1998/09/30 by Thomas C. Killian, T. C. Killian, Dale. G. Fried +6 · 11 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Quantum, superfluid, helium dynamics #physics.atom-ph
paper · pdf · doi:10.1103/physrevlett.81.3807
Accepted for publication in PRL, 9 pages, 4 PostScript figures, ReVTeX. Updated connection of our measurement to theoretical work
arxiv created 1998/10/05 · openalex publication_date 1998/11/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
We have observed the cold collision frequency shift of the 1S- 2S transition in trapped spin-polarized atomic hydrogen. We find \ensuremathΔ\ensuremathν_1S\ensuremath-2S\phantom\rule0ex0ex=\phantom\rule0ex0ex\ensuremath-3.8\ifmmode±\else\textpm\fi0.8\ifmmode×\else\texttimes\fi10^\ensuremath-10nHzcm3, where n is the sample density. From this we derive the 1S- 2S s-wave triplet scattering length, a_1S\ensuremath-2S\phantom\rule0ex0ex=\phantom\rule0ex0ex\ensuremath-1.4\ifmmode±\else\textpm\fi0.3nm, which is in fair agreement with a recent calculation. The shift provides a valuable probe of the distribution of densities in a trapped sample.