(V)HE-LHC studies & long-term plan

Frank Zimmermann7th meeting of CERN Machine Advisory Committee

14 March 2013

work supported by the European Commission under the FP7 Research Infrastructures project EuCARD, grant agreement no. 227579

Recommendations from European Strategy Group, January 2013Recommendation #1:… Europe’s top priority should be the exploitation of the full potential of the LHC, including the high-luminosity upgrade of the machine and detectors with a view to collecting ten times more data than the initial design …

Recommendation #2:Europe needs to be in a position to propose an ambitious post-LHC accelerator project at CERN by the time of the next Strategy update [2017/18] when physics results from the LHC running at 14 TeV will be available [→ design studies & vigorous accelerator R&D programme]

Recommendation #3:There is a strong scientific case for an electron-positron collider, complementary to the LHC, that can study the properties of the Higgs boson and other particles with unprecedented precision and whose energy can be upgraded

projects beyond HL-LHC

• LHeC ep collider & Higgs factory• SAPPHiRE gg Higgs factory• HE-LHC/VHE-LHC pp/AA collider• TLEP/LEP3 e+e- Higgs factory ++• TLHeC/VHE-LHeC ep colliders…• ….• … others (ILC, CLIC, neutrino factory, …)

– not covered here

ERL LHeC:recirculatinglinac withenergy recovery

Large Hadron electron Collider (LHeC)baseline design

~600 pages

LHeC Conceptual Design ReportLHeC CDR published inJ. Phys. G: Nucl. Part. Phys. 39 075001 (2012)

LHeC ERL layouttwo 10-GeV SC linacs, 3-pass up, 3-pass down; 6.4 mA, 60 GeV e-’s collide w. LHC protons/ions

(C=1/3 LHC allows for ion clearing gaps)A. Bogacz, O. Brüning, M. Klein, D. Schulte, F. Zimmermann, et al

X(125) seems to strongly couple to gg

LHC CMS result (2012) LHC ATLAS result (2012) TeV Run-II result

a new type of collider?g

g

Ht, W, …

gg collider Higgs factory

another advantage:no beamstrahlung→ higher energy reachthan e+e- colliders

s-channel production;lower energy;no e+ source

“most” sensitive to new physics

combining photon science & particle physics!

K.-J. Kim, A. SesslerBeam LineSpring/Summer 1996

gg collider based on e-

few J pulseenergy with l~350 nm

LHeC-ERL SAPPHiRE* gg Higgs factory

*Small Accelerator for Photon-Photon Higgs production using Recirculating Electrons

Reconfiguring LHeC → SAPPHiRE

SAPPHiRE: a Small gg Higgs Factory

SAPPHiRE: Small Accelerator for Photon-Photon Higgs production using Recirculating Electrons

scale ~ European XFEL,about 10-20k Higgs per year

arXiv:1208.2827

LHeC R&D items

high-Q RF cavities & coupler dedicated ERL RF test facility IR layout Sapphire R&D items

gg IR, optical cavity, laser beam separation scheme, polarized e- gun

E. Todesco, L. Rossi, P.. McIntyre

HE-LHC: in LHC tunnel (2035-)ECoM=33 TeV,x1034cm-2s-1

VHE-LHC: new 80 km tunnel (2040?)ECoM=84-104 TeV,x1034cm-2s-1

J. Osborne, C. Waaijer, S. Myers

LHC→HE-LHC/VHE-LHCLHC is the 1st Higgs factory! ECoM=8-14 TeV,1034cm-2s-1

total cross section at 8 TeV: 22 pb1 M Higgs produced so far – more to come15 H bosons / min – and more to come

20-T dipole magnet

80 km tunnel

8 14 TeV: ggH x1.5

14 33 TeV: HH x6

HL-LHC (~2022-2030) will deliver ~9x more H bosons! ECoM=14 TeV,5x1034cm-2s-1

with luminosity levelingF. Cerutti, P. Janot

16-T or 20-T magnets

HH x42

- pushes magnet technology!

