Speaker: Valery Serbo ( Novosibirsk State University)

Date: Wed May 16, 2001, 4.30 pm 
Location: Wean 7316

Title: High Energy Photon Colliders and Physics of gamma-gamma

Abstract: 

This talk is devoted to gamma-gamma collisions 
including methods of creating the colliding gamma-gamma  
beams and physical problems which can be studied in such collisions. 
A basic device for a gamma-gamma collider is a linear e+ e- collider. 
Unlike the situation in storage rings, in linear 
e+ e- colliders each bunch is used only once. This makes it 
possible to ``convert'' electrons into high-energy photons and to 
obtain colliding gamma-gamma and gamma-e beams. This idea 
was put forward by Novosibirsk group (Ginzburg, Kotkin, Serbo and 
Telnov) about twenty years ago and was further developed in details.
The required high-energy photons were suggested to be obtained by
Compton scattering of a laser light on the electron beams of 
colliders.

It is clear now that physics which can be studied at the gamma-gamma 
and gamma-e collideres is no less interesting than at e+ e- 
colliders. In the last years the Conceptual Projects of linear colliders
were published in US, Germany and Japan. Also, the Technical 
Design Project for the TESLA collider was prepared.  All these projects
include gamma-gamma options based on the scheme we proposed twenty
years ago. A progress in the development of linear colliders and 
high-power lasers make it possible to consider the photon colliders 
as a very interesting option for the nearest future.