Nuclear Physics in Comparison: Cesar Lattes and Physicists from the Northern Hemisphere, 1930s-1940s

Between 1946 and 1948, Brazilian physicist Cesar Lattes played a central role in the experimental observation of mesons. After earning his bachelor's degree from the University of Sao Paulo, Lattes developed specific skills sets in nuclear physics, and later handled instruments at laboratories associated with the University of Bristol and the University of California, Berkeley. This article analyzes records produced by scientists from these laboratories during their studies of nuclei, and compares their practices and values. It gives special attention to the non-verbal experimental knowledge that Lattes developed and promoted, which was essential for creating instrumental sets and identifying visual evidence of the existence of mesons. Throughout this work, Lattes adapted easily to laboratories and extracted the most he possibly could from available instruments and theories.