Dark Matter Accounts for Perturbation in the GD-1 Stellar Stream by Carissma McGee. on Tuesday 29 November

The longest recognized stellar stream in the Milky Way Galaxy has an expanse

of over more than half the north sky. There was a physical disturbance within

the stream, 500 million years ago, which could have been the scar of a dark

matter collision. Due to its proximity to the galactic center, the GD-1 stellar

stream can act as an antenna for gravitational perturbations. In 2018, a

significant gap in GD-1 was discovered due to perturbation. A stream gap occurs

when a massive object collides with the stellar stream. Based on the chasm

location and width, we can guess when and where the impact occurred. Using

globular cluster sky coordinates and simulated galactocentric distributions, we

calculated how close each globular cluster came to the GD-1 stream. This would

be the first time a globular cluster has come close enough to the GD-1 stream

to impact another object. Clusters, on the other hand, rarely approach GD-1,

indicating that it was struck by something more exotic, like a clump of dark

matter, when discovered. A simulation and theoretical model were created to

better understand the GD-1 stellar stream behavior. These details can be used

to map the large-scale distribution of dark matter in our galaxy as well as the

small-scale structure of dark matter in the host galaxies of the streams.

Examination of stellar streams and detection of subhalos will not only confirm

the presence of dark matter but also reveal information about its particle

nature.

arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.14740v1