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The analyzing powers $^{T}T_{10}\phantom{\rule{0.16em}{0ex}},^{T}T_{20}$, and $^{T}T_{30}$ for the $^{12}\mathrm{C}(^{7}\mathrm{Li},t$) reaction were measured and combined with new and previously determined angular distributions to probe the role of multistep processes through coupled channel Born approximation (CCBA) calculations employing new $\ensuremath{\alpha}$-particle spectroscopic amplitudes calculated with the phenomenological shell model in the unrestricted $psd$ space. Good descriptions of the cross-section angular distributions could be obtained except for the larger angles for the 6.05 MeV ${0}^{+}$ and 6.13 MeV ${3}^{\ensuremath{-}}$ states, while the analyzing powers were not generally described. The calculations presented demonstrate the sensitivity of the angular distributions of both the differential cross sections and the analyzing powers to various multistep routes. While the measured analyzing power $^{T}T_{30}$ is roughly zero for all states, the various CCBA calculations produced large and highly oscillatory values for this observable, showing that other multistep processes must be present beyond those taken into account in this work. Standard distorted wave Born approximation (DWBA) calculations were also carried out and these show considerable differences from the CCBA results but the description of the analyzing powers, while slightly improved, is still poor.

The direct component of the 60Fe(n,γ)61Fe cross section was investigated by populating the bound states of the 61Fe nucleus through the (d,pγ) transfer reaction in inverse kinematics using a radioactive beam of 60Fe at 27A MeV. The experiment was performed at GANIL using the MUST2 array and an annular double-sided silicon strip detector for the detection of the light charged particle in coincidence with the photons measured in the EXOGAM γ-ray detectors. For the first time, the spectroscopic factors of the first 3/2−, 5/2−, 1/2−, and 9/2+ states of 61Fe were deduced experimentally from an adiabatic distorted wave approximation analysis of the data. The obtained results show a very good agreement with the shell-model predictions. The calculated direct component of the (n,γ) cross section was found negligible and of about 2% of the total, indicating a dominant resonant component.

gamma-ray and fast-timing spectroscopy were used to study levels in Al-30 populated following the beta(-) decay of Mg-30. Five new transitions and three new levels were located in Al-30. A search was made to identify the third 1(+) state expected at an excitation energy of similar to 2.5 MeV. Two new levels were found, at 3163.9 and 3362.5 keV, that are firm candidates for this state. Using the advanced time-delayed (ATD) beta gamma gamma (t) method we have measured the lifetime of the 243.8-keV state to be T-1/2 = 15(4) ps, which implies that the 243.8-keV transition is mainly of M1 character. Its fast B(M1; 2(+) -> 3(+)) value of 0.10(3) W.u. is in very good agreement with the USD shell-model prediction of 0.090 W.u. The 1801.5-keV level is the only level observed in this study that could be a candidate for the second excited 2(+) state.

The unbound O12 nucleus was studied via the two-neutron transfer (p,t) reaction in inverse kinematics using a radioactive O14 beam at 51 MeV/u. Excitation energy spectra and differential cross sections were deduced by the missing mass method using MUST2 telescopes. We achieved much higher statistics compared to the previous experiments of O12, which allowed accurate determination of resonance energy and unambiguous spin and parity assignment. The O12 resonance previously reported using the same reaction was confirmed at an excitation energy of 1.62±0.03(stat.)±0.10(syst.). MeV and assigned spin and parity of 0+ from a distorted-wave Born approximation analysis of the differential cross sections. Mirror symmetry of O12 with respect to its neutron-rich partner Be12 is discussed from the energy difference of the second 0+ states. In addition, from systematics of known 0+ states, a distinct correlation is revealed between the mirror energy difference and the binding energy after carrying out a scaling with the mass and the charge. We show that the mirror energy difference of the observed 0+ state of O12 is highly deviated from the systematic trend of deeply bound nuclei and in line with the scaling relation found for weakly bound nuclei with a substantial 2s1/2 component. The importance of the scaling of mirror asymmetry is discussed in the context of ab initio calculations near the drip lines and universality of few-body quantum systems.

