Claire Williams

Claire is standing in front of a park with palm trees. In the background you can see the San Francisco skyline. She is wearing a black shirt and a vest.


Graduate student in the Astronomy and Astrophysics
Division of the UCLA Department of Physics and Astronomy studying theoretical astrophysics.

Stellar collisions at high redshift

We developed an analytic framework to understand how stellar collisions may shape high redshift systems.

The nature of star clusters at cosmic dawn

We investigate the nature of the first star clusters in the universe using cosmological simulations, comparing to results from the James Webb Space Telescope.

JWST may reveal faint galaxies formed through supersonic streams of dark matter

Click below to read a description of our study that investigates how the James Webb Space Telescope may reveal the previously undetected supersonic motions of our early Universe. To read the published Letter in the Astrophysical Journal, click here.

Formation of dwarf galaxies and other research

In regions of the universe with a highly supersonic stream velocity, halos dominated by dark matter form with spatially-offset baryonic components. These may be the progenitors of some ultra faint galaxies. Read more about this and other projects below:

Publications

My research publications and academic work can be found here:

A cosmological framework for stellar collisions at high redshift in proto-globular clusters, nuclear star clusters, and Little Red Dots

C. E. Williams, S. Naoz, S. C. Rose, B. Burkhart, N. Yoshida, A. Chen, K. Kremer, W. Lake, F. Marinacci, S. H. Menon, M. Vogelsberger

Submitted to ApJ.

Observing compact Pop III star clusters and the presence of cosmic streaming

C. E. Williams, S. Naoz, N. Yoshida, W. Lake, B. Burkhart, F. Marinacci, M. Vogelsberger, S. H. Menon, A. Chen, K. Kremer

ApJ 997 202 (2026)  ·  arXiv:2509.22776

Teaching

Teaching and mentorship have been an essential part of my path in astronomy.

Outreach

Now more than ever it is important to broaden inclusion in astronomy and share our understanding of the Universe with the public.

Contact

Please reach out to me at my email. I am available for meetings in-person on the UCLA campus or remotely over zoom.

About Me

Claire posing with a surfboard with blue stripes in front of the ocean. I am a fifth-year graduate student and Ph.D. candidate in Astronomy and Astrophysics at UCLA working in Smadar Naoz's research group. Originally from Portland, OR, I received my Bachelor's degree in physics at Carleton College in Northfield, MN.

In my free time, I love to spend time outdoors, cook and bake at home, and try out LA's restaurants. At UCLA, I am taking full advantage of the beautiful weather and beaches! I'm interested in sustainability and environmental justice, and I can often be found working on handmade garments, either knitting, crocheting, or sewing. I miss my family dogs Percy and Orion and our four sweet kitties who are at home in Portland.