Older Than deck / Events and discoveries
Neutron
Discovered
1932
James Chadwick detected the particle with no electric charge in the atom’s nucleus.
Sources and checks
Checked 2026-11-01: Researched by Codex (two independent publishers, verbatim quotes); every counted quote re-found on its page by the server check (content-verify, or content-verify-pdf for PDFs); scope and plausibility reviewed by Claude (AI build agent). Quotes are short passages from each source; for dates the quote is the year as printed, read in context.
“Rutherford's researchers produced three major nuclear developments in 1932. In February, Chadwick announced the detection of the neutron.”American Institute of Physics — Rutherford’s Nuclear World: source, retrieved 2026-10-28; quote re-found by the server check
“discovered the neutron in 1932”University of Liverpool — oPAC historical biography: source, retrieved 2026-10-28; quote re-found by the server check
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