The Detection of Dark Matter

First off, what exactly is dark matter? It certainly sounds like something that belongs in a sci-fi movie, but what if I told you that it actually exists?

---

Written By: Suhani Garg

December 22, 2022

Figure 1: Dark matter wrapped around distant galaxies

As it turns out, galaxies in our universe spin much faster than they should in comparison to their observable masses. Astronomer Fritz Zwicky first came up with the theory of dark matter as a solution to this problem, which was later confirmed by Vera Rubin, a US astronomer. The theory suggests that the reason galaxies rotate at faster speeds is because there is an unknown type of matter that lies in many of these galaxies. Regular matter (or baryonic matter) is visible through its absorption of radiation. However dark matter doesn’t often interact with baryonic matter and is nearly invisible to light, making it very difficult to detect. But as new technologies emerge, new ways of detection are being implemented. The most common being annihilation and scattering. Annihilation is a method of indirect detection, which is based off the theory that the crash of two dark matter particles results in their annihilation. This produces gamma rays that can be detected using the Fermi telescope. Scattering is a method of direct detection in which dark matter particles scatter off other particles, producing signals that can be detected. One specific signal that many scientists search for is the light produced when a dark matter particle scatters off a xenon atom. Though dark matter remains a mysterious topic, the development of technologies and particle physics points to a deeper understanding of dark matter and the make-up of our universe.

---

Works Cited:

-https://particleastro.brown.edu/dark-matter/ https://www.nasa.gov/audience/forstudents/9-12/features/what-is-dark-matter.html https://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy#:~:text=Second%2C%20it%20is%20not%20in,of%20radiation%20passing%20through%20them https://www.insidescience.org/news/there-something-special-about-our-galaxys-dark-matter

-https://physics.aps.org/articles/v15/117