Always spell out the name of the particle – do not use the mathematical symbol in text.
The mathematical symbols may only be used in diagrams when they are spelled out in full in the accompanying caption. See graphs and charts.
Particles with a letter (such as B meson) only take a hyphen when they are used as a compound adjective:
The physicists detected lots of B mesons in the B-meson experiment. Next door, their colleagues at the charm-quark detector were looking for charm quarks.