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Detailed γ-ray spectroscopy of the exotic neon isotope 28Ne has been performed for the first time using the one-neutron removal reaction from 29Ne on a liquid hydrogen target at 240 MeV/nucleon. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for 28Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder p-wave strength providing evidence of the breakdown of the N=20 and N=28 shell gaps. Only a weak, possible f-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large p-wave and small f-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain. Detailed $\gamma$-ray spectroscopy of the exotic neon isotope $^{28}$Ne has been performed for the first time using the one-neutron removal reaction from $^{29}$Ne on a liquid hydrogen target at 240~MeV/nucleon. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for $^{28}$Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder $p$-wave strength providing evidence of the breakdown of the $N=20$ and $N=28$ shell gaps. Only a weak, possible $f$-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large $p$-wave and small $f$-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain.

7 pags., 3 figs., 1 tab., States in the N = 35 and 37 isotopes 55,57Ca have been populated by direct proton-induced nucleon removal reactions from 56,58Sc and 56Ca beams at the RIBF. In addition, the (p, 2p) quasi-free single- proton removal reaction from 56Ca was studied. Excited states in 55K, 55Ca, and 57Ca were established for the first time via in-beam γ -ray spectroscopy. Results for the proton and neutron removal reactions from 56Ca to states in 55K and 55Ca for the level energies, excited state lifetimes, and exclusive cross sections agree well with state-of-the-art theoretical calculations using different approaches. The observation of a short-lived state in 57Ca suggests a transition in the calcium isotopic chain from single-particle dominated states at N = 35 to collective excitations at N = 37., We would like to thank the RIKEN accelerator and BigRIPS teams for providing the high intensity beams. T.K. acknowledges support by RIKEN Junior Research Associate Program. K.W. acknowledges support from the Spanish Ministerio de Ciencia, Innovación y Universidades RYC-2017-22007. RIUMF receives funding via a contribution through the National Research Council of Canada. J.D.H is further supported by NSERC under grants SAPIN-2018-00027 and RGPAS-2018-522453. VS-IMSRG computations were performed with an allocation of computing resources on Cedar at WestGrid and Compute Canada, and on the Oak Cluster at TRIUMF managed by the University of British Columbia department of Advanced Research Computing (ARC). N.S. and Y.U. acknowledge valuable support by “Priority Issue on post-K computer” and KAKENHI grant 20K03981 and 17K05433. C.B. was supported by the UK Science and Technology Facilities Council (STFC) through grants No. ST/L005816/1 and No. ST/V001108/1. SCGF calculations were per- formed by using HPC resources from GENCI-TGCC, France (Contract No. A009057392) and at the DiRAC DiAL system at the University of Leicester, UK, (funded by the UK BEIS via STFC Capital Grants No. ST/K000373/1 and No. ST/R002363/1 and STFC DiRAC Operations Grant No. ST/R001014/1). I.M. was supported by the RIKEN IPA program, F.B. by the RIKEN Special Postdoctoral Researche Program. D.S. acknowledges support from the European Regional Development Fund contract No. GINOP-2.3.3-15-2016-00034 and the National Research, Development and Innovation Fund of Hungary via Project No. K128947. K. I. H., D. K., and S. Y. P. acknowledge the support from the IBS grant funded by the Korea government (No. IBS-R031-D1). The work was further supported by JSPS KAKENHI Grant Nos. JP16H02179, JP18H05404, JP19H00679, and JP21H01114 and the Deutsche Forschungsgemeinschaft (DFG) under Grant No. BL 1513/1-1

