Thomas Ypsilantis coauthored the 1955 identification of the antiproton. Selecting a negative particle's momentum was insufficient because lighter negative particles were much more abundant. Measuring its speed as well supplied a mass test. The experiment combined magnetic selection, timed scintillation signals and velocity-sensitive Cherenkov detectors, connecting complementary measurements to a particle identity rather than relying on negative electric charge alone.[ref]
The early antiproton work by Owen Chamberlain. 1959 authored account, 1955 coauthor list and momentum/velocity discrimination
A physicist.[ref]
https://physicstoday.aip.org/obituaries/thomas-john-ypsilantis. Independent professional profile
Portrait of Thomas John Ypsilantis
. Articles by others on the same topic
Thomas Ypsilantis (1790–1848) was a prominent figure in the Greek War of Independence against Ottoman rule. He belonged to the Ypsilantis family, a notable Phanariot family in the Ottoman Empire, and played a pivotal role in the efforts to liberate Greece. Ypsilantis was educated in Europe and influenced by the ideals of the Enlightenment and the Greek desire for independence.