Suchergebnisse

22 pags., 8 figs., 4 tabs., 1 app. ; A dedicated spectroscopic study of the β decay of Cd127 was conducted at the IGISOL facility at the University of Jyväskylä. Following high-resolution mass separation in a Penning trap, β-γ-γ coincidences were used to considerably extend the decay scheme of In127. The β-decaying 3/2+ and 11/2- states in Cd127 have been identified with the Cd127 ground state and the 283-keV isomer. Their respective half-lives have been measured to 0.45(812)s and 0.36(4) s. The experimentally observed β feeding to excited states of In127 and the decay scheme of In127 are discussed in conjunction with large-scale shell-model calculations. ; The authors thank the accelerator staff at the University of Jyväskylä. This work is supported by the European Union's Horizon 2020 research and innovation programme Grant No. 654002 (ENSAR2), the Swedish Research Council (VR 2013- 4271), the Knut and Alice Wallenberg foundation (KAW 2015.0021), the Academy of Finland under the Finnish Centre of Excellence Program (Nuclear and Accelerator Based Physics Research at JYFL 2012-2017), and the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P. The support from the Academy of Finland under Grants No. 275389, No. 284516, No. 312544, and No. 295207 is acknowledged. A.K. and L.C. acknowledge the funding from the European Union's Horizon 2020 research and innovation program under Grant No. 771036 (ERC CoG MAIDEN). U.F. acknowledges support from the Birgit and Hellmuth Hertz Foundation of the Royal Physiographic Society in Lund.

16 pags., 9 figs., 5 tabs. ; A first -ray study of spectroscopy was performed at the Radioactive Isotope Beam Factory with projectiles at 217 MeV/nucleon, impinging on the liquid hydrogen target of the MINOS device. Prompt deexcitation rays were measured with the NaI(Tl) array DALI2. Through the one-proton knockout reaction , a spin assignment could be determined for the low-lying states of from the momentum distribution obtained with the SAMURAI spectrometer. A spin-parity is deduced for the ground state of , similar to the recently studied isotope . The evolution of the energy difference is compared to state-of-the-art theoretical predictions. ; We thank the RIKEN Nishina Center accelerator staff for their work in the primary beam delivery and the BigRIPS team for preparing the secondary beams. The development of MINOS has been supported by the European Research Council through the ERC Grant No. MINOS258567. B.D.L., L.X.C., and N.D.T. acknowledge support from the Vietnam Ministry of Science and Technology under Grant No. ĐTCB.01/21/VKHKTHN. M.G.R. and A.M.M. are supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (including FEDER funds) under project FIS2017-88410-P. F.B. was supported by the RIKEN Special Postdoctoral Researcher Program. Y.L.S. acknowledges the support of Marie Skłodowska-Curie Individual Fellowship (H2020-MSCAIF-2015-705023) from the European Union. I.G. has been supported by HIC for FAIR and Croatian Science Foundation. R.-B.G. is supported by the Deutsche Forschungsgemeinschaft (DFG) under Grant No. BL 1513/1-1. 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). P.K. was supported in part by the BMBF Grant No. 05P19RDFN1 and HGS-HIRe. D.So. has been supported by 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. This work was supported in part by JSPS KAKENHI Grants No. JP16H02179, No. JP18H05404, and No. JP20K03981. J.D.H. and R.S. acknowledge the support from NSERC and the National Research Council Canada. This work was supported by the Office of Nuclear Physics, U.S. Department of Energy, under Grants No. de-sc0018223 (NUCLEI SciDAC-4 collaboration) and the FieldWork Proposal ERKBP72 at Oak Ridge National Laboratory (ORNL). Computer time was provided by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program. This research used resources of the Oak Ridge Leadership Computing Facility located at ORNL, which is supported by the Office of Science of the Department of Energy under Contract No. DE-AC05-00OR22725. GGF calculations were performed by using HPC resources from GENCI-TGCC (Contracts No. A007057392 and No. A009057392) and at the DiRAC Complexity system at the University of Leicester (BIS National E-infrastructure capital Grant No. ST/K000373/1 and STFC Grant No. ST/K0003259/1). This work was supported by the United Kingdom Science and Technology Facilities Council (STFC) under Grant No. ST/L005816/1 and in part by the NSERC Grants No. SAPIN-2016-00033, No. SAPIN-2018-00027, and No. RGPAS-2018-522453. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. J.D.H. thanks S. R. Stroberg for the IMSRG++ code used to perform the VSIMSRG calculations [86]. N.T.T.P. was funded by Vingroup Joint Stock Company and supported by the Domestic Ph.D. Scholarship Programme of Vingroup Innovation Foundation (VINIF), Vingroup Big Data Institute (VINBIGDATA), code VINIF.2020.TS.52.

