EvtbTosllBallFF.cpp

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#include "EvtGenModels/EvtbTosllBallFF.hh"
 
#include "EvtGenBase/EvtPDL.hh"
 
#include <cmath>
 
EvtbTosllBallFF::EvtbTosllBallFF( int ffmodel )
{
    m_theFFModel = ffmodel;
}
 
void EvtbTosllBallFF::getScalarFF( EvtId parent, EvtId daught, double t,
                                   double /*mass*/, double& fp, double& f0,
                                   double& ft )
{
    int model = m_theFFModel;
 
    double m = EvtPDL::getMeanMass( parent );
    double md = EvtPDL::getMeanMass( daught );
 
    double shat = t / ( m * m );
    double shat2 = shat * shat;
    double shat3 = shat2 * shat;
 
    if ( daught == EvtPDL::getId( std::string( "K+" ) ) ||
         daught == EvtPDL::getId( std::string( "K-" ) ) ||
         daught == EvtPDL::getId( std::string( "K_S0" ) ) ||
         daught == EvtPDL::getId( std::string( "K0" ) ) ||
         daught == EvtPDL::getId( std::string( "anti-K0" ) ) ||
         daught == EvtPDL::getId( std::string( "K_L0" ) ) ) {
        // B --> K form factors
        if ( model == 1 ) {
            //this is Ali-Ball '01 (or really Ali-Ball'99 minimum allowed)
            fp = 0.278 * exp( 1.568 * shat + 0.470 * shat2 + 0.885 * shat3 );
            f0 = 0.278 * exp( 0.740 * shat + 0.080 * shat2 + 0.425 * shat3 );
            ft = 0.300 * exp( 1.600 * shat + 0.501 * shat2 + 0.796 * shat3 );
        }
        if ( model == 2 ) {
            //this is Ali-Ball '99 (central values)
            fp = 0.319 * exp( 1.465 * shat + 0.372 * shat2 + 0.782 * shat3 );
            f0 = 0.319 * exp( 0.633 * shat - 0.095 * shat2 + 0.591 * shat3 );
            ft = 0.355 * exp( 1.478 * shat + 0.373 * shat2 + 0.700 * shat3 );
        }
        if ( model == 3 ) {
            //QCD sum rules (Colangelo et al)
            fp = 0.25 / ( 1. - t / ( 5.0 * 5.0 ) );
            f0 = 0.25 / ( 1. - t / ( 7.0 * 7.0 ) );
            ft = -0.14 /
                 ( ( 1.0 - t / ( 5.0 * 5.0 ) ) * ( 1.0 - t / ( 7.0 * 7.0 ) ) );
        }
        if ( model == 4 ) {
            // Quark model  (Melikhov et al - hep-ph/9711362)
            fp = 0.36 / ( 1. - 0.048 * t + 0.00063 * t * t );
            double fm = -0.30 / ( 1. - 0.050 * t + 0.00061 * t * t );
            f0 = fp + fm * ( t / ( m * m - md * md ) );
            ft = -( m + md ) * 0.06 / ( 1 - 0.049 * t + 0.00064 * t * t );
        }
        if ( model == 5 ) {
            fp = 0.341 / ( 1. - 1.41 * shat + 0.406 * shat * shat );
            f0 = 0.341 / ( 1. - 0.41 * shat - 0.361 * shat * shat );
            ft = 0.374 / ( 1. - 1.42 * shat + 0.434 * shat * shat );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 "set 2" (mb = 4.8)
            fp = ( 0.1616 / ( 1. - ( t / 29.30 ) ) ) +
                 ( 0.1730 / ( 1. - ( t / 29.30 ) ) / ( 1. - ( t / 29.30 ) ) );
            f0 = ( 0.3302 / ( 1. - ( t / 37.46 / 37.46 ) ) );
            ft = ( 0.1614 / ( 1. - ( t / 29.30 ) ) ) +
                 ( 0.1981 / ( 1. - ( t / 29.30 ) ) / ( 1. - ( t / 29.30 ) ) );
        }
        if ( model == 7 ) {
            // Ball-Zwicky LCSR '05 "set 4" (mb = 4.6)
            fp = ( 0.1903 / ( 1. - ( t / 29.30 ) ) ) +
                 ( 0.1478 / ( 1. - ( t / 29.30 ) ) / ( 1. - ( t / 29.30 ) ) );
            f0 = ( 0.3338 / ( 1. - ( t / 38.98 / 38.98 ) ) );
            ft = ( 0.1851 / ( 1. - ( t / 29.30 ) ) ) +
                 ( 0.1905 / ( 1. - ( t / 29.30 ) ) / ( 1. - ( t / 29.30 ) ) );
        }
    } else if ( daught == EvtPDL::getId( std::string( "pi+" ) ) ||
                daught == EvtPDL::getId( std::string( "pi-" ) ) ||
                daught == EvtPDL::getId( std::string( "pi0" ) ) ) {
        if ( model == 1 ) {
            // B --> pi form factors from Ball-Zwicky'01 (tabulated in hep-ph/0306251)
            fp = 0.261 / ( 1. - 2.03 * shat + 1.293 * shat * shat );
            f0 = 0.261 / ( 1. - 0.27 * shat - 0.752 * shat * shat );
            ft = 0.296 / ( 1. - 1.28 * shat + 0.193 * shat * shat );
        }
 
