Claudio Pellegrini

Claudio Pellegrini (born in Rome on May 9, 1935) is an Italian physicist known for his pioneering work on X-ray free electron lasers and collective effects in relativistic particle beams. He was educated at the Sapienza University of Rome where he received the Laurea in Fisica summa cum laude in 1958 and the Libera Docenza, in 1965. From 1958 to 1978, he worked at the Laboratori Nazionali di Frascati for high energy and nuclear physics. In the early 1960s, he was at the Nordic Institute for Theoretical Physics (NORDITA) in Copenhagen, working on an alternative formulation of the theory of general relativity using tetrad fields to obtain, among other things, a better description of the energy-momentum complex. (See Teleparallelism for a summary of the theoretical context of this work.) In 1978, he moved to the United States and began work at Brookhaven National Laboratory, where he was an Associate Chairman of the National Synchrotron Light Source and co-director at the Center for Accelerator Physics. In 1989, he accepted an appointment at the University of California at Los Angeles (UCLA) as a professor of physics, and later became a Distinguished Professor.

At the Laboratori Nazionali di Frascati, he worked on the development of electron-positron colliders. He studied the physics of particle beams in accelerators, specifically instabilities and collective effects in high intensity particle beams resulting from the interaction of the particles with a self-generated electromagnetic field. In 1968 he discovered a novel collective effect, the Head-Tail-Instability, which limits the luminosity of a collider. The theory suggested a way to control the instability that has been applied to all colliders and storage rings, increasing the collider luminosity and extending their reach to explore elementary particle physics.

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