The ³⁶Ca nucleus has several fascinating properties linked to nuclear structure, with the study of isospin symmetry breaking effects and shell gap evolution at the proton drip-line. Moreover, the energy and structure of its excited states have an astrophysical interest in particular for the study of the key reaction ³⁵K(p,γ)³⁶Ca involved in the rp-process occurring in X-ray bursts.Isospin symmetry is one of the most fundamental symmetries in nuclei and is related to charge independence of the strong interaction. If the isospin symmetry is strictly preserved, the level schemes of mirror nuclei (with exchanged number of protons and neutrons) should be identical. The Coulomb interaction breaks the isospin symmetry and gives rise to shift in excitation energy between analogue states in mirror nuclei called Mirror Energy Differences (MED). In the case of the mirror pair ³⁶Ca-³⁶S, the Coulomb interaction act as a magnifying glass of the nuclear structure, which effects are scrutinized in this work.The nuclear astrophysics motivation is linked to the indirect measurement of the ³⁵K(p,γ)³⁶Ca reaction rate to better understand the luminosity profile emitted during Type Ia X-ray burst. Indeed, this reaction has been identified as one of the ten (p,γ) reactions that could significantly impact the shape of the calculated X-ray burst light curve. The present experiment aims at studying the energy, spin values, proton spectroscopic factors and widths of the excited states of astrophysical interest in ³⁶Ca. These relevant spectroscopic information are used to reinvestigate the ³⁵K(p,γ)³⁶Ca reaction rate and its corresponding uncertainties and determine its impact on the X-ray burst’s light curve.³⁶Ca was studied at GANIL by means of the ³⁷Ca(p,d) and ³⁸Ca(p,t) transfer reactions at about 50 MeV/nucleons. Radioactive beams of ³⁷Ca and ³⁸Ca, produced with the LISE spectrometer, were tracked by two sets of position-sensitive detectors before impinging on a liquid Hydrogen cryogenic target. 6 MUST2 telescopes (Silicon DSSD and CsI crystals) were used to identify and measure light particles emitted during the transfer reaction. An assembly of three detectors (ionization chamber, drift chamber and plastic scintillator) were used to detect the outgoing heavy ion in the exit channel. The detection of both light and heavy ejectiles ensured a complete determination of the kinematics of the reaction, an assignment of the transferred angular momentum L of all states produced, and a very reduced amount of background.The full spectroscopy of ³⁶Ca has been obtained and new excited states have been identified. Colossal MED have been observed in the newly discovered intruder states of ³⁶Ca. The proton correlation, viewed from the two-proton decay of highly excited states, has been also studied. With the experimental results and the help of shell-model calculations, the ³⁵K(p,γ)³⁶Ca reaction rate has been re-evaluated and constrained with meaningful statistical uncertainty. Besides ³⁶Ca, the first study of the spectroscopy of ³⁵Ca (including its mass measurement) will also be presented., Le noyau de ³⁶Ca possède plusieurs propriétés fascinantes liées à la structure nucléaire, avec l'étude des effets de brisure de la symétrie d'isospin et de l'évolution de l’espacement des couches à la limite de non-liaison. De plus, l’énergie et la structure de ses états excités ont un intérêt astrophysique notamment pour l'étude de la réaction ³⁵K(p,γ)³⁶Ca qui est impliquée dans le processus rp se produisant dans les sursauts X.La symétrie isospin est l'une des symétries les plus fondamentales du noyau et est liée à l'indépendance de charge de l'interaction forte. Si la symétrie d'isospin est strictement préservée, les schémas de niveaux des noyaux miroirs (avec un nombre échangé de protons et de neutrons) devraient être identiques. L'interaction coulombienne brise la symétrie d'isospin et donne lieu à un décalage de l'énergie d'excitation entre les états analogues des noyaux miroirs, appelé différence d'énergie miroir. Dans le cas de la paire miroir ³⁶Ca-³⁶S, l'interaction coulombienne agit comme une loupe de la structure nucléaire, dont les effets sont examinés dans ce travail.La motivation d'astrophysique