TY - JOUR

T1 - Dynamic Aperture of Synchrotron with Electron Cooling

AU - Popov, D. M.

AU - Vostrikov, V. A.

AU - Blinov, M. F.

N1 - This work was supported by ongoing institutional funding. No additional grants to carry out or direct this particular research were obtained. Публикация для корректировки.

PY - 2023/12

Y1 - 2023/12

N2 - The heavy ion facility for technological applications is developed at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. The booster synchrotron with electron cooling is one of the main parts of the facility. This work presents the beam dynamics simulation with betatron coupling and nonlinearities of the guided magnetic field. The transverse betatron coupling excited by electron cooling solenoid was compensated by the pair of skew quadrupole triplets with antisymmetric supply and located symmetrically relative to the solenoid center. The calculation of the vertical dispersion excited by the magnetic field of toroidal sections of the electron cooler was performed. The accelerator lattice was optimized for minimization of vertical dispersion. Another important factor of the beam dynamics is the tune dependence versus momentum deviation called chromaticity. To correct chromaticity, sextupole magnets are applied. On the other hand, sextupoles excite nonlinear resonances that can lead to significant limitation of the dynamic aperture. The dynamic aperture of the synchrotron was simulated by scanning of horizontal and vertical tunes in conditions of chromaticity and betatron coupling suppression. This method makes it possible to identify dangerous resonances. According to the calculations presented, a scheme with application of six sextupole families are developed. This scheme makes it possible to significantly reduce the influence of most dangerous resonances. The wide area of tunes with a fairly large dynamic aperture for particles with required momentum spread was found in simulations. Selection of the operating point in this particular area makes it possible to reduce the space charge effect on the dynamic aperture. At the chosen operating point, the influence of eddy currents and magnetic fields nonlinearities on the dynamic aperture was investigated.

AB - The heavy ion facility for technological applications is developed at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. The booster synchrotron with electron cooling is one of the main parts of the facility. This work presents the beam dynamics simulation with betatron coupling and nonlinearities of the guided magnetic field. The transverse betatron coupling excited by electron cooling solenoid was compensated by the pair of skew quadrupole triplets with antisymmetric supply and located symmetrically relative to the solenoid center. The calculation of the vertical dispersion excited by the magnetic field of toroidal sections of the electron cooler was performed. The accelerator lattice was optimized for minimization of vertical dispersion. Another important factor of the beam dynamics is the tune dependence versus momentum deviation called chromaticity. To correct chromaticity, sextupole magnets are applied. On the other hand, sextupoles excite nonlinear resonances that can lead to significant limitation of the dynamic aperture. The dynamic aperture of the synchrotron was simulated by scanning of horizontal and vertical tunes in conditions of chromaticity and betatron coupling suppression. This method makes it possible to identify dangerous resonances. According to the calculations presented, a scheme with application of six sextupole families are developed. This scheme makes it possible to significantly reduce the influence of most dangerous resonances. The wide area of tunes with a fairly large dynamic aperture for particles with required momentum spread was found in simulations. Selection of the operating point in this particular area makes it possible to reduce the space charge effect on the dynamic aperture. At the chosen operating point, the influence of eddy currents and magnetic fields nonlinearities on the dynamic aperture was investigated.

KW - dynamic aperture

KW - electron cooling

KW - synchrotron

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85186912797&origin=inward&txGid=3d0005bad622ee2543198809716a22e5

UR - https://www.mendeley.com/catalogue/c5228c8f-7c90-3475-945b-85e7a59b8350/

U2 - 10.1134/S1063778823110364

DO - 10.1134/S1063778823110364

M3 - Article

VL - 86

SP - 2446

EP - 2453

JO - Physics of Atomic Nuclei

JF - Physics of Atomic Nuclei

SN - 1063-7788

IS - 11

ER -