Perestroika and particle physics.

Perestrolka and particle physics 

For years Soviet physicists have talked about building powerful and innovative particle accelerators, but progress has been extremely slow. Now, according to a report in the January/February CERN COURIER, the new Soviet leadership has decided to push things. They are speeding up work on the Accelerator and Storage Complex, better known by its Russian acronym, UNK, and have decided to build a linear collider for electrons and positrons, called VLEPP.

UNK is planned to come in three stages. The first, now under construction, will provide beams of protons with 400 billion electron-volts energy (400 GeV) using conventional magnets to bend the path of the protons around a circle of 21 kilometers circumference. The second stage will use superconducting magnets to provide protons with 3 trillion electron-volts (3 TeV). If this stage is completed on schedule in 1993, UNK will have the world's most energetic protons for use in experiments with fixed targets. The third stage, due in 1995, will be a second 3-TeV beam to collide with the first.

Over the last decade or so, UNK planners have done a good deal of design work and have built and tested prototype magnets. Now actual groundwork has begun. At the Institute for High Energy Physics at Serpukhov, near Moscow, workers have so far cut 9 kilometers of the 21-km tunnel in which the accelerator will stand.

VLEPP will be a pair of linear accelerators, one for electrons, one for positrons, arranged so that the particles that come out of them will collide with each other. At 500 GeV for each arm, VLEPP seems likely to be the world's first big linear collider.

Up to now Soviet physicists have concentrated their electron-positron colliding beam work at Novosibirsk, where the late Gersh Budker pioneered the conception and construction of such equipment. However, VLEPP will be built at Serpukhov, so as to give the opportunity for eventually building connections to UNK and obtaining high-energy electron-proton and positron-proton collisions.