skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Measurement of E2 transition strengths in {sup 32,34}Mg

Abstract

The degree of collectivity in the neutron-rich nuclei {sup 32}Mg and {sup 34}Mg has been determined via intermediate-energy Coulomb excitation in inverse kinematics. Measured energies of the first excited 2{sup +} states and reduced electric quadrupole transition probabilities B(E2;0{sub g.s.}{sup +}{yields}2{sub 1}{sup +}) are presented for {sup 32}Mg and {sup 34}Mg. The results agree with previous measurements and confirm the placement of both nuclei within the ''island of inversion.''.

Authors:
; ; ; ; ; ;  [1];  [2]; ; ; ;  [1];  [3];  [4]
  1. National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)
  2. (United States)
  3. Physics Division, Argonne National Laboratory, Argonne, Illinosis 60439 (United States)
  4. Department of Physics and Astronomy, Ursinus College, Collegeville, Pennsylvania 19426 (United States)
Publication Date:
OSTI Identifier:
20699125
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 72; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevC.72.054320; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COULOMB EXCITATION; E2-TRANSITIONS; HEAVY ION REACTIONS; MAGNESIUM 32; MAGNESIUM 34; NEUTRON-RICH ISOTOPES; NUCLEAR ELECTRIC MOMENTS; OSCILLATOR STRENGTHS; PARITY; PROBABILITY; SPIN

Citation Formats

Church, J.A., Campbell, C.M., Dinca, D.-C., Glasmacher, T., Olliver, H., Perry, B.C., Yurkewicz, K.L., Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, Enders, J., Gade, A., Hu, Z., Mueller, W.F., Janssens, R.V.F., and Riley, L.A. Measurement of E2 transition strengths in {sup 32,34}Mg. United States: N. p., 2005. Web. doi:10.1103/PhysRevC.72.054320.
Church, J.A., Campbell, C.M., Dinca, D.-C., Glasmacher, T., Olliver, H., Perry, B.C., Yurkewicz, K.L., Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, Enders, J., Gade, A., Hu, Z., Mueller, W.F., Janssens, R.V.F., & Riley, L.A. Measurement of E2 transition strengths in {sup 32,34}Mg. United States. doi:10.1103/PhysRevC.72.054320.
Church, J.A., Campbell, C.M., Dinca, D.-C., Glasmacher, T., Olliver, H., Perry, B.C., Yurkewicz, K.L., Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, Enders, J., Gade, A., Hu, Z., Mueller, W.F., Janssens, R.V.F., and Riley, L.A. Tue . "Measurement of E2 transition strengths in {sup 32,34}Mg". United States. doi:10.1103/PhysRevC.72.054320.
@article{osti_20699125,
title = {Measurement of E2 transition strengths in {sup 32,34}Mg},
author = {Church, J.A. and Campbell, C.M. and Dinca, D.-C. and Glasmacher, T. and Olliver, H. and Perry, B.C. and Yurkewicz, K.L. and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 and Enders, J. and Gade, A. and Hu, Z. and Mueller, W.F. and Janssens, R.V.F. and Riley, L.A.},
abstractNote = {The degree of collectivity in the neutron-rich nuclei {sup 32}Mg and {sup 34}Mg has been determined via intermediate-energy Coulomb excitation in inverse kinematics. Measured energies of the first excited 2{sup +} states and reduced electric quadrupole transition probabilities B(E2;0{sub g.s.}{sup +}{yields}2{sub 1}{sup +}) are presented for {sup 32}Mg and {sup 34}Mg. The results agree with previous measurements and confirm the placement of both nuclei within the ''island of inversion.''.},
doi = {10.1103/PhysRevC.72.054320},
journal = {Physical Review. C, Nuclear Physics},
number = 5,
volume = 72,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
  • The X(5) symmetry describes nuclei at the critical point of the shape phase transition from axially deformed rotor nuclei to spherical vibrators. {sup 150}Nd, {sup 152}Sm, and {sup 154}Gd were the first nuclei where the predicted characteristics of the X(5) symmetry were observed. Later it was shown that also {sup 176,178,180}Os can be successfully described with the X(5) symmetry.In the close vicinity of shape phase transitions one expects strongly changing nuclear shapes. In the X(5) region around A = 150 this was observed for nuclei with different neutron numbers, whereas in the X(5) region around A = 180 this ismore » to be expected for different proton numbers. The aim of the work presented here is the confirmation of a rapid shape change for nuclei close to {sup 178}Os. Besides the knowledge on the level scheme of the nuclei of interest, especially absolute E2 transition strengths are crucial for the interpretation of nuclear structure. Prolate deformation is expected for {sup 176}W. Thus we performed a recoil distance Doppler shift (RDDS) measurement on {sup 176}W to measure E2 transition strengths from level lifetimes. The experiment was performed at the Cologne FN TANDEM accelerator with the Cologne coincidence plunger with the reaction {sup 169}Dy({sup 16}O,4n){sup 176}W and a beam energy of 80 MeV. We will present our experimental results and relate them to data on the neighboring nuclei {sup 178}Os and {sup 182}Pt. The results will be discussed in the framework of nuclear shape transitions in this mass region and compared to calculations with both the Interacting Boson Model (IBM) and the GCM.« less
  • Excitation functions are reported for total fusion near and below the Coulomb barrier of the systems /sup 32,34/S+/sup 24,25,26/Mg and /sup 27/Al. The data cannot be reproduced by one-dimensional barrier penetration calculations. The enhancement of the cross sections at low energies is compared to predictions of models taking into acount the static deformation or zero point vibration of the reaction partners. Calculations including zero point motion do not reproduce the observed variations of the measured cross sections with respect to the neutron number of target and projectile. Reasonable agreement is obtained when calculating fusion between statically deformed nuclei. Finally, themore » fusion process is described in a quantum mechanical coupled channels model, indicating the importance of dynamical effect on sub-barrier fusion.« less