Nuclear break-up as a tool to study neutron correlations is investigated both theoretically and experimentally. First a time dependent theory going beyond mean field has been developed and shows that correlations between nucleons can be probed through nuclear break-up. Secondly, nuclear break-up of 6 He on 208 Pb target was studied at 20 A.MeV using a secondary beam of 6 He produced by the SPIRAL facility at GANIL. From the correlation function, a strong contribution of the di-neutron configuration of 6 He is found.

The measurement of the Isoscalar Giant Monopole Resonance(GMR) in unstable nuclei remains a major experimental challenge due to low radioactive beam intensities and unfavourable conditions in reverse kinematics. At GANIL, we have tested a new experimental method based on the unique capabilities of the active target Maya to probe the GMR by the inelastic scattering reaction 56Ni(d,d') at 50 AMeV. The preliminary excitation energy spectrum of 56Ni presents a bump between 12 and 25 MeV where isoscalar resonances are expected. © 2007 Elsevier B.V. All rights reserved.

10 pags.; 11 figs.; 2 tabs.; PACS number(s): 23.40.Hc, 29.30.Kv, 27.50.+e, 21.10.Pc; Open Access funded by Creative Commons Atribution Licence 3.0

Analyzing powers and cross sections for the elastic scattering of polarized 7 Li by targets of 6 Li, 7 Li and 12 C are shown to depend only on the properties of the projectile for momentum transfers of less than 1.0 fm −1 . The result of a detailed analysis of the experimental data within the framework of the coupled channels model with ground state reorientation and transitions to the excited states of the projectile and targets included in the coupling schemes are presented. This work suggests that nuclear properties of weakly-bound nuclei can be tested by elastic scattering experiments, independent of the target used, if data are acquired for momentum transfers less than ∼ 1.0 fm −1 .

NESTER; The fast timing $\beta\gamma\gamma(t)$ method was applied to investigate the level lifetimes in $^{30,31,32}$Mg. Levels in Mg have been populated in $\beta$ and $\beta$-delayed neutron emission of Na at the ISOLDE facility. From the $\gamma\gamma$ coincidences a number of new states have been identified and new level schemes were constructed for $^{30,31,32}$Mg. The following preliminary half lives have been determined: T$_{1/2}$ = 3.9(4) ns for the 1789 keV state in $^{30}Mg, T$_{1/2}$ = 133(8) ps and 10.5(8) ns for the 221 keV and 461 keV states in $^{31}$Mg, respectively, and T$_{1/2}$ = 16(4) ps for the 885 keV level in $^{32}$Mg. The 1789 keV level was established as a candidate for the intruder 0$^+$ configuration in $^{30}$Mg with a possible strong E0 branch to the ground state.

4 pages, 3 figures.-- PACS nr.: 23.40.-s.-- Printed version published Apr 2004.-- et al., Beta-decay experiments are a primary source of information for nuclear-structure studies and at the same time complementary to in-beam investigations of nuclei far from stability. Although both types of experiment are mainly based on γ-ray spectroscopy, they face different experimental problems. The so-called Pandemonium effect is a critical problem in β-decay if we are to test theoretically calculated transition probabilities. In this contribution we will present a solution to this problem using total absorption spectroscopy methods. We will also present some examples of experiments carried out with the Total Absorption Spectrometer (TAS) at GSI an describe a new device LUCRECIA recently installed at CERN., This work was partially supported by C.I.C.Y.T. (Spain) under contract AEN96-1662, by MCYT (Spain)contract No. FPA2002-04181-C04-03, by C.S.R. (Poland) grant KBN-2Pp03B-039-13, by R.F.B.R. (Russia)-D.F.G. (Germany) contract 436 RUS 113/201/0(R). Support from the HPMF-CT-1999-00394 project as well as from the European Large Scale Facility program at CERN is also aknowledged.

