The interferometric baselines and GRAVITY astrometric error budget

TL;DR

This paper discusses the error budget of the GRAVITY instrument, focusing on baseline-induced errors, to achieve microarcsecond astrometric precision for VLTI observations.

Contribution

It provides an analysis of interferometric baseline errors as part of the comprehensive error budget for the GRAVITY instrument.

Findings

Baseline errors significantly impact astrometric accuracy

Error mitigation strategies are essential for microarcsecond precision

The study informs the design and calibration of high-precision interferometers

Abstract

GRAVITY is a new generation beam combination instrument for the VLTI. Its goal is to achieve microarsecond astrometric accuracy between objects separated by a few arcsec. This $10^6$ accuracy on astrometric measurements is the most important challenge of the instrument, and careful error budget have been paramount during the technical design of the instrument. In this poster, we will focus on baselines induced errors, which is part of a larger error budget.