Effects of chaos on the detectability of stellar streams

TL;DR

This paper investigates how chaos in gravitational potentials affects the lifespan and detectability of stellar streams, revealing that chaos shortens their observable existence and depends on data quality.

Contribution

It provides a comparative analysis of stellar streams in chaotic versus non-chaotic regions, highlighting the impact of chaos on stream detectability.

Findings

Chaos reduces the detection time of stellar streams.

Detectability depends on data quality and stellar halo models.

An upper limit to detectable stellar mass is established.

Abstract

Observations show that stellar streams originating in satellite dwarf galaxies are frequent in the Universe. While such events are predicted by theory, it is not clear how many of the streams that are generated are washed out afterwards to the point in which it is imposible to detect them. Here we study how these diffusion times are affected by the fact that typical gravitational potentials of the host galaxies can sustain chaotic orbits. We do this by comparing the behaviour of simulated stellar streams that reside in chaotic or non-chaotic regions of the phase-space. We find that chaos does reduce the time interval in which streams can be detected. By analyzing detectability criteria in configuration and velocity space, we find that the impact of these results on the observations depends on the quality of both the data and the underlying stellar halo model. For all the stellar streams, we obtain a similar upper limit to the detectable mass.