)*((4.879D0*SD-1.383D0*SD2)+ & (25.92D0-28.97D0*SD+5.596D0*SD2)*X+(-25.69D0+23.68D0*SD- & 1.975D0*SD2)*X**2)+SD**0.558D0*EXP(-(0.595D0+2.138D0*SD)+ & SQRT(4.066D0*SD**1.218D0*XL)))* & (1D0-X)**(2.537D0+1.718D0*SD+0.353D0*SD2) XFSEA=(X**(0.412D0-0.171D0*SD)*(0.363D0-1.196D0*X+(1.029D0+ & 1.785D0*SD-0.459D0*SD2)*X**2)*XL**(0.566D0-0.496D0*SD)+ & SD**1.396D0*EXP(-(3.838D0+1.944D0*SD)+SQRT(2.845D0*SD**1.331D0* & XL)))*(1D0-X)**(4.696D0+2.109D0*SD) XFSTR=SD**0.803D0*(1D0+(-3.055D0+1.024D0*SD**0.67D0)*XS+ & (27.4D0-20.0D0*SD**0.154D0)*X)*(1D0-X)**6.22D0* & EXP(-(4.33D0+1.408D0*SD)+SQRT((8.27D0-0.437D0*SD)* & SD**0.563D0*XL))/XL**(2.082D0-0.577D0*SD) IF(SD.LE.0.888D0) THEN XFCHM=0D0 ELSE XFCHM=(SD-0.888D0)**1.01D0*(1.+(4.24D0-0.804D0*SD)*X)* & (1D0-X)**(3.46D0+1.076D0*SD)*EXP(-(4.61D0+1.49D0*SD)+ & SQRT((2.555D0+1.961D0*SD)*SD**0.37D0*XL)) ENDIF IF(SD.LE.1.351D0) THEN XFBOT=0D0 ELSE XFBOT=(SD-1.351D0)*(1D0+1.848D0*X)*(1D0-X)**(2.929D0+ & 1.396D0*SD)*EXP(-(4.71D0+1.514D0*SD)+ & SQRT((4.02D0+1.239D0*SD)*SD**0.51D0*XL)) ENDIF C...Put into output array. XPPR(0)=XFGLU XPPR(1)=XFVDD+XFSEA XPPR(2)=XFVUD-XFVDD+XFSEA XPPR(3)=XFSTR XPPR(4)=XFCHM XPPR(5)=XFBOT XPPR(-1)=XFSEA XPPR(-2)=XFSEA XPPR(-3)=XFSTR XPPR(-4)=XFCHM XPPR(-5)=XFBOT C...Proton parton distributions from Eichten, Hinchliffe, Lane, Quigg. C...Allowed variable range: 5 GeV^2 < Q^2 < 1E8 GeV^2; 1E-4 < x < 1 ELSEIF(MSTP(51).EQ.12.OR.MSTP(51).EQ.13) THEN C...Determine set, Lambda and x and t expansion variables. NSET=MSTP(51)-11 IF(NSET.EQ.1) ALAM=0.2D0 IF(NSET.EQ.2) ALAM=0.29D0 TMIN=LOG(5D0/ALAM**2) TMAX=LOG(1D8/ALAM**2) T=LOG(MAX(1D0,Q2/ALAM**2)) VT=MAX(-1D0,MIN(1D0,(2D0*T-TMAX-TMIN)/(TMAX-TMIN))) NX=1 IF(X.LE.0.1D0) NX=2 IF(NX.EQ.1) VX=(2D0*X-1.1D0)/0.9D0 IF(NX.EQ.2) VX=MAX(-1D0,(2D0*LOG(X)+11.51293D0)/6.90776D0) C...Chebyshev polynomials for x and t expansion. TX(1)=1D0 TX(2)=VX TX(3)=2D0*VX**2-1D0 TX(4)=4D0*VX**3-3D0*VX TX(5)=8D0*VX**4-8D0*VX**2+1D0 TX(6)=16D0*VX**5-20D0*VX**3+5D0*VX TT(1)=1D0 TT(2)=VT TT(3)=2D0*VT**2-1D0 TT(4)=4D0*VT**3-3D0*VT TT(5)=8D0*VT**4-8D0*VT**2+1D0 TT(6)=16D0*VT**5-20D0*VT**3+5D0*VT C...Calculate structure functions. DO 120 KFL=1,6 XQSUM=0D0 DO 110 IT=1,6 DO 100 IX=1,6 XQSUM=XQSUM+CEHLQ(IX,IT,NX,KFL,NSET)*TX(IX)*TT(IT) 100 CONTINUE 110 CONTINUE