Primary standards for 7Li polarimetry requiring a measurement of the reaction p(7Lio,a)at03 to the beamline imposeexcessiveradiationdamageonthedetectors.Eliminatingthisdamagerequirestheestablishmentofsecondarystandardsfortheonlinemeasurementofbeampolarization.Acompletesetofanalyzingpowershasbeenobtainedforthescatteringofpolarized7Liby4Hetothe4.63MeVexcitedstateof7Liatabombardingenergyof31.5MeV.Certainanglesatwhichboth the di!erential cross-sections and analyzing powers are large are tabulated as secondary polarization stan-dards. ( 2001 Elsevier Science B.V. All rights reserved. Keywords: Polarized 7Li polarimetry 1. IntroductionEstablishing the magnitude and sign of a beam’spolarizationis now largelyroutinedue tothe greate!ort that has gone into establishing primary po-larization standards for beams of spin 12,1or32nuclei. For heavy-ion beams of spin 32nuclei, thepioneering experimental work of the Heidel-berg}Marburg group showed that angular mo-mentum conservation rules allow a beam tensorpolarization to be determined from measurementsat03or1803[1}3].Theirexperimentswithpolariz-ed7Liand23Nabeamsshowedmanynovelphysicse!ects. Perhaps one of the most startling was thatvirtual projectile excitations can lead to large ana-lyzing powers even when the spin}orbit force issmall [4,5]. Recent experimental work on under-standing the structure of loosely boundhalo nuclei[6] has rekindled interest in studies involving thestable but loosely bound nuclei 6,7Li.All 7Li beam standards are currently based onthe fact that for the p(7Lio,a)a reaction induced bya tensor polarized beam, the tensor analyzingpowers are „20"!1 and

The odd rank analyzing powers T T 10 and T T 30 for 12 C( 7 Li → , 7 Li) 12 C and 12 C( 7 Li → , α ) 15 N have been measured with high precision for a 7 Li → bombarding energy of 34 MeV. The angular distributions of the T T 10 and T T 30 data are strongly correlated, marking the first experimental evidence of a relationship between analyzing powers of different rank. The ratio of T T 30 to T T 10 obeys limits derived from the assumptions that the reaction is both peripheral and well localized in the reaction plane, allowing, for the first time, a third rank analyzing power to contribute to our understanding of 7 Li.

Elastic and inelastic proton scattering to the 21+ state of the single closed shell radioactive nucleus 20 O have been measured in inverse kinematics with a beam energy of 30 MeV/u. The matrix element determined for the 0gs+→21+ transition in this work is compared with the corresponding electromagnetic matrix element to determine the ratio of the neutron and proton multipole matrix elements for this transition, Mn/Mp=2.9(4), which is quite different from the value Mn/Mp=N/Z=1.5 that would be expected for a purely isoscalar transition. A comparison of this result to a corresponding result for 18 O suggests that the strength of the core polarizing interactions between the valence neutrons and the core protons and neutrons is changing significantly with mass.

The inelastic scattering of Ar-40 on Ni-58 has been studied at 44 MeV per nucleon incident energy in coincidence with light particle emission. Besides the well known mechanisms of inelastic excitation, pick up break up and nucleon knock out, a new phenomenon has been observed, giving rise to fast forward moving particles with specific angular correlations. This newly observed mechanism seems to be a generic phenomenon present for various projectile-target combinations and incident energies. Its contribution to the inelastic spectrum has been extracted and a tentative interpretation is given. (C) 1998 Elsevier Science B.V. All rights reserved.

The proton scattering on unstable38S nuclei has been measured in inverse kinematics by using a38S secondary beam at 39 MeV/nucleon. The first 2+ state is seen at 1.2 MeV excitation energy and its angular distribution is extracted. Optical and folding model calculations are compared with the elastic and the 2 1 + angular distributions and the β2 value is determined to be 0.35±0.04. This value is compared with the corresponding result from a Coulomb excitation measurement and theM n/Mp value is extracted.