        // The following two (2) and (3) should preferably be replaced with
        // something better. ft not provided by the papers, and the ft formula
        // (from Colangelo'96 (hep-ph/9510403v2) equation (5.1)) seem to be no good.
        //  if (model == 2) {
        //    // LatticeQCD: Okamoto'04
        //    // ... with f_T from eq. (5.1) of Colangelo'95
        //    fp = 0.23/((1.-shat)*(1.-0.63*shat));
        //    f0 = 0.23/((1.-shat)/1.18);
        //    ft = ( -(m+md)/(2*m) )/ (fp - (m*m-md*md) * ((f0-fp)/t) );
        //  }
        //  if (model == 3) {
        //    // LatticeQCD: Shigemitsu'04
        //    // ... with f_T from eq. (5.1) of Colangelo'95
        //    fp = 0.42*(1.0-0.41)/((1.-shat)*(1.-0.63*shat));
        //    f0 = 0.42*(1.0-0.41)/((1.-shat)/1.18);
        //    ft = ( -(m+md)/(2*m) )/ (fp - (m*m-md*md) * ((f0-fp)/t) );
        //   }
 
        if ( model == 4 ) {
            // Quark model - B -> pi set 1 (Melikhov-Nikitin'96)
            fp = 0.29 / pow( ( 1. - t / ( 6.48 * 6.48 ) ), 2.54 );
            double fm = -0.26 / pow( ( 1. - t / ( 6.34 * 6.34 ) ), 2.49 );
            f0 = fp + fm * ( t / ( m * m - md * md ) );
            ft = -( m + md ) * 0.05 / pow( ( 1. - t / ( 6.47 * 6.47 ) ), 2.50 );
        }
        if ( model == 5 ) {
            // Melikhov-Stech '00. (hep-ph/0001113)
            // relativistic dispersion approach based on constituent quark picture
            fp = 0.29 / ( ( 1. - shat ) * ( 1. - 0.48 * shat ) );
            f0 = 0.29 / ( 1. - 0.76 * shat + 0.28 * shat * shat );
            ft = 0.28 / ( ( 1. - shat ) * ( 1. - 0.48 * shat ) );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 "set 2" (mb = 4.8)
            fp = ( 0.744 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -0.486 / ( 1. - ( t / 40.73 ) ) );
            f0 = ( 0.258 / ( 1. - ( t / 33.81 ) ) );
            ft = ( 1.387 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -1.134 / ( 1. - ( t / 32.22 ) ) );
        }
        if ( model == 7 ) {
            // Ball-Zwicky LCSR '05 "set 4" (mb = 4.6)
            fp = ( 0.944 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -0.669 / ( 1. - ( t / 34.27 ) ) );
            f0 = ( 0.270 / ( 1. - ( t / 33.63 ) ) );
            ft = ( 0.152 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( 0.122 / ( 1. - ( t / 28.40 ) ) / ( 1. - ( t / 28.40 ) ) );
        }
    } else if ( daught == EvtPDL::getId( std::string( "eta" ) ) ||
                daught == EvtPDL::getId( std::string( "eta'" ) ) ) {
        if ( model == 1 ) {
            // B --> eta form factors
            fp = 0.261 / ( 1. - 2.03 * shat + 1.293 * shat * shat );
            f0 = 0.261 / ( 1. - 0.27 * shat - 0.752 * shat * shat );
            ft = 0.296 / ( 1. - 1.28 * shat + 0.193 * shat * shat );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 "set 2" (mb = 4.8)
            fp = ( 0.1220 / ( 1. - ( t / 28.40 ) ) ) +
                 ( 0.1553 / ( 1. - ( t / 28.40 ) ) / ( 1. - ( t / 28.40 ) ) );
            f0 = ( 0.2734 / ( 1. - ( t / 31.03 / 31.03 ) ) );
            ft = ( 0.1108 / ( 1. - ( t / 28.40 ) ) ) +
                 ( 0.1752 / ( 1. - ( t / 28.40 ) ) / ( 1. - ( t / 28.40 ) ) );
        }
        if ( model == 7 ) {
            // Ball-Zwicky LCSR '05 "set 2" (mb = 4.8)
            fp = ( 0.1380 / ( 1. - ( t / 28.40 ) ) ) +
                 ( 0.1462 / ( 1. - ( t / 28.40 ) ) / ( 1. - ( t / 28.40 ) ) );
            f0 = ( 0.2799 / ( 1. - ( t / 30.46 / 30.46 ) ) );
            ft = ( 0.1160 / ( 1. - ( t / 28.40 ) ) ) +
                 ( 0.1841 / ( 1. - ( t / 28.40 ) ) / ( 1. - ( t / 28.40 ) ) );
        }
    }
 