7 pags., 3 figs., 1 tab. ; We report on the first γ-ray spectroscopy of K produced via the Ca(p,2p) 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 K were established quantifying the natural ordering of the 1d and 2s 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 ) - E(3/2 ) energy differences towards N = 40. ; We are very grateful to the RIKEN Nishina Center accelerator staff for providing the stable and high-intensity zinc beam and to the BigRIPS team for the smooth operation of the secondary beams. The development of MINOS has been supported by the European Research Council through the ERC Grant No. MINOS-258567. Green's function calculations were performed using HPC resources from GENCI-TGCC, France (Projects A0030507392 and A0050507392) and from the DiRAC Data Intensive service at Leicester, UK (funded by the UK BEIS via STFC capital grants ST/K000373/1 and ST/R002363/1 and STFC DiRAC Operations grant ST/R001014/1). This work (C. B.) was also supported by the United Kingdom Science and Technology Facilities Council (STFC) under Grants No. ST/P005314/1 and No. ST/L005816/1. K. O. acknowledges the support by Grant-in-Aid for Scientific Research JP16K05352. Y. L. S. acknowledges the support of Marie Skłodowska-Curie Individual Fellowship (H2020-MSCA-IF-2015-705023) from the European Union and the support from the Helmholtz International Center for FAIR. The valuable discussions with C. Qi are gratefully acknowledged. H. N. L. acknowledges the support from the Enhanced Eurotalents program (PCOFUND-GA-2013-600382) co-funded by CEA and the European Union. H. N. L. and A. O. acknowledge the support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project No. 279384907-SFB 1245. Y. L. S. and A. O. acknowledge the support from the Alexander von Humboldt Foundation. 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. I.G. has been supported by HIC for FAIR and HRZZ under project No. 1257 and 7194. K. I. H., D. K. and S. Y. P. acknowledge the support from the NRF grant funded by the Korea government (No. 2017R1A2B2012382 and 2019M7A1A1033186). F. B. acknowledge the support from the RIKEN Special Postdoctoral Researcher Program. D.S. was supported by projects No. GINOP-2.3.3-15-2016-00034 and No. K128947. V. V. acknowledges support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P. V. W. acknowledges support from BMBF grants 05P15RDFN1, 05P19RDFN1 and DFG grant SFB 1245. P. K. acknowledges support from HGS-HIRe and BMBF grant 05P19RDFN1. This work was also supported by NKFIH (128072).

9 pags., 6 figs., 4 tabs. ; Low-lying excited states in the N=32 isotope Ar50 were investigated by in-beam γ-ray spectroscopy following proton- and neutron-knockout, multinucleon removal, and proton inelastic scattering at the RIKEN Radioactive Isotope Beam Factory. The energies of the two previously reported transitions have been confirmed, and five additional states are presented for the first time, including a candidate for a 3- state. The level scheme built using γγ coincidences was compared to shell-model calculations in the sd-pf model space and to ab initio predictions based on chiral two- and three-nucleon interactions. Theoretical proton- and neutron-knockout cross sections suggest that two of the new transitions correspond to 2+ states, while the previously proposed 41+ state could also correspond to a 2+ state. ; We thank the RIKEN Nishina Center accelerator staff and the BigRIPS team for the stable operation of the high-intensity Zn beam and for the preparation of the secondary beam setting. This work has been supported by the JSPS Grant-in-Aid for Scientific Research JP16K05352, JP18K03639, JP16H02179, and JP18H05404, the RIKEN Special Postdoctoral Researcher Program, Colciencias–Convocatoria 617 Becas Doctorados Nacionales, the Ministry of Science and Technology of Vietnam through the Physics Development Program Grant No. ĐTĐLCN.25/18, HIC for FAIR, the Croatian Science Foundation under Projects No. 1257 and No. 7194, the European Regional Development Fund GINOP-2.3.3-15- 2016-00034 and the National Research, Development and Innovation Fund K128947 projects, the NKFIH (128072), the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P, the NRF Grants No. 2018R1A5A1025563 and No. 2019M7A1A1033186 funded by the Korean government, the MEXT as "Priority issue on post-K computer" (Elucidation of the fundamental laws and evolution of the universe), the Joint Institute for Computational Fundamental Science (JICFuS), the Ramón y Cajal program RYC-2017-22781 of the Spanish Ministry of Science, Innovation and Universities, the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Project-ID 279384907–SFB 1245 and Grant No. BL 1513/1-1, the PRISMA Cluster of Excellence, and the BMBF under Contracts No. 05P15RDFN1, No. 05P18RDFN1, and No. 05P19RDFN1. TRIUMF receives funding via a contribution through the National Research Council Canada. 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). The development of MINOS was supported by the European Research Council (ERC) through Grant No. MINOS-258567.

