中国物理学会高能物理分会第十届全国会员代表大会暨学术年会

A new way of Analytic approximation for four flavor neutrino oscillation with matter effect

Not scheduled

20m

Speaker

Mr Baobiao Yue (SYSU in China)

Description

We provide a series of expansion formulas for 3+1 scheme neutrino oscillation probabilities in matter with a constant density. We use a new approach named the Jacobi-like method, which can diagonalize a complex Hermitian Hamiltonian matrix to handle matter effects for four-flavor neutrino oscillation with high precision. This work can be applied to current or proposed accelerator neutrino experiments such as DUNE, NO$\nu$A, T2HK, T2HKK when neutrino mass $m_4 \gg m_k(k=1,2,3)$. We present the performance of the new method on different oscillation channels with similar mixing matrix form to the vacuum case. Furthermore, neutrino oscillation probability functions we studied are greatly simplified with three levels of accuracy. We argue that the effective mixing caused by matter effects between active neutrinos and sterile neutrinos changes more slightly than that among $\nu_e$, $\nu_\mu$ and $\nu_\tau$ when $m_4 \gg m_k(k=1,2,3)$.

Summary

Our analytical approximation formulas have high accuracy with a good simplicity. This result can been applied in lots of experiments such as T2HK, T2HKK, NU$\nu$A and DUNE. We find that the effective $\theta_{12}$ and $\delta_{12}$ can be affected firstly by matter effects and the effective $\theta_{13}$ and $\delta_{13}$ are the second ones. It is remarkable that the effective mixing between active neutrinos and sterile neutrinos changes more slightly than active mixing when $m_4 \gg m_k(k=1,2,3)$.