    // cout << "shat "<<shat<<"\t"<<"fp "<<fp<<"\t"<<"f0 "<<f0<<"\t"
    //    <<"ft "<<ft<<endl;
}
 
void EvtbTosllBallFF::getVectorFF( EvtId parent, EvtId daught, double t,
                                   double /*mass*/, double& a1, double& a2,
                                   double& a0, double& v, double& t1,
                                   double& t2, double& t3 )
{
    int model = m_theFFModel;
 
    double m = EvtPDL::getMeanMass( parent );
    double md = EvtPDL::getMeanMass( daught );
 
    double shat = t / ( m * m );
    double shat2 = shat * shat;
 
    if (
        // B_s decay form factors
        parent == EvtPDL::getId( std::string( "B_s0" ) ) ||
        parent == EvtPDL::getId( std::string( "anti-B_s0" ) ) ) {
        if (
            // B_s --> K* form factors
            daught == EvtPDL::getId( std::string( "K*0" ) ) ||
            daught == EvtPDL::getId( std::string( "anti-K*0" ) ) ) {
            if ( model == 6 ) {
                // Ball-Zwicky LCSR '05 (mb = 4.8)
                a1 = 0.231 / ( 1. - ( t / 32.94 ) );
                a2 = ( -0.011 / ( 1. - ( t / 40.14 ) ) ) +
                     ( 0.192 / ( 1. - ( t / 40.14 ) ) / ( 1. - ( t / 40.14 ) ) );
                a0 = ( 2.813 / ( 1. - ( t / ( 5.37 * 5.37 ) ) ) ) +
                     ( -2.509 / ( 1. - ( t / 31.58 ) ) );
                v = ( 2.351 / ( 1. - ( t / ( 5.42 * 5.42 ) ) ) ) +
                    ( -2.039 / ( 1. - ( t / 33.10 ) ) );
                t1 = ( 2.047 / ( 1. - ( t / ( 5.42 * 5.42 ) ) ) ) +
                     ( -1.787 / ( 1 - ( t / 32.83 ) ) );
                t2 = 0.260 / ( 1. - ( t / 33.01 ) );
                double t3tilde = ( 0.043 / ( 1. - ( t / 39.38 ) ) ) +
                                 ( 0.217 / ( 1. - ( t / 39.38 ) ) /
                                   ( 1. - ( t / 39.38 ) ) );
                t3 = 0.0;
                if ( fabs( t ) > 1e-10 ) {
                    t3 = ( m * m - md * md ) * ( t3tilde - t2 ) / t;
                }
            }
        }
 
