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A multi-hit capacity setup was used to study the decay of the dripline nucleus 31Ar, produced at the ISOLDE facility at CERN. A spectroscopic analysis of the beta-delayed three-proton decay of 31Ar is presented for the first time together with a quantitative analysis of the beta-delayed two-proton-gamma-decay. A new method for determination of the spin of low-lying levels in the beta-proton-daughter 30S using proton-proton angular correlations is presented and used for the level at 5.2 MeV, which is found to be either a 3+ or 4+ level, with the data pointing towards the 3+. The half-life of 31Ar is found to be 15.1(3) ms. An improved analysis of the Fermi beta-strength gives a total measured branching for the beta-3p-decay of 3.60(44) %, which is lower than the theoretical value found to be 4.24(43) %. Finally the strongest gamma-transitions in the decay of 33Ar are shown including a line at 4734(3) keV associated to the decay of the IAS, which has not previously been identified., Comment: 12 pages, 14 figures

Resonances just above the proton threshold in 30S affect the 29P(p,gamma)30S reaction under astrophysical conditions. The (p,gamma)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton and gamma partial widths of resonances in 30S. The widths are determined from the beta-2p and beta-p-gamma decay of 31Ar, which is produced at the ISOLDE facility at the European research organization CERN. Experimental limits on the ratio between the proton and gamma partial widths for astrophysical relevant levels in 30S have been found for the first time. A level at 4688(5) keV is identified in the gamma spectrum, and an upper limit on the proton to gamma width of 0.26 (95 % C.L.) is found. In the two-proton spectrum two levels at 5227(3) keV and 5847(4) keV are identified. These levels are previously seen to gamma decay and upper limits on the gamma to proton width of 0.5 and 9, respectively, (95 % C.L.) are found, where the latter differs from previous calculations., 6 pages, 4 figures

Resonances just above the proton threshold in $^{30}$S affect the $^{29}$P$(p,\gamma)^{30}$S reaction under astrophysical conditions. The ($p,\gamma$)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton- and $\gamma$- partial widths of resonances in $^{30}$S. The widths are determined from the $\beta -2p$ and $\beta -p-\gamma$-decay of $^{31}$Ar, which is produced at ISOLDE, CERN. Experimental limits on the ratio between the proton- and $\gamma$- partial widths for astrophysical relevant levels in $^{30}$S have been found for the first time. A level at 4689.2(24)keV is identified in the $\gamma$-spectrum, and an upper limit on the $\Gamma_{p}/\Gamma_{\gamma}$ ratio of 0.26 (95% C.L.) is found. In the two-proton spectrum two levels at 5227(3)keV and 5847(4)keV are identified. These levels were previously seen to $\gamma$-decay and upper limits on the $\Gamma_{\gamma}/\Gamma_{p}$ ratio of 0.5 and 9, respectively, (95% C.L.) are found, where the latter differs from previous calculations. Resonances just above the proton threshold in 30S affect the 29P(p,γ)30S reaction under astrophysical conditions. The (p,γ)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton and γ partial widths of resonances in 30S. The widths are determined from the β2p- and βpγ-decay of 31Ar, which is produced at the ISOLDE radioactive ion beam facility at the European research organization CERN. Experimental limits on the ratio between the proton and γ partial widths for astrophysical relevant levels in 30S have been found for the first time. A level at 4689.2(24)keV is identified in the γ spectrum, and an upper limit on the Γp/Γγ ratio of 0.26 (95% C.L.) is found. In the two-proton spectrum two levels at 5227(3)keV and 5847(4)keV are identified. These levels were previously seen to γ decay and upper limits on the Γγ/Γp ratio of 0.5 and 9, respectively, (95% C.L.) are found, where the latter differs from previous calculations. Resonances just above the proton threshold in 30S affect the 29P(p,gamma)30S reaction under astrophysical conditions. The (p,gamma)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton and gamma partial widths of resonances in 30S. The widths are determined from the beta-2p and beta-p-gamma decay of 31Ar, which is produced at the ISOLDE facility at the European research organization CERN. Experimental limits on the ratio between the proton and gamma partial widths for astrophysical relevant levels in 30S have been found for the first time. A level at 4688(5) keV is identified in the gamma spectrum, and an upper limit on the proton to gamma width of 0.26 (95 % C.L.) is found. In the two-proton spectrum two levels at 5227(3) keV and 5847(4) keV are identified. These levels are previously seen to gamma decay and upper limits on the gamma to proton width of 0.5 and 9, respectively, (95 % C.L.) are found, where the latter differs from previous calculations.

Submitted to J. Phys. G: Nucl. Phys; Expérience GANIL-SPIRAL; Beta-delayed proton and $\gamma$-ray emission from the 32Ar decay has been studied at the low-energy identi cation station of SPIRAL at GANIL. The study of $\beta$ -delayed charged-particle emission and electromagnetic radiation allowed us to achieve a nearly complete decay scheme of the 32Ar nucleus. With the distinction between $\beta$-delayed protons emitted to the ground and to the rst excited state in 31S and the new values of half-life and QEC we have deduced the Gamow-Teller strength distribution over a large part of the QEC window. The GT strength is compared to advanced shell-model calculations. The experimental Gamow-Teller strength is wider distributed than theoretically predicted and the onset of the Gamow-Teller Giant Resonance happens at lower energy. This explains why the deduced value for the quenching factor depends strongly on the explored excitation energy in the daughter nucleus. When the energy window is chosen large enough the standard quenching factor for the sd-shell is recovered.