Distinguishing an ejected blob from alternative flare models at the Galactic centre with GRAVITY

TL;DR

This paper evaluates how the upcoming GRAVITY instrument can differentiate between an ejected blob and other flare models at the Galactic centre by simulating observational data.

Contribution

It develops realistic simulations of GRAVITY data to assess its capability in identifying the nature of flares at the Galactic centre.

Findings

GRAVITY can distinguish ejected blobs if inclination >= 45 degrees.

The instrument can identify flare models for brightness mK between 14 and 15.

Detection is feasible for flare durations longer than 1 hour 30 minutes.

Abstract

The black hole at the Galactic centre exhibits regularly flares of radiation, the origin of which is still not understood. In this article, we study the ability of the near-future GRAVITY infrared instrument to constrain the nature of these events. We develop realistic simulations of GRAVITY astrometric data sets for various flare models. We show that the instrument will be able to distinguish an ejected blob from alternative flare models, provided the blob inclination is >= 45deg, the flare brightest magnitude is 14 <= mK <= 15 and the flare duration is >= 1h30.