Interacting boson model

The interacting boson model (IBM) is a model in nuclear physics in which nucleons (protons or neutrons) pair up, essentially acting as a single particle with boson properties, with integral spin of 0, 2 or 4.

The IBM-I treats both types of nucleons the same and considers only pairs of nucleons coupled to total angular momentum 0 and 2, called respectively, s and d bosons. The IBM-II treats protons and neutrons separately.
History

This model was invented by Akito Arima and Francesco Iachello.
See also

Liquid drop model
Nuclear shell model

References

Arima, Iachello Collective nuclear states as representations of a SU(6) Group, Physical Review Letters 35, 1069–1072 (1975).
Arima, Iachello The interacting boson model, Cambridge University Press, 1987.
Arima, Iachello Interacting boson model of collective states, Part 1 (the vibrational limit) Annals of Physics 99, 253-317 (1976), Part 2 (the rotational limit) ibid. 111, 201-238 (1978), Part 3 (the transition from SU (5) to SU (3)), ibid. 115, 325-366 (1978), Part 4 (the O(6) limit) ibid. 123, 468-492 (1979).
Arima, Iachello The Interacting Boson Model, Annual Review of Nuclear and Particle Science 31, 75 (1981).
Talmi Simple Models of Complex Nuclei: The Shell Model and the Interacting Boson Model (1993) Harwood Academic Publishers

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