A 39A MeV {sup 38}S radioactive beam was used with inverse kinematics to measure angular distributions for elastic and inelastic proton scattering from a CH{sub 2} target. Optical potential and folding model calculations are compared with the elastic distribution. Using coupled channel calculations, the {beta}{sub 2} value for the 2{sub 1}{sup +} state is determined to be 0.35{plus_minus}0.04. This value, when compared with the corresponding result from a Coulomb excitation measurement, leads to M{sub n}/M{sub p}=(1.5{plus_minus}0.3) N/Z, indicating an isovector contribution to the 2{sub 1}{sup +} state of {sup 38}S. {copyright} {ital 1997} {ital The American Physical Society}

Elastic and inelastic scattering of protons on unstable 38 S nuclei has been measured in inverse kinematics by using a 38 S secondary beam at 39 MeV/nucleon. The excitation energy spectrum is measured up to 5 MeV. The first 2 + state is seen at 1.2 MeV excitation energy, and strength at around 3–5 MeV is also observed. Angular distributions for inelastic and elastic scattering are shown and compared to optical potential and folding model calculations. The preliminary β 2 value extracted for the first 2 + state is 0.38±0.05.

A study of the Gamow-Teller strength distributions $B$(GT) in the beta decay of ${}^{78}$Sr and ${}^{76,78}$Rb has been made using a total absorption spectrometer (TAS). Following the success in deducing the sign of the deformation for ${}^{76}$Sr, a similar approach is adopted for ${}^{78}$Sr based on a comparison of the measured $B$(GT) with quasiparticle random-phase approximation calculations. This work confirms its previously expected prolate deformation in the ground state. Conclusions about the structure of the odd-odd ${}^{76,78}$Rb isotopes have been drawn based on their measured $B$(GT) distributions.

The quenching of the N=20 shell gap in neutron-rich nuclei is investigated by studying the single-particle structure of 27Ne via neutron transfer using a 26Ne beam. Two low-lying negative-parity intruder states have been observed, the lowest of which is identified as Jπ=3/2−, confirming earlier speculations. A level identified as 7/2− is observed higher in energy than the 3/2−, contrary to the ordering at β-stability and at an energy significantly different from the predictions of previous shell-model calculations. The measured energies and deduced spectroscopic factors are well reproduced in full (0,1)-ℏω 0s-0p-0d-1s-0f-1p calculations in which there is a significant ad hoc reduction (∼0.7 MeV) in the N=20 shell gap.

This is the publisher's version, also available electronically from http://journals.aps.org/prc/abstract/10.1103/PhysRevC.84.011301.

We have undertaken a clinical ground study of proton-induced light flashes (phosphenes). Patients treated at the Institut Curie – Centre de Protontherapie in Orsay, France, received radiation therapy to cure ocular and skull-base cancers. Sixty percent of the patients treated for choroidal melanomas using 73 MeV protons report anomalous phosphenes. Delivering a radiation dose on the retina only is not sufficient to trigger the light flash. The present study may be the first indication of phosphenes triggered by protons of few tens of MeV.

INTEGRAL and RHESSI spacecrafts recently detected the 1.173 and 1.333 MeV γ‐ray lines coming from the 60Fe—60Co—60Ni radioactive decay chain. The long lived isotope 60Fe (T1/2 = 1.5 106y) is believed to be primarily produced in core‐collapse supernovae. However the interpretation of the observations is difficult because of the large uncertainties concerning 59Fe(n,γ)60Fe and 60Fe(n,γ)61Fe cross sections, involved in 60Fe nucleosynthesis.The direct component of the 60Fe(n,γ)61Fe reaction was studied indirectly via the d(60Fe,pγ)61Fe transfer reaction. The experiment performed in GANIL in spring 2009 will allow to determine the excitation energies of the populated excited states of 61Fe and for the first time their spectroscopic factors as well as their transfer angular momentum.I will first give an overview of the astrophysical context, then I will describe the experimental setup and finally present some preliminary results of the ongoing analysis.

An excited state in the proton-rich unbound nucleus $^{12}\mathrm{O}$ was identified at 1.8(4) MeV via missing-mass spectroscopy with the $^{14}\mathrm{O}(p,t)$ reaction at $51\text{ }\text{ }A\mathrm{MeV}$. The spin-parity of the state was determined to be ${0}^{+}$ or ${2}^{+}$ by comparing the measured differential cross sections with distorted-wave calculations. The lowered location of the excited state in $^{12}\mathrm{O}$ indicates the breakdown of the major shell closure at $Z=8$ near the proton drip line. This demonstrates the persistence of mirror symmetry in the disappearance of the magic number 8 between $^{12}\mathrm{O}$ and its mirror partner $^{12}\mathrm{Be}$.

