A History of Early High Energy Physics Research at UCL
Leonardo Castillejo was in the Department from 1950 as an Assistant Lecturer; he left in 1957 to work with Peierls at Birmingham, being replaced by Sigurd Zienau. In 1960, a second chair of physics was created and filled by Jim Hamilton, a former student of Massey's from Belfast. A small theory group formed under Hamilton, including A. Donnachie and W.S.Woolcock as lecturers, two RAs and seven research students. Hamilton left after a few years (1964 according to Fox, 1966 according to Colin Wilkin) and was replaced in 1967 by Castillejo. Donnachie left in 1966 (Fox says 1996, presumably a typo) and was replaced by Wilkin, who had obtained his PhD at Birmingham in 1963 with Mandelstam, then spent two years at CERN followed by 2 years at Brookhaven. Brian Martin also arrived in the theory group at this time. Fox refers to Zienau and others "moving over from the General Physics Theoretical Group" at this time.
Wilkin describes the theory group as having "worked very closely on data", although they did not work closely- with the experimentalists until much later. In Hamilton's time the group had worked on low energy pion-nuceon and pion-pion scattering, which Fox points out was "sponsored in part by ... the US Air Force".