from 1953 to 1955 at the University of Manchester, under Patrick Blackett, Nobel Prize winner of Physics, and then as an associate researcher in the European Organization for Nuclear Research (CERN), in Geneva, Switzerland, from 1955 to 1963.
In 1963, Salmeron returned to Brazil and accepted a post as professor of physics in the newly created Universidade de BrasÃlia.
Unfortunately, the military dictatorship repressed strongly the faculty with liberal and leftist ideas and he joined 223 other professors in protest, who resigned from the University in October 1965.
In 1966 Salmeron left definitely Brazil and went to work in Europe at CERN again, where he had an important role in experiments attempting to discover the quark–gluon plasma.
Afterwards (1967) he worked at the École Polytechnique in Paris, France, one of the most important schools of engineering in the world.