PScatterCrossSection::PScatterCrossSection(const Char_t *id, const Char_t *de) :
    PAngularDistribution(id, de) {

    beam = target = NULL;
    pf2  = NULL;
    qmax = 0.0;
    qmin = -1;
    npx = npy = -1;

    TF1 * dummy = new TF1("dummy","1",-1,1);
    SetAngleFunction(dummy);
 
} ;