Audio / Video

Ultrasensitive searches for the axion

  • 01:03:07


After four decades, the axion, a hypothetical elementary particle, still represents the best solution to the Strong-CP problem, i.e. why the neutron has a vanishingly small electric dipole moment. Should the axion exist, it would be extremely light, and possess extraordinarily feeble couplings to matter and radiation, far beyond the reach of conventional particle physics experiments. Very light axions would also have been produced abundantly during the Big Bang, and thus the axion represents a well-motivated dark matter candidate. However, the coherent mixing of axions and photons in a strong magnetic field provides a strategy for elegant and ultrasensitive experiments that may finally render the axion observable. This talk will primarily review the microwave cavity search for halo dark matter axions and present first results from a high-frequency search, but also briefly discuss the search for solar axions, and purely laboratory experiments, such as photon regeneration (“shining light through the wall”).



Ultrasensitive searches for the axion


University of California, Berkeley. Dept. of Physics


Berkeley, CA, University of California, Berkeley, Dept. of Physics, November 28, 2016

Full Collection Name

Physics Colloquia






1 streaming video file

Other Physical Details

digital, sd., col.


Physics Library


Recorded at a colloquium held on November 28, 2016, sponsored by the Dept. of Physics, University of California, Berkeley.

originally produced as an .mts file in 2016

Speakers: van Bibber, Karl.

Usage Statement

Researchers may make free and open use of the UC Berkeley Library’s digitized public domain materials. However, some materials in our online collections may be protected by U.S. copyright law (Title 17, U.S.C.). Use or reproduction of materials protected by copyright beyond that allowed by fair use (Title 17, U.S.C. § 107) requires permission from the copyright owners. The use or reproduction of some materials may also be restricted by terms of University of California gift or purchase agreements, privacy and publicity rights, or trademark law. Responsibility for determining rights status and permissibility of any use or reproduction rests exclusively with the researcher. To learn more or make inquiries, please see our permissions policies (


Physics Colloquia


colloquia/11-28-16vanBibber.mp4 01:03:07

Linked Resources

View record in Digital Collections.