GG->4leptons process in CalcHep
Dear colleagues
I'd like to ask for your help to understand the following:
I calculated the xsec for two processes in CalchHep 3.8.7, using the model SM(+hgg+h4G): pp -> ZZ and pp->e,E,ne,Ne, with 14 TeV CME and NNPDF pdf. For each subprocess, I compared xsec(qq -> ZZ)*Br(
Many thanks
Question information
- Language:
- English Edit question
- Status:
- Open
- For:
- CalcHEP Edit question
- Assignee:
- No assignee Edit question
- Last query:
- 2021-02-24
- Last reply:
Andre Nepomuceno (asevedo) said : | #1 |
I forgot to mention that the W and photon are excluded from the calculations. Only qq (gg) -> ZZ and qq (gg) -> e,E,ne,Ne via ZZ, are considered.
Andre Nepomuceno (asevedo) said : | #2 |
I verified that, if I apply a cut on M(l,l) and M(n,n) > 60 GeV, the two process agree. It seems there is a divergence in gg->4l process for M(l,l) < 40 GeV, which is not observed in qq->4l. Also, the problem does note appear if no PDF is chosen (PDF OFF), so it must be related to gluon PDF.
Can you help with this problem?
Provide an answer of your own, or ask Andre Nepomuceno for more information if necessary.