Synopsis: Getting closer to the Bohr model

An algebraic version of Bohr’s collective model is shown to be an effective tool for the analysis of rotational and vibrational spectra in nuclei.
Synopsis figure

In the algebraic collective model, the five variables define the quadrupole moments of a nucleus. A group theoretical approach is used to separate the variables into a “radial” coordinate (β) and four angular variables. The radial wave functions can be chosen corresponding to a specific mean deformation in β while calculations involving the angular coordinates are made simple by group theoretical techniques. This leads to huge computational savings over calculations in a spherical basis (β=0), used in some previous models, for which a very much larger set of basis functions is required. The Bohr Hamiltonian can now be solved for virtually any assumed potential.

In a paper appearing in Physical Review C, David Rowe and Trevor Welsh of the University of Toronto in Canada and Mark Caprio of the University of Notre Dame in the US demonstrate the practical utility of the algebraic collective model when applied to various well-known solvable limits of the Bohr model. In several cases, they find a substantial amount of centrifugal stretching (elongation of the nucleus with increasing angular momentum), which is neglected in adiabatic approximations to the Bohr model.

They argue that, as in the case of the interacting boson model, the ease of carrying out collective model calculations for a wide range of Hamiltonians can be used to quickly characterize a large body of nuclear phenomena and test for limitations of the Bohr model. – John Millener


Announcements

More Announcements »

Subject Areas

Nuclear Physics

Previous Synopsis

Next Synopsis

Related Articles

Synopsis: Neutron Capture Constraints
Nuclear Physics

Synopsis: Neutron Capture Constraints

Experiments place tighter bounds on neutron capture rates that play an important role in the production of heavy elements in the Universe. Read More »

Synopsis: Trailing the Photons from Neutron Decay
Nuclear Physics

Synopsis: Trailing the Photons from Neutron Decay

A high-precision measurement of the photons emitted by neutron decays brings researchers closer to a new test of the standard model. Read More »

Synopsis: Fission Takes Its Time
Nuclear Physics

Synopsis: Fission Takes Its Time

Nuclear fission simulations show that the evolution of a splitting plutonium nucleus may be slower than previously thought. Read More »

More Articles