From 1987 to 1991 the largest construction project in the Soviet Union was neither a new hydroelectric station nor an oil pipeline. It was the world’s largest proton synchrotron accelerator in Protvino, a small science town about a hundred kilometers south of Moscow. The twenty-one-kilometer-long underground tunnel ring with a diameter of five meters (comparable to the circle line of the Moscow metro) had already been excavated, and people were working around the clock to assemble the massive vacuum chamber with large bending and focusing superconducting magnets, each six meters long and weighing many tons. A special factory had been built in Serpukhov, a nearby industrial city, to manufacture the two thousand magnets needed for the accelerator. The world’s largest helium liquefying plant, designed to generate thirty thousand liters of liquid helium per hour, was also under construction. Liquid helium was required to keep the temperature in the giant vacuum chamber as close to absolute zero as possible.
The accelerator (known as UNK, from the Russian term for acceleration storage complex) was expected to begin fixed target experiments in 1993. It belonged to the Institute of High Energy Physics, part of the research network of the Soviet military- industrial nuclear empire, commonly known as Minsredmash (short for the USSR Ministry of Medium Machinery). Soviet atomic scientists had never had to consider costs, even when they rose to billions of rubles. Protvino had already become famous among particle physicists because its previous proton accelerator, one kilometer long and with an acceleration energy of seventy-six billion electron-volts (76 GeV), had also been the largest in the world when it was commissioned in 1967. A higher particle energy (four hundred GeV) was only achieved in 1972, when a larger synchrotron, seven kilometers in length, was built by the U.S. National Accelerator Laboratory in Illinois.