XQ(KFL)=XQSUM*(1D0-X)**NEHLQ(KFL,NSET) 120 CONTINUE C...Put into output array. XPPR(0)=XQ(4) XPPR(1)=XQ(2)+XQ(3) XPPR(2)=XQ(1)+XQ(3) XPPR(3)=XQ(5) XPPR(4)=XQ(6) XPPR(-1)=XQ(3) XPPR(-2)=XQ(3) XPPR(-3)=XQ(5) XPPR(-4)=XQ(6) C...Special expansion for bottom (threshold effects). IF(MSTP(58).GE.5) THEN IF(NSET.EQ.1) TMIN=8.1905D0 IF(NSET.EQ.2) TMIN=7.4474D0 IF(T.GT.TMIN) THEN VT=MAX(-1D0,MIN(1D0,(2D0*T-TMAX-TMIN)/(TMAX-TMIN))) TT(1)=1D0 TT(2)=VT TT(3)=2D0*VT**2-1D0 TT(4)=4D0*VT**3-3D0*VT TT(5)=8D0*VT**4-8D0*VT**2+1D0 TT(6)=16D0*VT**5-20D0*VT**3+5D0*VT XQSUM=0D0 DO 140 IT=1,6 DO 130 IX=1,6 XQSUM=XQSUM+CEHLQ(IX,IT,NX,7,NSET)*TX(IX)*TT(IT) 130 CONTINUE 140 CONTINUE XPPR(5)=XQSUM*(1D0-X)**NEHLQ(7,NSET) XPPR(-5)=XPPR(5) ENDIF ENDIF C...Special expansion for top (threshold effects). IF(MSTP(58).GE.6) THEN IF(NSET.EQ.1) TMIN=11.5528D0 IF(NSET.EQ.2) TMIN=10.8097D0 TMIN=TMIN+2D0*LOG(PMAS(6,1)/30D0) TMAX=TMAX+2D0*LOG(PMAS(6,1)/30D0) IF(T.GT.TMIN) THEN VT=MAX(-1D0,MIN(1D0,(2D0*T-TMAX-TMIN)/(TMAX-TMIN))) TT(1)=1D0 TT(2)=VT TT(3)=2D0*VT**2-1D0 TT(4)=4D0*VT**3-3D0*VT TT(5)=8D0*VT**4-8D0*VT**2+1D0 TT(6)=16D0*VT**5-20D0*VT**3+5D0*VT XQSUM=0D0 DO 160 IT=1,6 DO 150 IX=1,6 XQSUM=XQSUM+CEHLQ(IX,IT,NX,8,NSET)*TX(IX)*TT(IT) 150 CONTINUE 160 CONTINUE XPPR(6)=XQSUM*(1D0-X)**NEHLQ(8,NSET) XPPR(-6)=XPPR(6) ENDIF ENDIF C...Proton parton distributions from Duke, Owens. C...Allowed variable range: 4 GeV^2 < Q^2 < approx 1E6 GeV^2. ELSEIF(MSTP(51).EQ.14.OR.MSTP(51).EQ.15) THEN C...Determine set, Lambda and s expansion parameter. NSET=MSTP(51)-13 IF(NSET.EQ.1) ALAM=0.2D0 IF(NSET.EQ.2) ALAM=0.4D0 Q2IN=MIN(1D6,MAX(4D0,Q2)) SD=LOG(LOG(Q2IN/ALAM**2)/LOG(4D0/ALAM**2)) C...Calculate structure functions. DO 180 KFL=1,5 DO 170 IS=1,6 TS(IS)=CDO(1,IS,KFL,NSET)+CDO(2,IS,KFL,NSET)*SD+ & CDO(3,IS,KFL,NSET)*SD**2 170 CONTINUE IF(KFL.LE.2) THEN XQ(KFL)=X**TS(1)*(1D0-X)**TS(2)*(1D0+TS(3)*X)/(EULBET(TS(1), & TS(2)+1D0)*(1D0+TS(3)*TS(1)/(TS(1)+TS(2)+1D0))) ELSE XQ(KFL)=TS(1)*X**TS(2)*(1D0-X)**TS(3)*(1D0+TS(4)*X+ & TS(5)*X**2+TS(6)*X**3) ENDIF 180 CONTINUE C...Put into output arrays. XPPR(0)=XQ(5) XPPR(1)=XQ(2)+XQ(3)/6D0 XPPR(2)=3D0*XQ(1)-XQ(2)+XQ(3)/6D0 XPPR(3)=XQ(3)/6D0 XPPR(4)=XQ(4) XPPR(-1)=XQ(3)/6D0 XPPR(-2)=XQ(3)/6D0 XPPR(-3)=XQ(3)/6D0 XPPR(-4)=XQ(4) ENDIF RETURN END