title: Recombination fluorescence in ultracold neutral plasmas.
abstract: We present the first measurements and simulations of recombination fluorescence from ultracold neutral calcium plasmas. This method probes three-body recombination at times less than 1 micros, shorter than previously published time scales. For the lowest initial electron temperatures, the recombination rate scales with the density as n0(2.2), significantly slower than the predicted n0(3). Recombination fluorescence opens a new diagnostic window in ultracold plasmas. In most cases it probes deeply bound level populations that depend critically on electron energetics. However, a perturbation in the calcium 4snd Rydberg series allows our fluorescence measurements to probe the population in weakly bound levels that result just after recombination.
authors.affiliation: Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.
authors.forename: S D
authors.initials: SD
authors.lastname: Bergeson
authors.forename: F
authors.initials: F
authors.lastname: Robicheaux