HE-LHC - studiesCERN working group in 2010

published report R. Assmann et al,“First Thoughts on a Higher-Energy LHC” CERN-ATS-2010-177

EuCARD-AccNet workshop HE-LHC’10 Proceedings (ed. E. Todesco, F. Zimmermann)“EuCARD-AccNet-EuroLumi Workshop: The High-Energy Large Hadron Collider”arXiv:1111.7188 ; CERN-2011-003

HiLumi LHC WP16 (coord. L. Rossi, dep. F. Zimmermann)

HE-LHC

2-GeV Booster

Linac4

SPS+

HE-LHC20-T dipole magnets

higher energytransfer lines

VHE-LHC - studies80-km tunnel study

John Osborne, C. Waaijer,“Pre-Feasability Assessment for an 80 km Tunnel

Project at CERN” Open Symposium - European StrategyPreparatory GroupContribution ID : 165

European Strategy briefing bookletsection in accelerator chapterR. Aleksan, C. Biscari, M. Lindroos, L. Rivkin, F. Zimmermann

VHE-LHC

VHE-LHC

VHE-LHC-LER =TLEP!

(Lucio Rossi)

a new 80-km tunnel for in the Geneva area?

«Pre-Feasibility Study for an 80-km tunnel at CERN»John Osborne and Caroline Waaijer, CERN, ARUP & GADZ, submitted to ESPG

80-km tunnel in Geneva area – “best” option

even better100 km?

80-km Tunnel Cost Estimate• Costs

– Only the minimum civil requirements (tunnel, shafts and caverns) are included

– 5.5% for external expert assistance (underground works only)

• Excluded from costing– Other services like cooling/ventilation/ electricity etc– service caverns– beam dumps– radiological protection– Surface structures– Access roads– In-house engineering etc etc

• Cost uncertainty = 50%• Next stage should include costing based on technical

drawings21 February 2013John Osborne & Caroline Waaijer

(CERN)

CE works Costs [kCHF]Underground

Main tunnel (5.6m)Bypass tunnel &

inclined tunnel access Dewatering tunnel

Small cavernsDetector caverns

Shafts (9m)Shafts (18m)

Consultancy (5.5%)TOTAL

(V)HE-LHC parameters – 1

O. Dominguez, L. Rossi, F.Z.

smaller?! (x1/4?)

(V)HE-LHC parameters – 2

O. Dominguez, L. Rossi, F.Z.

(s=100 mb)

numbers for lifetime and average integrated luminosity need to be updated for ~40% higher cross section at 100 TeV

emittances intensity

luminosityintegrated luminosity

time evolution for VHE-LHC (12 h) O. Dominguez

peak luminosity, pile up, radiation

are 5x1034 cm-2s-1 and pile up of 135 good targets for HE-LHC and VHE-LHC?

it would be easy to get more luminosity

radiation damping

use controlled blow up by noise injection:

• longitudinal plane (constant bunch length, Landau damping)

• transverse planes when needed(constant beam-beam tune shift)

choose round (ex=ey) or flat beams (ex>>ey)

shorter spacing (5 ns): better use of damping

SR heat load

HE-LHC: 3.7 W/mbeam screen at 40-60 K (instead of 4.6-20 K)+ warm photon absorbers for vacuum?+ HTS coating on 50-K beam screen??

VHE-LHC: 35.6 W/mdedicated photon stopsas developed by FNAL for VLHC by P. Bauer et al. (2001-2003)

collimation challenges

• higher energy density → need for more robust materials

• cross section for single diffractive scatteringincreases with energy → degraded

cleaning efficiency• smaller beam sizes & smaller gaps →

higher precision in collimator control• (warm? or shielded SC) magnets in the

collimator insertions

VHE-LHC: 99 W/mdedicated photon stops

R. Assmann, HE-LHC’10

quads in parameter plane

E. Todesco

Operational gradient as a function of coil aperture for LHC and US-LARP quadrupoles (markers), scaling laws for limits in Nb.Ti and Nb3Sn (solid curves) [7], and expected values for HE LHC arc and IR (stars).

HE-LHC

VHE-LHC arc

IR

?

?

