Flavor independent systematics of excited baryons and intra-band transition

Transitions among excited nucleons are studied within a non-relativistic quark model with a deformed harmonic oscillator potential. The transition amplitudes are factorized into the $l$-th moment and a geometrical factor. This fact leads to an analogous result to the ``Alaga-rule'' for baryons.Comment: 4 Pages, 2 figures, Talk given at XVI International Conference on Particles and Nuclei (PaNic02), Osaka, Japan, Sep.30 - Oct.4, 200

Parity assignments in 172,174Yb using polarized photons and the K quantum number in rare earth nuclei

The 100 % polarized photon beam at the High Intensity gamma-ray Source (HIgS) at Duke University has been used to determine the parity of six dipole excitations between 2.9 and 3.6 MeV in the deformed nuclei 172,174 Yb in photon scattering (g,g') experiments. The measured parities are compared with previous assignments based on the K quantum number that had been assigned in Nuclear Resonance Fluorescence (NRF) experiments by using the Alaga rules. A systematic survey of the relation between gamma-decay branching ratios and parity quantum numbers is given for the rare earth nuclei.Comment: 5 pages, 6 figures, to be published in Phys. Rev.

Exact diagonalization of the Bohr Hamiltonian for rotational nuclei: Dynamical gamma softness and triaxiality

Detailed quantitative predictions are obtained for phonon and multiphonon excitations in well-deformed rotor nuclei within the geometric framework, by exact numerical diagonalization of the Bohr Hamiltonian in an SO(5) basis. Dynamical gamma deformation is found to significantly influence the predictions through its coupling to the rotational motion. Basic signatures for the onset of rigid triaxial deformation are also obtained.Comment: 17 pages, 10 figures; to be published Phys. Rev.

Investigation of octupole vibrational states in 150Nd via inelastic proton scattering (p,p'g)

Octupole vibrational states were studied in the nucleus $^{150}\mathrm{Nd}$ via inelastic proton scattering with \unit[10.9]{MeV} protons which are an excellent probe to excite natural parity states. For the first time in $^{150}\mathrm{Nd}$, both the scattered protons and the $\gamma$ rays were detected in coincidence giving the possibility to measure branching ratios in detail. Using the coincidence technique, the $B(E1)$ ratios of the decaying transitions for 10 octupole vibrational states and other negative-parity states to the yrast band were determined and compared to the Alaga rule. The positive and negative-parity states revealed by this experiment are compared with Interacting Boson Approximation (IBA) calculations performed in the (spdf) boson space. The calculations are found to be in good agreement with the experimental data, both for positive and negative-parity states

Nuclear structure of Ac-231

The low-energy structure of 231Ac has been investigated by means of gamma ray spectroscopy following the beta-decay of 231Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a mini-orange electron spectrometer. The decay scheme of 231Ra --> 231Ac has been constructed for the first time. The Advanced Time Delayed beta-gamma-gamma(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus

COMPARATIVE EVALUATION OF BIOACTIVE COMPOUNDS IN Hibiscus sabdariffa AND Syzygium samarangense JUICE EXTRACTS

There is growing interest in the chemical composition of plants towards discovery of more effective biotherapeutic agents. Six bioactive compounds were evaluated from Hibiscus sabdariffa and Syzygium samarangense juice extracts. Both juices had high amounts of saponins, with Syzygium samarangense having higher content (4.77%) than Hibiscus sabdariffa (1.46%). Microbial counts in the juices were in the range of 104 cfu ml-1 of ethanolic extract. The juice extracts showed significant (P 640.05) antimicrobial activities against Escherichia coli , Salmonella typhi and Candida albicans , implying that the juices possess both antibacterial and antifungal properties. The results give substantial scientific credence to the current therapeutic uses of these plants.La composition chimique des plantes s'av\ue8re d'une importance capitale dans la d\ue9couverte des agents bioth\ue9rapeutiques plus efficaces. Six compos\ue9s bioactifs des jus extraits de Hibiscus sabdariffa et Syzygium samarangense \ue9taient \ue9valu\ue9s. Les deux extraits de jus contenaient tous de quantit\ue9s plus \ue9lev\ue9es de saponine, avec 4.77 et 1.46 % pour Syzygium samarangense et Hibiscus sabdariffa, respectivement. Le d\ue9nombrement microbiendans les jusavoisinait 104 cfu ml-1 d'extrait d'\ue9thanol. Les extraits de jus ont montr\ue9 des activit\ue9s antimicrobiennes significatives (P 640.05) contre Escherichia coli , Salmonella typhi et Candida albicans , signifiant que les deux jus poss\ue8dent tous des propri\ue9t\ue9s antimicrobiennes et antifongiques. Les r\ue9sultats font montre d'une cr\ue9dibilit\ue9 scientifique substantielle eu \ue9gard aux usages th\ue9rapeutiques courants de ces plantes.&gt