BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:New High-spin states in W-182 DTSTART;VALUE=DATE-TIME:20260520T084500Z DTEND;VALUE=DATE-TIME:20260520T090500Z DTSTAMP;VALUE=DATE-TIME:20260624T101350Z UID:indico-contribution-649-3827@indico.tlabs.ac.za DESCRIPTION:Speakers: Lefika Maphage (iThemba LABS/UCT)\nThis work present s a detailed investigation of high-spin states in $^{182}$W\, populated th rough a deep-inelastic reaction using an 840 MeV $^{136}$Xe beam on a thic k $^{186}$W target and studied using coincidence $\\gamma$-ray spectroscop y. Out-of-beam data were used to extend the known level scheme\, confirmin g the $K^{\\pi}$ = 16$^{+}$ rotational band up to the 19$^{+}$ state and i dentifying new levels feeding this structure. The study is motivated by th e need to understand how nuclear structure evolves at high angular momentu m. Several new intrinsic states have been observed up to 6549 keV\, includ ing an isomeric state with a lifetime of 148(9) ns. Spin and parity assign ments were derived from transition multipolarities using internal conversi on coefficients\, angular correlation and mixing ratios\, with most states firmly characterized\, including the 6549 keV state assigned $K^{\\pi}$ = 24$^{-}$.\n\nNo new rotational bands were observed\, indicating a dominan ce of intrinsic configurations at high spin. Configuration assignments\, s upported by multi-quasiparticle calculations\, led to the identification o f several six-quasiparticle states with transition strengths consistent wi th neighboring nuclei in the A $\\approx$ 180 region. At high $K$-values\, weak transitions intensities limited the full characterization of some st ates\, however\, the long lifetime of the $K^{\\pi}$ = 24$^{-}$ isomer is suggested to arise from configuration changes rather than $K$-forbidden de cay\, while $K^{\\pi}$ = 20$^{+}$ isomer shows behavior consistent with $K $-isomerism. Overall\, this work provides insight into the increasing domi nance of intrinsic structure over collective motion at high-spin in $^{182 }$W.\n\nhttps://indico.tlabs.ac.za/event/139/contributions/3827/ LOCATION:NRF-iThemba LABS\, Old Faure Road\, Cape Town Auditorium URL:https://indico.tlabs.ac.za/event/139/contributions/3827/ END:VEVENT BEGIN:VEVENT SUMMARY:Bridging Reaction Physics and Nuclear Structure: γ-Ray Spectrosco py and Cross-Section Systematics for Nucleon-Induced Reactions DTSTART;VALUE=DATE-TIME:20260520T082500Z DTEND;VALUE=DATE-TIME:20260520T084500Z DTSTAMP;VALUE=DATE-TIME:20260624T101350Z UID:indico-contribution-649-3836@indico.tlabs.ac.za DESCRIPTION:Speakers: Walid Yahia Cherif (Nuclear research center of Algie rs (CRNA))\nWe present here a a comprehensive and systematic study of nucl ear γ-ray production cross-sections induced by proton reactions on a seri es of key nuclei\, specifically 24\,25\,26Mg\, 28\,29\,30Si\, 40Ca\, and 5 6Fe [1\,2]. These investigations are conducted within the framework of an Algeria-France-South Africa collaboration at the iThemba LABS facility\, u tilizing the high-resolution AFRODITE gamma-ray spectrometer. The primary objective is to provide high-precision experimental data in a proton energ y range of 30-200 MeV [1\,3] where existing data are often scarce or incon sistent\, yet crucial for multiple scientific domains.\nThe measured cross -sections serve as a cornerstone for several applications. In medical phys ics\, they are essential for optimizing radioisotope production and improv ing dose calculations in proton therapy. In nuclear astrophysics\, these d ata are employed to simulate γ-ray line emissions resulting from the inte raction of galactic cosmic rays (GCRs) with abundant elements in the inter stellar medium (ISM) and solar flares. By comparing laboratory measurement s with satellite observations (such as those from INTEGRAL or COMPTEL)\, w e can better determine the chemical composition and understand the energet ic processes of the cosmos.