Search

We have measured the non-resonant photoionization cross section of the [7P.sub.3/2] state of francium for 442 nm light to be 20.8 [+ or -] 7.1 Mb. Atoms were irradiated in a magneto-optical trap, and we deduce the photoionization rate from the change in trap lifetime. The result is consistent with a simple extrapolation of known cross sections for other alkali atoms. Key words: photoionization, alkali atoms, magneto-optical trap. Nous mesurons que la section efficace de photo-ionisation hors resonance de l'etat [7P.sub.3/2]] du francium pour une lumiere de 442 nm est de 20.8 [+ or -] 7.11 Mb. Les atomes sont irradies dans un piege magneto-optique et nous deduisons le taux de photo-ionisation a partir du changement du temps de vie du piege. Le resultat est coherent avec la simple extrapolation de sections efficaces connues pour d'autres atomes alcalins. [Traduit par la Redaction] Mots-cles: photo-ionisation, atome alcalin, piege magneto-optique, francium, etat excite., 1. Introduction The near-threshold photoionization of atoms is an important process to consider as a loss mechanism in two-species magnetooptical traps (MOTs) [1]. It is also of indirect importance in [...]

Abstract: A useful tool that can achieve a high level of spin polarization is a circularly polarized far off-resonance dipole force trap (CFORT). This work is the first step in [...]

Motivated by a search for a new physics beyond the standard model, the MTV experiment (Mott Polarimetry for T-Violation Experiment) is intended to achieve the highest precision test of time-reversal symmetry in polarized nuclear beta decay by measuring a triple correlation (the R-correlation). The first physics run of the MTV experiment was performed in 2010 at TRIUMF-ISAC. This paper gives preliminary results and describes the next generation setup, which involves a cylindrical drift chamber.

Abstract: A measurement of the neutrino asymmetry is presented which represents the first search for new physics using polarized radioactive atoms initially cooled and confined in a magneto-optical trap. Optical pumping and photoionization techniques are used to generate and measure, in situ, a highly spin-polarized sample of the short-lived -emitter 37K. The angular distribution of neutrinos from this polarized decay, inferred from the daughter recoil asymmetry, is used to search for a hypothetical current in the weak interaction. We find the ν asymmetry parameter to be , in agreement with the standard model''s purely interaction. [Copyright &y& Elsevier]