# Cavity Microwave Searches for Cosmological Axions

- Institution: CERN
- Department: Special Lecture Series
- Speaker: Karl van Bibber
- Year: 2005
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3014289)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Outline of the lecture:

The lecture will cover the searches for dark matter axions based on the microwave cavity experiment of Sikivie. The topics will begin with a brief overview of halo dark matter, and the axion as a candidate. The principle of resonant conversion of axions in an external magnetic field will be described, and practical considerations in optimizing the experiment as a signal-to-noise problem. A major focus of the lecture will be the two complementary strategies for ultra-low noise detection of the microwave photons - the "photon-as-wave" approach (i.e. conventional heterojunction amplifiers and soon quantum-limited SQUID devices), and "photon-as-particle" (i.e. Rydberg-atom single-quantum detection). Experimental results will be presented; these experiments have already reached well into the range of sensitivity to exclude plausible axion models, for limited ranges of mass. The lecture will conclude with a discussion of future plans and challenges for the microwave cavity experiment..

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## Lectures

1. [Cavity Microwave Searches for Cosmological Axions](https://invisiblenetwork.ai/learn/cern/3014289/9fa03cdac1ef), 1 h 39 min (CERN's player)