Download - Do we have an Aperture Kicker for the LHC?
April 10, 2007 LHCCWG - Frank Schmidt, ABP 1
Do we have an Aperture Kicker for Do we have an Aperture Kicker for the LHC?the LHC?
- Kicker Hardware
- Kick Classification
- Examples
- DA at Injection and Collision
- Conclusion
April 10, 2007 LHCCWG - Frank Schmidt, ABP 6
Kick Classification Kick Classification
Basic Optics
MKQ
≤ 2 Tune, Phase Advance, Linear Coupling, Beta-beat…
Detailed Optics
AC-Dipole, MKA
2 – 6 Beta-beat, Non-Linear Optics, Corrections
Dynamic Aperture
MKA, AC-Dipole
≥ 6 Stable & Chaotic Motion, Particle Loss, Lifetime
April 10, 2007 LHCCWG - Frank Schmidt, ABP 7
Linear Coupling (SPS)Linear Coupling (SPS)
R. TomR. Tomás et al.ás et al.
Linear coupling compensation and tracking data at all BPMs to compare the machine model to the data
Linear coupling can be treated as any other resonance
April 10, 2007 LHCCWG - Frank Schmidt, ABP 8
Missing Sextupoles (SPS)Missing Sextupoles (SPS)
(F. Schmidt, R. Tomas et al.)(F. Schmidt, R. Tomas et al.)
Specially arranged SPS configuration for extraction sextupoles
+ + + + - - - -
(3,0) resonance driving terms
Data fully decohered (factor 2 correction applied)
Comparison with nominal model
One extraction sextupole accidentally disconnect
Before
After
April 10, 2007 LHCCWG - Frank Schmidt, ABP 9
Uncompensated Skew Sextupole Resonance Uncompensated Skew Sextupole Resonance (PSBooster) (PSBooster) (P. Ursch(P. Urschüütz, M. Benedikt)tz, M. Benedikt)
CERN PS data
vertical plane
3Qy = 16
and
(0, -2) spectral line
Uncorrected machine
vertical motion
beam losses
phase space
FFT
April 10, 2007 LHCCWG - Frank Schmidt, ABP 10
Corrected Skew Sextupole Resonance Corrected Skew Sextupole Resonance (PSBooster) (PSBooster) (P. Ursch(P. Urschüütz, M. Benedikt)tz, M. Benedikt)
CERN PS data
vertical plane
3Qy = 16
and
(0, -2) spectral line
Resonance compensated with skew sextupoles
Setting based on the reduction of the (0, -2)
line amplitude
vertical motion
beam losses
phase space
FFT
April 10, 2007 LHCCWG - Frank Schmidt, ABP 11
Dynamic Aperture SPS 1988/89Dynamic Aperture SPS 1988/89 Gareyte, Hilaire, Schmidt et al.Gareyte, Hilaire, Schmidt et al.
April 10, 2007 LHCCWG - Frank Schmidt, ABP 12
DA at Injection and CollisionDA at Injection and Collision
MKQ MKA
AC-
Dipole
DA DA-BB
Injection 1.62 5 16 11 7
Collision 0.41 1.4 4 9-15 5.5
April 10, 2007 LHCCWG - Frank Schmidt, ABP 13
ConclusionConclusion
• Except for may be the AC-dipole at Injection the answer to the original question is:
NO, we do not have an Aperture Kicker!!
• BUT: If we are really courageous we can upgrade the MKA from 890V to 4kV
Injection: 22.5 Collision: 6.3 • No hardware upgrade except: