The muonic hydrogen lamb shift experiment at PSI

Kottmann, F. ; Amir, W. ; Biraben, F. ; Conde, C. A. N. ; Dhawan, S. ; Hansch, T. W. ; Hartmann, F. J. ; Hughes, V. W. ; Huot, O. ; Indelicato, P. ; et, al. (2001) The muonic hydrogen lamb shift experiment at PSI Hyperfine Interactions, 138 (1-4). pp. 55-60. ISSN 0304-3843

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A measurement of the 2S Lamb shift in muonic hydrogen (μ-p) is being prepared at the Paul Scherrer Institute (PSI). The goal of the experiment is to measure the energy difference ΔE(25 P 3/2-23 S ½) by laser spectroscopy (λ≈6μm) to a precision of 30 ppm and to deduce the root mean square (rms) proton charge radius with 10-3 relative accuracy, 20 times more precise than presently known. An important prerequisite to this experiment is the availability of long-lived μp2S -atoms. A 2S-lifetime of ~1 μs - sufficiently long to perform the laser experiment - at H2 gas pressures of 1-2 hPa was deduced from recent measurements of the collisional 2S-quenching rate. A new low-energy negative muon beam yields an order of magnitude more muon stops in a small low-density gas volume than a conventional cloud muon beam. A stack of ultra-thin carbon foils is the key element of a fast detector for keV-muons. The development of a 2 keV X-ray detector and a 3-stage laser system providing 0.5 mJ laser pulses at 6 μm is on the way.

Item Type:Article
Source:Copyright of this article belongs to Springer-Verlag.
ID Code:26883
Deposited On:08 Dec 2010 13:02
Last Modified:17 May 2016 10:10

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