A joint Fermilab/SLAC publication

The J/Psi particle original papers

05/16/08

J/Psi data

On November 10, 1974, SLAC's Burton Richter and colleagues found evidence for a particle they called the Ψ (the Greek letter Psi). Meanwhile on the east coast of the United States, Samuel Ting and his colleagues found comparable evidence for a particle they called the J. Both were the same particle and papers from both groups were published in Physical Review Letters on 2 December, 1974, as the first evidence for what is now known as the J/Ψ. Richter and Ting were jointly awarded the Nobel Prize in Physics in 1976 for the discovery, a mere two years after the work was done.

As part of PRL's 50-year anniversary, the American Physical Society has now made those papers freely accessible to everybody. You can read both the Richter and colleagues, and Ting and colleagues papers via this introductory page. Back in September 2005, we published a reproduction plot of Richter's logbook with the original data for the Ψ particle in symmetry.

Latest news articles
03/23/17
Wired

The Hetdex dark energy experiment is different.

03/23/17
Science

Physicists are searching for a hypothetical "dark sector": an entire shadow realm of hidden particles.

03/16/17
CERN

The LHCb collaboration announced the discovery of a new system of five particles all in a single analysis

03/16/17
Science

Dianna Cowern—a.k.a. Physics Girl—has one of those invent-it-yourself jobs that exist only in the age of the internet.