Beryllium-9 Anomaly

Beryllium-9 is not synthesized in standard BBN — it is produced exclusively by cosmic ray spallation of carbon, nitrogen, and oxygen nuclei in the interstellar medium, and its abundance in old halo stars increases linearly with metallicity as expected for a secondary process. However, measurements of Be abundance in extremely metal-poor halo stars with [Fe/H] < -3 have found beryllium present at levels slightly above the pure spallation prediction, suggesting either a primary production channel active at very early times, or a cosmological production mechanism preceding normal stellar nucleosynthesis. This beryllium floor — the minimum Be abundance below which no further decrease is observed — implies an early-universe source of Be that is not accommodated in standard ΛCDM cosmology.

Successive Collision Theory provides a natural explanation for the beryllium-9 floor through the pre-existing stellar populations and cosmic ray environment inherited from the colliding pockets. The two spacetime pockets that collided to produce our observable universe had undergone prior stellar evolution in the eternal universe, producing cosmic rays through supernova remnant acceleration and active AGN jets across prior cosmological epochs. These pre-existing cosmic rays had processed the CNO nuclei present in the pockets' interstellar media through spallation reactions, producing beryllium-9 that was incorporated into the gas and dust of the collision debris field. When the first post-collision halo stars formed from this pre-enriched debris, they inherited a floor level of Be corresponding to the spallation products of the pre-existing cosmic ray irradiation — not from any exotic BBN-era process but from the straightforward spallation physics operating over the extended pre-collision epoch.

The SCT prediction is that the Be floor should correlate with other pre-existing abundance signatures: the lithium-7 dilution, the metallicity floor from pre-existing stellar populations, and the early JWST galaxy observations all reflect the same pre-collision stellar content of the debris field. Halo stars that formed earliest from the most pristine collision debris will show the highest Be floor relative to their iron abundance, because they sample the pre-collision spallation products most directly before dilution by post-collision stellar nucleosynthesis enrichment. The slope of the Be-versus-metallicity relation at very low [Fe/H] should therefore flatten or show increased scatter compared to the linear spallation trend, reflecting the mixed origin of Be from both pre-collision inheritance and post-collision cosmic ray spallation in the SCT picture.