2004/01/31 by Signe Seidelin, S. Seidelin, Rodolphe Hoppeler +9 · 2 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Atomic physics #Cold Atom Physics and Bose-Einstein Condensates #Condensation #Elastic scattering #Helium #Inelastic scattering #Ion #Ionization #Metastability #Optics #Physics #Quantum #Quantum, superfluid, helium dynamics #Scattering #Ultracold atom #cond-mat.other
paper · pdf · doi:10.1103/physrevlett.93.090409
published as Physical Review Letters 93 (2004) 090409
openalex publication_date 2004/08/27 · arxiv created 2004/08/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report an experiment measuring simultaneously the temperature and the flux of ions produced by a cloud of triplet metastable helium atoms at the Bose-Einstein critical temperature. The onset of condensation is revealed by a sharp increase of the ion flux during evaporative cooling. Combining our measurements with previous measurements of ionization in a pure Bose-Einstein condensate, we extract an improved value of the scattering length a=11.3(+2.5)(-1.0) nm. The analysis includes corrections that take into account the effect of atomic interactions on the critical temperature, and thus an independent measurement of the scattering length would allow a new test of these calculations.