Rivet
1.8.0
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Get the position of the primary vertex of an event. More...
#include <PVertex.hh>
Public Member Functions | |
const Vector3 | position () const |
Get the primary vertex position. | |
Standard constructors and destructors. | |
PVertex () | |
The default constructor. | |
virtual const Projection * | clone () const |
Clone on the heap. | |
Protected Member Functions | |
void | project (const Event &e) |
Do the projection. | |
int | compare (const Projection &UNUSED(p)) const |
Compare projections. |
Get the position of the primary vertex of an event.
HepMC doesn't reliably return the signal process vertex, so we have to use the "decay vertex" of the beam particles. This gives the right position, within experimental resolution, but ISR effects can mean that the actual vertex is not right. Hence, we don't expose the HepMC GenVertex directly - if it were available, people might try to e.g. look at the of the vertex children, which would be extremely unreliable.