Zero Gradient Synchrotron

The Zero Gradient Sychrotron (ZGS), was a weak focussing 12.5 GeV proton accelerator that operated at the Argonne National Laboratory in Illinois from 1964 to 1979.

It enabled pioneering experiments in particle physics, in the areas of

• quark model tests;
• neutrino physics (observation of neutrino interaction in its 12ft hydrogen bubble chamber for the first time in 1970);
• spin physics of hadrons (utilizing a polarized accelerated proton beam in the GeV range for the first time); and
• Kaon decays.

Other noteworthy features of the ZGS program were the large number of university-based users and the pioneering development of large superconducting magnets for bubble chambers and beam transport.

The hardware and building of the ZGS were ultimately inherited by a spallation neutron source program, the Intense Pulsed Neutron Source (IPNS).

References

• Symposium on the 30th Anniversary of the ZGS Startup, Malcolm Derrick (ed), ANL-HEP-CP-96-12, 1994.
• History of the ZGS, J. Day et al. (eds), AIP Conference Proceedings 60, AIP, New York, 1980, ISBN 0883181592 .