Slide 1

TLEP ... Lattice Design & Beam Optics

B. Holzer / B. Haerer

latest (good) newsParameter-List on TLEP-WEB Page is hopelessly out of dateand out of reality

Quo usque tandem abutere, Catilina, patientia nostra?Present study case:

E=175 GeV, = 2nm / 0.002nm

Lcell=50m

Dipole: Ndipole = 2932 Ldipole = 21.3 mdue to techn. reasons: 2 * 11 m bending angle = 2.14 mrad B0 = 580 Quadrupole (arc):Lquadrupole = 1.5 mk=3.55*10-2 m-2 g=20.7 T/maperture: r0=30 =11mmBtip= 0.23 T 100m, Dx= 15.3 cm

FoDo CellAt present the dipole length is symbolic. Due to technical reasons we think of putting 2 dipoles of 11m length each between the quadsTLEP ... Lattice Design (175 GeV) V9e -> V10

TLEP ... Lattice Design24 Arcs : built out of 56 standard FoDo cells & 2 half bend cells at beginning and endlength of arc: 3.0kmeach arc is embedded in dispersion free regions ...

arcs are connected by straight. sections ... 12 long (mini and RF) ... 12 ultra shorties tbcto be optimised TLEP OctantStraight Arc Arc Straightarcs are connected in pairs via a disp-free-empty cell-> only reason: in case of additional insertions we get the boundary conditions for free.

TLEP Arc-Straights8 Straights : 9 empty (i.e. dispersion free) FoDo cells including matching sections arc-straight, l = 450m

arc cellsempty cellsarc cellsempty cellsto be optimised: y at matching section, needs an additional quadrupole lens already built in but not used yet. and / or optimisation of the lens positionsTLEP The Ringrf-sectionsLring = 79.9km4 min- betas, 24 disp free straights, 12 long straights 8 for rf equipment, 4 for mini-betas & rf

************TLEP Lattice ... converging to a realistic approachQuestions to answer:

* hardware of the latticee.g. LHeC type dipoles* feasibility of the cell designflanges / pumps / BPMs etc* what about synchrotron radiation ... do we need absorbers and where ?Fluka / Helmut / Manuela* vacuum designMark, Roberto, Cedric * tolerance considerationsdo we get the hor & vert. emittance ????BH & BH* what kind of correctors & BPMs do we need and where to install themAlexander (Petra 3), Francis, Montse (ALBA)* do we need a weak bend at the end of the arc (YES) and how weak should it be ?Helmut & family* how does the lattice scale with cell length / phase advance BH &BHTLEP V9e ... first FLUKA resultsFLUKA status and plan

Sixth TLEP workshopCERN, 16 -18 October 2013F. Cerutti#, A. Ferrari#, L. Lari*, A. Mereghetti#

power density in the dipole chambers has to be reduced by installation of lead shield

power density along the dipoles -> shorter dipole design

Peak Dose on the coilsTLEP V9e ... first FLUKA results

the ideal FLUKA world ;-))TLEP V9e ... first Vacuum Considerations (court. C. Garion, R. Kersevan)schematic cell layout:assuming reasonable driftsrealistic BB interconnects

Sy-Li Absorber

realistic BQ interconnectsTLEP V10 ..Lattice Modifications: court. B. Haerer

V9e cellV10 cellold Cell Layout? ... do we keep the cell length ?? ... do we cut the dipole length ? ? ... do we enlarge the FoDO length ?Next steps:

1) Optics fine tuning: including vacuum design & Fluka

2) Tolerances & Emittances for a realistic machinecan we keep the small vertical

3) Include orbit corrections & BPMs (cell length ??)PETRA3, ALBA ... nested correctors ?

4) Include a weak bend at the end of the arc... how weak -> sy-li fan geometry, Ecrit

5) Lattice for lower energiesscaling of -> re-shuffle FoDo structure

6) goto 1), goto 2)

TLEP V.xxx ...Lattice Modifications for smaller energies

equilibrium emittancescaling of dispersion in a FoDo

scaling of D with phase advance90oLcell = 50m

Lcell = 100m

Lcell = 150mcoarse tuning via cell length, fine tuning via phase advance & wigglers

TLEP Z TLEP W TLEP H TLEP t TLEP ttH & ZHH

Ebeam [GeV] 45 80 120 175 250 circumf. [km] 100 100 100 100 100 beam current [mA] 1440 154 29.8 6.7 1.6 #bunches/beam 7500 3200 167 160 20 10 #e!/bunch [1011] 4.0 1.0 3.7 0.88 7.0 3.3 # arc cells in units of base cell

6 2 2 1 2 1

horiz. emit. [nm] 29.2 3.3 7.5 2.0 16.0 4.0 vert. emit. [nm] 0.06 0.017 0.015 0.002 0.016 0.004 bending rad. [km] 11.0 11.0 11.0 11.0 11.0 !" 500 200 500 1000 1000 mom. c. "c [10!5] 3.6 0.4 0.4 0.1 0.4 0.1 Ploss,SR/beam [MW] 50 50 50 50 50 #!x [m] 0.5 0.2 0.5 1.0 1.0 #!y [mm] 1.0 1.0 1.0 1.0 1.0 $!x [%m] 121 26 61 45 126 63 $!y [%m] 0.25 0.13 0.12 0.045 0.126 0.063 &SRrms [%] 0.05 0.09 0.14 0.20 0.29 !SRz,rms [mm] 1.16 0.91 0.98 0.68 1.35 1.56 !totrms [%] 0.13 0.20 0.30 0.23 0.29 0.34 #totz,rms [mm] 2.93 1.98 2.11 0.77 1.95 1.81 hourglass Fhg 0.61 0.71 0.69 0.90 0.71 0.73 ESRloss/turn [GeV] 0.03 0.3 1.7 7.5 31.4 VRF,tot [GV] 2 2 6 12 35 !|| (turns) 1319 242 72 23 8 "max,RF [%] 5.3 10.6 13.4 19.0 9.5 5.9 "x/IP 0.068 0.086 0.094 0.057 0.075 "y/IP 0.068 0.086 0.094 0.057 0.075 fs [kHz] 0.77 0.19 0.27 0.14 0.29 0.266 Eacc [MV/m] 3 3 10 20 20 eff. RF length [m] 600 600 600 600 1750 fRF [MHz] 800 800 800 800 800 " /IP[1032cm#2s#1] 5860 1640 508 132 104 48 number of IPs 4 4 4 4 4 beam lifetime [min] (rad. Bhabha)

99 38 24 21 26 13

beam lifetime [min] (beamstrahlung Telnov with#$=2%)

>1025 >106 38 14 2.1 [11.6 with $=2.5%]

0.3 [2.8 with $=3%]