D. Trbojevic, N. Tsoupas, S. Tepikian, B. Parker, E. Pozdeyev, Y. Hao, D. Kayran, J. Beebe-Wang, C. Montag, V. Ptitsyn, and V. Litvinenko eRHIC and MeRHIC Lattices and Interaction Regions

eRHIC and MeRHIC Lattice and Interaction Regions New  *=5 cm IR design of the eRHIC: - Arcs and linacs in the RHIC existing tunnel. - Interaction regions: Wide angle acceptance and the high luminosity IR with  * =5 cm. Lattice design of the MeRHIC: - RHIC modification – Steven Tepikian - Lattice of the Energy recovery linac– Eduard Pozdeyev - Asynchronous arcs – Dmitri Kayran, Dejan Trbojevic - Vertical splitters – Nicholaus Tsoupas - IP and detector protection J. Beebe-Wang Summary and plan. Dejan Trbojevic EIC-Stony Brook, January 10-12, 20102

Recirculation passes in eRHIC design At present design of eRHIC the beam passes the main linac five times during acceleration. Four of the beam recirculation passes will be placed in the tunnel. Lower energy pass can be put locally. Possible location of the recirculation passes in the tunnel Four recirculation passes PHENIX STAR e-ion detector eRHIC Main ERL (1.9 GeV) Low energy recirculation pass Beam dump Electron source Possible locations for additional e-ion detectors Dejan Trbojevic EIC-Stony Brook, January 10-12, 20103

Previous work on asynchronous lattice (1997) 1997 Particle Accelerator Conference, Vancouver, B.C., Canada, 5/12-16/97, “A Proton Driver for the Muon Collider Source with a Tunable Momentum Compaction Lattice”, D. Trbojevic et. all. Dejan Trbojevic EIC-Stony Brook, January 10-12, 20104

FMC cell (D. Trbojevic) Dipole filling factor: 54% Reduced length Tuned to ~0 momentum compaction For 10GeV: Largest gradient: 7.7 T/m Dipole field: 0.16 T Dipole length: 5.5 m Quad length: 0.6 m 81 m Basic cell for the arcs Dejan Trbojevic EIC-Stony Brook, January 10-12, 20105

Separated functions: R 56 tuning: arcs Phase trombone: straights Path length tuned: in area of IR insertion (IR12) One sextant with asynchronous cells Arc and straights with no IR Dejan Trbojevic EIC-Stony Brook, January 10-12, 20106

Interaction Straight Layout H-planeV-plane Presently considered geometry of the interaction region straight. Ongoing work on the optics to minimize (or eliminate) dispersion at the IP. Dejan Trbojevic EIC-Stony Brook, January 10-12, 20107

Second high-Luminosity IR in eRHIC for Q 2 detector using just built magnets from US LARP Magnet Program Dejan Trbojevic EIC-Stony Brook, January 10-12, New eRHIC IR designs with  * =5 cm with the triplet magnets 4.5 m away from the IP. This is for different Q 2 physics. Examining two ways for the chromaticity corrections: 1.With zero dispersion at the IP but non-zero slope of dispersion 2.With zero dispersion and zero slope at the IP. Quadrupole magnets have gradients of 200 T/m and are 1.6 m, 1 m and 0.85 long.

Second high-Luminosity IR in eRHIC for Q 2 detector using just built magnets from US LARP Magnet Program Large aperture, Nb 3 Sn Quadrupoles for LHC Upgrade 90 mm G > 250 T/m High Performance Conductor Development Length Scale-up Steve Gourlay Dejan Trbojevic EIC-Stony Brook, January 10-12, 20109

Assembled LHC triplet Dejan Trbojevic EIC-Stony Brook, January 10-12,

Dejan Trbojevic EIC-Stony Brook, January 10-12, RHIC lattice for the present Au-Au run 2010 Dispersion at the IP is zero with non-zero slope. The D x ~1.5m at the triplets.

