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This workshop presentation discusses the search for octupole deformed actinium isotopes using resonance ionization spectroscopy. It explores the nuclear shapes and deformations, as well as the hyperfine structure and magnetic dipole moments of these isotopes.
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Search for Octupole Deformed Actinium Isotopes using Resonance IonizationSpectroscopy Elise Verstraelen, Workshop “Physics between lead and uranium”, 18-04-2019
Nuclear shapes Z = 28 Z = 20 N= 28 Z = 8 Z = 2 N= 20 N= 8 N= 2 L. Gaffney, Presentation: Nuclear shape phenomena in heavy nuclei, March 2014 Z = 82 Z = 50 N =126 Proton number(Z) N = 82 N = 50 Neutron number (N)
Nuclear shapes Octupole deformation Z = 34 Z = 28 Z = 20 N= 34 N= 28 Z = 8 Z = 2 N= 20 N= 8 N= 2 L. Gaffney, Presentation: Nuclear shape phenomena in heavy nuclei, March 2014 I. Budinčević, Nuclear structure studies of rare francium isotopes using CRIS, PhD Thesis, KU Leuven, September 2015 Z = 88 Z = 82 Z = 56 Z = 50 N = 134 N =126 N = 88 Proton number(Z) N = 82 N= 56 N = 50 Neutron number (N)
Nuclear shapes Octupole deformation Z = 34 Z = 28 Z = 20 N= 34 N= 28 Z = 8 Z = 2 N= 20 N= 8 N= 2 L. Gaffney, Presentation: Nuclear shape phenomena in heavy nuclei, March 2014 I. Budinčević, Nuclear structure studies of rare francium isotopes using CRIS, PhD Thesis, KU Leuven, September 2015 Z = 88 Z = 82 Z = 56 Z = 50 N = 134 N =126 N = 88 Proton number(Z) N = 82 N= 56 N = 50 Neutron number (N)
Nuclearshapes Octupole deformation 224Ra 220Rn Static octupole deformation Octupolevibrations Z = 34 Z = 28 Z = 20 N= 34 N= 28 Z = 8 Z = 2 N= 20 N= 8 N= 2 L. Gaffney, Presentation: Nuclear shape phenomena in heavy nuclei, March 2014 L.P. Gaffney et al., Nature 497, 199 (2013) Z = 88 Z = 82 Z = 56 Z = 50 N = 134 N =126 N = 88 Proton number(Z) N = 82 N= 56 N = 50 Neutron number (N)
Isotope shift Atomic transitions are isotope (isomer) dependent
Changes in mean-square charge radius and deformation B.A. Marsh, Nature Physics (2018),
Changes in mean-square charge radius and deformation B.A. Marsh, Nature Physics (2018),
Hyperfine structure 227Ac
Hyperfine structure 227Ac
Hyperfine structure 227Ac
Hyperfine structure 227Ac
Hyperfine structure Magnetic dipole splitting μ μ 227Ac
Experiments Johannes Gutenberg Universität (Mainz) 225,227Ac: In-source laser spectroscopy High resolution (FWHM ~ 150 MHz) The comparison of the measured center of gravities and the A-parameters of 225,227Ac with this high-resolution data set was used to identify systematic uncertainties on the deduced TRIUMF - and A values. ISOL facility ISAC (TRIUMF) 225-229Ac: In-source laser spectroscopy Low resolution (FWHM ~ 5 GHz) A. Teigemhöfer, Isotope shift and hyperfine structure measurements on silver, actinium and astatine by in-source resonant ionization spectroscopy, PhD Thesis, University of Manitoba, 2016 227Ac REFERENCE
Odd-even staggering Inverted odd-even staggering Normal odd-even staggering 0.2 fm2 220Rn 224Ra
Comparison to mean-field calulations By S. Goriely and W. Ryssens
Comparison to mean-field calulations By S. Goriely and W. Ryssens
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model ~ 3 G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model ~ 3 227Ac Parity doublets G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits What is the magnetic dipole moment of a Nilsson level? Nilsson model G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? 225,227,229Ac (I=3/2) Small quadrupole deformation? is independent of the projection Ω gl=glfree and gs=0.6gsfree G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988). R. Neugart and G. Neyens, The Euroschool Lectures on Physics with Exotic Beams, Vol. II , edited by J. Al-Khaliliand E. Roeckl, Lecture Notes in Physics, Vol. 700 (Springer Berlin Heidelberg, 2006) pp. 135-89.