        else if (
            // B_s --> phi form factors
            daught == EvtPDL::getId( std::string( "phi" ) ) ) {
            if ( model == 6 ) {
                // Ball-Zwicky LCSR '05 (mb = 4.8)
                a1 = 0.308 / ( 1. - ( t / 36.54 ) );
                a2 = ( -0.054 / ( 1. - ( t / 48.94 ) ) ) +
                     ( 0.288 / ( 1. - ( t / 48.94 ) ) / ( 1. - ( t / 48.94 ) ) );
                a0 = ( 3.310 / ( 1. - ( t / ( 5.28 * 5.28 ) ) ) ) +
                     ( -2.835 / ( 1. - ( t / 31.57 ) ) );
                v = ( 1.484 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                    ( -1.049 / ( 1. - ( t / 39.52 ) ) );
                t1 = ( 1.303 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                     ( -0.954 / ( 1 - ( t / 38.28 ) ) );
                t2 = 0.348 /
                     ( 1. - ( t / 37.21 ) );    //0.349 caused a pole in T3 for q2 -> 0. 0.348 has correct behaviour
                double t3tilde = ( 0.027 / ( 1. - ( t / 45.56 ) ) ) +
                                 ( 0.321 / ( 1. - ( t / 45.56 ) ) /
                                   ( 1. - ( t / 45.56 ) ) );
                t3 = 0.0;
                if ( fabs( t ) > 1e-10 ) {
                    t3 = ( m * m - md * md ) * ( t3tilde - t2 ) / t;
                }
            }
        }
    } else if ( daught == EvtPDL::getId( std::string( "K*+" ) ) ||
                daught == EvtPDL::getId( std::string( "K*-" ) ) ||
                daught == EvtPDL::getId( std::string( "K*0" ) ) ||
                daught == EvtPDL::getId( std::string( "anti-K*0" ) ) ||
                daught == EvtPDL::getId( std::string( "K_1+" ) ) ||
                daught == EvtPDL::getId( std::string( "K_1-" ) )
 
    ) {
        if ( model == 1 ) {
            //this is Ali-Ball '01
            a1 = 0.294 * exp( 0.656 * shat + 0.456 * shat2 );
            a2 = 0.246 * exp( 1.237 * shat + 0.822 * shat2 );
            a0 = 0.412 * exp( 1.543 * shat + 0.954 * shat2 );
            v = 0.399 * exp( 1.537 * shat + 1.123 * shat2 );
 
            t1 = 0.334 * exp( 1.575 * shat + 1.140 * shat2 );
            t2 = 0.334 * exp( 0.562 * shat + 0.481 * shat2 );
            t3 = 0.234 * exp( 1.230 * shat + 1.089 * shat2 );
        }
        if ( model == 2 ) {
            //this is Ali-Ball '99
            a1 = 0.337 * exp( 0.602 * shat + 0.258 * shat2 );
            a2 = 0.282 * exp( 1.172 * shat + 0.567 * shat2 );
            a0 = 0.471 * exp( 1.505 * shat + 0.710 * shat2 );
            v = 0.457 * exp( 1.482 * shat + 1.015 * shat2 );
 
            t1 = 0.379 * exp( 1.519 * shat + 1.030 * shat2 );
            t2 = 0.379 * exp( 0.517 * shat + 0.426 * shat2 );
            t3 = 0.260 * exp( 1.129 * shat + 1.128 * shat2 );
        }
        if ( model == 3 ) {
            //QCD sum rules (Colangelo et al)
            // JJH - Changed in accordance with erratum (Phys. Rev. D 57, 3186 (1998))
            a1 = 0.37 * ( 1 - 0.023 * t );
            a2 = 0.40 * ( 1 + 0.034 * t );
            a0 = 0.3 / ( 1. - t / ( 4.8 * 4.8 ) );
            v = 0.47 / ( 1. - t / ( 5.0 * 5.0 ) );
 
            t1 = 0.19 / ( 1. - t / ( 5.3 * 5.3 ) );
            t2 = 0.19 * ( 1. - 0.02 * t );
            t3 = 0.3 * ( 1. + 0.01 * t );
        }
 
        if ( model == 4 ) {
            // Quark model  (Melikhov et al)
            a1 = 1.6 / ( 1 - 0.0288 * t + 0.00028 * t * t );
            a1 = a1 / ( m + md );
            a2 = ( m + md ) * 0.036 / ( 1. - 0.053 * t + 0.00082 * t * t );
            double aminus = 0.041 / ( 1. - 0.055 * t + 0.00088 * t * t );
            double f = 1.60 / ( 1. - 0.0288 * t + 0.00028 * t * t );
            double aplus = -0.036 / ( 1. - 0.053 * t + 0.00082 * t * t );
            a0 = ( t * aminus + f + ( m * m - md * md ) * aplus ) / ( 2.0 * md );
            v = ( m + md ) * 0.048 / ( 1. - 0.057 * t + 0.00085 * t * t );
 