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).

7 pags. 4 figs. ; Fifty-five inclusive single nucleon-removal cross sections from medium mass neutron-rich nuclei impinging on a hydrogen target at ∼250 MeV/nucleon are measured at the RIKEN Radioactive Isotope Beam Factory. Systematically higher cross sections are found for proton removal from nuclei with an even number of protons as compared to odd-proton number projectiles for a given neutron separation energy. Neutron removal cross sections display no even-odd splitting, contrary to nuclear cascade model predictions. Both effects are understood through simple considerations of neutron separation energies and bound state level densities originating in pairing correlations in the daughter nuclei. These conclusions are supported by comparison with semimicroscopic model predictions, highlighting the enhanced role of low-lying level densities in nucleon-removal cross sections from loosely bound nuclei. ; We express our gratitude to the RIKEN Nishina Center accelerator staff for providing the stable and high-intensity uranium beam . A. O. thanks the European Research Council for its support through ERC Grant No. MINOS-258567, the Japanese Society for the Promotion of Science for the long-term fellowship L-13520, the German DFG SFB Grant No. 1245, and the Alexander von Humboldt Foundation. C. S. acknowledges support by the IPA program at the RIKEN Nishina Center. C. A. B. acknowledges support by U.S. Department of Energy Grant No. DE-FG02- 08ER41533 and U.S. National Science Foundation Grant No. 1415656. J. L. R.-S. acknowledges support by the Regional Government of Galicia under the program of postdoctoral fellowships. K. M. acknowledges support from German BMBF Grant No. 05P15PKFNA. M. L. C., M. L., and V. W. acknowledge support from German BMBF Grants No. 05P12RDFN8, No. 05P15RDFN1, and No. 05P12RDFN8, as well as DFG Grant No. SFB 1245. L. X. C. and B. D. L. are supported by the Vietnam MOST through Physics Development Program Grant No. ĐTĐLCN.25/18 and acknowledge the Radioactive Isotope Physics Laboratory of the RIKEN Nishina Center for supporting their stay during the experiment. A. J. and V. V. acknowledge support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2014-57196-C5-4-P. U.K. participants acknowledge support from the Science and Technology Facilities Council (STFC). Collaborators from I. M. P. were supported by the National Natural Science Foundation of China and the Chinese Academy of Sciences.

9 pags., 3 figs. ; The low-lying level structure of V63 was studied for the first time by the inelastic proton scattering and the proton knock-out reaction in inverse kinematics. The comparison of the newly observed γ-ray transitions at 696(8) keV and 889(16) keV with our shell-model calculations using the Lenzi-Nowacki-Poves-Sieja interaction established two excited states proposed to be the first 11/2- and 9/2- levels. The (p,p′) excitation cross sections were analyzed by the coupled channel formalism assuming pure quadrupole as well as quadrupole+hexadecapole deformations. This resulted in large deformation parameters placing V63 in the island of inversion located below Ni68. ; We are very grateful to the RIKEN Nishina Center accelerator staff for providing the stable beam and to the BigRIPS team for the smooth operation of the secondary beams. The development of the MINOS device has been supported by the European Research Council through the ERC Grant No. MINOS-258567. F.B. was supported by the RIKEN Special Postdoctoral Researcher Program. K.O. acknowledges the support by Grant-in-Aid for Scientific Research JP16K05352. Y.U. acknowledges the support by Grant-in-Aid for Scientific Research No. 20K03981. Y.L.S. acknowledges the support of Marie Skłodowska-Curie Individual Fellowship (H2020-MSCA-IF-2015-705023) from the European Union and the support from the Helmholtz International Center for FAIR. H.N.L. acknowledges the support from the Enhanced Eurotalents program (PCOFUND-GA-2013-600382) co-funded by CEA and the European Union. T.A., C.L., D.R., H.T., V.W., L.Z., H.N.L., V.W., and A.O. acknowledge the support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) Project No. 279384907-SFB 1245. R.B.G. acknowledges the support from the DFG under Grant No. BL 1513/1-1. Y.L.S. and A.O. acknowledge the support from the Alexander von Humboldt Foundation. B.D.L. and L.X.C. acknowledge the support from the Vietnam Ministry of Science and Technology under Grant No. ĐTCB.01/21/VKHKTHN. I.G. has been supported by HIC for FAIR and HRZZ under Projects No. 1257 and No. 7194. F.B. acknowledge the support from the RIKEN Special Postdoctoral Researcher Program. D.S. and Z.E. were supported by Projects No. GINOP-2.3.3-15-2016-00034 and K128947. V.V. acknowledges support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P. V.W. and P.K. acknowledge the support from BMBF Grants No. 05P15RDFN1 and No. 05P19RDFN1. P.K. acknowledges support from HGSHIRe. This work was also supported by NKFIH (114454) and by Swedish Research Council under Grants No. 621-2014-5558 and No. 2019-04880. 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). T.N. and Y.K. acknowledge the support by JSPS Grant-in-Aid for Scientific Research Grants No. JP16H02179, No. JP18H05404, and No. JP21H04465. ; Peer reviewed