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Small quadrupole deformation? Large quadrupole deformation? is independent of the projection Ω dependents on the projection Ω G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Large quadrupole deformation? dependents on the projection Ω 225,227,229Ac (I=3/2) gR=0.4 and 0.25 for odd Z and odd N, respectively Rotational g-factor Single-particle intrinsic g-factor G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Large quadrupole deformation? dependents on the projection Ω 225,227,229Ac (I=3/2) Rotational g-factor Single-particle intrinsic g-factor G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Large quadrupole deformation? dependents on the projection Ω 225,227,229Ac (I=3/2) Rotational g-factor Single-particle intrinsic g-factor G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Large quadrupole deformation? dependents on the projection Ω 225,227,229Ac (I=3/2) Rotational g-factor Single-particle intrinsic g-factor G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Fingerprints of octupole deformation Inverted odd-even staggering
Fingerprints of octupole deformation Inverted odd-even staggering EDF calculations
Fingerprints of octupole deformation Inverted odd-even staggering EDF calculations Magnetic dipole moments
Thank you for your attention! This work has been performed in collaboration with E . Verstraelen1, A. Teigelhöfer2,3, F. Ames2,3, A. Barzakh4, M. Bender5, R. Ferrer1, S. Goriely1,6, C. Granados1,7, P.-H. Heenen8, R. Heinke9, M. Huyse1, Yu. Kudryavtsev1, P. Kunz2,3, J. Lassen2,3, V. Manea1, S. Raeder10,11, W. Ryssens12, S. Sels1,7, P. Van den Bergh1, P. Van Duppen1, K. Wendt9, A. Zadvornaya1,13, and The LISOL Collaboration 1KU Leuven, Leuven, Belgium 2TRIUMF, Canada’s National Laboratory for Particle and Nuclear Physics, Canada 3University of Manitoba, Canada 4Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, 188300 Gatchina, Russia 5IPNL, Universitéde Lyon, UniversitéLyon 1, CNRS/IN2P3, F-69622 Villeurbanne, France 6Institut d'Astronomie et d'Astrophysique, CP229, Universite Libre de Bruxelles, B-1050 Bruxelles, Belgium 7CERN, CH-1211 Geneve 23, Switzerland 8PNTPM, CP229, UniversitéLibre de Bruxelles, B-1050 Bruxelles, Belgium 9Johannes Gutenberg-Universität, Mainz, Germany 10Helmholtz Institut Mainz, Mainz, Germany 11GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany 12Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520 13Department of Physics, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
Experiments LISOL facility (Louvain-La-Neuve) 212,213Ac: In-gas-cell laser spectroscopy 214,215Ac: In-gas-jet laser spectroscopy High resolution (FWHM ~ 400 MHz) Low resolution (FWHM ~ 6 GHz) Excimer-pumped dye laser system Resonanceionization in supersonic gas jets: High-resolutionis obtainedbyreducingboth Doppler- andpressurebroadeningduetothe low T and conditions in the gas jet. R. Ferrer et al., Nature Communications 8, 14520 (2017) Yu. Kudryavtsev et al., NIM B 267 (2009) 2908–2917 215Ac
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? Large quadrupole deformation? 227Ra (I=3/2) dependents on the projection Ω 227Ac (I=3/2) 228Ac (I=3) gR=0.4 G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).
Magnetic dipole moments Sensitivity to single-particle orbits Nilsson model What is the magnetic dipole moment of a Nilsson level? 225Ra (I=1/2) Large quadrupole deformation? dependents on the projection Ω 227Ac (I=3/2) 226Ac (I=1) gR=0.4 G. A. Leander and Y. S. Chen, Physical Review C 37,2744 (1988).