The nuclear break-up of 6He on a 208Pb target was studied at 20A MeV using a secondary beam of 6He produced by the SPIRAL facility at GANIL. $ \alpha$ -particles were detected in coincidence with two neutrons with a large angular coverage and the reaction mechanism was identified. From the distribution of the relative angles between the two neutrons the correlation function was extracted. It shows a strong correlation at small relative angles attributed to the contribution of the di-neutron configuration of 6He .

The reaction 20 O ( d , t ) has been studied in inverse kinematics using a secondary radioactive beam produced with the SPIRAL facility at GANIL. Fragments, light charged particles and gamma rays were measured with the TIARA, MUST2, VAMOS and EXOGAM detectors and preliminary results are reported. The level scheme of 19 O is built and the spin and parity of one state is tentatively assigned using the one-neutron transfer angular distribution.

Expérience GANIL, SPEG, SISSI, Maya; The isoscalar giant monopole resonance (GMR) and giant quadrupole resonance (GQR) have been measured in the Ni56 unstable nucleus by inducing the Ni56(d,d′) reaction at 50A MeV in the Maya active target at the GANIL facility. The GMR and GQR centroids are measured at 19.3±0.5 MeV and 16.2±0.5 MeV, respectively. The corresponding angular distributions are extracted from 3° to 7°. A multipole decomposition analysis using distorted wave Born approximation with random phase approximation transition densities shows that both the GMR and the GQR exhaust a large fraction of the energy-weighted sum rule. The demonstration of this new method opens a broad range of giant resonance studies at intermediate-energy radioactive beam facilities.

The differential cross section angular distribution and the analyzing powers ${}^{T}{T}_{10},{}^{T}{T}_{20}$, for $^{7}\mathrm{Li}$+$^{16}\mathrm{O}$ elastic scattering were measured at ${E}_{\mathrm{lab}}({}^{7}\stackrel{\ensuremath{\rightarrow}}{\mathrm{Li}}$) = 42 MeV. These and previously published $^{7}\mathrm{Li}$+$^{16}\mathrm{O}$ scattering data measured at ${E}_{c.m.}$ = 6.26\ensuremath{-}34.78 MeV were analyzed with the optical model and coupled-reaction channels (CRC) methods to determine the energy dependence of the parameters of the scattering potential. It was found that the optical model potentials are energy independent for $^{7}\mathrm{Li}$ laboratory bombarding energies above 28 MeV, except for a slight decrease in the real potential strength as the bombarding energy increases. The calculations presented show that the tensor analyzing power ${}^{T}{T}_{20}$ arises from a coherent combination of contributions from the ground-state reorientation and central scattering potential. The energy-dependent CRC potentials were shown to describe the data for the $^{16}\mathrm{O}$($^{7}\mathrm{Li}$,$t$)$^{20}\mathrm{Ne}$ reaction.

5 pags., 3 figs. -- 9th International Conference on Clustering Aspects of Nuclear Structure and Dynamics (CLUSTERS'07) 3–7 September 2007, Stratford upon Avon, UK, The break-up of the 18.2 MeV state in 11Be was studied in a 11Li β-decay experiment. We report here on the study of the dominating breakup channels involving na6He or 3n2α in the final state, with special emphasis dedicated in this contribution to the three-particle channel. The two emitted charged particles were detected in coincidence using a highly segmented experimental set-up. The observed experimental energy-vs-energy scatter plot indicates a sequential breakup where nuclei of mass 4, alpha particles, and mass 7, 7He, are involved. A Monte-Carlo simulation of the sequential channel, 11Be* → α + 7He → nα6He was performed and compared to the experimental data and to a simulation of the direct break-up of the 18.2 MeV state nα6He by phase space energy distribution. The energy-versus-energy plot are explained by the sequential simulation but not by the phase space simulation. © 2008 IOP Publishing Ltd.

