New local optics measurements and correction techniques for the LHC and its luminosity upgrade
As the beams at the interaction points (IPs) of circular colliders are pushed toward smaller sizes, the correction of the magnetic field errors in high-β regions become increasingly important, but also challenging. This paper presents an algorithm developed to compute automatically local corrections...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2020-04-01
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| Series: | Physical Review Accelerators and Beams |
| Online Access: | http://doi.org/10.1103/PhysRevAccelBeams.23.041001 |
| _version_ | 1819158680718802944 |
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| author | J. Coello de Portugal R. Tomás M. Hofer |
| author_facet | J. Coello de Portugal R. Tomás M. Hofer |
| author_sort | J. Coello de Portugal |
| collection | DOAJ |
| description | As the beams at the interaction points (IPs) of circular colliders are pushed toward smaller sizes, the correction of the magnetic field errors in high-β regions become increasingly important, but also challenging. This paper presents an algorithm developed to compute automatically local corrections. This algorithm has been successfully used in the LHC and in simulations of the HL-LHC to establish tolerances for the magnetic errors. The limitations of the current β^{*} measurement technique (K-modulation) are studied, together with alternative techniques for β^{*} control: computing the minimum β near the IP using the betatron phase measured with new instrumentation and locating the beam waist via luminosity scans. This push toward smaller beam sizes also requires large β-functions in the arcs that enhance local errors currently negligible. Experimental results of a way of correcting this new type of local errors using orbit bumps in sextupoles is also presented. These studies forecast a drastic change in the LHC commissioning strategy to be applied in the HL-LHC for needing luminosity measurements in intermediate stages. |
| first_indexed | 2024-12-22T16:28:31Z |
| format | Article |
| id | doaj.art-9144d61d32b3448bb4b1eb2f64d87749 |
| institution | Directory Open Access Journal |
| issn | 2469-9888 |
| language | English |
| last_indexed | 2024-12-22T16:28:31Z |
| publishDate | 2020-04-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review Accelerators and Beams |
| spelling | doaj.art-9144d61d32b3448bb4b1eb2f64d877492022-12-21T18:20:07ZengAmerican Physical SocietyPhysical Review Accelerators and Beams2469-98882020-04-0123404100110.1103/PhysRevAccelBeams.23.041001New local optics measurements and correction techniques for the LHC and its luminosity upgradeJ. Coello de PortugalR. TomásM. HoferAs the beams at the interaction points (IPs) of circular colliders are pushed toward smaller sizes, the correction of the magnetic field errors in high-β regions become increasingly important, but also challenging. This paper presents an algorithm developed to compute automatically local corrections. This algorithm has been successfully used in the LHC and in simulations of the HL-LHC to establish tolerances for the magnetic errors. The limitations of the current β^{*} measurement technique (K-modulation) are studied, together with alternative techniques for β^{*} control: computing the minimum β near the IP using the betatron phase measured with new instrumentation and locating the beam waist via luminosity scans. This push toward smaller beam sizes also requires large β-functions in the arcs that enhance local errors currently negligible. Experimental results of a way of correcting this new type of local errors using orbit bumps in sextupoles is also presented. These studies forecast a drastic change in the LHC commissioning strategy to be applied in the HL-LHC for needing luminosity measurements in intermediate stages.http://doi.org/10.1103/PhysRevAccelBeams.23.041001 |
| spellingShingle | J. Coello de Portugal R. Tomás M. Hofer New local optics measurements and correction techniques for the LHC and its luminosity upgrade Physical Review Accelerators and Beams |
| title | New local optics measurements and correction techniques for the LHC and its luminosity upgrade |
| title_full | New local optics measurements and correction techniques for the LHC and its luminosity upgrade |
| title_fullStr | New local optics measurements and correction techniques for the LHC and its luminosity upgrade |
| title_full_unstemmed | New local optics measurements and correction techniques for the LHC and its luminosity upgrade |
| title_short | New local optics measurements and correction techniques for the LHC and its luminosity upgrade |
| title_sort | new local optics measurements and correction techniques for the lhc and its luminosity upgrade |
| url | http://doi.org/10.1103/PhysRevAccelBeams.23.041001 |
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