HL-LHC prepares (V)HE-LHC!

injection scheme: SPS+ LHC VHE-LHC too expensive (50 MW power for cryo)

L. Rossi

possible arrangement in VHE-LHC tunnel

from H. Piekarz HE-LHC’10 Proc. p. 101

30 mm V gap50 mm H gap

L. Rossi

option 1: installation in the LHC tunnel “LEP3” + inexpensive (<0.1xLC)+ tunnel exists+ reusing ATLAS and CMS detectors+ reusing LHC cryoplants- interference with LHC and HL-LHC

option 2: in new 80-km tunnel “TLEP”+ higher energy reach, 5-10x higher luminosity+ decoupled from LHC/HL-LHC operation & construction+ tunnel can later serve for HE-LHC (factor 3 in energy from tunnel alone) with LHC remaining as injector- more expensive (?) but synergies w. VHE-LHC (& LHeC)

circular e+e- Higgs factories LEP3 & TLEP

key parameters

LEP3, TLEP(e+e- -> ZH, e+e- → W+W-, e+e- → Z,[e+e-→ t )

LEP3 TLEPcircumference 26.7 km 80 kmmax beam energy 120 GeV 175 GeVmax no. of IPs 4 4 luminosity at 350 GeV c.m. - 0.7x1034 cm-2s-1 luminosity at 240 GeV c.m. 1034 cm-2s-1 5x1034 cm-2s-1 luminosity at 160 GeV c.m. 5x1034 cm-2s-1 2.5x1035 cm-2s-1 luminosity at 90 GeV c.m. 2x1035 cm-2s-1 1036 cm-2s-1

at the Z pole repeating LEP physics programme in a few minutes…

beam lifetimeLEP2: • beam lifetime ~ 6 h • due to radiative Bhahba scattering (s~0.215 b)

TLEP:• with L~5x1034 cm−2s−1 at each of four IPs:

tbeam,TLEP~16 minutes from rad. Bhabha • additional lifetime limit due to beamstrahlung

(1) large momentum acceptance (dmax,RF≥3%), (2) flat(ter) beams, and/or

(3) fast replenishing(Valery Telnov, Kaoru Yokoya, Marco Zanetti)

SuperKEKB: t~6 minutes!

circular HFs – top-up injectiondouble ring with top-up injection

supports short lifetime & high luminosity

top-up experience: PEP-II, KEKB, light sources

A. Blondel

top-up injection: schematic cycle

10 s

energy of accelerator ring120 GeV

20 GeV

injection into collider

injection into accelerator

beam current in collider (15 min. beam lifetime)100%

99%

almost constant current

acceleration time = 1.6 s (assuming SPS ramp rate)

beamstrahlung lifetime• simulation w 360M macroparticles • t varies exponentially w energy acceptance h• post-collision E tail → lifetime t

beam lifetime versus acceptance dmax for 1 IP:

M. Zanetti

beamstrahlung lifetime

beam lifetime vs dmax for various ke=ex/ey

LEP3

M. Koratzinos

SuperKEKB willapproach ke~400-500

Circular & Linear HF:peak luminosity vs energy

K. Yokoya, KEK

LEP3/TLEP would be THE choice for e+e- collision energies up to ~370 GeV

LEP3 , TLEP

x 4 IPs

Report of the ICFA Beam Dynamics Workshop “Accelerators for a Higgs Factory: Linear vs. Circular” (HF2012) by Alain Blondel, Alex Chao, Weiren Chou, Jie Gao, Daniel Schulte and Kaoru Yokoya, FERMILAB-CONF-13-037-APC, IHEP-AC-2013-1, SLAC-PUB-15370, CERN-ATS-2013-032, arXiv:1302.3318 [physics.acc-ph]

comparing expected performance on Higgs coupling

TLEP has the best

capabilities

risk? - extrapolation from past experienceLEP2→TLEP-H SLC→ILC 250

peak luminosity x400 x2500

energy x1.15 x2.5

vertical geom. emittance x1/5 x1/400

vert. IP beam size x1/15 x1/150

e+ production rate x1/2 ! x65

commissioning time <1 year → ? >10 years →?

recent comment by eminent German particle physicist:“TLEP is much riskier and its performance highly uncertain;while the ILC performance numbers are very conservative” [?]

vertical rms IP spot sizes in nm LEP2 3500

KEKB 940SLC 500 LEP3 320 TLEP-H 220ATF2, FFTB 73 (35), 77SuperKEKB 50SAPPHiRE 18 ILC 5 – 8CLIC 1 – 2

in regularfont:achieved

in italics:designvalues

LEP3/TLEPwill learn from ATF2 &SuperKEKB

by*:

5 cm→1 mm

SAPPHiRE a step towardsILC/CLIC

proton injectorPROTONS

energy field[TeV] [T]0.026 0.117

SPS ↓ ↓ x 17.30.450 2.03

injector 0.450 0.16780 km tunnel ↓ ↓ x 9.0r = 9.0 km 4.1 1.5

I=75 kAwith I = 115-120 kA Bmax= 2 T

L. Rossi

ELECTRONS

energy field[GeV] [T]

