How to see B0 meson


I would like to check how many B0 mesons are created in my setup, but I cannot see the B0 meson.
The setup is:
Physics list: QGSP_BERT
Beam: proton 120 (500) GeV
Target: Graphite
and check if there is B0 meson (pdgid: 511) in the graphite target.
C.O.M energy would be > 10 GeV which should be enough to create B0 meson.
Does someone have any idea about this?
If more information is needed, please let me know.

Best Regards,

Could someone have any idea about this?