BZ and neutrino physics
In Science, there is another use for the abbreviation "BZ", namely in neutrino physics.
V. S. Berezinsky and G. T. Zatsepin published their landmark article 'Cosmic rays at ultra high energies (neutrino?)' in 1969 [Beresinsky, V. S. and Zatsepin, G. T. (1969) Phys. Lett. B, 28(6):423-424 (DOI)].
K. I. Greisen [Greisen, K. I. (1966). Phys. Rev. Lett., 16(17):748-750 (DOI)] and G. T. Zatsepin and V. A. Kuzmin [Zatsepin, G. T. and Kuzmin, V. A (1966) JETP Lett., 4(3):78-80 (link)] had already suggested in 1966 that cosmic rays - in particular protons - would be destroyed by interactions with the cosmic microwave background, which is called the GZK process. This destruction would either produce charged pions and neutrons or neutral pions and protons. Later, V. S. Beresinsky and G. T. Zatsepin asserted that the destruction of the pions and neutrons would produce a measurable neutrino ux. For example, a charged pion, say the pi+, overwhelmingly decays to an anti-muon and a muon-neutrino. The anti-muon can then further decay into a muon-anti-neutrino, a positron, and an electron-neutrino. The neutron can also beta decay into a proton, electron, and electron-anti-neutrino, (but this is not the leading contribution to the flux at these energies.). Therefore, if you take the pions and neutrons from the GZK process, you can produce a ux of neutrinos that should be measurable.And because the GZK cutoff is an experimentally confirmed phenomenon, then we should see these associated BZ neutrinos. Most of the literature would call this the "GZK neutrino flux" but there is a movement in the field to give BZ credit where it's due - because it was V. S. Berezinsky and G. T. Zatsepin that suggested the neutrino production, not GZK.
Some more information can be found in this book chapter.