Determination of spin, magnetic moment and isotopic shift of neutron rich205Hg by optical pumping

Abstract

Abstract. Neutron rich 2~(T1/2 =5.2 min) was produced and on-line mass separated at the ISOLDE facility at CERN. The polarization achieved by optical pumping via the atomic line (6s 2 ~S 0,--,6s 6p 3P t, 2 = 2 537 A) was monitored by the/~ decay asymmetry. Hyperfine structure and isotopic shift of the 2~ absorption line was determined by Zeeman scanning. In addition a magnetic resonance was performed on the polarized

Investigation of new neutron-rich gold isotopes203Au and205Au

“…1 was constructed from the coincidence relations. From optical pumping experiments the 2~ groundstate-spin is known to be 1/2- [4]. The two excited states at 379 and 467 keV are known from the reactions 2~ and 2~ d) [5-73. We estimated the 2~ grund-state to ground-state /?-decay from the calibrated 31 s-/~--singles component after subtraction of the /%rays to the excited states.…”

Nuclear Radiation Detected Optical Pumping of neutron-deficient Hg isotopes

“…In the case of fi-RADOP the asymmetry is calculated and corrected for background according to (23). This information serves to trace the resonance position, to determine the necessary statistics, and to obtain a preliminary A factor in order to narrow the region where the NMR resonance is to be found.…”

“…The complex 7 spectra, observed farer off stability ask for Ge(Li) detectors and multichannel analysis as described above. Since the two detectors differ in resdlution, spectral response etc., the calculation of signals in analogy to (22), (23) would require a careful peak analysis beforehand. In order to have a quick survey over the results during the experiment, we calculate the signal from the count rates of one detector only according to the following procedure: (i) The integral number of counts taken in both OP modes "a" and "b" is chosen equal.…”

“…It stems predominantly from the non-volatile radioactive daughter products of rig condensed on the walls. This background from radioactive daughters is counted in separate scalers for correcting the signal according to (23). When measuring 7 rays, this procedure easily separates the spectrum of the Hg decay from that of the daughters.…”

“…If the background from daughter activities etc. is known, the asymmetry corrected for background is given by (23) where Tis the total count rate and B is the background count rate. This procedure is adequate to record the odd, parity violating terms occurring in nuclear fl decay.…”