            t1 = 0.28 / ( 1. - 0.058 * t + 0.0009 * t * t );
            double gplus = -0.28 / ( 1. - 0.058 * t + 0.0009 * t * t );
            double gminus = 0.24 / ( 1. - 0.059 * t + 0.00096 * t * t );
            t2 = -gplus - ( t * gminus ) / ( m * m - md * md );
            double h = 0.0037 / ( 1. - 0.075 * t + 0.0016 * t * t );
            t3 = ( m + md ) * ( m + md ) *
                 ( ( gminus / ( m * m - md * md ) - h / 2. ) );
        }
        if ( model == 5 ) {
            a1 = 0.337 / ( 1. - 0.60 * shat - 0.023 * shat * shat );
            a2 = 0.283 / ( 1. - 1.18 * shat + 0.281 * shat * shat );
            a0 = 0.470 / ( 1. - 1.55 * shat + 0.680 * shat * shat );
            v = 0.458 / ( 1. - 1.55 * shat + 0.575 * shat * shat );
            t1 = 0.379 / ( 1. - 1.59 * shat + 0.615 * shat * shat );
            t2 = 0.379 / ( 1. - 0.49 * shat - 0.241 * shat * shat );
            t3 = 0.261 / ( 1. - 1.20 * shat + 0.098 * shat * shat );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 (mb = 4.8)
            a1 = 0.290 / ( 1. - ( t / 40.38 ) );
            a2 = ( -0.084 / ( 1. - ( t / 52.00 ) ) ) +
                 ( 0.342 / ( 1. - ( t / 52.00 ) ) / ( 1. - ( t / 52.00 ) ) );
            a0 = ( 1.364 / ( 1. - ( t / ( 5.28 * 5.28 ) ) ) ) +
                 ( -0.990 / ( 1. - ( t / 36.78 ) ) );
            v = ( 0.923 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                ( -0.511 / ( 1. - ( t / 49.40 ) ) );
            t1 = ( 0.823 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -0.491 / ( 1 - ( t / 46.31 ) ) );
            t2 = 0.332 /
                 ( 1. - ( t / 41.41 ) );    //0.333 caused a pole in T3 for q2 -> 0. 0.332 has correct behaviour
            double t3tilde = ( -0.036 / ( 1. - ( t / 48.10 ) ) ) +
                             ( 0.368 / ( 1. - ( t / 48.10 ) ) /
                               ( 1. - ( t / 48.10 ) ) );
            t3 = 0.0;
            if ( fabs( t ) > 1e-10 ) {
                t3 = ( m * m - md * md ) * ( t3tilde - t2 ) / t;
            }
        }
        if ( model == 8 ) {
            // Khodjamirian et al. LCSR '10
            double taup = ( 5.280 + 0.892 ) * ( 5.280 + 0.892 );
            double taum = ( 5.280 - 0.892 ) * ( 5.280 - 0.892 );
            double tau0 = taup - ( sqrt( taup - taum ) * sqrt( taup ) );
            double z = ( sqrt( taup - t ) - sqrt( taup - tau0 ) ) /
                       ( sqrt( taup - t ) + sqrt( taup - tau0 ) );
            double z0 = ( sqrt( taup ) - sqrt( taup - tau0 ) ) /
                        ( sqrt( taup ) + sqrt( taup - tau0 ) );
            a1 = ( 0.25 / ( 1 - ( t / ( 5.829 * 5.829 ) ) ) ) *
                 ( 1 + 0.34 * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            a2 = ( 0.23 / ( 1 - ( t / ( 5.829 * 5.829 ) ) ) ) *
                 ( 1 +
                   ( -0.85 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            a0 = ( 0.29 / ( 1 - ( t / ( 5.366 * 5.366 ) ) ) ) *
                 ( 1 +
                   ( -18.2 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            v = ( 0.36 / ( 1 - ( t / ( 5.412 * 5.412 ) ) ) ) *
                ( 1 + ( -4.8 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            t1 = ( 0.31 / ( 1 - ( t / ( 5.412 * 5.412 ) ) ) ) *
                 ( 1 + ( -4.6 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            t2 = ( 0.31 / ( 1 - ( t / ( 5.829 * 5.829 ) ) ) ) *
                 ( 1 + ( -3.2 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
            t3 = ( 0.22 / ( 1 - ( t / ( 5.829 * 5.829 ) ) ) ) *
                 ( 1 +
