Non-linear Beam Dynamics Studies for JLEIC Electron Collider Ring

Slides:



Advertisements
Similar presentations
The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme.
Advertisements

Dynamic Aperture Study for the Ion Ring Lattice Options Min-Huey Wang, Yuri Nosochkov MEIC Collaboration Meeting Fall 2015 Jefferson Lab, Newport News,
Optimization of Field Error Tolerances for Triplet Quadrupoles of the HL-LHC Lattice V3.01 Option 4444 Yuri Nosochkov Y. Cai, M-H. Wang (SLAC) S. Fartoukh,
Present MEIC IR Design Status Vasiliy Morozov, Yaroslav Derbenev MEIC Detector and IR Design Mini-Workshop, October 31, 2011.
1 BROOKHAVEN SCIENCE ASSOCIATES 1 NSLS-II Lattice Design 1.TBA-24 Lattice Design - Advantages and shortcomings Low emittance -> high chromaticity -> small.
Optics with Large Momentum Acceptance for Higgs Factory Yunhai Cai SLAC National Accelerator Laboratory Future Circular Collider Kick-off Meeting, February.
First evaluation of Dynamic Aperture at injection for FCC-hh
Optimization of the Collider rings’ optics
JLEIC Electron Collider Ring Design and Polarization
JLEIC simulations status April 3rd, 2017
NSLS-II Lattice Design Strategies Weiming Guo 07/10/08
Optimization of Triplet Field Quality in Collision
Large Booster and Collider Ring
CEPC pretzel scheme study
First Look at Nonlinear Dynamics in the Electron Collider Ring
Optics Development for HE-LHC
Optimization of CEPC Dynamic Aperture
Electron collider ring Chromaticity Compensation and dynamic aperture
Nonlinear Dynamics and Error Study of the MEIC Ion Collider Ring
Error and Multipole Sensitivity Study for the Ion Collider Ring
DA Study for the CEPC Partial Double Ring Scheme
Progress of SPPC lattice design
XII SuperB Project Workshop LAPP, Annecy, France, March 16-19, 2010
Collider Ring Optics & Related Issues
Ion Collider Ring Chromatic Compensation and Dynamic Aperture
Yuri Nosochkov Yunhai Cai, Fanglei Lin, Vasiliy Morozov
Multipole Limit Survey of FFQ and Large-beta Dipole
JLEIC Collider Rings’ Geometry Options
Progress on Non-linear Beam Dynamic Study
Feasibility of Reusing PEP-II Hardware for MEIC Electron Ring
Fanglei Lin, Andrew Hutton, Vasiliy S. Morozov, Yuhong Zhang
Update on MEIC Nonlinear Dynamics Work
Update on MEIC Nonlinear Dynamics Work
Ion Collider Ring Using Superferric Magnets
Fanglei Lin, Yuhong Zhang JLEIC R&D Meeting, March 10, 2016
Alternative Ion Injector Design
Update on study of chromaticity correction schemes for ion ring
Ion ring lattice with -I sextupole pairs for ir chromaticity correction Y. Nosochkov, M-H. Wang
First Look at Error Sensitivity in MEIC
Fanglei Lin, Yuri Nosochkov Vasiliy Morozov, Yuhong Zhang, Guohui Wei
Update on JLEIC Electron Ring Design
Multipole Limit Survey of FFQ and Large-beta Dipole
G. Wei, V.S. Morozov, Fanglei Lin
G.H. Wei, V.S. Morozov, Fanglei Lin Y. Nosochkov, M-H. Wang (SLAC)
Fanglei Lin MEIC R&D Meeting, JLab, July 16, 2015
Compensation of Detector Solenoids
G.H. Wei, V.S. Morozov, Fanglei Lin Y. Nosochkov (SLAC), M-H. Wang
Update on MEIC Nonlinear Dynamics Work
JLEIC Collider Rings’ Geometry Options (II)
Progress Update on the Electron Polarization Study in the JLEIC
Multipole Limit Survey of Large-beta Dipoles
Integration of Detector Solenoid into the JLEIC ion collider ring
G. Wei, V.S. Morozov, Fanglei Lin MEIC R&D Meeting, JLab, Oct 27, 2015
Status of IR / Nonlinear Dynamics Studies
Possibility of MEIC Arc Cell Using PEP-II Dipole
More on MEIC Beam Synchronization
JLEIC Electron Ring Nonlinear Dynamics Work Plan
Upgrade on Compensation of Detector Solenoid effects
Update on MEIC Nonlinear Dynamics Work
Fanglei Lin JLEIC R&D Meeting, August 4, 2016
MEIC R&D Meeting, JLab, August 20, 2014
Summary of JLEIC Electron Ring Nonlinear Dynamics Studies
Chromaticity correction in e-ring with TME cells and –I sextupole pairs in arcs Y. Nosochkov 28 February 2017.
MEIC beam path change with e-ring bypass lines
Update on MEIC Nonlinear Dynamics Work
DYNAMIC APERTURE OF JLEIC ELECTRON COLLIDER
A TME-like Lattice for DA Studies
Error Sensitivity in MEIC
Update on DA Studies for a TME-like Lattice
Update for ion ring lattice chromaticity correction
Presentation transcript:

