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This content will become publicly available on June 14, 2023

Title: Uniform modelling of the stellar density of thirteen tidal streams within the Galactic halo
ABSTRACT We present the results of fitting a flexible stellar stream density model to a collection of thirteen streams around the Milky Way, using photometric data from DES, DECaLS, and Pan-STARRS. We construct density maps for each stream and characterize their tracks on the sky, width, and distance modulus curves along the length of each stream. We use these measurements to compute lengths and total luminosities of streams and identify substructures. Several streams show prominent substructures, such as stream broadening, gaps, large deviations of stream tracks, and sharp changes in stream densities. Examining the group of streams as a population, as expected we find that streams with globular cluster progenitors are typically narrower than those with dwarf galaxy progenitors, with streams around 100 pc wide showing overlap between the two populations. We also note the average luminosity of globular cluster streams is significantly lower than the typical luminosity of intact globular clusters. The likely explanation is that observed globular cluster streams preferentially come from lower luminosity and lower density clusters. The stream measurements done in a uniform manner presented here will be helpful for more detailed stream studies such as identifying candidate stream members for spectroscopic follow up and stellar stream more » dynamical modelling. « less
Authors:
; ;
Award ID(s):
1813881
Publication Date:
NSF-PAR ID:
10339972
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
514
Issue:
2
Page Range or eLocation-ID:
1757 to 1781
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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