Chromaticity correction in RHIC with the IR sextupoles sextupoles in triplets ON Chromatic correction in the arc sextupoles strength is reduced improved lifetime Dejan Trbojevic EIC-Stony Brook, January 10-12,

Present RHIC lattice with  * =0.6 m Chromaticities:  x  x  x  p/p   y  requires correction with 32 A of 100 A maximum for ‘defocusing’ sextupoles, and half for the ‘focusing’ sextupoles Dejan Trbojevic EIC-Stony Brook, January 10-12,

Methods of correcting the IP chromaticities Dejan Trbojevic EIC-Stony Brook, January 10-12,

4.5 m Dejan Trbojevic EIC-Stony Brook, January 10-12,

Dejan Trbojevic EIC-Stony Brook, January 10-12,

Dejan Trbojevic EIC-Stony Brook, January 10-12,

Dejan Trbojevic EIC-Stony Brook, January 10-12,

RHIC lattice with  * =0.05 m Chromaticities:  x  x  x  p/p   y  requires correction with 32 A of 100 A maximum for ‘defocusing’ sextupoles, and half for the ‘focusing’ sextupoles Dejan Trbojevic EIC-Stony Brook, January 10-12, CIRCUMFERENCE = M  X = RAD x =  x = RADIUS = M  y = RAD y =  y =  =(DS/S)/(DP/P)= TGAM=( , ) MAXIMA ---  X ( 1261) =  y ( 1230) = D x = MINIMA ---  X ( 1247) =  y ( 1247) = D x = CHROMATICITY AFTER SEXTUPOLE CORRECTIONS  x =  y = AMPLITUDE DEPENDENCE OF TUNES DUE TO SEXTUPOLES x = *  x *  y  x ~  x = 0.2 mm mrad  x= y = – 6570 *  x *  y

MeRHIC - Lattice and IR Dejan Trbojevic EIC-Stony Brook, January 10-12, Lattice design of the MeRHIC: - RHIC modification – Steven Tepikian - Lattice of the Energy recovery linac– Eduard Pozdeyev - Asynchronous arcs and IP – Dmitri Kayran, Dejan Trbojevic - Vertical splitters – Nicholaus Tsoupas - IP and detector protection: J. Beebe-Wang

© J.C.Brutus, J. Tuozzolo, D. Trbojevic, G. Mahler, B. Parker, W. Meng 21 Dejan Trbojevic EIC-Stony Brook, January 10-12,

22 Linacs, spreaders, and an arc Dejan Trbojevic EIC-Stony Brook, January 10-12,

Magnets: Preliminary Design Dejan Trbojevic EIC-Stony Brook, January 10-12,

Switchyard at the linac 4GeV 0.1GeV 1.4GeV 2.7GeV m m 1.25 m 0.55 m 0.16 m m m m Q4g3 D4g3 Dejan Trbojevic EIC-Stony Brook, January 10-12,

Switchyard at the linac 4GeV 0.1GeV 1.4GeV 2.7GeV m Q4g 3 hb2 u hb3 u qu4 f qu5 d D4g4u qu3d qu2f qu1d hb4u hbdu hb1u Dejan Trbojevic EIC-Stony Brook, January 10-12,

Vertical splitters – Nicholaus Tsoupas Dejan Trbojevic EIC-Stony Brook, January 10-12,

RHIC lattice modification – Joanne-Beebe Wang Dejan Trbojevic EIC-Stony Brook, January 10-12,

RHIC lattice modification – Steven Tepikian   ~0.4 m Dejan Trbojevic EIC-Stony Brook, January 10-12,

Requirements for the Energy Recovery Linac: Geometrical constraints: If it is possible use the existing interaction region at RHIC 2 o’clock and wider tunnel to place the superconducting linac inside it. Minimize civil construction cost: Dejan Trbojevic EIC-Stony Brook, January 10-12,

Zero dispersion IP and detector Dejan Trbojevic EIC-Stony Brook, January 10-12,

Dejan Trbojevic EIC-Stony Brook, January 10-12,

One Flexible Momentum Compaction Cell: QF/2 QF3 QD QF/2 QD3 QD QF3 Dejan Trbojevic EIC-Stony Brook, January 10-12,

Asynchronous arcs: 3.35 GeV Betatron Functions Dmitri Kayran, Dejan Trbojevic Dejan Trbojevic EIC-Stony Brook, January 10-12,

Asynchronous arcs: 4.00 GeV Dmitri Kayran, Dejan Trbojevic R=8.88 m R=12.3 m L BL = 1.55 m B y = T  = rad m Dejan Trbojevic EIC-Stony Brook, January 10-12,

Summary: Lattice design of the eRHIC and MeRHIC is complete. eRHIC: High Luminosity RHIC lattice – The dynamical aperture – many turn tracking studies of the RHIC lattice with  *=5 cm are in progress. Arc asynchronous lattice with splitters is completed. IR designs for large angle IP and high luminosity are in progress. Arc magnets samples are already built. MeRHIC: Complete design and layout of the multi-pass electron and accommodations of the RHIC lattices are completed. Preliminary magnet design is completed. Detail cost estimate of the 4 GeV Medium electron – ion collider is completed Dejan Trbojevic EIC-Stony Brook, January 10-12,