Abstract
We report the observation of a heavy particle , with mass GeV and width approximately zero. The observation was made from the reaction by measuring the mass spectrum with a precise pair spectrometer at the Brookhaven National Laboratory's 30-GeV alternating-gradient synchrotron.
- Received 12 November 1974
DOI:https://doi.org/10.1103/PhysRevLett.33.1404
©1974 American Physical Society
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Letters from the Past - A PRL Retrospective
2008 marked PRL’s 50th anniversary. As part of the celebrations a collection of milestone Letters was started. The collection contains Letters that have made long-lived contributions to physics, either by announcing significant discoveries, or by initiating new areas of research.
Focus
Landmarks—The Charming Debut of a New Quark
Published 26 February 2016
An unexpected particle discovery in 1974 was the first evidence for a fourth type of quark.
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