[clas12_rgk] CVT occupancy from RGK lumi scan

[Yuri Gotra]

Dear Annalisa,

The CVT hit occupancy vs. beam current is shown in this plot:

https://logbooks.jlab.org/files/2023/12/4234980/cvt-occupancy-lumi-rgk.png

Extrapolating this linear dependence the expected CVT occupancies on LH2 
at 150 nA during the streaming readout test is comparable with the one 
on LD2 measured in RGD lumi scan at 100 nA, run 18326. The data rates 
will be similar.

SVT L1 occupancy at 150 nA is also comparable with the one in RGD 
production runs on CuSn target at 100 nA. BMT one will be higher though.

The limiting factors for the CD during the planned streaming readout 
test at 150 nA will be CTOF trigger rate 
(https://logbooks.jlab.org/entry/4194230), BMT data rate which could 
affect the livetime, and CVT performance at high trigger rate.