English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In this paper, we evaluate the (second) lightest mass $M_{1,2}$ ofright-handed neutrino $\nu_{R1,2}$ in grand unified theories with the type-Iseesaw mechanism that predicts an almost massless neutrino $m_{1 \, \rm or \,3} \sim 0$. By chiral perturbative treatment, the masses $M_{1,2}$ areexpressed as $M_{1} = m_{D1}^{2}/m_{11} , \, M_{2} = m_{D2}^{2} m_{11} /(m_{11} m_{22} - m_{12}^{2})$ with the mass matrix of left-handed neutrinos $m$in the diagonal basis of the Dirac mass matrix $m_{D}$.  Assuming $m_{Di}$ and the unitary matrix $V$ in the singular valuedecomposition $(m_{D})_{ij} = V_{ik} m_{D k} U^{\dagger}_{kj}$ are close toobserved fermion masses and the CKM matrix, $M_{1,2}$ and their allowed regionsare expressed by parameters in the low energy and unknown phases. As a result,for $m_{D1} \simeq 0.5$ MeV and $m_{D2} \simeq 100$ MeV, we obtain $M_{1}^{\rmNH} \simeq 3 \times 10^{4 - 6}$ GeV and $M_{2}^{\rm NH} \simeq 3 \times10^{6-8}$ GeV in the NH, $M_{1}^{\rm IH} \simeq 5 \times 10^{3 - 4}$ GeV and$M_{2}^{\rm IH} \simeq 4 \times 10^{8-9}$ GeV in the IH. These upper and lowerbounds are proportional to $m_{Di}^{2}$ or $m_{D1} m_{D2}$.

Chiral perturbative evaluation for the (second) lightest mass $M_{1,2}$  of right-handed neutrino $\nu_{R 1,2}$ in unified theories with sequential  dominance