Non-linear Beam Dynamics Studies for JLEIC Electron Collider Ring Fanglei Lin, Vasiliy Morozov, Guohui Wei, Yuhong Zhang (JLAB) Yunhai Cai, Yuri Nosochkov (SLAC) Min-Huey Wang JLEIC Collaboration Meeting Spring 2017 April 3-5, 2017 F. Lin

Outline The goal of the study is to identify the lattice design of the electron collider ring with the best overall properties: low emittance, adequate chromatic correction and large dynamic aperture (DA) Optimized baseline design based on FODO arc cells and PEP-II magnets Recap of chromaticity compensation and update on DA Design based on TME-like arc cells and new magnets Chromaticity compensation and DA Design based on short FODO arc cells and new magnets Conclusions and Outlook

Recap of the Optimized Baseline Design PEP-II type FODO arc cells and PEP-II magnets Circumference: C = 2185.54 m = 2 x 811.84 m arcs + 2 x 280.92 m straights Natural chromaticity: [xH, xV] = [-113, -120] Optimized for minimum emittance Emittance at 5 GeV (from Elegant) without chromaticity correction blocks (CCB) Before optimization: ge = 138 mm-rad, e = 14 nm-rad After optimization: ge = 92 mm-rad, e = 9.5 nm-rad (8.9 nm-rad from MAD) Complete ring without non-linear chromaticity correction blocks IP, b*=10/2cm

Chromatic Sextupoles – Optimized Baseline Linear chromaticity correction: conventional 2-family sextupoles in 108o arc cells (30 cells with sextupoles per arc  compensation of high order effects due to ~2p phase advance in every 10 cells) Non-linear correction: Chromaticity Correction Blocks (CCB) on each side of IP, where sextupoles are set nearly in phase with the FFQ for correction of non-linear chromaticity e- R=155m RF Spin rotator Arc, 261.7 81.7 Forward e- detection IP Tune trombone & Straight FODOs Future 2nd IP CCB Arc sextupoles Future CCB for 2nd IP

CCB Schemes FODO type CCB, ex = 19.4 nm SBCC (scheme-6), ex = 8.3 nm Interleaved –I sextupole pairs in regular FODO arc cells  no impact on emittance, but strong sextupoles, residual non-linear effects, insufficient correction, small off-energy DA Compact CCB with 3 interleaved sextupoles  adequate chromaticity correction, but residual non-linear effects, small DA, large emittance (~15 nm-rad @ 5 GeV) FODO type CCB with non-interleaved –I sextupoles pairs and high b finctions  adequate chromaticity correction and DA, but large emittance (>15 nm-rad) SuperB type CCB (SBCC) with non-interleaved –I sextupole pairs and missing dipoles  adequate correction and DA, lowest 8.3 nm-rad emittance (with short dipoles) ‒ Best -I S2 S1 FODO type CCB, ex = 19.4 nm SBCC (scheme-6), ex = 8.3 nm

