Pairing-excitation versus intruder states in 68Ni and 90Zr

A discussion on the nature of the 0+ states in 68Ni (Z=28, N=40) is presented and a comparison is made with its valence counterpart 90Zr (Z=40, N=50). Evidence is given for a 0+ proton intruder state at only ~2.2 MeV excitation energy in 68Ni, while the analogous neutron intruder states in 90Zr reside at 4126 keV and 5441 keV. The application of a shell-model description of 0+ intruder states reveals that many pair-scattered neutrons across N=40 have to be involved to explain the low excitation energy of the proton-intruder configuration in 68Ni.Comment: 10 pages, 2 figures, 1 tabl

Neutron-skin thickness of 208^{208}Pb, and symmetry-energy constraints from the study of the anti-analog giant dipole resonance

The $^{208}$Pb($p$,$n\gamma\bar p$) $^{207}$Pb reaction at a beam energy of 30 MeV has been used to excite the anti-analog of the giant dipole resonance (AGDR) and to measure its $\gamma$-decay to the isobaric analog state in coincidence with proton decay of IAS. The energy of the transition has also been calculated with the self-consistent relativistic random-phase approximation (RRPA), and found to be linearly correlated to the predicted value of the neutron-skin thickness ($\Delta R_{pn}$). By comparing the theoretical results with the measured transition energy, the value of 0.190 $\pm$ 0.028 fm has been determined for $\Delta R_{pn}$ of $^{208}$Pb, in agreement with previous experimental results. The AGDR excitation energy has also been used to calculate the symmetry energy at saturation ($J=32.7 \pm 0.6$ MeV) and the slope of the symmetry energy ($L=49.7 \pm 4.4$ MeV), resulting in more stringent constraints than most of the previous studies.Comment: 6 pages, 5 figures. arXiv admin note: text overlap with arXiv:1205.232

The Effect of 12-Weeks Recreational Football (Soccer) for Health Intervention on Functional Movement in Older Adults

There is growing evidence that recreational football offers health benefits for older adults and an important pathway for physical activity for older adult groups. Despite anecdotal evidence that recreational football is beneficial for older adults, no empirical data are available to support this assertion. This study addressed this issue and examined the effects of a 12‐week recreational football intervention on the functional fitness of older adults. Using a pre–post case–control design, thirteen males, aged 61–73 years (mean age ± SD = 66 ± 4 years) undertook a twice‐weekly, 12‐week recreational football for health intervention, and were matched with a control group, comprising thirteen males, aged 62–78 years (mean age ± SD = 66 ± 4 years) who maintained their typical exercise habits during the intervention period. Pre‐ and postintervention, participants underwent assessment of functional fitness, using the Rikli and Jones functional fitness battery as well as an assessment of body fatness, via bioelectrical impedance analysis and dominant handgrip strength using handgrip dynamometry. Results from a series of 2 (pre–post) X 2 (intervention vs. control) repeated‐measures ANOVAs indicate significant pre–post X group interactions for the 30‐second chair stand (p = 0.038, Pƞ2 = 0.168), 8‐foot timed up and go (p = 0.001, Pƞ2 = 0.577) and 6 min walk test (p = 0.036, Pƞ2 = 0.171). In all cases, performance improved significantly after the intervention for the football intervention group but not the control group. There were no significant differences in the 30 s arm curl test or dominant handgrip strength (p > 0.05). There was a non‐significant trend (p = 0.07, Pƞ2 = 0.127) towards a pre–post X group interaction for body fatness, showing a decreased percent body fat for the intervention group over the control group. The results of the present study demonstrate the utility of recreational football as a physical activity intervention in older adults to improve functional movement

Search for Fingerprints of Tetrahedral Symmetry in 156Gd^{156}Gd

Theoretical predictions suggest the presence of tetrahedral symmetry as an explanation for the vanishing intra-band E2-transitions at the bottom of the odd-spin negative parity band in $^{156}Gd$. The present study reports on experiment performed to address this phenomenon. It allowed to determine the intra-band E2 transitions and branching ratios B(E2)/B(E1) of two of the negative-parity bands in $^{156}Gd$.Comment: presented by Q.T. Doan at XLII Zakopane School of Physics: Breaking Frontiers: Submicron Structures in Physics and Biology, May 2008. 5 pages, minor corrections. To be published in the proceeding

First observation of excited states in 173Hg

The neutron-deficient nucleus 173Hg has been studied following fusion-evaporation reactions. The observation of gamma rays decaying from excited states are reported for the first time and a tentative level scheme is proposed. The proposed level scheme is discussed within the context of the systematics of neighbouring neutron-deficient Hg nuclei. In addition to the gamma-ray spectroscopy, the alpha decay of this nucleus has been measured yielding superior precision to earlier measurements.Comment: 5 pages, 4 figure