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Excited states in the N=40 isotone $^{62}$Ti were populated via the $^{63}$V(p,2p)$^{62}$Ti reaction at ∼200 MeV/nucleon at the Radioactive Isotope Beam Factory and studied using γ-ray spectroscopy. The energies of the 21+→0gs+ and 41+→21+ transitions, observed here for the first time, indicate a deformed $^{62}$Ti ground state. These energies are increased compared to the neighboring $^{64}$Cr and $^{66}$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 $^{62}$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 $^{60}$Ca.

7 pags., 4 figs., 1 tab., Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a Ca54 beam striking on a liquid hydrogen target at ∼200 MeV/u. A significantly larger cross section to the p3/2 state compared to the f5/2 state observed in the excitation of Ca53 provides direct evidence for the nature of the N=34 shell closure. This finding corroborates the arising of a new shell closure in neutron-rich calcium isotopes. The distorted-wave impulse approximation reaction formalism with shell model calculations using the effective GXPF1Bs interaction and ab initio calculations concur our experimental findings. Obtained transverse and parallel momentum distributions demonstrate the sensitivity of quasifree one-neutron knockout in inverse kinematics on a thick liquid hydrogen target with the reaction vertex reconstructed to final state spin-parity assignments., We would like to express our gratitude to the RIKEN Nishina Center accelerator staff for providing the stable and high-intensity beam andtotheBigRIPSteam for operatingthe secondary beams. S. C. acknowledges the support of the IPA program at RIKEN Nishina Center. J. L. acknowledges the support from Research Grants Council (RGC) of Hong Kong with grant of Early Career Scheme (ECS-27303915). K. O., K. Y., and Y. C. acknowledge the support from Grants-in-Aid of the Japan Society for the Promotion of Science under Grants No. JP16K05352. Y. L. S. acknowledges the support of the Marie Skłodowska-Curie Individual Fellowship (H2020-MSCA-IF-2015-705023). V. V. acknowledges support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017- 84756-C4-2-P. L. X. C. and B. D. L. would like to thank MOST for its support through the Physics Development Program Grant No. ĐTĐLCN.25/18. D. R. and V. W. acknowledge the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Grant No. SFB1245. V. W. and P. K. acknowledge the German BMBF Grant No. 05P19RDFN1. P. K. was also supported by HGSHIRe. D. S. was supported by Projects No. GINOP-2.3.3- 15-2016-00034 and No. NKFIH-NN114454. I. G. has been supported by HIC for FAIR and Croatian Science Foundation under Projects No. 1257 and No. 7194. K. I. H., D. K., and S. Y. P. acknowledge the support from the NRF grant funded bythe Korea government (No. 2016K1A3A7A09005580 and No. 2018R1A5A1025563). This work was also supported by the United Kingdom Science and Technology Facilities Council (STFC) under Grants No. ST/P005314/1 and No. ST/L005816/1, and by NKFIH (128072), and by JSPS KAKENHI Grant No. 16H02179, and by MEXT KAKENHI Grant No. 18H05404. The development of MINOS were supported by the European Research Council through the ERC Grant No. MINOS-258567. Green’s function calculations were performed using HPC resources from the DiRAC Data Intensive service at 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) and from GENCI-TGCC, France (Project No. A0050507392).

The reduced transition probability B(E2;01+→21+) to the first excited 2+ state of the neutron-rich nucleus Te136, with two protons and two neutrons outside the doubly magic Sn132 core, was measured via Coulomb excitation at relativistic energies at the RIKEN Radioactive Isotope Beam Factory. A value of B(E2)=0.191(26) e2b2 was extracted from the measured inelastic scattering cross section on an Au target taking into account the contributions from both Coulomb and nuclear excitations. In addition, an upper limit for the transition strength to a 2+ state of mixed-symmetry character in the excitation energy range of 1.5-2.2 MeV was determined and compared to the predictions of various theoretical calculations. Because of the high statistics gathered in the present experiment the error of the deduced B(E2) value is dominated by the systematic uncertainties involved in the analysis of Coulomb excitation experiments at beam energies around 150 MeV/u. Therefore, the latter are for the first time assessed in detail in the present work.

Drug development for rare diseases is challenged by small populations and limited data. This makes development of clinical trial protocols difficult and contributes to the uncertainty around whether or not a potential therapy is efficacious. The use of data standards to aggregate data from multiple sources, and the use of such integrated databases to develop statistical models can inform protocol development and reduce the risks in developing new therapies. Achieving regulatory endorsement of such models through defined pathways at the US Food and Drug Administration and European Medicines Authority allows such tools to be used by the drug development community for defined contexts of use without further need for discussion of the underlying model(s). The Duchenne Regulatory Science Consortium (D-RSC) has brought together multiple stakeholders to develop a clinical trial simulation tool for Duchenne muscular dystrophy using such an approach. Here we describe the work of D-RSC as an example of how such an approach may be effective at reducing uncertainty in drug development for rare diseases, and thus bringing effective therapies to patients faster.