nucléaire est liée à la mesure indirecte du taux de la réaction ³⁵K(p,γ)³⁶Ca afin de mieux comprendre le profil de luminosité émis lors des sursauts X de Type Ia. En effet, cette réaction a été identifiée comme l'une des dix réactions (p,γ) qui pourraient avoir un impact significatif sur la forme de la courbe de lumière calculée des sursauts X. La présente expérience vise à étudier l'énergie, les valeurs de spin, les facteurs spectroscopiques protons et les largeurs des états excités d'intérêt astrophysique dans le ³⁶Ca. Les informations spectroscopiques pertinentes sont utilisées pour réexaminer le taux de la réaction ³⁵K(p,γ)³⁶Ca et ses incertitudes correspondantes et déterminer son impact sur la courbe de lumière des sursauts X.Le ³⁶Ca a été étudié au GANIL au moyen des réactions de transfert ³⁷Ca(p,d) et ³⁸Ca(p,t) à environ 50 MeV/nucléons. Des faisceaux radioactifs de ³⁷Ca et ³⁸Ca, produits avec le spectromètre LISE, ont été mesurés par deux ensembles de détecteurs sensibles à la position avant d'interagir avec une cible cryogénique d'hydrogène liquide. 6 télescopes MUST2 (cristaux de silicium DSSD et CsI) ont été utilisés pour identifier et mesurer les particules légères émises pendant la réaction de transfert. Un ensemble de trois détecteurs (chambre d'ionisation, chambre de dérive et scintillateur en plastique) ont été utilisés pour détecter l'ion lourd sortant dans le canal de sortie. La détection des éjectiles légers et lourds a permis une détermination complète de la cinématique de la réaction, une attribution du moment angulaire transféré L de tous les états produits, et une réduction significative du bruit de fond.La spectroscopie complète du ³⁶Ca a été obtenue et de nouveaux états excités ont été identifiés. De très grandes différences d'énergie miroir ont été observées dans les nouveaux états intrus du ³⁶Ca. La corrélation des protons, vue à partir de la désintégration en deux protons des états hautement excités, a également été étudiée. Grâce aux résultats expérimentaux et aux calculs de modèles en couche, le taux de réaction ³⁵K(p,γ)³⁶Ca a été réévalué et fortement contraint avec une incertitude statistique pertinente. Outre le ³⁶Ca, la première étude de la spectroscopie du ³⁵Ca (y compris la mesure de sa masse) sera également présentée.

6 pags., 4 figs., 2 tabs., The change of the shell structure in atomic nuclei, so-called “nuclear shell evolution”, occurs due to changes of major configurations through particle-hole excitations inside one nucleus, as well as due to variation of the number of constituent protons or neutrons. We have investigated how the shell evolution affects Gamow-Teller (GT) transitions that dominate the β decay in the region below 132Sn using the newly obtained experimental data on a long-lived isomer in 127Ag. The T1/2=67.5(9) ms isomer has been identified with a spin and parity of (27/2+) at an excitation energy of 1942−20+14 keV, and found to decay via an internal transition of an E3 character, which competes with the dominant β-decay branches towards the high-spin states in 127Cd. The underlying mechanism of a strong GT transition from the 127Ag isomer is discussed in terms of configuration-dependent optimization of the effective single-particle energies in the framework of a shell-model approach., Part of the WAS3ABi was supported by the Rare Isotope Science Project which is funded by MSIP and NRF of Korea. This work was supported by the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K100835, the U.S. DOE, Office of Nuclear Physics (Contract No. DE-AC02-06CH11357), NRF2016R1A5A1013277 and NRF-2013M7A1A1075764, the Spanish Ministerio de Economía y Competitividad under contract FPA2017- 84756-C4-2-P, the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF (Contract No. 300096), German BMBF under Contract No: 05P12PKFNE, JSPS KAKENHI Grant No. 24740188 and 25247045, the National Natural Science Foundation of China (Nos. 11505302, 11575112, 11775316), the National Key Program for S&T Research and Development (No. 2016YFA0400501), and STFC (UK).