The \ensuremath{\beta} decay of the neutron-rich nuclei $^{51\ensuremath{-}53}\mathrm{K}$ has been used to populate bound and unbound states in $^{50\ensuremath{-}53}\mathrm{Ca}$. Measurements of \ensuremath{\gamma} rays as well as \ensuremath{\beta}-delayed neutrons enabled detailed decay schemes to be established and levels identified in ${}^{50\ensuremath{-}53}$Ca. A delayed one-neutron emission probability ${P}_{1n}$ of $63\ifmmode\pm\else\textpm\fi{}8$% was determined for the decay of $^{51}\mathrm{K}$. A total of seven new \ensuremath{\gamma} transitions were observed following the decay of $^{51}\mathrm{K}$, and 25 neutron branches were found that enrich the level scheme of $^{51}\mathrm{Ca}$. Delayed neutron emission probabilities of ${P}_{1n}=74.4\ifmmode\pm\else\textpm\fi{}9.3$% and ${P}_{2n}=2.3\ifmmode\pm\else\textpm\fi{}0.3$% were determined for the decay of $^{52}\mathrm{K}$, and 12 new \ensuremath{\gamma} transitions were observed in $^{50,51,52}\mathrm{Ca}$. Three new \ensuremath{\gamma} transitions were observed in $^{52,53}\mathrm{Ca}$ following the \ensuremath{\beta} decay of $^{53}\mathrm{K}$. New limits on the ${P}_{1n}$ and ${P}_{2n}$ values were determined for the \ensuremath{\beta} decay of $^{53}\mathrm{K}$, and a decay scheme was established for $^{53}\mathrm{Ca}$ for the first time. The data obtained here should help clarify the structure of neutron-rich $\mathit{fp}$-shell nuclei around the $N=32\text{\ensuremath{-}}34$ subshell closures.

The \ensuremath{\beta} decay of $^{31}\mathrm{Mg}$ has been investigated at GANIL. The ions were implanted in a silicon detector array surrounded by germanium \ensuremath{\gamma} detectors. \ensuremath{\beta} particles and subsequent \ensuremath{\gamma} rays have been observed. The $^{31}\mathrm{Mg}$ half-life has been measured (${T}_{1/2}=237\ifmmode\pm\else\textpm\fi{}25$ ms) in good agreement with previously reported values. The decay scheme of $^{31}\mathrm{Mg}$ has been enriched with two new low-spin levels and seven new \ensuremath{\gamma} transitions in $^{31}\mathrm{Al}$. Most importantly, very weak feeding to the $^{31}\mathrm{Al}$ ground and lowest excited states has been established. These results are compared to new shell-model calculations in the $\mathit{sd}\text{\ensuremath{-}}\mathit{fp}$ valence space, using an interaction that was modified in order to reproduce the recently established low-energy level scheme of $^{31}\mathrm{Mg}$. A good agreement for all observables is found, supporting the idea that $^{31}\mathrm{Al}$ is outside and $^{31}\mathrm{Mg}$ is inside the so-called ``island of inversion.''

p decays of the neutron-rich nuclei 51,52,53K have been used to populate bound and unbound levels in 50,51,52,53Ca. y r a y spectroscopy as well as P-delayed neutron spectroscopy by time of flight were carried out to obtain a detailed decay scheme to levels in 53Ca, 52Ca, 51Ca and 50Ca. A half-life of 1 1 6 f 6 ms was deduced and new PI, and Pzn delayed neutron emission probabilities have also been determined for 52K. A total of 11 and 3 new y transitions have been observed in the decay of 52K and 53K, respectively. The low-lying level structure of 52Ca is compared to shell-model calculations. Implications of these results on the determination of the Y-Y interaction in the fp shell are discussed.

