The invention relates to an isokinetic gantry arrangement for the isocentric
guidance of a particle beam (12), that can be rotated about a horizontal
longitudinal axis (16) and has a beam optical system, symbolized by magnets
(36, 38, 40), that deflects the particle beam (12) axially infected
by a particle beam accelerator, radially and vertically relative to the horizontal
longitudinal axis (16), with a largely rotationally-symmetrical primary
structure (18) and a secondary structure (30) that holds the magnets
(36, 38, 40) and is supported by the primary structure (18), with
the secondary structure (30) having a rigidity that is designed so that
the vertical displacements of the magnets (36, 38, 40) due to their weight
are essentially of equal magnitude (isokinetic) in all the angle of rotation positions
of the gantry arrangement (10), and a method for its design.