3.5 0.016SPS ↓ ↓ x 5.7

20 0.090e+ / e- machine 20 0.0074

80 km tunnel ↓ ↓ x 8.8r = 9.0 km 175 0.0648

I =3 kA

electron injector

low injection field ~ 74 G;concern for field quality, but considered possîble ; already tested at 100 G; next magnet will be tested to 50 G

super-resistive cable

Cable: inner core of 40 mm Cu (700 mm2)+ outer core : 2 layers, 150 strands of MgB2, 1 kA each; Outer size 45 mm.120 kA =>120 k€/km !

For electrons: Cu water cooled, Jov 2.5 A/mm2

For protons: 800 A/strands120 kA (for >2.1 T); central copper acts as stabilizer

Cryostat : 60 mmHe envelope : 50 mmSC part: 2 layers MgB2 (Bi2212)150x1mmCu inner core 40 mmCooling hole: 10 mm

20 mm thick shield around cableGaps: 2 x V30xH60 mm

L. Rossi

VHE-LHC+TLEP tunnelLER for e+e- 350 GeV4 magnets, 8 channels4 channelP ~50 MW

LER p-p injector1 magnet, 2 channelsTop 10 K; Pcryostat < 10 MW

second magnet could be powered as return lineTBS: 100 K ?, photon stoppers

use of 1 or 2 channels for e ring for a 150 GeV e- vs. 7-50 TeV p

e- vs. ions also possible

L. Rossi

(V)HE-LHC R&D items

tunnel high-field magnets super-ferric/-resistive LER magnets SR handling

TLEP R&D items

high-power RF system by*=1 mm IR with large acceptance radiation shielding

PSB PS (0.6 km)SPS (6.9 km) LHC (26.7 km)

TLEP (80 km, e+e-, up to ~350 GeV c.m.)

VHE-LHC (pp, up to 100 TeV c.m.)same detectors!

also: e± (120 GeV) – p (7 & 50 TeV) collisions

possible long-term strategy

≥50 years of e+e-, pp, ep/A physics at highest energies

(E. Meschi)

HE-LHC (pp, 33 TeV c.m.)

LHeC & SAPPHiRE (9 km)

1980 1990 2000 2010 2020 2030

LHC Constr. PhysicsProto.Design, R&D

HL-LHC Constr. PhysicsDesign, R&D

LHeC& SAPPHiRE

Constr. PhysicsDesign, R&D

VHE-LHC Constr. PhysicsDesign, R&D

tentative time line

2040

TLEP Constr. PhysicsDesign, R&D

personal conclusions• need to pursue vigorous accelerator R&D to be

ready to propose new project by 2017/18 • TLEP, LEP3, SAPPHiRE & LHeC, HE-LHC and VHE-

LHC are exciting options with large synergies• TLEP superior in terms of energy & luminosity, and

extendable towards VHE-LHC, preparing ≥50 years of e+e-, pp, ep/A physics at highest energies

• TLEP comes for “free” (tunnel, magnets, & detectors “the same” as for VHE-LHC; RF system, cryogenics, & TLEP injector from LHeC)

• SuperKEKB will be important TLEP demonstrator!

“A circle is a round straight line with a hole in the middle.”

Mark Twain, in "English as She Is Taught", Century Magazine, May 1887

Appendix

• example parameters for HL-LHC, LHeC, LEP3, TLEP, HE-LHC, VHE-LHC, TLHeC, VHE-TLHeC

• references & events

HL-LHC parametersparameter symbol nominal HL-LHC 25 ns HL-LHC 50 ns

beam energy Eb [TeV] 7 7 7protons per bunch Nb [1011] 1.15 2.0 3.3#bunches per beam nb 2808 1404 2808beam current I [A] 0.58 1.01 0.83rms bunch length sz [cm] 7.55 7.55 7.55beta* at IP1&5 b* [m] 0.55 0.15 0.15full crossing angle qc [mrad] 285 (9.5s) 590 (12.5s) 590 (11.4s)normalized emittance ge [mm] 3.75 2.5 3.0IBS e rise time (z, x) tIBS,z/x [h] 57, 103 24, 17 (ATS) 17, 15 (ATS)max. total b-b tune shift DQtot 0.011 0.013 0.017potential pk luminosity L [1034 cm-2s-1] 1 24 25actual leveled pk luminosity Llev [1034 cm-2s-1] 1 5 2.5max. #events / #ing (pile up) 19 140 140effective beam lifetime teff [h] 44.9 15.6 25.7level time, run time tlevel [h], trun [h] 0, 15.2 7.8, 11.5 17.2, 20.1 needed availability A [%] (50) 59 78needed efficiency E [%] (38) 41 63annual integrated luminosity Lint[fb-1] (37) 250 200

