2021/04/30 by Carolina Arbeláez, Claudio Dib, Kevin Monsálvez-Pozo +1 · 1 citation
Physics and Astronomy · #hep-ph #hep-ex
paper · pdf · doi:10.1007/jhep07(2021)154
This submission matches the published version. 23 pages, 4 figures
arxiv created 2021/07/26 · arxiv updated 2021/07/27
We implement a minimal linear seesaw model (LSM) for addressing the Quasi-Dirac (QD) behaviour of heavy neutrinos, focusing on the mass regime of MN \lesssim MW. Here we show that for relatively low neutrino masses, covering the few GeV range, the same-sign to opposite-sign dilepton ratio, Rℓ ℓ, can be anywhere between 0 and 1, thus signaling a Quasi-Dirac regime. Particular values of Rℓ ℓ are controlled by the width of the QD neutrino and its mass splitting, the latter being equal to the light-neutrino mass mν in the LSM scenario. The current upper bound on m_ν1 together with the projected sensitivities of current and future |UN ℓ|2 experimental measurements, set stringent constraints on our low-scale QD mass regime. Some experimental prospects of testing the model by LHC displaced vertex searches are also discussed.