Untangling Magellanic Streams

The Magellanic Stream (MS) is known to contain multiple H<small>I</small> strands and corresponding stellar populations are being discovered. Combining a sample of 17 stars from the H3 (“Hectochelle in the Halo at High Resolution”) survey with 891 stars drawn from the <em>Gaia<...

Full description

Saved in:
Bibliographic Details
Main Authors: Dennis Zaritsky, Vedant Chandra, Charlie Conroy, Ana Bonaca, Phillip A. Cargile, Rohan P. Naidu
Format: Article
Language:English
Published: Maynooth Academic Publishing 2025-02-01
Series:The Open Journal of Astrophysics
Online Access:https://doi.org/10.33232/001c.129885
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The Magellanic Stream (MS) is known to contain multiple H<small>I</small> strands and corresponding stellar populations are being discovered. Combining a sample of 17 stars from the H3 (“Hectochelle in the Halo at High Resolution”) survey with 891 stars drawn from the <em>Gaia</em> DR3 catalog, we trace stars along a sub-dominant strand of the MS, as defined by gas content, across 30${\mathstrut}^\circ$ on the sky. We find that the corresponding dominant strand at the similar position along the MS is devoid of stars with Galactocentric distance $\lesssim 55$ kpc while the subdominant strand shows a close correspondence to such stars. We conclude that (1) these two Stream strands have different origins, (2) they are likely only close in projection, (3) the subdominant strand is tidal in origin, and (4) the subdominant strand is composed of "disk" material, gas and stars, with a chemical composition that marginally favors it coming from the Small Magellanic Cloud.
ISSN:2565-6120