include/EvtGenBase/EvtBlattWeisskopf.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVT_BLATT_WEISSKOPF_HH
0022 #define EVT_BLATT_WEISSKOPF_HH
0023
0024 // Blatt-Weisskopf penetration form factor for a resonance R->AB.
0025 // Taken from CLEO preprint 00-23 (hep-ex/0011065)
0026
0027 class EvtBlattWeisskopf {
0028   public:
0029     EvtBlattWeisskopf( int LL, double R, double p0 );
0030     EvtBlattWeisskopf( const EvtBlattWeisskopf& );
0031
0032     double operator()( double p ) const;
0033
0034   private:
0035     int _LL;           // angular momentum of daughters
0036     double _radial;    // resonance radial parameter
0037     double _p0;
0038
0039     double _F0;    // formula evaluated at _p0
0040     double compute( double p ) const;
0041 };
0042
0043 #endif