Positronium oscillations to Mirror World revisited

TL;DR

This paper revisits calculations of orthopositronium decay into invisible modes within Mirror World models, refining formulas, incorporating new effects, and providing a computational tool for experimental analysis.

Contribution

It offers corrected and expanded formulas for positronium oscillations, including effects of external fields and collisions, and provides a versatile computational code for experimental predictions.

Findings

Refined calculations of positronium oscillation probabilities.

Inclusion of external field and collision effects in the model.

Application to a planned AEgIS experiment setup.

Abstract

We present a calculation of the branching ratio of orthopositronium decay into an invisible mode, which is done in the context of Mirror World models, where ordinary positronium can disappear from our world due to oscillation into its mirror twin. In this revision we clarify some formulas and approximations used previously, correct them at some places, add new effects relevant for a feasible experiment and finally perform a combined analysis. We include into consideration various effects due to external magnetic and electric fields, collisions with cavity walls and scattering off gas atoms in the cavity. Oscillations of the Rydberg positroniums are also considered. To perform a numerical estimates in a realistic case we wrote computer code, which can be adopted in any experimental setup. Its work is illustrated with an example of a planned positronium experiment within the AEgIS project.