7 pags., 4 figs., 1 tab., Excited states in the N=40 isotone Ti were populated via the V(p,2p)Ti reaction at ∼200 MeV/nucleon at the Radioactive Isotope Beam Factory and studied using γ-ray spectroscopy. The energies of the 2 →0 and 4 →2 transitions, observed here for the first time, indicate a deformed Ti ground state. These energies are increased compared to the neighboring Cr and Fe isotones, suggesting a small decrease of quadrupole collectivity. The present measurement is well reproduced by large-scale shell-model calculations based on effective interactions, while ab initio and beyond mean-field calculations do not yet reproduce our findings. The shell-model calculations for Ti show a dominant configuration with four neutrons excited across the N=40 gap. Likewise, they indicate that the N=40 island of inversion extends down to Z=20, disfavoring a possible doubly magic character of the elusive Ca., We thank the RIKEN Nishina Center accelerator staff and the Bi-gRIPS team for the stable operation of the high-intensity Zn beam and for the preparation of the secondary beam setting. K.O. ac-knowledges the support by Grant-in-Aid for Scientific Research of the Japan Society for the Promotion of Science (JSPS) JP16K05352. A.P. is supported in part by the Ministerio de Ciencia, Innovación y Universidades (Spain), Severo Ochoa Programme SEV-2016-0597 and grant PGC-2018-94583. F.B. is supported by the RIKEN Spe-cial Postdoctoral Researcher Program. L.X.C. and B.D.L. would like to thank the Vietnam Ministry of Science and Technology (MOST) for its support through the Physics Development Program Grant No. ÐTÐLCN.25/18. I.G. has been supported by HIC for FAIR and Croatian Science Foundation under projects no. 1257 and 7194. D. So. was supported by the the European Regional Develop-ment Fund contract No. GINOP-2.3.3-15-2016-00034 and the National Research, Development and Innovation Fund of Hungary via Project No. K128947. V.V. acknowledges support from the Span-ish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P. K.I.H., D.K. and S.Y.P. acknowledge the sup-port from the National Research Foundation of Korea grant No. 2018R1A5A1025563 and 2019M7A1A1033186. The development of MINOS was supported by the European Research Council through the ERC Grant No. MINOS-258567. This work was also supported by the JSPS KAKENHI Grant No. 18K03639, MEXT as “Priority is-sue on post-K computer” (Elucidation of the fundamental laws and evolution of the universe), the Joint Institute for Computational Fundamental Science (JICFuS), the CNS-RIKEN joint project for large-scale nuclear structure calculations, Natural Sciences and Engineering Research Council (NSERC) of Canada, the Deutsche Forschungsgemeinschaft – Projektnummer 279384907 – SFB 1245, the PRISMA Cluster of Excellence, and the BMBF under Contracts No. 05P18RDFN1 and 05P19RDFN1. TRIUMF receives funding via a contribution through the National Research Council Canada. Com-putations were performed at the Jülich Supercomputing Center (JURECA)

International audience; We report on the first γ -ray spectroscopy of 51,53 K produced via the 52,54 Ca( p ,2 p ) reactions at ∼250 MeV/nucleon. Unambiguous final-state angular-momentum assignments were achieved for beam intensities down to few particles per second by using a new technique based on reaction vertex tracking combined with a thick liquid-hydrogen target. Through γ -ray spectroscopy and exclusive parallel momentum distribution analysis, 3/2 + ground states and 1/2 + first excited states in 51,53 K were established quantifying the natural ordering of the 1d3/2 and 2s1/2 proton-hole states that are restored at N = 32 and 34. State-of-the-art ab initio calculations and shell-model calculations with improved phenomenological effective interactions reproduce the present data and predict consistently the increase of the E (1/2 1+ ) - E (3/2 1+ ) energy differences towards N = 40.

9 pags., 5 figs., 2 tabs., The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 2 state of C. The experimental findings support the notion of a moderate reduction of the proton 1p−1p spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline., This work was supported by the Royal Society award UF150476, UK STFC awards ST/M006433/1 and ST/P003885/1, U.S. Department of Energy, Office of Nuclear Physics, contract No. DE-AC02- 05CH11231 (LBNL), the German Federal Ministry of Education and Research (BMBF projects 05P15RDFN1, 05P15WOFNA and 05P19RDFN1), the GSI-TU Darmstadt cooperation agreement, the State of Hesse through the LOEWE center HIC for FAIR, the Helmholtz-Gemeinschaft through the graduate school HGS-HIRe and Young Investigators Grants, and the Swedish Research Council under contract number 621-2011-5324. This work was also supported by the Spanish research grants (Ministerio Ciencia e Innovación), FPA2015-64969-P, FPA2015-69640-C2-1-P, FPA2017- 87568-P, PGC2018-099746-B-C21, RTI2018-098868-B-I00, Undidad de Excelencia María de Maeztu under project MDM-2016.0692, and the Xunta de Galicia research grant GRC ED431C 2017/54. This work was partly supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project-ID 279384907 - SFB 1245. C.A.B. acknowledges support from the U.S. NSF Grant No. 1415656, and U.S. DOE Grant No. DE-FG02-08ER41533.

