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Penning collisions of laser-cooled metastable helium atoms

F. Pereira Dos Santos·F. Perales·J. Leonard·A. Sinatra·Junmin Wang·F. S. Pavone·E. Rasel·C. S. Unnikrishnan·M. Leduc
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Abstract

We present experimental results on the two-body loss rates in a magneto-optical trap of metastable helium atoms. Absolute rates are measured in a systematic way for several laser detunings ranging from -5 to -30 MHz and at different intensities, by monitoring the decay of the trap fluorescence. The dependence of the two-body loss rate coefficient $β$ on the excited state ($2^3P_2$) and metastable state ($2^3S_1$) populations is also investigated. From these results we infer a rather uniform rate constant $K_{sp}=(1{\pm}0.4)\times10^{-7}$ cm$^3$/s.

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F. Pereira Dos Santos, F. Perales, J. Leonard, A. Sinatra, Junmin Wang, F. S. Pavone, E. Rasel, C. S. Unnikrishnan, M. Leduc. 2001-03-20. Penning collisions of laser-cooled metastable helium atoms. https://doi.org/10.1007/s100530170228

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