parameter [unit] LHeC

species e± p, 208Pb82+

beam energy (/nucleon) [GeV] 60 7000, 2760

bunch spacing [ns] 25, 100 25, 100

bunch intensity (nucleon) [1010] 0.1 (0.2), 0.4 17 (22), 2.5

beam current [mA] 6.4 (12.8) 860 (1110), 6

rms bunch length [mm] 0.6 75.5

polarization [%] 90 (e+ none) none, none

normalized rms emittance [mm] 50 3.75 (2.0), 1.5

geometric rms emittance [nm] 0.43 0.50 (0.31)

IP beta function b*x,y [m] 0.12 (0.032) 0.1 (0.05)

IP rms spot size [mm] 7.2 (3.7) 7.2 (3.7)

synchrotron tune - 0.0019

hadron beam-beam parameter 0.0001 (0.0002)

lepton disruption parameter D 6 (30)

hourglass reduction factor Hhg 0.91 (0.67)

pinch enhancement factor HD 1.35 (0.3 for e+ )

luminosity/ nucleon [1033 cm-2s-1] 1 (10), 0.2

LHeC baseline (& pushed) parameters

LEP2 LHeC LEP3 TLEP-Z TLEP-H TLEP-tbeam energy Eb [GeV] circumference [km] beam current [mA] #bunches/beam #e−/beam [1012] horizontal emittance [nm] vertical emittance [nm] bending radius [km] partition number Jε momentum comp. αc [10−5] SR power/beam [MW] β∗

x [m] β∗

y [cm] σ∗

x [μm] σ∗

y [μm] hourglass Fhg ΔESR

loss/turn [GeV]

104.526.7442.3480.253.11.118.5111.552703.50.983.41

6026.710028085652.52.61.58.1440.181030160.990.44

12026.77.244.0250.102.61.58.1500.20.1710.320.596.99

45.58011802625200030.80.159.01.09.0500.20.1780.390.710.04

1208024.38040.59.40.059.01.01.0500.20.1430.220.752.1

175805.4129.020 0.19.01.01.0500.20.1630.320.659.3

LEP3/TLEP parameters -1 soon at SuperKEKB:bx*=0.03 m, bY*=0.03 cm

SuperKEKB:ey/ex=0.25%

LEP2 LHeC LEP3 TLEP-Z TLEP-H TLEP-tVRF,tot [GV] dmax,RF [%]ξx/IP ξy/IPfs [kHz] Eacc [MV/m] eff. RF length [m] fRF [MHz] δSR

rms [%] σSR

z,rms [cm] L/IP[1032cm−2s−1] number of IPs Rad.Bhabha b.lifetime [min] ϒBS [10−4] nγ/collision DdBS/collision [MeV] DdBS

rms/collision [MeV]

3.640.770.0250.065 1.67.54853520.221.611.2543600.20.080.10.3

0.50.66N/AN/A0.6511.9427210.120.69N/A1N/A0.050.160.020.07

12.05.70.090.082.19206007000.230.319421890.603144

2.04.00.120.121.29201007000.060.19103352 7440.413.66.2

6.09.40.100.100.44203007000.150.174902 32150.504265

12.04.90.050.050.43206007000.220.25652 54150.516195

LEP3/TLEP parameters -2 LEP2 was not beam-beam limited

LEP data for 94.5 - 101 GeV consistently suggest a beam-beam limit of ~0.115 (R.Assmann, K. C.)

