Researcher ORCID Identifier


Graduation Year


Document Type

Campus Only Senior Thesis

Degree Name

Bachelor of Arts


W.M. Keck Science Department

Reader 1

Peter Timbie

Reader 2

Janet Sheung

Rights Information

© 2024 Nadia Marie Schwartz Bolef


The 21-cm line is the electromagnetic radiation spectral line created by the change in energy state of neutral hydrogen atoms. This signal can be used for intensity mapping, a method of mapping the large-scale structure of the universe at different redshifts. However, challenges are being faced in the designing and building of the radio antenna arrays used to detect the 21-cm line signal. Currently, cross-coupling between antenna feeds is introducing beam errors and correlated noise that could overpower the signal. One possible solution we are working on is to use a phased array of antenna feeds instead of dishes and introduce absorptive or reflective collars between antennas. To implement these changes, we have been building scaled models of the antenna feeds, running simulations of these models, and designing and prototyping collars for the feeds. Promising initial results show less cross-coupling between antennas in a two-element array when collars are added. Future work will expand our tests to larger element arrays.

This work was supported by the National Science Foundation's REU program in Astrophysics through NSF award AST-2150222.

This thesis is restricted to the Claremont Colleges current faculty, students, and staff.