Correction and DA Update – Optimized Baseline Best SBCC option with short dipoles (scheme-6), ex = 8.3 nm-rad @ 5 GeV Tune vs Dp/p b* vs Dp/p Qx = 48.22 Qy = 50.16 No errors: DA = ±23sx×72sy (LEGO) PEP-2 MP field errors (except FFQ): DA = ±20sx×46sy 10 seeds Dp/p=0

Summary – Optimized Baseline Design Chromaticity Correction Schemes x/x,0 DA: x/σx , y/σy Range of (p/p)/σ p/p=0 p/p=0.4% Linear correction: conventional 2-family arc sextupoles (v1) Non-linear: no dedicated correction 1 ±20, ±48 0, 0   9 Linear correction: conventional 2-family arc sextupoles Non-linear: interleaved –I sext pairs in regular arc cells (v1a) Non-linear: FODO type CCB with 2 non-interleaved –I sextupole pairs, optimized phase advance (v1b3) 2.1 ±15, ±40 ±4.5, ±10   9 Non-linear: FODO type CCB with 2 non-interleaved –I sextupole pairs, optimized phase advance, reduced beta functions for lower emittance (v1d2) 1.7 ±17, ±41 ±5, ±10 Non-linear: compact CCB with 3 interleaved sextupoles, optimized phase advance ±8.5, ±18 ±5, ±7.3 Non-linear: SuperB type scheme (SBCC) with regular length dipoles and large bending angles (scheme-3 ) 1.4 ±25, ±60 ±10, ±15 Non-linear: SBCC with short dipoles and small bending angles (scheme-6, optimized, ring geometry not yet matched) 0.93 ±23, ±72 ±7, ±26 11 Best option

Work Plan – since 2016 Fall Meeting Optimize SBCC for low emittance in the optimized baseline design ‒ Done Can emittance be further reduced? Implement the SBCC in the low emittance design with TME-like arc cells and new magnets; match ring’s geometry; optimize chromaticity correction; check dynamic aperture If DA is good, continue with studies in bullet # 4 Otherwise  study the low emittance design with short FODO-arc-cell and new magnets; optimize chromaticity correction; check dynamic aperture Further studies Replace thin-lens trombones with quadrupole adjustment, verify performance Tune scan to find optimal tune for maximum DA Effects of misalignment and field errors on DA Implement orbit correction scheme (BPMs and correctors) Specify tolerances Effects of non-linear field errors on DA Regular magnets: start with the PEP-II specs FF quads: specify tolerances Next  bullet # 2: study performance of ring design based on TME arc cells

Design Based on TME Arc Cells Matched geometry, C = 2276.58 m = 2 x 925.18 m arcs + 2 x 213.11 m straights Low emittance TME-like arc cells with new magnets Low emittance SBCC scheme Two options studied: 4 high-b SBCCs or 2 high-b + 2 low-b SBCCs Emittance @ 5 GeV: e = 3.2 nm-rad, ge = 30.9 mm-rad without SBCCs, e = 3.0 nm-rad, ge = 29.4 mm-rad with 4 high-b SBCCs IP SBCC Design with 4 high-b SBCCs Design with 2 high-b + 2 low-b SBCCs

Arc Cell and SBCC – TME Design SD,SF,SF,SD TME-like arc cell with new magnets Length 22.8 m (same as ion ring arc cell) Arc bending radius 155.45 m (as in the baseline) Phase advance 270o / 90o (x/y) 4 dipoles Length 4 m, bending angle 2.1o Field 0.37 T @ 12 GeV Sagitta 1.83 cm 4 quadrupoles Length 0.56 m Gradient 24 T/m @ 12 GeV 4 sextupoles (2 families) Arc IP S1 S2 Low emittance SBCC (high-b) Short dipoles with small bending angles  low H-function  low emittance contribution Two non-interleaved –I sextupole pairs per SBCC with sufficiently high beta functions Optimized phase advance (np + Dm) from SBCC sextupoles to FFQs for best correction of non-linear chromaticity

