--- /dev/null
+//--------------------------------------------------------------------------
+//
+// Environment:
+// This software is part of the EvtGen package developed jointly
+// for the BaBar and CLEO collaborations. If you use all or part
+// of it, please give an appropriate acknowledgement.
+//
+// Copyright Information:
+// Copyright (C) 1998 Caltech, UCSB
+//
+// Module: EvtBaryonVminusAFF.cc
+//
+// Description: Routine to implement semileptonic form factors
+// according to the model BaryonVminusA
+//
+// Modification history:
+//
+// R.J. Tesarek May 28, 2004 Module created
+// Karen Gibson 1/20/2006 Module updated for 1/2+->1/2+,
+// 1/2+->1/2-, 1/2+->3/2- Lambda decays
+//
+//--------------------------------------------------------------------------
+#include "EvtGenBase/EvtPatches.hh"
+#include "EvtGenBase/EvtReport.hh"
+#include "EvtGenModels/EvtBaryonPCRFF.hh"
+#include "EvtGenBase/EvtPDL.hh"
+#include "EvtGenBase/EvtId.hh"
+#include "EvtGenBase/EvtIdSet.hh"
+#include "EvtGenBase/EvtConst.hh"
+#include <string>
+#include <math.h>
+#include <stdlib.h>
+using std::endl;
+
+void EvtBaryonPCRFF::getdiracff(EvtId parent, EvtId daught,
+ double q2, double /* mass */ ,
+ double *f1, double *f2, double *f3,
+ double *g1, double *g2, double *g3 ) {
+
+ // Baryons (partial list 5/28/04)
+ static EvtId LAMCP=EvtPDL::getId("Lambda_c+");
+ static EvtId LAMCM=EvtPDL::getId("anti-Lambda_c-");
+ static EvtId LAMC1P=EvtPDL::getId("Lambda_c(2593)+");
+ static EvtId LAMC1M=EvtPDL::getId("anti-Lambda_c(2593)-");
+ static EvtId LAMB=EvtPDL::getId("Lambda_b0");
+ static EvtId LAMBB=EvtPDL::getId("anti-Lambda_b0");
+
+ double F1, F2, F3, G1, G2, G3;
+
+ if( parent==LAMB || parent==LAMBB ) {
+ // Implement constituent quark model form factors predicted
+ // by M. Pervin, W. Roberst, and S. Capstick, Phys. Rev. C72, 035201 (2005)
+
+ if( daught==LAMCP|| daught==LAMCM ) {
+
+ // Parameters needed in the calculation;
+ double mQ = 5.28;
+ double mq = 1.89;
+ double md = 0.40;
+ double MLamB = EvtPDL::getMass(parent);
+ double MLamC = EvtPDL::getMass(daught);
+
+ double aL = 0.59;
+ double aLp = 0.55;
+
+ double aL2 = aL*aL;
+ double aLp2 = aLp*aLp;
+ double aLLp2 = 0.5*(aL2+aLp2);
+
+ // relativistic correction factor
+ double k2 = 1.0;
+ double rho2 = 3.*md*md/(2.*k2*aLLp2);
+
+ // w = scalar product of the 4 velocities of the Lb and Lc.
+ double w = 0.5*(MLamB*MLamB + MLamC*MLamC - q2)/MLamB/MLamC;
+
+ double I = pow(aL*aLp/aLLp2, 1.5)*exp(-rho2*(w*w-1.));
+
+ // Calculate the form factors
+ F1 = I*( 1.0 + (md/aLLp2)*( (aLp2/mq)+(aL2/mQ) ) );
+ F2 = -I*( (md/mq)*(aLp2/aLLp2) - aL2*aLp2/(4.*aLLp2*mq*mQ) );
+ F3 = -I*md*aL2/(mQ*aLLp2);
+
+ G1 = I*( 1.0 - (aL2*aLp2)/(12.*aLLp2*mq*mQ) );
+ G2 = -I*( md*aLp2/(mq*aLLp2)
+ + (aL2*aLp2)/(12.*aLLp2*mq*mQ)*(1.+12.*md*md/aLLp2) );
+ G3 = I*( md*aL2/(mQ*aLLp2) + md*md*aL2*aLp2/(mq*mQ*aLLp2*aLLp2) );
+
+ // Set form factors to be passed to the amplitude calc.
