The Cosmotron

Early in the Laboratory's history, the consortium of universities responsible for founding the new research center, decided that Brookhaven should provide unique facilities for high energy physics research. In April 1948, the Atomic Energy Commission approved a plan for a proton synchrotron to be built at Brookhaven. The new machine would accelerate protons to previously unheard of energies, comparable to those of cosmic rays showering the earth's outer atmosphere. It would be called the Cosmotron.

The Cosmotron, 1949

There were accelerators before the Cosmotron, but this machine was the first accelerator in the world to send particles to energies in the billion electron volt, or GeV, region. The Cosmotron reached its full design energy of 3.3 GeV in January 1953.

Not only was the Cosmotron the world's highest energy accelerator, it was also the first synchrotron to provide an external beam of particles for experimentation outside the accelerator itself. Early on, the intensity of the beam extracted for experiments was ten billion protons per pulse. By 1966, intensity had been increased nearly 100 times.

The Cosmotron was the first machine to produce all the types of negative and positive mesons known to exist in cosmic rays, making possible the discoveries of the K0L meson and the first vector meson. It was also the first accelerator to produce heavy unstable particles, some of which were formerly called "V" particles, and this led directly to the experimental confirmation of the theory of associated production of strange particles.

After fourteen years of service to the physics research community, the Cosmotron ceased operation in 1966 and was dismantled in 1969. Knowledge gained from the Cosmotron would lead to revolutionary design improvements and pave the way for construction of Brookhaven's next big accelerator: the Alternating Gradient Synchrotron.

> Continue on to the Alternating Gradient Synchrotron...

Did you know?

T. D. Lee, of Columbia University, and C. N. Yang, then of Brookhaven, interpreted results of particle decay experiments at the Cosmotron which led to their 1957 Nobel Prize in Physics. More...

The Cosmotron was a 75-foot diameter machine, weighing 2,000 tons and composed of 288 C-shaped magnets, such as the one shown below, that guided the protons in a circular path.

Other Accelerators


Alternating Gradient Synchrotron

National Synchrotron Light Source

Relativistic Heavy Ion Collider