cross section calculation

Manojg

Hi everybody,

I have a experimental question. In cross-section calculation of production of particles (say D), one counts the number of produced D. To selection the D one has to apply some kinematic cuts. If cuts are tight, number of D will be less and if cuts are loose, number of D will be large. So, cuts is going to effect the calculated cross-section. How these effect is taken into account?

Thanks.

ParticleGrl

Generally, what is actually calculated is a differential cross-section. This is then integrated numerically in the allowed phase space region- the cuts come in as boundaries of allowed phase space.

Manojg

Ok, thanks for reply.

My question is when you are analyzing the real data. You see a peak of a particle D, you select that particle by taking cuts around its peak, and count the number of events giving that particle. To calculate the cross-section, you divide the number of D particle by flux. Now, the number of D particle depend on the cut around the peak. How do take care of effect due to different cuts? Does not the cross-section depends on the cut you are taking to select D particle?