International audience; The nuclear structure of the Ni76 nucleus was investigated by (p,2p) reaction using a NaI(Tl) array to detect the deexciting prompt γ rays. A new transition with an energy of 2227 keV was identified by γγ and γγγ coincidences. According to these coincidence spectra the observed transition connects a new state at 4147 keV and the previously known 41+ state at 1920 keV. Two weaker transitions were also obtained at 2441 and 2838 keV, which could be tentatively placed to feed the known 21+ state at 990 keV. Our shell-model calculations using the Lenzi, Nowacki, Poves, and Sieja interaction produced good candidates for the experimental proton hole states in the observed energy region, and the theoretical cross sections showed good agreement with the experimental values. Although we could not assign all the experimental states to the theoretical ones unambiguously, the results are consistent with a reasonably large Z=28 shell gap for nickel isotopes in accordance with previous studies.

International audience; Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a Ca54 beam striking on a liquid hydrogen target at ∼200 MeV/u. A significantly larger cross section to the p3/2 state compared to the f5/2 state observed in the excitation of Ca53 provides direct evidence for the nature of the N=34 shell closure. This finding corroborates the arising of a new shell closure in neutron-rich calcium isotopes. The distorted-wave impulse approximation reaction formalism with shell model calculations using the effective GXPF1Bs interaction and ab initio calculations concur our experimental findings. Obtained transverse and parallel momentum distributions demonstrate the sensitivity of quasifree one-neutron knockout in inverse kinematics on a thick liquid hydrogen target with the reaction vertex reconstructed to final state spin-parity assignments.

The reduced transition probability B(E2; 0+ 1 →2+ 1 ) to the first excited 2+ state of the neutron-rich nucleus 136Te, with two protons and two neutrons outside the doubly magic 132Sn core, was measured via Coulomb excitation at relativistic energies at the RIKEN Radioactive Isotope Beam Factory. A value of B(E2)= 0.191(26) e2b2 was extracted from the measured inelastic scattering cross section on an Au target taking into account the contributions from both Coulomb and nuclear excitations. In addition, an upper limit for the transition strength to a 2+ state of mixed-symmetry character in the excitation energy range of 1.5–2.2 MeV was determined and compared to the predictions of various theoretical calculations. Because of the high statistics gathered in the present experiment the error of the deduced B(E2) value is dominated by the systematic uncertainties involved in the analysis of Coulomb excitation experiments at beam energies around 150 MeV/u. Therefore, the latter are for the first time assessed in detail in the present work. Spanish Ministerio de Economía y Competitividad (FPA2014-57196-C5-4-P, FPA2017-84756-C4-2-P, FIS2014-53448-C2-1-P)

Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a Ca- 54 beam striking on a liquid hydrogen target at similar to 200 MeV/u. A significantly larger cross section to the p(3/2), state compared to the f(5/2) state observed in the excitation of Ca-53 provides direct evidence for the nature of the N = 34 shell closure. This finding corroborates the arising of a new shell closure in neutron-rich calcium isotopes. The distorted-wave impulse approximation reaction formalism with shell model calculations using the effective GXPF1Bs interaction and ab initio calculations concur our experimental findings. Obtained transverse and parallel momentum distributions demonstrate the sensitivity of quasifree one-neutron knockout in inverse kinematics on a thick liquid hydrogen target with the reaction vertex reconstructed to final state spin-parity assignments.

14 pags., 11 figs-. 3 tabs., The reduced transition probability B(E2;01+→21+) to the first excited 2+ state of the neutron-rich nucleus Te136, with two protons and two neutrons outside the doubly magic Sn132 core, was measured via Coulomb excitation at relativistic energies at the RIKEN Radioactive Isotope Beam Factory. A value of B(E2)=0.191(26) e2b2 was extracted from the measured inelastic scattering cross section on an Au target taking into account the contributions from both Coulomb and nuclear excitations. In addition, an upper limit for the transition strength to a 2+ state of mixed-symmetry character in the excitation energy range of 1.5-2.2 MeV was determined and compared to the predictions of various theoretical calculations. Because of the high statistics gathered in the present experiment the error of the deduced B(E2) value is dominated by the systematic uncertainties involved in the analysis of Coulomb excitation experiments at beam energies around 150 MeV/u. Therefore, the latter are for the first time assessed in detail in the present work., We thank Dirk Weisshaar for valuable discussions and the staff of the RIKEN Nishina Center accelerator complex for providing high-intensity beams to the experiment. This work was supported by the Spanish Ministerio de Economía y Competitividad under Contracts No. FPA2014-57196-C5-4-P, No. FPA2017-84756-C4-2-P, and No. FIS2014-53448-C2-1-P.

The nuclear structure of the 76 Ni nucleus was investigated by ( p , 2 p ) reaction using a NaI(Tl) array to detect the deexciting prompt γ rays. A new transition with an energy of 2227 keV was identified by γ γ and γ γ γ coincidences. According to these coincidence spectra the observed transition connects a new state at 4147 keV and the previously known 4+1 state at 1920 keV. Two weaker transitions were also obtained at 2441 and 2838 keV, which could be tentatively placed to feed the known 2+1 state at 990 keV. Our shell-model calculations using the Lenzi, Nowacki, Poves, and Sieja interaction produced good candidates for the experimental proton hole states in the observed energy region, and the theoretical cross sections showed good agreement with the experimental values. Although we could not assign all the experimental states to the theoretical ones unambiguously, the results are consistent with a reasonably large Z=28 shell gap for nickel isotopes in accordance with previous studies.