Chromaticity Correction – TME design Non-linear correction: previously designed low emittance SBCC 4 high-b SBBCs ‒ for nominal IP and future 2nd IP 2 high-b SBCCs (near IP) + 2 low-b SBCCs ‒ lower natural chromaticity Linear correction (in arcs): Conventional 2-family sextupoles in 24 TME cells per arc (non-linear compensation properties due to ~2p phase advance in every 4 cells ) -I sextupole pairs (non-interleaved or interleaved); various options as shown in the table X, Y indicate X or Y sextupoles in a given cell; empty cells have no sextupoles 90o between same family pairs to cancel 1st order chromatic beta Sextupole strengths of “1” and “2” families in scheme 3d are fixed at X1 = X2/2 and Y1 = Y2/2 Cell # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 3a X Y 3b 3c 3d X1 X2 Y1 Y2 3e 3f

Correction Performance and DA – TME design Schemes with –I pairs in arcs require strong arc sextupoles Large local chromatic beta variation in arcs leading to non-linear chromaticity and poor correction with insufficient momentum range Best performance with: Conventional 2-family arc sextupoles ‒ lowest sextupole strengths and chromatic non-linearities 2 high-b SBCCs (to correct FFQ) + 2 low-b SBCCs ‒ lowest natural chromaticity Tune vs Dp/p 15σx 29σy Dynamic aperture w/o errors Qx = 65.22 Qy = 35.16 Dynamic aperture is smaller than in the optimized baseline design

Short Summary – TME Design Chromaticity Compensation Schemes Arc Sexts K2 (1/m3) x , x DA: x/σx , y/σy (p/p)/σ =0 =0.4% Linear correction: conventional 2-family arc sextupoles Non-linear: 4 high-b SBCCs – 2 SBCCs for FFQ correction, 2 other SBCCs not used for correction 14.71, -22.92 -159, -196 -9, +5 Non-linear: 4 high-b SBCCs – all used for correction 13.93, -22.04 8.8, 23 7, 12 -12, +12 Linear correction: conventional 2-family arc sextupoles, but different position of focusing sextupoles in TME cell Non-linear: 4 high-b SBCCs – 2 SBCCs for FFQ correction, 2 other SBCCs for local correction 43.81, -9.61 Non-linear: 2 high-b SBCCs for FFQ correction, 2 low-b SBBCs not used for correction 10.13, -16.44 -145, -166 15, 29 7, 14 30.53, -7.25 -9, +9 Linear correction: -I pairs in arcs (schemes 3a, 3b) 29.71, -48.56 -5, +5 Best option Lowest 3 nm-rad emittance, but DA of 15s w/o errors may not be large enough ! Next  bullet # 3: study performance of ring design based on short FODO cells

Design Based on Short FODO Arc Cells Short FODO arc cells for low emittance, and new magnets Circumference: C = 2276.45 m = 2 x 926.27 m arcs + 2 x 211.95 m straights Natural chromaticity: [xH, xV] = [-116, -147] Two SBCCs near IP for non-linear chromaticity correction Emittance at 5 GeV (from Elegant): e = 5.5 nm-rad, ge = 54 mm-rad SBCCs 1x 3x 2y 4y IP

Arc Cell and SBCC – Short FODO Design FODO arc cell with new magnets Length 11.4 m (half of ion ring arc cell) Arc bending radius 155.45 m (as in the baseline) Phase advance 108o (x & y) 2 dipoles Length 3.6 m, bending angle 2.1 0.41 T @ 12 GeV Sagitta 1.65 cm 2 quadrupoles Length 0.56 m 21 T/m @ 12 GeV 2 sextupoles (2-family) New Arc IP Spin rotator SBCC FODO cells S1 S2 Low emittance SBCC Short dipoles with small bending angles  low H-function  low emittance contribution Two non-interleaved –I sextupole pairs per SBCC with sufficiently high beta functions Optimized phase advance from SBCC sextupoles to FFQs for best correction of non-linear chromaticity

