Atomic beam magnetic resonance apparatus for systematic measurement of hyperfine structure anomalies (Bohr-Weisskopf effect)

Precision hfs of 126Cs() by ABMR

“…This alternative method, used in [1], looked also very promising: however, the existence of a background, due to laser stray light at the same wavelength as the fluorescence, does not permit the detection of the signal in the case of a very weak atomic beam.…”

“…The apparatus described in [1] includes the triple rf loop magnetic resonance setup for direct g I measurement; for the purpose of this experiment only the C loop was used. Modifications for the on-line work with radioactive isotopes include a first hexapole focussing magnet and an auxiliary ion beam source for off-line extended testing: they are described in [9].…”

“…Precision measurements of the hfs represent a first important and necessary step in determining BW and its systematic study in an isotopic chain. The principles of the measurements were also described as were successful hfs and g-value experiments on stable K and Rb [1]. The apparatus is an evolution from our earlier hfs work on radioisotopes that combined ABMR with laser optical pumping [2].…”

“…We have described previously [1] the atomic beam magnetic resonance (ABMR) apparatus to measure each to an accuracy of 10 −5 or better. Precision measurements of the hfs represent a first important and necessary step in determining BW and its systematic study in an isotopic chain.…”

“…The apparatus [1] was moved to CERN for work with short-lived radioactive cesium isotopes "on-line" produced with use of the PSB (proton-synchrotron booster) -ISOLDE mass separator. We encountered unexpected production problems: First, ISOLDE furnishes 60-keV ion beams.…”