[en] Precise measurements of Fermi superallowed 0⁺ → 0⁺ β decays provide a powerful tool to study the weak interaction properties in the framework of the Standard Model (SM). Collectively, the comparative half-lives (ft) of these transitions allow a sensitive probe of the CVC (Conserved Vector Current) hypothesis and contribute to the most demanding test of the unitarity of the quarks-mixing CKM matrix top-row, by providing, so far, the most accurate determination of its dominant element (V_ud). Until recently, an apparent departure from unity enhanced a doubt on the validity of the minimal SM and thus stimulated a considerable effort in order to extend the study to other Fermi emitters available. The ⁶²Ga and ³⁸Ca are among key nuclei to achieve these precision tests and verify the reliability of the corrections applied to the experimental ft-values. The ⁶²Ga β-decay was investigated at the IGISOL separator, with an experimental setup composed of 3 EUROBALL Clovers for γ-ray detection. Very weak intensity (<1/1000) γ-rays were identified, via β-γ and β-γ-γ correlations, and allowed a partial decay scheme reconstruction in ⁶²Zn. The newly established analog branching-ratio (B.R_A equals 99.893(24) %) was used to compute the universal Ft-value (⁶²Ga). The latter turned out to be in good agreement with the 12 well-known cases. Compatibility between the upper limit set here on the term (δ_IM) and the theoretical prediction suggests that the isospin-symmetry-breaking correction is indeed large for the heavy (A ≥ 62) β-emitters. The study of the ³⁸Ca decay was performed at the CERN-ISOLDE facility. Injection of fluorine into the ion source, in order to chemically select the isotopes of interest, assisted by the REXTRAP Penning trap facility and a time-of-flight analysis, enabled us to eliminate efficiently the troublesome ^38mK. For the first time, the ³⁸Ca half-life is measured with a highly purified radioactive sample. The preliminary result obtained, T1/2(³⁸Ca) 445.8(10) ms, improves the precision on the half-life as determined from previous measurements by a factor close to 10. (author)

[en] Effects of liming and shading on growth and yield of soybean examined. Treatments consisted of two factor, i.e. Liming at three levels (0.5, 1.0 and 1.5 equivalent Al-dd) and shading at four levels (unshaded, shaded with one, two and three layers of Filtering clothes). The experiment was conducted at Research Station, Bogor Research Institute for Food Crops. The treatment was arranged in split plot design. The faction on radiation reduced by one, two and three layers of filtering clothes were 35 percent, 50 percent and 60 percent respectively. Response of the crop liming is independent of shading (no interaction effect). In general, the effect increasing liming was not significant but higher liming reduced growth and yield of the crop. Furthermore, response of the crop to shading was quadratic. It was found that optimum radiation for growth and yield of soybean was between 275 and 340 Iy/day. There was an indication that optimum radiation intensity of more than 340 ly/day narrower planting space was suggested in order to obtain a leaf area index of more 4.0, while in areas with radiation intensity of less than 275 ly/day, wider planting space was preferable in order to obtain a maximum leaf area index of between 3.0 and 3.5

No abstract available

[en] Direct measurements of ($\alpha ,p$) reactions of astrophysical interest with radioactive beams presents serious challenges because of the difficult nature of helium targets and the typical low intensities of the beams. To address this, a new technique has been developed for measurements of low-energy ($\alpha ,p$) reactions with heavy ion beams using an extended ${}^4$He gas target and a newly developed gas recirculating system. The system was used to measure the ${}^4$He(¹⁹F, ${}^1$H)²²Ne reaction as a demonstration. Excitation functions of the ¹⁹F($\alpha ,p$)²²Ne and ¹⁹F($\alpha ,p^{\prime }$)²²Ne${}^{\ast }$ reactions were successfully measured to show the viability of this technique. Details of the approach and future plans are given.

[en] In an experiment performed at the LISE3 facility of GANIL, the isotope ⁵⁴Zn and its decay via two-proton emission were observed for the first time. In addition, preliminary results indicate that three implantation events of ⁴⁸Ni were observed. One of the associated decay events is compatible with a two-proton emission. New data on the decay of ⁴⁵Fe and its two-proton branch were recorded at the same time. The results for ⁵⁴Zn are compared to theory. (orig.)

[en] The half-lives of ³⁸Ca and ³⁹Ca have been measured at ISOLDE of CERN. The REXTRAP facility was used to prepare ultra-clean samples of radioactive nuclei for precision decay spectroscopy. ³⁸Ca is one of the T_z=-1,0⁺ →0⁺β -emitting nuclides used to determine the vector coupling constant of the weak interaction and the V_ud quark-mixing matrix element. The result obtained, T_1/2=443.8(19) ms, is four times more precise than the average of previous measurements. For ³⁹Ca, a half-life of T_1/2=860.7(10) ms is obtained, a result in agreement with the average value from the literature. (orig.)

[en] Beta-decay branching ratios of ⁶²Ga have been measured at the IGISOL facility of the Accelerator Laboratory of the University of Jyvaeskylae. ⁶²Ga is one of the heavier T_z=0, 0⁺→0⁺β-emitting nuclides used to determine the vector coupling constant of the weak interaction and the V_ud quark-mixing matrix element. For part of the experimental studies presented here, the JYFLTRAP facility has been employed to prepare isotopically pure beams of ⁶²Ga. The branching ratio obtained, BR=99.893(24) %, for the super-allowed branch is in agreement with previous measurements and allows to determine the ft value and the universal Ft value for the super-allowed β -decay of ⁶²Ga. (orig.)

[en] The low-energy level structures of ₂₅⁶⁴Mn₃₉ and ₂₅⁶⁶Mn₄₁ were investigated through both the decay of Mn metastable states and the population of levels following the β decay of ⁶⁴Cr and ⁶⁶Cr. The deduced level schemes and tentatively assigned spins and parities suggest the coexistence of spherical and deformed configurations above and below N=40 for the odd-odd Mn isotopes. The low-energy deformed configurations are attributed to the coupling between a proton in a K=1/2^- level with neutrons in either the K=1/2^- or the K=3/2⁺ levels originating from the πp_3/2, νp_1/2, and νg_9/2 single-particle states, respectively.

[en] Studying (α,p) reactions of astrophysical interest with radioactive beams presents serious challenges because of the difficult nature of the target. We have developed a new approach for the measurement of (α,p) reactions using heavy ion beams in inverse kinematics and have measured the ⁴He(¹⁹F,¹H)²²Ne reaction as a demonstration. ¹⁹F beams were used at the Holifield Radioactive Ion Beam Facility (HRIBF) tandem accelerator in Oak Ridge National Laboratory (ORNL) to bombard a large scattering chamber filled with ⁴He gas. Recoiling protons from the reactions were detected by the large area annular silicon strip detector array (SIDAR). The ¹⁹F(α,p) and ¹⁹F(α,p') excitation functions were measured over the energy range of E_c.m. ∼ 1-2.1 MeV, demonstrating the viability of the technique

[en] The proton-rich nucleus ³³Ar has been produced at the low-energy facility SPIRAL at GANIL. Spectroscopic studies of gamma and p emission of this nucleus were performed with the 'Silicon Cube' detection system. The analysis of proton and gamma singles and coincidence spectra allowed us to establish a complete decay scheme of this nucleus. The comparison of the Gamow-Teller strength distribution deduced from our experiment and the theoretical one obtained with the Shell Model permitted the determination of a quenching factor for the Gamow-Teller strength.