\nA central technical aspect of this work invol ves the adjustment of optical model potential (OMP) parameters for nucleon -nucleus interactions. Beyond the primary gamma-ray line analyses followi ng inelastic scattering on target nuclei\, our analysis allows for the mea surement of production cross-sections for a wide range of residual nuclei. Indeed\, the complex interaction mechanisms lead to the observation of va rious isotopes resulting from nucleon or alpha emission\, such as 21\,22Ne \, 22\,23Na\, and 24\,25\,26Al from magnesium and silicon targets\, as wel l as 38\,39K\, 36\,38Ar\, 54\,55Fe\, and 52Cr for heavier targets. To ensu re the highest accuracy\, the analysis of the γ-ray spectra is complement ed\, whenever necessary and possible\, by a lineshape calculation to accou nt for Doppler effects and peak broadening.\nThis process is a fundamental approach to better understand the physics of reactions and the complex in teractions between the candidates (incident particles and target nuclei). By systematically adjusting the OMP parameters\, we can adjust the nuclear level coupling and determine the nuclear deformation parameters (β2​ a nd β4​). While the analysis of the 40Ca data is currently in progress-f ocusing on the optimization of nucleon-induced reactions and their implica tions for residual Argon nuclei-future objectives aim to extend this metho dology to α-particle induced reactions as they are rather scarce. Ultimat ely\, this hierarchical approach - moving from fundamental interaction phy sics to the adjustment of theoretical models - is needed for improving the predictive accuracy of global nuclear reaction codes such as TALYS.\nThe experimental and theoretical results obtained and compiled will be present ed and discussed.\n\nReferences:\n[1] W. Yahia-Cherif\, et al. (2020). Mea surement and analysis of nuclear γ-ray production cross sections in proto n interactions with Mg\, Si\, and Fe nuclei abundant in astrophysical site s over the incident energy range Ep​=30-66 MeV. Phys. Rev. C\, 102(2)\, 025802. DOI: 10.1103/PhysRevC.102.025802\n[2] W. Yahia-Cherif (2025). Opti cal model potential parameter optimization for nucleon-induced reactions o n 40Ca: Implications on γ-ray production cross sections for residual Argo n nuclei. EPJ Web of Conferences\, 322\, 05004. DOI: 10.1051/epjconf/20253 2205004\n[3] Y. Rahma\, W. Yahia-Cherif\, et al. (2023). γ-ray emission i n proton-induced nuclear reactions on natC and Mylar targets over the inci dent energy range Ep​=30-200 MeV. Astrophysical implications. Nucl. Phys . A\, 1032\, 122622. DOI: 10.1016/j.nuclphysa.2023.122622\n\nhttps://indic o.tlabs.ac.za/event/139/contributions/3836/ LOCATION:NRF-iThemba LABS\, Old Faure Road\, Cape Town Auditorium URL:https://indico.tlabs.ac.za/event/139/contributions/3836/ END:VEVENT BEGIN:VEVENT SUMMARY:Electric monopole (E0) studies at iThemba LABS DTSTART;VALUE=DATE-TIME:20260520T080000Z DTEND;VALUE=DATE-TIME:20260520T082500Z DTSTAMP;VALUE=DATE-TIME:20260624T101350Z UID:indico-contribution-649-3802@indico.tlabs.ac.za DESCRIPTION:Speakers: Maluba Vernon J. Chisapi (iThemba LABS/Stellenbosch University)\nElectric monopole (E0) transition studies focus on nuclear tr ansitions between states of the same spin and parity (typically $0^{+}\\ri ghtarrow 0^{+}$)\, which are critical for probing nuclear structure\, shap e coexistence\, and deformation. The E0 strengths ($\\rho ^{2}(E0)$) are key parameters to understanding nuclear shape mixing and isomerism in vari ous nuclei\, including light\, odd-A\, and shape-coexistence in nuclei.