12 research outputs found
Simulation of Quasi-Adiabatic Beam Capture into Acceleration at the Nuclotron
No full textThe routine RF system being used at the Nuclotron allows one to inject the beam at ramping magnetic field with following acceleration at constant amplitude of accelerating voltage. At these conditions at least a half of the particles circulating in the vacuum chamber after injection is not captured in longitudinal acceptance. At the same time vacuum chamber sizes permit to extend the momentum spread of the beam enough to make gymnastic with it inside the stable zone of longitudinal phase space on the flat magnetic field at injection. A quasi-adiabatic capture was considered for increasing the Nuclotron beam intensity. Simulation of such a kind of process with subsequent acceleration was performed. It was shown that in this case it is possible to capture and accelerate up to 100 % of the injected beam
General harmonic measures for distance-expanding dynamical systems
Get PDFPartially motivated by the study of I. Binder, N. Makarov, and S. Smirnov
[BMS03] on dimension spectra of polynomial Cantor sets, we initiate the
investigation on some general harmonic measures, inspired by Sullivan's
dictionary, for distance-expanding dynamical systems. Let be
an open distance-expanding map on a compact metric space . A Gromov
hyperbolic tile graph associated to the dynamical system is
constructed following the ideas from M. Bonk, D. Meyer [BM17] and P.
Ha\"issinsky, K. M. Pilgrim [HP09]. We consider a class of one-sided random
walks associated with on . They induce a Martin boundary of the
tile graph, which may be different from the hyperbolic boundary. We show that
the Martin boundary of such a random walk admits a surjection to . We
provide a class of examples to show that the surjection may not be a
homeomorphism. Such random walks also induce measures on called harmonic
measures. When is a visual metric, we establish an equality between the
fractal dimension of the harmonic measure and the asymptotic quantities of the
random walk.Comment: 44 page
CONCEPTUAL DESIGN OF A 240 MeV SUPERFERRIC SEPARATED ORBIT CYCLOTRON *
No full textAbstract A conceptual design of the Separated Orbit Cyclotron (SOC) for the proton energy of 240 MeV based on the use of superferric magnets (dipoles and quadrupoles) is presented. Superconducting RF cavities are used as well. The beam intensity is determined by, but not limited to the 500µA available from the IBA "Cyclone-30" cyclotron to be used as the 30MeV injector. The electrical power draw of the helium refrigerator is 250kW
