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Title: Laser trapping of 21Na atoms

This thesis describes an experiment in which about four thousand radioactive 21Na (t1/2 = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped 21Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of 21Na → 21Ne + β+ + ve, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, 21Na atoms were produced by bombarding 24Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The 21Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed bymore » applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.« less
Authors:
 [1]
  1. Univ. of California, Berkeley, CA (United States)
Publication Date:
OSTI Identifier:
10192473
Report Number(s):
LBL--36120
ON: DE95002354; TRN: 94:022845
DOE Contract Number:
AC03-76SF00098
Resource Type:
Thesis/Dissertation
Resource Relation:
Other Information: TH: Thesis (Ph.D.); PBD: Sep 1994
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; SODIUM 21; TRAPPING; BETA DECAY; MAGNETO-OPTICAL EFFECTS; TRAPS; LASER RADIATION; RADIOACTIVE ION BEAMS; PROTON REACTIONS; MAGNESIUM 24 TARGET 661200; 663210; 663530; TECHNIQUES OF GENERAL USE IN PHYSICS; GROUND-STATE RADIOACTIVITY; A = 20-38