# The influence of dark matter halo on the stellar stream asymmetry via dynamical friction

## TL;DR

This paper investigates how dynamical friction caused by dark matter halos affects the asymmetry in stellar streams from globular clusters, offering a potential method to probe dark matter distribution.

## Contribution

It introduces a model linking dynamical friction effects to observable stellar stream asymmetries, providing a new approach to constrain dark matter properties.

## Key findings

- Theoretical estimates of star stream asymmetry match the order of magnitude of observations.
- Dynamical friction causes measurable shifts in globular cluster positions and stream star distributions.
- Current observational uncertainties limit precise constraints on dark matter from this method.

## Abstract

We study the effect of dynamical friction on globular clusters and on the stars evaporated from the globular clusters (stellar streams) moving in a galactic halo. Due to dynamical friction, the position of a globular cluster (GC) as a stream progenitor starts to shift with respect to its original position in the reference frame of initial GC orbit. Therefore the stars that have evaporated at different times have different mean position with respect to the GC position. This shifting results in a certain asymmetry in stellar density distribution between the leading and trailing arms of the stream. The degree of the asymmetry depends on the characteristics of the environment in which the GC and the stream stars move. As GCs are located mainly in outer parts of a galaxy, this makes dynamical friction a unique probe to constrain the underlying dark matter spatial density and velocity distributions. For a GC NGC 3201 we compared our theoretical shift estimates with available observations. Due to large uncertainties in current observation data, we can only conclude that the derived estimates have the same order of magnitude.