We report preliminary results on the observation of the isomeric 0 2 + state in 44S. This state, populated in the fragmentation of a 48Ca beam, is located at 1365 ± 1 keV and has a half-life of 2.3 ± 0.3 µs. The observation of this isomer is the first experimental evidence of shape coexistence in 44S which was predicted by various theoretical approaches. In particular, we found a good agreement with shell model calculations.

4 pages, 1 figure.-- Published in: Proceedings of the 22nd International Nuclear Physics Conference (Part 2), Göteborg, Sweden, Jun 27-Jul 2, 2004., Printed version published on Apr 18, 2005., This article explains the importance of β decay studies far from stability with the Total Absorption technique using as an example the decay of Sr-76. In this case the proper measurement of the BGT strength distribution over the full Qβ window, confirmed the ideas proposed long ago by Hamamoto of obtaining information about the nuclear deformation from beta decay.

A novel method of deducing the deformation of the N=Z nucleus Sr-76 is presented. It is based on the comparison of the experimental Gamow-Teller strength distribution B(GT) from its beta decay with the results of quasi-random-phase approximation calculations. This method confirms previous indications of the strong prolate deformation of this nucleus in a totally independent way. The measurement has been carried out with a large total absorption gamma spectrometer, "Lucrecia," newly installed at CERN-ISOLDE.

4 pages, 2 figures.-- Issue title: "Proceedings of the Eighth International Conference on Nucleus-Nucleus Collisions (NN2003, Moscow, Jun 17-21, 2003)"., A new Total Absorption Spectrometer (TAS) called "Lucrecia" has been installed at ISOLDE (CERN) to investigate the β-decay of some nuclei with A≈70-80 in the vicinity of the N=Z line. In this work we report on the decay of the N=Z nucleus 76Sr, measured with a TAS for the first time. The Gamow-Teller strength distribution B(GT) for this decay is presented and compared with theoretical calculations.

A total absorption spectrometer, dedicated to the study of very short-lived atomic species, has been built and installed at the CERN/ISOLDE mass separator. The beta decay of the neutron-deficient Kr-74 nucleus has been studied using this new device. The Gamow-Teller strength distribution has been observed over most of the Q(EC) window, and a total strength of 0.69(3) g(A)(2)/4pi has been measured for states with excitation energy below 3 MeV. Shape mixing in the Kr-74 ground state is inferred from a comparison of the experimental strength distribution with self-consistent, deformed, quasiparticle-random-phase-approximation calculations.

NESTER; Elastic and inelastic proton scattering on 11Be were measured in inverse kinematics up to a 11Be excitation energy of 7 MeV. Continuum discretised coupled-channels (CDCC) calculations using a Click to view the MathML source cluster model of 11Be are able to explain the elastic scattering data. However, for the inelastic scattering angular distributions for 11Be excitation energy bins of 0.5–3 and 3–5.5 MeV the CDCC calculations under-predict the data, indicating the presence of contributions due to the deformed and active 10Be core to the 11Be breakup process.

A new Total Absorption Spectrometer (TAS) called “Lucrecia” has been installed at ISOLDE (CERN) to investigate the β‐decay of some nuclei with A≈70–80 in the vicinity of the N=Z line. In this work we report on the decay of the N=Z nucleus 76Sr, measured with a TAS for the first time. The Gamow‐Teller strength distribution B(GT) for this decay is presented and compared with theoretical calculations.

Measurements of the beta-decay half-lives of neutron-rich nuclei (MgAr) in the vicinity of the N =28 shell closure are reported. Some 22 half-lives have been determined, 12 of which for the first time. Particular emphasis is placed on the results for the Si isotopes, the half-lives of which have been extended from N =25 to 28. Comparison with QRPA calculations suggests that 42 Si is strongly deformed. This is discussed in the light of a possible weakening of the spin–orbit potential.

