Structure:

Down Quark
Charm Anti-quark
Proton

Characteristics:

D-meson (which contains a down quark and a charm antiquark) and a proton, or their antiparticles.

See Also

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Etheric Elements
Meson
Particles and Corpuscles
Table of Quantum Particles
Chapter 6 - The True Nature of Electricity and Gravitation - I, page 129