Conversation so far:
What was Luis Walter Alvarez earliest work?
At the Radiation Laboratory he worked with Lawrence's experimental team, which was supported by a group of theoretical physicists headed by Robert Oppenheimer.
Was Luis Walter Alvarez's earliest work successful?
Using magnets to sweep aside the positrons and electrons emanating from his radioactive sources, he designed a special purpose Geiger counter to detect only the soft X-rays coming from K capture.
Did Luis Walter Alvarez marry?
Yes, Geraldine Smithwick
Did Alvarez and Smithwich have any children?
They had two children, Walter and Jean.

Question: Did he invent anything ?
Self-contained rewrite: Did Luis Walter Alvarez invent anything ?