Here are the data structures with brief descriptions:

CGparticle	Lightweight particle specification and primary vertex shooter
CGParticleLundReader	Built-in reader for Lund generated-particle files
CGParticleReader	Abstract base class for gparticle file readers
CGParticleRecord	Immutable generated-particle metadata used for output banks
CGparticleRuntimeRecord	Runtime values for one generated primary particle
CGParticleSourceDefinition	One configured `-gparticlefile` source