Globular Cluster Streams as Galactic High-Precision Scales

TL;DR

Globular cluster streams, especially Palomar 5, serve as precise tools for measuring the Milky Way's gravitational potential by modeling their structure and dynamics, offering high-precision galactic scales.

Contribution

This paper demonstrates how modeling globular cluster streams can simultaneously determine cluster properties, orbital motion, and the Galactic gravitational potential.

Findings

Globular cluster streams are effective tracers of the Galactic potential.

Modeling Palomar 5 provides insights into the Milky Way's gravitational field.

Streams enable high-precision measurements of galactic parameters.

Abstract

Tidal streams of globular clusters are ideal tracers of the Galactic gravitational potential. Compared to the few known, complex and diffuse dwarf-galaxy streams, they are kinematically cold, have thin morphologies and are abundant in the halo of the Milky Way. Their coldness and thinness in combination with potential epicyclic substructure in the vicinity of the stream progenitor turns them into high-precision scales. With the example of Palomar 5, we demonstrate how modeling of a globular cluster stream allows us to simultaneously measure the properties of the disrupting globular cluster, its orbital motion, and the gravitational potential of the Milky Way.