# From neutrino electromagnetic interactions to spin oscillations in transversal matter currents

## TL;DR

This paper derives an effective Hamiltonian showing that neutrino spin oscillations can be caused by interactions with transversal matter currents, expanding understanding beyond magnetic field effects.

## Contribution

It introduces a new derivation of the neutrino evolution Hamiltonian accounting for transversal matter currents, enabling analysis of spin oscillations in this context.

## Key findings

- Neutrino spin oscillations can be induced by transversal matter currents.
- The derived Hamiltonian applies to various neutrino mass and flavor states.
- This work broadens the mechanisms known to cause neutrino spin oscillations.

## Abstract

Massive neutrinos have nonzero magnetic moments. It is known that the neutrino spin oscillations can be induced by the neutrino magnetic moment interaction with the transversal magnetic field. We perform a regions derivation of the effective neutrino evolution Hamiltonian in moving matter and show that spin oscillations can be engendered by the interaction with the transversal current of matter. The obtained general expression for the neutrino effective evolution Hamiltonian can be used for investigations of various types of neutrino spin oscillations in the transversal matter currents considered in the neutrino mass and flavour basis.