International audience; The excited states in $^{63,65,67}$Mn have been studied via in-beam \begin{document}$\gamma$\end{document}-ray spectroscopy following the knockout reaction of $^{68}$Fe by bombarding a liquid hydrogen target. Similar level schemes have been established for the three isotopes, and the level schemes consist of the 11/2$^{–}$, 9/2$^{–}$, 7/2$^{–}$ and 5/2$_{g.s.}^{–}$ states, which are connected by \begin{document}$\Delta I = 1$\end{document}. The level sequences of $^{65,67}$Mn show features of strongly coupled rotational band with \begin{document}$K^{\pi} = 5/2^{-}$\end{document} expected for the well deformed nuclei. Large-scale shell-model calculations using the modified LNPS (LNPSm) effective interaction reproduce the observed levels remarkably well and suggest the dominance of 4-particle-4-hole (\begin{document}$4p-4h$\end{document}) neutron configurations and 1-particle-1-hole (\begin{document}$1p-1h$\end{document}) proton configurations for all the states. The experimental results show an enhancement of Urca neutrino cooling in the accreted neutron crust associated with \begin{document}$A = 63$\end{document} nuclei and rule out significant cooling from \begin{document}$A = 65,67$\end{document}.

Isomeric states in 59,61Ti have been populated in the projectile fragmentation of a 345 AMeV 238U beam at the Radioactive Isotope Beam Factory. The decay lifetimes and delayed gamma-ray transitions were measured with the EURICA array. Besides the known isomeric state in 59Ti, two isomeric states in 61Ti are observed for the first time. Based on the measured lifetimes, transition multipolarities as well as tentative spins and parities are assigned. Large-scale shell model calculations based on the modified LNPS interaction show that both 59Ti and 61Ti belong to the Island of Inversion at N=40 with ground state configurations dominated by particle-hole excitations to the g_9/2 and d_5/2 orbits., Phys. Lett. B accepted

The low-lying unbound level structure of the halo nucleus $^{19}\textrm{C}$ has been investigated using single-neutron knockout from $^{20}\textrm{C}$ on a carbon target at 280 MeV/nucleon. The invariant mass spectrum, derived from the momenta of the forward going beam velocity $^{18}\textrm{C}$ fragment and neutrons, was found to be dominated by a very narrow near threshold ($E_\textrm{rel}$ = 0.036(1) MeV) peak. Two less strongly populated resonance-like features were also observed at $E_\textrm{rel}$ = 0.84(4) and 2.31(3) MeV, both of which exhibit characteristics consistent with neutron $p$-shell hole states. Comparisons of the energies, measured cross sections and parallel momentum distributions to the results of shell-model and eikonal reaction calculations lead to spin-parity assignments of $5/2^+_1$ and $1/2^-_1$ for the levels at $E_x$ = 0.62(9) and 2.89(10) MeV with $S_n$ = 0.58(9) MeV. Spectroscopic factors were also deduced and found to be in reasonable accord with shell-model calculations. The valence neutron configuration of the $^{20}\textrm{C}$ ground state is thus seen to include, in addition to the known $1s^2_{1/2}$ component, a significant $0d^2_{5/2}$ contribution. The level scheme of $^{19}\textrm{C}$, including significantly the $1/2^-_1$ cross-shell state, is well accounted for by the YSOX shell-model interaction developed from the monopole-based universal interaction., Physics Letters B, in press

In two (d,3He) transfer reactions with MUST2 at GANIL and the split-pole at Orsay, we have determined the position of the proton-hole states in the neutron-rich 71Cu (N=42) and 69Cu (N=40) isotopes. We have found that in 71Cu the hole strength of the f7/2 orbital lies at higher excitation energies than expected. From beta-decay and laser spectroscopy, the f5/2 first excited particle state in these isotopes was known to come down rapidly in energy when passing N=40 and even become the ground state in 75Cu. This sudden energy shift has been explained in a number of theoretical works. The prediction for the f7/2 spin-orbit partner was that it would change in energy too through a related effect. Experimentally, the f7/2 proton-hole state is not known for N>40. In 71Cu two 7/2- states around 1 MeV are candidates to be a proton-hole.The experiment at GANIL took place in March 2011. A secondary beam of 72Zn at 38 AMeV was produced by fragmentation and purified through the LISE spectrometer. The transfer reaction in inverse kinematics was studied with the MUST2 detectors plus four 20 micrometer silicon