1943 · Lancaster PA:
"Pauli now applied the ?-limiting [lambda-limiting] process to meson theory, as he had announced in his communication to the New York meeting of the APS [American Physics Society] on 22-23 January 1943 . . . There he had observed that 'Such a weak coupling theory with point sources avoids all difficulties of the strong coupling theory with extended source'. The ensuing paper [this paper], submitted on 14 October 1943, starts with the simplest case of a neutral pseudoscalar meson field defined by the interaction, but without the index ? [alpha] and with ?? replaced by one. To be suitable for the application of the ?-limiting [lambda-limiting] process the formalism, to start with, has to be supplemented with some unphysical features." – Charles P. Enz, No Time to be Brief; a scientific autobiography of Wolfgang Pauli, Oxford, 2002, p. 379.
"The outbreak of World War II and the possible threat of Nazi persecution (Pauli's paternal grandparents were Jews) led him to accept a visiting professorship in 1940 at the Institute for Advanced Study in Princeton, N.J., U.S., where he worked mainly on meson theory. Although he became an American citizen in 1946, he went back to Europe that year, first to finally accept his 1945 Nobel Prize and then to return to his former position at ETH in Zürich." – Britannica.
Nelson H. F. Beebe, A Selected Bibliography of Publications by, and about, Wolfgang Pauli, 13 January 2015; Version 1.59, [Pau43a]. (Inventory #: S13098)