Correction Performance – Short FODO Design 4 sextupole families in two SBCCs K2L = 2.2, -4.5, -2.6, 3.9 (1/m2) Optimized phase advance from sextupoles to IP 1x=3.7531, 2y=4.2535, 3x=5.2434, 4y=6.2413 Conventional 2-family arc sextupoles (opposite polarities in two arcs) 50 cells with x/y sextupoles per arc K2 = 14.7 and 6.0 (1/m3), L = 0.25 m Sufficiently large momentum range W functions IP  13σ Tune vs Dp/p b* vs Dp/p Qx = 57.22 Qy = 55.16

Dynamic Aperture – Short FODO Design Dynamic aperture at IP, no magnet errors, sx = 23.4 mm, sy = 4.7 mm @ 5 GeV 38σx 70σy So far, the best overall dynamic aperture (w/o errors)

Work Plan – Updated Optimize SBCC for low emittance in the optimized baseline design ‒ Done Can emittance be further reduced? Implement the SBCC in the low emittance design with TME-like arc cells and new magnets; match ring’s geometry; optimize chromaticity correction; check dynamic aperture ‒ Done If DA is good, continue with studies in bullet # 4 ‒ DA is “not good enough” Otherwise  study the low emittance design with short FODO-arc-cell and new magnets; optimize chromaticity correction; check dynamic aperture ‒ Done Further studies for the short FODO-arc-cell design Replace thin-lens trombones with quadrupole adjustment, verify performance Tune scan to find optimal tune for maximum DA Effects of misalignment and field errors on DA Implement orbit correction scheme (BPMs and correctors) Specify tolerances Effects of non-linear field errors on DA Regular magnets: start with the PEP-II field quality FF quads: specify tolerances

Conclusions and Outlook The study confirms that the SBCC scheme with sufficiently short dipoles provides an adequate non-linear chromaticity correction and yields a low emittance contribution in all the studied designs of the electron collider ring The optimized baseline design based on PEP-II magnets provides adequate chromaticity correction and DA, but a relatively high emittance of ~9 nm-rad @ 5 GeV The design based on TME-like arc cells with new magnets provides the lowest emittance of 3 nm-rad, but requires strong arc sextupoles leading to stronger non-linearities and smaller dynamic aperture The design based on short FODO arc cells with new magnets appears to be the best option so far. It provides a relatively low emittance of 5.5 nm-rad, adequate chromatic compensation and the best dynamic aperture (without errors). The plan for further studies is to focus on the short FODO ring design including: finalizing the optics; implementing orbit correction system; optimizing the tune for maximum DA; and investigating the impact of magnet errors and tolerance specification

Non-linear Beam Dynamics Studies for JLEIC Electron Collider Ring Thank You

Non-linear Beam Dynamics Studies for JLEIC Electron Collider Ring Back Up

PEP-II Measured Multipole Field Errors Systematic errors (DBN/Bref) Dipole at R = 30 mm N= 3 1.00E-5 Quadrupole at R = 44.9 mm N= 3 1.03E-3 4 5.60E-4 5 4.80E-4 6 2.37E-3 10 -3.10E-3 14 -2.63E-3 Sextupole at R = 56.52 mm N= 9 -1.45E-2 15 -1.30E-2 Random errors (DBN/Bref) Dipole at R = 30 mm N= 3 3.20E-5 4 3.20E-5 5 6.40E-5 6 8.20E-5 Quadrupole at R = 44.9 mm N= 3 5.60E-4 4 4.50E-4 5 1.90E-4 6 1.70E-4 10 1.80E-4 14 7.00E-5 Sextupole at R = 56.52 mm N= 5 2.20E-3 7 1.05E-3