# Practical study of optical stellar interferometry

## TL;DR

This paper demonstrates an observational technique for stellar interferometry, analyzing atmospheric turbulence effects on interference patterns of bright stars, and provides a practical methodology for postgraduate astronomy students.

## Contribution

It introduces a detailed method for analyzing stellar interferograms and measuring atmospheric turbulence effects, including the Fried parameter, for educational purposes.

## Key findings

- Atmospheric turbulence reduces fringe visibility in interferograms.
- Different baselines reveal how visibility decays with distance.
- Method allows estimation of the Fried parameter r0.

## Abstract

In this work we present an observational technique and a detailed analysis of the stellar interferograms produced by three bright stars: Betelgeuse, Rigel and Sirius. It is shown that the atmospheric turbulence is responsible for the reduction of the long-exposure fringe visibility of the obtained interference patterns. By using different baselines in our interferometer, we are able to distinguish the decay of the visibility with the baseline, how different parameters such us the diameter of the holes in our interferometer or their distribution affects the pattern, and to measure the turbulence with the estimation of the Fried parameter r0. The work and methodology are presented as a method for postgraduate students that targets practical learning of optical interferometry in astronomy and how it is affected by several causes, such as the atmospheric turbulence.