Alpha clustering in $^{28}$Si probed through the identification of   high-lying $0^+$ states
  Aspects of nuclear structure in alpha-conjugate nuclei have long been associated with alpha clustering, including the existence of superdeformed bands. In this paper, an alpha-particle inelastic scattering experiment investigating the location of $0^+$ states in $^{28}$Si is reported in an attempt to locate possible cluster states. The results are compared to a semi-microscopic model which shows good agreement with the data, and supports the assignment of a newly discovered $0^+$ state as the band-head of a previously observed superdeformed band in $^{28}$Si 
P. Adsley, D.G. Jenkins, J. Cseh, S.S. Dimitriova, J.W. Br\"ummer,   K.C.W. Li, D.J. Mar\'in-L\'ambarri, K. Lukyanov, N.Y. K...
nucl-ex nucl-th