8 pags., 4 figs., 3 tabs. ; The nuclear structure of 51Ar, an uncharted territory so far, was studied by the (p,2p) reaction using γ-ray spectroscopy for the bound states and the invariant mass method for the unbound states. Two peaks were detected in the γ-ray spectrum and six peaks were observed in the 50Ar+n relative energy spectrum. Comparing the results to our shell-model calculations, two bound and six unbound states were established. Three of the unbound states could only be placed tentatively due to the low number of counts in the relative energy spectrum of events associated with the decay through the first excited state of 50Ar. The low cross sections populating the two bound states of 51Ar could be interpreted as a clear signature for the presence of significant subshell closures at neutron numbers 32 and 34 in argon isotopes. It was also revealed that due to the two valence holes, unbound collective states coexist with individual-particle states in 51Ar. ; We are very grateful to the RIKEN Nishina Center accelerator staff for providing the stable beam and to the BigRIPS team for the smooth operation of the secondary beams. The development of the MINOS device has been supported by the European Research Council through the ERC Grant No. MINOS-258567. F. B. was supported by the RIKEN Special Postdoctoral Researcher Program. K. O. acknowledges the support by Grant-in-Aid for Scientific Research JP16K05352. Y. U. acknowledges the support by Grant-in-Aid for Scientific Research 20K03981. Y. L. S. acknowledges the support of Marie Skłodowska-Curie Individual Fellowship (H2020-MSCA-IF-2015-705023) from the European Union and the support from the Helmholtz International Center for FAIR. H. N. L. acknowledges the support from the Enhanced Eurotalents program (PCOFUND-GA-2013-600382) co-funded by CEA and the European Union. T. A., C. L., D. R., H. T., V. W., L. Z., H. N. L., V. W. and A. O. acknowledge the support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) Project No. 279384907-SFB 1245. R. B. G. acknowledges the support from the DFG under Grant No. BL 1513/1-1. Y. L. S. and A. O. acknowledge the support from the Alexander von Humboldt Foundation. B. D. L. and L. X. C. acknowledge the support from the Vietnam Ministry of Science and Technology under Grant No. ĐTCB.01/21/VKHKTHN. I. G. has been supported by HIC for FAIR and HRZZ under project No. 1257 and 7194. K. I. H., D. K. and S. Y. P. acknowledge the support from the NRF grant funded by the Korea government (No. 2017R1A2B2012382 and 2019M7A1A1033186). F. B. acknowledge the support from the RIKEN Special Postdoctoral Researcher Program. D. S. and Z. E. were supported by projects No. GINOP-2.3.3-15-2016-00034 and No. K128947. V. V. acknowledges support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P. V. W. and P. K. acknowledge the support from BMBF grants 05P15RDFN1 and 05P19RDFN1. P. K. acknowledges support from HGS-HIRe. This work was also supported by NKFIH (114454). ; Peer reviewed

7 pags., 3 figs. ; Direct proton-knockout reactions of ^{55}Sc at ∼220 MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei. ; Our gratitude is extended to the RIKEN Nishina Center accelerator staff for the stable and high-intensity transport of the Zn primary beam, and the BigRIPS team for their preparation of the magnetic settings of the secondary beam. F. B. is supported by the RIKEN Special Postdoctoral Researcher Program. S. C. acknowledges support from the IPA program at the RIKEN Nishina Center. K. O. and K. Y. acknowledge the support from Grants-in-Aid of the Japan Society for the Promotion of Science under Grants No. JP16K05352. This work was supported by JSPS KAKENHI Grants No. JP16H02179 and No. JP18H05404, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Grant No. BL 1513/1-1 HGS-HIRe and Project-ID 279384907-SFB 1245 and the GSI-TU Darmstadt cooperation agreement, the BMBF (Grant No. 05P19RDFN1), Swedish Research Council under Grants No. 621-2014-5558 and No. 2019-04880. L. X. C. and B. D. L. are supported by the Vietnam MOST via the Physics Development Program Grant No. TĐLCN.25/18. D. So. was supported by 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. L. S, 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). ; Peer reviewed

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 ; Peer reviewed