2020/08/31 by Alexey Boyarsky, Maksym Ovchynnikov, Oleg Ruchayskiy +1
Physics and Astronomy · #Astronomy #Big Bang nucleosynthesis #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Lepton #Nuclear physics #Nuclear reaction #Nucleosynthesis #Particle physics #Particle physics theoretical and experimental studies #Physics #astro-ph.CO #hep-ph
paper · pdf · doi:10.1103/physrevd.104.023517
published as Phys. Rev. D 104, 023517 (2021) · Journal version
openalex created_date 2020/08/07 · arxiv created 2021/07/13 · openalex publication_date 2021/07/16 · arxiv updated 2021/07/19 · openalex updated_date 2026/08/05
We constrain the lifetime of thermally produced heavy neutral leptons (HNLs) from big bang nucleosynthesis. We show that even a small fraction of mesons present in the primeval plasma leads to the overproduction of primordial helium-4. This constrains the lifetime of HNLs to be \ensuremathτN<0.02 s for masses above the mass of the pion (as compared to 0.1 s reported previously). In combination with accelerator searches, this allows us to put a new lower bound on the HNL masses and define the ``bottom line'' for HNL searches at the future Intensity Frontier experiments.