Fix PVZ for pGas+pp: Gaussian distribution(pp) + flat distribution(pGas)

Issue

@samarian noticed that the MC for 2023 pAr+pp alaSMOG has a problem in PVZ distribution. From data tomography, it is clear that the PVZ for BeamGas+BeamBeam alaSMOG should be a Gaussian distribution for pp and a flat Z diftribution for pGas : MC BKK path: /MC/Dev/ppAr-Beam6800GeV-expected-2023-VeloClosed10mm-MagDown-andSMOG1-Nu1.4andNu0.37-Pythia8andEPOS/Sim10b/Digi16/30000000/DIGI

Solution:

I would suggest to remove Generation from the algName in this line. This will call BeamSpotSmearVertex function to smear the pp interaction point with Gaussian distribution.

Generation.BeamSpotSm...   INFO Smearing of interaction point with Gaussian distribution

Otherwise, Generation will call FlatZSmearVertex to flat all PVZ range.

Below is the comparasion:

Edited Jul 17, 2023 by Qiuchan Lu