+ *f1 = F1;
+ *f2 = F2;
+ *f3 = F3;
+ *g1 = G1;
+ *g2 = G2;
+ *g3 = G3;
+
+ }
+
+ else if( daught==LAMC1P || daught==LAMC1M ) {
+
+ double mQ = 5.28;
+ double mq = 1.89;
+ double md = 0.40;
+ double MLamB = EvtPDL::getMass(parent);
+ double MLamC = EvtPDL::getMass(daught);
+
+ double aL = 0.59;
+ double aLp = 0.47;
+
+ double aL2 = aL*aL;
+ double aLp2 = aLp*aLp;
+ double aLLp2 = 0.5*(aL2+aLp2);
+
+ // relativistic correction factor
+ double k2 = 1.0;
+ double rho2 = 3.*md*md/(2.*k2*aLLp2);
+
+ // w = scalar product of the 4 velocities of the Lb and Lc.
+ double w = 0.5*(MLamB*MLamB + MLamC*MLamC - q2)/MLamB/MLamC;
+
+ double I = pow(aL*aLp/aLLp2, 2.5)*exp(-rho2*(w*w-1.));
+
+ // Calculate the form factors
+ F1 = I*aL/6.0*( 3.0/mq - 1.0/mQ );
+ F2 = -I*( 2.0*md/aL - aL/(2.0*mq) + 2.*md*md*aL/(mQ*aLLp2)
+ - (md*aL/(6.*mq*mQ*aLLp2))*( 3.*aL2 - 2.*aLp2));
+ F3 = I*2.*md*md*aL/(mQ*aLLp2);
+
+ G1 = I*( 2.0*md/aL - aL/(6.*mQ)
+ + (md*aL/(6.*mq*mQ*aLLp2))*( 3.*aL2 - 2.*aLp2));
+ G2 = I*( -2.*md/aL + aL/(2.*mq) + aL/(3.*mQ) );
+ G3 = I*aL/(3.*mQ)*( 1.0 - (md/(2.*mq*aLLp2))*( 3.*aL2 - 2.*aLp2));
+
+ // Set form factors to be passed to the amplitude calc.
+ *f1 = F1;
+ *f2 = F2;
+ *f3 = F3;
+ *g1 = G1;
+ *g2 = G2;
+ *g3 = G3;
+ }
+ }
+
+ else {
+ *f1 = 1.0;
+ *f2 = 1.0;
+ *f3 = 0.0;
+ *g1 = 1.0;
+ *g2 = 1.0;
+ *g3 = 0.0;
+ }
+
+ return ;
+}
+
+
+void EvtBaryonPCRFF::getraritaff( EvtId parent, EvtId daught,
+ double q2, double /* mass */,
+ double *f1, double *f2, double *f3, double *f4,
+ double *g1, double *g2, double *g3, double *g4 ) {
+
+ // Baryons (partial list 5/28/04)
+ static EvtId LAMB=EvtPDL::getId("Lambda_b0");
+ static EvtId LAMBB=EvtPDL::getId("anti-Lambda_b0");
+ static EvtId LAMC2P=EvtPDL::getId("Lambda_c(2625)+");
+ static EvtId LAMC2M=EvtPDL::getId("anti-Lambda_c(2625)-");
+
+ double F1, F2, F3, F4, G1, G2, G3, G4;
+
+ if( parent==LAMB || parent==LAMBB ) {
+ // Implement constituent quark model form factors predicted
+ // by M. Pervin, W. Roberst, and S. Capstick, Phys. Rev. C72, 035201 (2005)
+
+ if( daught==LAMC2P|| daught==LAMC2M ) {
+
+ double mQ = 5.28;
+ double mq = 1.89;
+ double md = 0.40;
+ double MLamB = EvtPDL::getMass(parent);
+ double MLamC = EvtPDL::getMass(daught);
+
+ double aL = 0.59;
+ double aLp = 0.47;
+
+ double aL2 = aL*aL;
+ double aLp2 = aLp*aLp;
+ double aLLp2 = 0.5*(aL2+aLp2);
+
+ // relativistic correction factor
+ double k2 = 1.0;
+ double rho2 = 3.*md*md/(2.*k2*aLLp2);
+
+ // w = scalar product of the 4 velocities of the Lb and Lc.
