Advanced

Interplay of Touschek Scattering, Intrabeam Scattering, and RF Cavities in Ultralow-emittance Storage Rings

Leemann, Simon LU (2014) 5th International Particle Accelerator Conference (IPAC 2014) In Proceedings of IPAC’14 p.1612-1614
Abstract
When it goes into operation in 2016, the MAX IV 3 GeV storage ring will be the first ultralow-emittance storage ring based on a multibend achromat lattice. Such ultralow-emittance rings make use of a large number of weak bending magnets which leads to low radiation losses in the dipoles compared to power radiated from insertion devices. Therefore, the emittance in such rings depends strongly on the insertion devices and gap settings. The large stored current along with the low transverse emittance lead to strong intrabeam scattering which blows up the beam's 6D emittance. The Touschek lifetime depends on the 6D emittance: it grows with increasing longitudinal emittance which makes bunch lengthening cavities attractive. On the other hand,... (More)
When it goes into operation in 2016, the MAX IV 3 GeV storage ring will be the first ultralow-emittance storage ring based on a multibend achromat lattice. Such ultralow-emittance rings make use of a large number of weak bending magnets which leads to low radiation losses in the dipoles compared to power radiated from insertion devices. Therefore, the emittance in such rings depends strongly on the insertion devices and gap settings. The large stored current along with the low transverse emittance lead to strong intrabeam scattering which blows up the beam's 6D emittance. The Touschek lifetime depends on the 6D emittance: it grows with increasing longitudinal emittance which makes bunch lengthening cavities attractive. On the other hand, in the ultralow-emittance regime, reducing the transverse emittance actually increases the Touschek lifetime. Damping wigglers and insertion devices reduce the transverse emittance, but they can also increase the Touschek lifetime by reducing the available cavity overvoltage and thus increasing the bunch length. Using the MAX IV 3 GeV storage ring as an example, this paper demonstrates the intricate interplay between transverse emittance (insertion devices, emittance coupling), longitudinal emittance (tuning of main cavities as well as harmonic cavities), and choice of stored current in an ultralow-emittance ring as well as its implications for brightness optimization. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
in
Proceedings of IPAC’14
pages
3 pages
publisher
IPAC 2014
conference name
5th International Particle Accelerator Conference (IPAC 2014)
ISBN
978-3-95450-132-8
language
English
LU publication?
yes
id
0455083a-cc2b-46d8-b1d9-172b88dccbcd (old id 4538939)
alternative location
http://accelconf.web.cern.ch/AccelConf/IPAC2014/papers/tupri025.pdf
date added to LUP
2014-07-18 09:54:26
date last changed
2016-07-12 13:42:14
@inproceedings{0455083a-cc2b-46d8-b1d9-172b88dccbcd,
  abstract     = {When it goes into operation in 2016, the MAX IV 3 GeV storage ring will be the first ultralow-emittance storage ring based on a multibend achromat lattice. Such ultralow-emittance rings make use of a large number of weak bending magnets which leads to low radiation losses in the dipoles compared to power radiated from insertion devices. Therefore, the emittance in such rings depends strongly on the insertion devices and gap settings. The large stored current along with the low transverse emittance lead to strong intrabeam scattering which blows up the beam's 6D emittance. The Touschek lifetime depends on the 6D emittance: it grows with increasing longitudinal emittance which makes bunch lengthening cavities attractive. On the other hand, in the ultralow-emittance regime, reducing the transverse emittance actually increases the Touschek lifetime. Damping wigglers and insertion devices reduce the transverse emittance, but they can also increase the Touschek lifetime by reducing the available cavity overvoltage and thus increasing the bunch length. Using the MAX IV 3 GeV storage ring as an example, this paper demonstrates the intricate interplay between transverse emittance (insertion devices, emittance coupling), longitudinal emittance (tuning of main cavities as well as harmonic cavities), and choice of stored current in an ultralow-emittance ring as well as its implications for brightness optimization.},
  author       = {Leemann, Simon},
  booktitle    = {Proceedings of IPAC’14},
  isbn         = {978-3-95450-132-8},
  language     = {eng},
  pages        = {1612--1614},
  publisher    = {IPAC 2014},
  title        = {Interplay of Touschek Scattering, Intrabeam Scattering, and RF Cavities in Ultralow-emittance Storage Rings},
  year         = {2014},
}