collider parameters TLHeC VHE-TLHeCspecies e± p e± pbeam energy [GeV] 120 7000 120 50000bunch spacing [ms] 3 3 3 3bunch intensity [1011] 5 3.5 5 3.5beam current [mA] 24.3 51.0 24.3 51.0rms bunch length [cm] 0.17 4 0.17 2rms emittance [nm] 10,2 0.40 10,2 0.06bx,y*[cm] 2,1 60,5 0.5,0.25 60,5sx,y* [mm] 15, 4 6, 2beam-beam parameter x 0.05, 0.09 0.03,0.01 0.07,0.10 0.03,0.007hourglass reduction 0.63 0.42CM energy [TeV] 1.8 4.9luminosity [1034cm-2s-1] 0.5 1.6

parameters for TLHeC & VHE-TLHeC (e- at 120 GeV)

TLEP/LEP3 events & referencesA. Blondel, F. Zimmermann, “A High Luminosity e+e- Collider in the LHC Tunnel to

study the Higgs Boson,” arXiv:1112.2518v1, 24.12.’11K. Oide, “SuperTRISTAN - A possibility of ring collider for Higgs factory,”

KEK Seminar, 13 February 20121st EuCARD LEP3 workshop, CERN, 18 June 2012A. Blondel et al, “LEP3: A High Luminosity e+e- Collider to study the Higgs Boson,”

arXiv:1208.0504, submitted to ESPG KrakowP. Azzi et al, “Prospective Studies for LEP3 with the CMS Detector,”

arXiv:1208.1662 (2012), submitted to ESPG Krakow2nd EuCARD LEP3 workshop, CERN, 23 October 2012P. Janot, “A circular e+e- collider to study H(125),” PH Seminar, CERN, 30 October 2012ICFA Higgs Factory Workshop: Linear vs Circular, FNAL, 14-16 Nov. ’12A. Blondel, F. Zimmermann, “Future possibilities for precise studies of the X(125)

Higgs candidate,” CERN Colloquium, 22 Nov. 20123rd TLEP3 Day, CERN, 10 January 20134th TLEP mini-workshop, CERN, 4-5 April 2013

https://espace.cern.ch/LEP3 https://cern.ch/accnet

SAPPHiRE/LHeC events & referencesS. A. Bogacz, J. Ellis, L. Lusito, D. Schulte, T. Takahashi, M. Velasco, M. Zanetti,

F. Zimmermann, “SAPPHiRE: a Small Gamma-Gamma Higgs Factory,”arXiv:1208.2827

D. Asner et al., “Higgs physics with a gamma gamma collider based on CLIC I,” Eur. Phys. J. C 28 (2003) 27 [hep-ex/0111056].

J. Abelleira Fernandez et al, “Large Hadron Electron Collider at CERN - Report on the Physics and Design Concepts for Machine and Detector,” Journal of Physics G: Nuclear and Particle Physics 39 Number 7 (2012) arXiv:1206.2913

Yuhong Zhang, “Design Concept of a g-g Collider-Based Higgs Factory Driven by Energy Recovery Linacs,” arXiv:1211.3756

E. Nissen, “Optimization of Recirculating Linacs for a Higgs Factory,” prepared for HF2012

ICFA Higgs Factory Workshop: Linear vs Circular, FNAL, 14-16 Nov. ’12J. Limpert, T. Schreiber, A. Tünnermann, “Fiber lasers and amplifiers: an ultrafast

performance evolution,” Applied Optics, Vol. 49, No. 25 (2010)1st EuCARD SAPPHiRE Day, CERN, 19 February 2013

https://cern.ch/accnet

HE-LHC &VHE-LHC events & references

R. Assmann, R. Bailey, O. Brüning, O. Dominguez, G. de Rijk, J.M. Jimenez, S. Myers, L. Rossi, L. Tavian, E. Todesco, F. Zimmermann, “First Thoughts on a Higher-Energy LHC,” CERN-ATS-2010-177

E. Todesco, F. Zimmermann (eds), “EuCARD-AccNet-EuroLumi Workshop: The High-Energy Large Hadron Collider,” Proc. EuCARD-AccNet workshop HE-LHC’10 , Malta, 14-16 October 2010, arXiv:1111.7188 ; CERN Yellow Report CERN-2011-003HiLumi LHC WP6 HE-LHCJoint Snowmass-EuCARD/AccNet-HiLumi meeting `Frontier Capabilities for Hadron

Colliders 2013,‘ CERN, 21-11 February 2013

https://cern.ch/accnet

http://hilumilhc.web.cern.ch/HiLumiLHC/activities/HE-LHC/WP16/