+ double w = 0.5*(MLamB*MLamB + MLamC*MLamC - q2)/MLamB/MLamC;
+
+ double I = -(1./sqrt(3.))*pow(aL*aLp/aLLp2, 2.5)*exp(-rho2*(w*w-1.));
+
+ // Calculate the form factors
+ F1 = I*3.0*md/aL*( 1.0 + (md/aLLp2)*( (aLp2/mq)+(aL2/mQ) ) );
+ F2 = -I*( (3.*md*md/mq)*(aLp2/(aLLp2*aL2)) - 5.*aL*aLp2*md/(4.*aLLp2*mq*mQ) );
+ F3 = -I*( 3.*md*md*aL/(mQ*aLLp2) + aL/(2.*mQ) );
+ F4 = I*aL/mQ;
+
+ G1 = I*( 3.0*md/aL - (aL/(2.*mQ))*(1. + 3.*md*aLp2/(2.*aLLp2*mq) ) );
+ G2 = -I*( (3.*md*md/mq)*(aLp2/(aLLp2*aL)) + aL*aLp2*md/(4.*aLLp2*aLLp2*mq*mQ)*(aLLp2+12.*md*md) );
+ G3 = I*aL/(mQ*aLLp2)*( aLLp2/2. + 3.*md*md + aLp2*md/(mq*aLLp2)*(aLLp2+6.*md*md) );
+ G4 = -I*( aL/mQ + md/(mq*mQ)*aLp2*aL/aLLp2 );
+
+ // Set form factors to be passed to the amplitude calc.
+ *f1 = F1;
+ *f2 = F2;
+ *f3 = F3;
+ *f4 = F4;
+ *g1 = G1;
+ *g2 = G2;
+ *g3 = G3;
+ *g4 = G4;
+ }
+ }
+
+ else {
+ *f1 = 1.0;
+ *f2 = 1.0;
+ *f3 = 0.0;
+ *f4 = 0.0;
+ *g1 = 1.0;
+ *g2 = 1.0;
+ *g3 = 0.0;
+ *g4 = 0.0;
+
+ }
+
+ return ;
+
+
+}
+
+void EvtBaryonPCRFF::getscalarff(EvtId, EvtId, double, double, double*, double*) {
+
+ report(ERROR,"EvtGen") << "Not implemented :getscalarff in EvtBaryonPCRFF.\n";
+ ::abort();
+
+}
+
+void EvtBaryonPCRFF::getvectorff(EvtId, EvtId, double, double, double*, double*,
+ double*, double*) {
+
+ report(ERROR,"EvtGen") << "Not implemented :getvectorff in EvtBaryonPCRFF.\n";
+ ::abort();
+
+}
+
+void EvtBaryonPCRFF::gettensorff(EvtId, EvtId, double, double, double*, double*,
+ double*, double*) {
+
+ report(ERROR,"EvtGen") << "Not implemented :gettensorff in EvtBaryonPCRFF.\n";
+ ::abort();
+
+}
+
+void EvtBaryonPCRFF::getbaryonff(EvtId, EvtId, double, double, double*,
+ double*, double*, double*){
+
+ report(ERROR,"EvtGen") << "Not implemented :getbaryonff in EvtBaryonPCRFF.\n";
+ ::abort();
+
+}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff