[Triumf-seminars] TRIUMF Seminar today at 14:00

[postmaster@admin.triumf.ca]

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Date/Time: Thu 2006-05-25 at 14:00

Location:  Auditorium          

Speaker:   Alain Lapierre (UC Berkeley)

Title:     Search for a Temporal Variation of the Fine-Structure Constant alpha by Radio-Frequency Spectroscopy of Atomic Dy

Abstract: Searches for variations of fundamental constants are of basic importance to explore the possibility of new physics beyond Einstein's general relativity and develop an ultimate unified theory of matter, space, and time. In that seminar, I will give an overview of an ongoing search at the University of California at Berkeley for a possible time variation of the fine-structure constant alpha in atomic dysprosium (Dy). After a brief look at the motivations and the results of analyses of recent quasi-stellar object (QSO) absorption spectra indicating an alpha variation of Delta alpha/(alpha Delta t) ~ (7+/-2)x 10^-16 yr^-1, I will discuss the particularity of Dy, and present the experimental method and preliminary results of a search with a current radio-frequency (rf) spectrometer. This spectrometer will ultimately allow us to reach a sensitivity of 10^-15 yr^-1 and rival the best atomic clock measurements. A new rf spectrometer is being built to surpass this sensitivity. I will conclude by quickly presenting the main requirements necessary to reach a sensitivity of an alpha variation of ~10-18 yr-1.

Stimulants available 15 minutes before the talk.

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Subscription information available at http://admin.triumf.ca/netdata/seminars/list


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