5 papers
New Bounds on Heavy QCD Axions from Big Bang Nucleosynthesis
Tae Hyun Jung, Takemichi Okui, Kohsaku Tobioka +1
We study Big Bang Nucleosynthesis (BBN) constraints on heavy QCD axions. BBN offers a powerful probe of new physics that modifies the neutron-to-proton ratio during the process, th…
Excluding MeV-scale QCD axions by at KTeV
Takaya Iwai, Ryosuke Sato, Kohsaku Tobioka +1
An interesting proposal suggests that a QCD axion coupling to the up quark, down quark, and electron remains viable for an axion mass near 10~MeV. In this paper, this possibi…
Irreducible Bhabha background in the detection of muonium-antimuonium conversion
Mitrajyoti Ghosh, Kevin Liguori, Takemichi Okui +1
Experiments such as MACS and the proposed MACE study muonium-antimuonium conversion by the energies of the final-state . The and from an antimuonium decay tend t…
Neutrino properties from muonium-antimuonium mixing
Mitrajyoti Ghosh, Kevin Liguori, Takemichi Okui +1
The nature of neutrino mass -- whether neutrinos are Dirac or Majorana particles -- remains one of the central open questions in particle physics. While observation of neutrinoless…
High Energy Vector Boson Scattering in Four-Body Final States to Probe Higgs Cubic, Quartic, and HEFT interactions
Shameran Mahmud, Kohsaku Tobioka
We compute the energy scales of perturbative unitarity violation in various vector boson scattering (VBS) processes and compare them to lower multiplicity processes. The…