\nB ecause single-photon emission is forbidden\, these transitions are measure d via internal conversion electrons (ICE) or electron-positron pair format ion (IPF)\, serving as a sensitive indicator of changes in the mean-square d charge radius. \nAs such\, high-precision electron spectrometers (e.g.\, Si(Li) detectors) and detector arrays consisting of HPGe and LaBr3:Ce de tectors are used to measure internal conversion coefficients (ICC) to iden tify E0 components. \n iThemba LABS has\, in the last 5 to 10 years\, been developing spectrometers suited for E0 transition studies. This talk will focus on the in-house refurbishment of the existing solenoid magnetic len s into an electron and internal-pairs spectrometer\, the in-beam experimen t involving 30 MeV proton beam on a $^{50}$Ti target aimed at investigatin g the excited 0$^{+}_{2}$ state in $^{50}$Ti\, as well as future experime ntal possibilities\, for example when this facility will be used in conjun ction with other existing spectrometers like the K600.\n\nhttps://indico.t labs.ac.za/event/139/contributions/3802/ LOCATION:NRF-iThemba LABS\, Old Faure Road\, Cape Town Auditorium URL:https://indico.tlabs.ac.za/event/139/contributions/3802/ END:VEVENT BEGIN:VEVENT SUMMARY:Shape coexistence in neutron deficient nuclei DTSTART;VALUE=DATE-TIME:20260520T073000Z DTEND;VALUE=DATE-TIME:20260520T080000Z DTSTAMP;VALUE=DATE-TIME:20260624T101350Z UID:indico-contribution-649-3831@indico.tlabs.ac.za DESCRIPTION:Speakers: Philippos Papadakis (STFC Daresbury Laboratory)\nAcr oss the nuclear chart\, many interesting and diverse phenomena arise throu gh the interplay of single-particle motion\, nucleon pairing and collectiv ity. One such phenomenon\, known as shape coexistence\, is defined as the presence of distinct nuclear shapes within the same nucleus and at similar energy [1]. Significant theoretical and experimental effort is taking pla ce to explore this phenomenon in different mass regions\, while it is sugg ested that it could manifest in most\, if not all nuclei [2].\n\nOne of th e more prominent regions where shape coexistence has been observed\, is in neutron-deficient nuclei close to the neutron mid-shell at N=104 and the Z=82 magic number. A broad range of experimental approaches including lase r spectroscopy\, α-decay fine structure measurements\, in-beam γ-ray and conversion electron spectroscopy\, lifetime measurements and Coulomb exci tation experiments have been employed to study this phenomenon in detail.\ n\nIn this presentation\, we will explore some of these techniques\, focus ing primarily on simultaneous in-beam γ-ray and conversion electron spect roscopy [3]\, that has been instrumental in recent years in the study of s hape coexistence in lead nuclei [4-8]. To demonstrate its effectiveness we will discuss some of the latest findings in particular in even-even lead isotopes.\n\n[1] P. Garrett\, M. Zielinska and E. Clément\, Prog. Part. a nd Nucl. Phys. 124\, 103931 (2022).\n[2] K. Heyde and J.L. Wood\, Review o f Mod. Phys. 83\, 1467 (2011).\n[3] J. Pakarinen et al.\, Eur. Phys. J A 5 0\, 53 (2014).\n[4] J. Ojala et al.\, Communication Physics 5:213 (2022).\ n[5] P. Papadakis et al.\, Phys. Lett. B 858\, 139048 (2024).\n[6] A.M. Pl aza et al.\, Communication Physics 8:8 (2025).\n[7] J. Ojala et al.\, Phys . Lett. B 867\, 139601 (2025).\n[8] A.M. Plaza et al.\, Phys. Lett. B 870\ , 139906 (2025).\n\nhttps://indico.tlabs.ac.za/event/139/contributions/383 1/ LOCATION:NRF-iThemba LABS\, Old Faure Road\, Cape Town Auditorium URL:https://indico.tlabs.ac.za/event/139/contributions/3831/ END:VEVENT END:VCALENDAR