                   ( -10.3 ) * ( z - z0 + 0.5 * ( ( z * z ) - ( z0 * z0 ) ) ) );
        }
    } else if ( daught == EvtPDL::getId( std::string( "rho+" ) ) ||
                daught == EvtPDL::getId( std::string( "rho-" ) ) ||
                daught == EvtPDL::getId( std::string( "rho0" ) ) ) {
        if ( model == 1 ) {
            // B --> rho form factors
            a1 = 0.261 / ( 1. - 0.29 * shat - 0.415 * shat * shat );
            a2 = 0.223 / ( 1. - 0.93 * shat - 0.092 * shat * shat );
            a0 = 0.372 / ( 1. - 1.40 * shat + 0.437 * shat * shat );
            v = 0.338 / ( 1. - 1.37 * shat + 0.315 * shat * shat );
            t1 = 0.285 / ( 1. - 1.41 * shat + 0.361 * shat * shat );
            t2 = 0.285 / ( 1. - 0.28 * shat - 0.500 * shat * shat );
            t3 = 0.202 / ( 1. - 1.06 * shat - 0.076 * shat * shat );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 (mb = 4.8)
            a1 = 0.240 / ( 1. - ( t / 37.51 ) );
            a2 = ( 0.009 / ( 1. - ( t / 40.82 ) ) ) +
                 ( 0.212 / ( 1. - ( t / 40.82 ) ) / ( 1. - ( t / 40.82 ) ) );
            a0 = ( 1.527 / ( 1. - ( t / ( 5.28 * 5.28 ) ) ) ) +
                 ( -1.220 / ( 1. - ( t / 33.36 ) ) );
            v = ( 1.045 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                ( -0.721 / ( 1. - ( t / 38.34 ) ) );
            t1 = ( 0.897 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -0.629 / ( 1 - ( t / 38.04 ) ) );
            t2 = 0.268 /
                 ( 1. - ( t / 38.59 ) );    // 0.267 caused pole in T3 for q2 -> 0. 0.268 has correct behaviour
            double t3tilde = ( 0.022 / ( 1. - ( t / 40.88 ) ) ) +
                             ( 0.246 / ( 1. - ( t / 40.88 ) ) /
                               ( 1. - ( t / 40.88 ) ) );
            t3 = 0.0;
            if ( fabs( t ) > 1e-10 ) {
                t3 = ( m * m - md * md ) * ( t3tilde - t2 ) / t;
            }
        }
    } else if ( daught == EvtPDL::getId( std::string( "omega" ) ) ) {
        if ( model == 1 ) {
            // B --> rho form factors
            a1 = 0.261 / ( 1. - 0.29 * shat - 0.415 * shat * shat );
            a2 = 0.223 / ( 1. - 0.93 * shat - 0.092 * shat * shat );
            a0 = 0.372 / ( 1. - 1.40 * shat + 0.437 * shat * shat );
            v = 0.338 / ( 1. - 1.37 * shat + 0.315 * shat * shat );
            t1 = 0.285 / ( 1. - 1.41 * shat + 0.361 * shat * shat );
            t2 = 0.285 / ( 1. - 0.28 * shat - 0.500 * shat * shat );
            t3 = 0.202 / ( 1. - 1.06 * shat - 0.076 * shat * shat );
        }
        if ( model == 6 ) {
            // Ball-Zwicky LCSR '05 (mb = 4.8)
            a1 = -0.217 / ( 1. - ( t / 37.01 ) );
            a2 = ( 0.006 / ( 1. - ( t / 41.24 ) ) ) +
                 ( 0.192 / ( 1. - ( t / 41.24 ) ) / ( 1. - ( t / 41.24 ) ) );
            a0 = ( 1.321 / ( 1. - ( t / ( 5.28 * 5.28 ) ) ) ) +
                 ( -1.040 / ( 1. - ( t / 34.47 ) ) );
            v = ( 1.006 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                ( -0.713 / ( 1. - ( t / 37.45 ) ) );
            t1 = ( 0.865 / ( 1. - ( t / ( 5.32 * 5.32 ) ) ) ) +
                 ( -0.622 / ( 1 - ( t / 37.19 ) ) );
            t2 = 0.243 /
                 ( 1. - ( t / 37.95 ) );    // 0.242 caused pole in T3 for q2 -> 0. 0.243 has correct behaviour
            double t3tilde = ( 0.023 / ( 1. - ( t / 40.87 ) ) ) +
                             ( 0.220 / ( 1. - ( t / 40.87 ) ) /
                               ( 1. - ( t / 40.87 ) ) );
            t3 = 0.0;
            if ( fabs( t ) > 1e-10 ) {
                t3 = ( m * m - md * md ) * ( t3tilde - t2 ) / t;
            }
        }
    }
}