Momentum Aperture without sextupole
Posted: 16 Jul 2018, 21:42
Dear All:
I want to tracking the Momentum Aperture for a lattice without sextupole to simulate the machine beam-tuning process.Without the sextupole,the chromaticity【dnux/dp (1/(2$gp$r)) = -2.159890e+02】and 【dnuy/dp (1/(2$gp$r)) = -2.921960e+02】 are so big!I used one particle tracking(by using the MALIGN element to set the initial DP),I get the particle with dp/p=0.013 could be survived for 10000 turns.But with the momentum_aperture command,I got that the deltaPositive is smaller than 4e-3,Particle lost with delta0 = -5.000000e-03.In the momentum_aperture command,I set forbid_resonance_crossing=0.
I used Accelerator Toolbox for the same lattice particle tracking,the particle with dp/p=0.013 could be survived for 10000 turns too!
I want to know the criterion for Particle lost in momentum_aperture command is same as track command?
Thanks in advance!
Tiansk
I want to tracking the Momentum Aperture for a lattice without sextupole to simulate the machine beam-tuning process.Without the sextupole,the chromaticity【dnux/dp (1/(2$gp$r)) = -2.159890e+02】and 【dnuy/dp (1/(2$gp$r)) = -2.921960e+02】 are so big!I used one particle tracking(by using the MALIGN element to set the initial DP),I get the particle with dp/p=0.013 could be survived for 10000 turns.But with the momentum_aperture command,I got that the deltaPositive is smaller than 4e-3,Particle lost with delta0 = -5.000000e-03.In the momentum_aperture command,I set forbid_resonance_crossing=0.
I used Accelerator Toolbox for the same lattice particle tracking,the particle with dp/p=0.013 could be survived for 10000 turns too!
I want to know the criterion for Particle lost in momentum_aperture command is same as track command?
Thanks in advance!
Tiansk