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Laser acceleration of ion beams
M.Chubaryan1, A.V. Prozorkevich2,
S.A. Smolyansky2 and I.A. Egorova2
1JINR,
Dubna
2Saratov 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.
But
• 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).
Surfing on plasmas
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 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.
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
A.V.Gaponov, M.A.Miller, JETPH,34,242 (1958)
• We will begin with consideration of a
principle of action of this force. Let us
consider a plane standing electro-magnetic
wave.
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 highfrequency 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.
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:
The nonrelativistic region
The relativistic region
The ultrarelativistic
region
is the
“average” of electric field
is the frequency of field
ion charge
ion mass
  eE
m
Parameter
as a function of
ion charge and mass for some
laser fields (Y.I.Salamin)