detector to identified the 3He of low kinetic energy. The excitation spectrum of 71Cu was reconstruct thanks to the missing mass method and the angular distributions were extracted and compared with a reaction model using the DWUCK4 and DWUCK5 code. From this work no states have been populated around 1 MeV concluding that the centroid of the f7/2 lies at higher excitation energy. We then remeasured the single-particle strength in 69Cu in the corresponding (d,3He) reaction at Orsay in March 2013 in order to extend the existing data where 60% of the f7/2 strength is missing and make sure that there is a consistent analysis of spectroscopic factors between both isotopes in order to well understood and well quantify the evolution of the f7/2 orbital when we start filling the g9/2 orbital. In this second experiment we have performed the reaction in direct kinematics using a deuteron beam at 27 MeV provided by the tandem and a target of 70Zn. In this work we were able to extract three new angular distributions and we have measured a new part of the f7/2 strength.Finally in order to interpret the results we have obtained from those two experiments, state-of-the-art shell-model calculations have been carried out in collaboration with the Strasbourg group using the Antoine code. The valence space consists in a core of 48Ca with the valence orbitals for protons f7/2, p3/2, f5/2, p1/2 and the orbitals p3/2, f5/2, p1/2, g9/2, d5/2 for neutrons. The calculations have been done allowing 8p-8h and show that the strength is indeed at high energy and no f7/2 proton-hole state lies around 1 MeV in 71Cu.; A l'aide de deux réactions de transfert (d,3He), la première avec MUST2 au GANIL et la deuxième avec le split-pole à Orsay, nous avons déterminé la position des états trous de protons dans les noyaux riches en neutrons : le 71Cu (N=42) et le 69Cu (N=40).A partir de la désintégration beta et de la spectroscopie laser, on sait que l'état excité f5/2 chute brutalement en énergie pour N>40 et devient même l'état fondamental dans le 75Cu. Cette chute en énergie a été expliqué par des travaux théoriques notamment à cause de la force tenseur entre les protons et les neutrons. La prédiction sur le partenaire spin-orbite f7/2 est qu'il devrait sentir également un effet à cause de cette force. Expérimentalement, les états trous de proton f7/2 ne sont pas connus pour N>40. Dans le 71Cu, deux états 7/2- sont connus autour de 1 MeV d'énergie d'excitation et sont des possibles candidats pour correspondre à cet état trou de proton. L'expérience au GANIL a eu lieu en mars 2011. Un faisceau secondaire de 72Zn à 38 AMeV a été produit par fragmentation et purifié à travers le spectromètre LISE. La réaction de transfert en cinématique inverse a été étudié à l'aide des télescopes MUST2 plus quatre détecteurs de silicium de 20 micromètres dans le but d'identifier les 3He de basse énergie. Le spectre en énergie d'excitation du 71Cu a été reconstruit grâce à la méthode de la masse manquante, les distributions angulaires ont été extraite et comparé avec un modèle de réaction utilisant les codes DWUCK4 et DWUCK5. A partir de ce travail au GANIL, aucun état n'a été peuplé autour de 1 MeV concluant que le centroid de la force réside à plus haute énergie d'excitation.Nous avalons également mesuré une nouvelle fois la les états trous de proton dans le 69Cu avec la même réaction de transfert mais cette fois en cinématique directe à Orsay dans le but d'étendre les données actuelles sur ce noyau où 60% de la force f7/2 est manquante et dans le but également d'avoir une analyse consistante des facteurs spectroscopiques entre les deux noyaux. Cette analyse consistante nous permet de pouvoir comparer l'évolution du centroid de la force entre les deux isotopes quand l'orbite neutron g9/2 commence à se remplir. Dans cette seconde expérience, nous avons utilisé un faisceau de deuton à 27 MeV produit par le tandem et une cible de 70Zn. Nous avons pu extraire trois nouvelles distributions angulaires et mesurer une nouvelle partie de la force f7/2.Enfin, pour pouvoir interpréter nos résultat, des calculs modèle en couche ont été effectué par le groupe de Strasbourg avec le code Antoine. L'espace de valence utilisé consiste en un coeur 48Ca avec les orbitales protons f7/2, p3/2, f5/2, p1/2 et les orbitales neutron p3/2, f5/2, p1/2, g9/2, d5/2. Les calculs inclus jusqu'à 8p-8h et montrent que la force se situe en effet à haute énergie d'excitation et qu'aucun état de trou de proton n'est calculé autour de 1 MeV.