We compare existing elastic scattering data for $^{6}\mathrm{He}+^{209}\mathrm{Bi}$ with new $^{6}\mathrm{Li}+^{209}\mathrm{Bi}$ data at the same center of mass energies relative to their respective Coulomb barriers. Total reaction cross sections obtained from optical model fits to the $^{6}\mathrm{Li}+^{209}\mathrm{Bi}$ elastic scattering data confirm previous suggestions that the total reaction cross section for $^{6}\mathrm{He}+^{209}\mathrm{Bi}$ is much larger than that for the $^{6}\mathrm{Li}+^{209}\mathrm{Bi}$ system at similar energies relative to the Coulomb barrier. Continuum-discretized coupled channels calculations suggest that the enhanced reaction cross section for $^{6}\mathrm{He}$ is due to the large $E1$ excitation strength to the continuum, absent in $^{6}\mathrm{Li}$. However, this conclusion is still tentative, as the calculations predict a large peak in the total $\ensuremath{\alpha}$ yield at forward angles which the currently available data are unable to confirm, due to their not extending to sufficiently small angles. New precise data for the elastic scattering and total $\ensuremath{\alpha}$ yield at forward angles for the $^{6}\mathrm{He}+^{209}\mathrm{Bi}$ system are required to confirm the contribution of $E1$ excitation to the continuum to the total reaction cross section.

Highly excited states of ${}^{10}\mathrm{Be}$ are formed by the bombardment of ${}^{7}\mathrm{Li}$ targets by ${}^{7}\mathrm{Li}$ beams at 34 and 50.9 MeV from the Florida State University Tandem/LINAC accelerator facility. The states are observed in three-body final state reactions by coincidence measurement of the vector momenta of two of the three particles and reconstruction of the decay energies. We observe decays involving ${}^{7}\mathrm{Li},$ ${}^{8}\mathrm{Li},$ ${}^{9}\mathrm{Li},$ and ${}^{6}\mathrm{He}$ in their ground states, first excited states, and in some cases second excited states. Fifteen of the 18 excitations observed are proposed as possible new states of ${}^{10}\mathrm{Be}.$ A few $\ensuremath{\alpha}$-particle decays of excited boron isotopes are also reported.

The study [Nucl. Phys. A 722 (2003) 424c] of the neutron rich nuclei near the N=28 magic number was performed at GANIL-France. This letter reports on preliminary results concerning isotopes 44,45,46 Ar. Schemes of excited levels were deduced from the γ– γcoincidences. Levels above S n energy were suggested from the γ- n coincidences for 46 Ar.

First results on a β-γ decay spectroscopy experiment of nuclei in the region of N=28 are reported. New β half-lives for nuclei from Mg to Ar have been extracted. For the heavier ones, the new periods of 48Ar and 47Cl are of importance in the understanding of solar abundance ratio 48 Ca 46 Ca . The measured half-lives of Si isotopes have been extended from N=25 to N=28 and are discussed in the light of possible deformation occuring in this region. Finally, preliminary spectroscopy of 45Ar is also reported.

To study the effect of the weak binding energy on the interaction potential between a light exotic nucleus and a target, elastic scattering of ${}^{6}\mathrm{He}$ at 38.3 MeV/nucleon on a ${}^{12}\mathrm{C}$ target was measured at Grand Acc\'el\'erateur National d'Ions Lourds (GANIL). The ${}^{6}\mathrm{He}$ beam was produced by fragmentation. The detection of the scattered particles was performed by the GANIL spectrometer. The energy resolution was good enough to separate elastic from inelastic scattering contributions. The measured elastic data have been analyzed within the optical model, with the real part of the optical potential calculated in the double-folding model using a realistic density-dependent nucleon-nucleon interaction and the imaginary part taken in the conventional Woods-Saxon (WS) form. A failure of the ``bare'' real folded potential to reproduce the measured angular distribution over the whole angular range suggests quite a strong coupling of the higher-order breakup channels to the elastic channel. To estimate the strength of the breakup effects, a complex surface potential with a repulsive real part (designed to simulate the polarization effects caused by the projectile breakup) was added to the real folded and imaginary WS potentials. A realistic estimate of the polarization potential caused by the breakup of the weakly bound ${}^{6}\mathrm{He}$ was made based on a parallel study of ${}^{6}\mathrm{He}{+}^{12}\mathrm{C}$ and ${}^{6}\mathrm{Li}{+}^{12}\mathrm{C}$ optical potentials at about the same energies.