Laser acceleration of ion beams M.Chubaryan 1, A.V. Prozorkevich 2, S.A. Smolyansky 2 and I.A. Egorova 2 1 JINR, Dubna 2 Saratov State University

Introduction The most powerful particle accelerator, is under construction at CERN, that is 8.6-kilometer-diameter LHC. The collisions of its two seven-trillion-volt proton beams should tell us what gives particles their mass. To provide high energy by linear accelerator is very expensive and need a great construction. Recently scientists consider new methods of the particle acceleration by the laser radiation. Therefore, we want examine possibility of the acceleration of the nucleus (from He to Au). But

Surfing on plasmas The process works in this way: A pulse from an intense laser creates a disturbance in the plasma. The beam creating a region of excess positive charge and a region of excess negative charge and forming an electron bubble around the positive region. This region inside bubble pulls the negatively charged electrons back. J.Chandrashekar Scientific American, may [05], 2006 J.M. Dawson from the University of California, Los Angeles first proposed this general method in 1979.

The bubble regime The disturbance forms a wave of the Coulomb field that travels through the plasma with the bubble at nearly the speed of light and accelerates any charged particles that come under its influence. Experiments have been taking place recently gave good results. Problem: The realization of similarly process for positive ions is not developed.

The methods of acceleration with using of the gradient force We will begin with consideration of a principle of action of this force. Let us consider a plane standing electro-magnetic wave. A.V.Gaponov, M.A.Miller, JETPH,34,242 (1958) The plane electro-magnetic wave potential Since particles move aside the reduction of potential then as time goes by they gather in units. In each point gradient force has a cross-section and longitudinal component. But the longitudinal component in the sum gives zero. Hence the gradient force operates only with a cross-section direction and it does not bring the contribution to the longitudinal acceleration.

Acceleration by means of high- frequency moving knots. Using fluctuations with various frequencies it is possible to carry out the accelerated movement of potential holes and, hence, to make accelerations of the particles localized in holes. Movement of knot occurs at change of frequency of one of lasers

Because of cross-section heterogeneous fields an intensive laser beam can push out particles from the field It occurs when frequency of a wave is much larger then own frequency of a particle. Using it, it is possible to accelerate particles: 1. By the front of the ultra short laser impulse. 2. By the moving laser focus The focus motion is carried out by changing of a focal length at time.

Is the theory relativistic or nonrelativistic? The basic parameter of the theory (the adiabatic parameter) allows to select the characteristic regions: is the “average” of electric field is the frequency of field ion mass ion charge The nonrelativistic region The relativistic region The ultrarelativistic region

Parameter as a function of ion charge and mass for some laser fields (Y.I.Salamin)