TLEP: a first step on a long vision for HEP. M. Koratzinos Univ. of Geneva On behalf of the TLEP study group Athens, 6 December 2013. C ontents. The physics case Circular collider challenges TLEP implementation TLEP physics reach TLEP design study.
TLEP: a first step on a long vision for HEP
Univ. of Geneva
On behalf of the TLEP study group
Athens, 6 December 2013
Acknowledgements: I am indebted to the whole TLEP community and especially R. Aleksan, A. Blondel, P. Janot, F. Zimmermann for liberal use of material
This talk would not have been complete without the comparison data with the ILC. I hope I have represented them accurately
Where is the energy scale for new physics (exact value of d depends on coupling and model)
Assumptions: 20mV/m, 90% dipole fill factor.
What is plotted is the ratio of RF length to total arc length
TLEP175 sits comfortably below the 1% line
LEP2 had a ratio of RF to total arc length of 2.2%
Luminosity of a circular collider is given by
Which can be transformed in terms of
The maximum luminosity is bound by the total power dissipated, the maximum achievable beam-beam parameter (the beam-beam limit), the bending radius, the beam energy, , and the hourglass effect (which is a function of σzand )
The maximum beam-beam parameter is a function of the damping decrement:
Or, more conveniently:
The damping decrement is the fractional energy loss from one IP to the next.
Therefore, for a specific machine, for 1IP is generally higher than for 2IPs
We are opting for a realistic β*y value of 1mm. σz beam sizes vary from 1mm to 3mm. In this range the hourglass effect is between 0.9 to 0.6
Self-consistentσz at different energies for TLEP
Plot on left is if we run with a value of the beam-beam parameter of 0.1
Above ~180 GeV is difficult to run without opting for a more modest beam-beam parameter value (which would reduce the luminosity)
TLEP Latest parameter set, mom. acceptance 2.2%
Can even run at 250GeV with a beam-beam parameter of 0.05
Possible TLEP location
BNL 5-cell 700 MHz cavity
As a self-standing project :
Same order of magnitude as LHC
As an add-on to the VHE-LHC project :
Very cost-effective : about 2-3 billion CHF
Cost per Higgs boson : 1 - 3 kCHF / Higgs
(ILC cost : 150 k$ / Higgs) [ NB : 1CHF ~ 1$ ]
Cost for the 80 km version : the 100 km version might be cheaper.
Not endorsed by anybody
Note: detector costs not included – count 0.5 per detector (LHC)
(1): J. Osborne, Amrupstudy, June 2012
(2): Extrapolation from LEP
(3): O. Brunner, detailed estimate, 7 May 2013
80-100 km tunnel
(4): F. Haug, 4th TLEP Days, 5 April 2013
(5): K. Oide : factor 2.5 higher than KEK,
estimated for 80 km ring
(6): 24,000 magnets for collider & injector;
cost per magnet 30 kCHF (LHeC);
Highest consumer is RF:
Limited by Klystron CW efficiency of 65%. This is NOT aggressive and we hope to be able to do better after dedicated R&D
Total power consumption for 350GeV running:
IPAC13 TUPME040, arXiv:1305.6498 [physics.acc-ph]
Too pessimistic! 2nm @120GeV or lower should he easy
By definition, in a project like TLEP, from the moment a set of parameters is published it becomes obsolete and we now already have an improved set of parameters.
The new parameter set contains improvements to our understanding, but does not change the big picture.
Revised (taking into account BS) but similar
IPAC13 TUPME040, arXiv:1305.6498 [physics.acc-ph]
TLEP : Instantaneous lumi at each IP (for 4 IP’s)
Instantaneous lumi summed over 4 IP’s
tt , 5.1034
Our first paper treating exclusively the physics case
will be published in JHEP shortly (submitted 23/9/2013): M.Bicer et el., “First Look at the Physics Case of TLEP” http://arxiv.org/abs/1308.6176(130 authors)
Author(s): M. Bicer, H. Duran Yildiz, I. Yildiz, G. Coignet, M. Delmastro, T. Alexopoulos, C. Grojean, S. Antusch, T. Sen, H.-J. He, K. Potamianos, S. Haug, A. Moreno, A. Heister, V. Sanz, G. Gomez-Ceballos, M. Klute, M. Zanetti, L.-T. Wang, M. Dam, C. Boehm, N. Glover, F. Krauss, A. Lenz, M. Syphers, C. Leonidopoulos, V. Ciulli, P. Lenzi, G. Sguazzoni, M. Antonelli, M. Boscolo, O. Frasciello, C. Milardi, G. Venanzoni, M. Zobov, J. van der Bij, M. de Gruttola, D.-W. Kim, M. Bachtis, A. Butterworth, C.Bernet, C. Botta, F. Carminati, A. David, D. d’Enterria, G. Ganis, B. Goddard, G. Giudice, P. Janot, J. M. Jowett, C. Lourenco, L. Malgeri, E. Meschi, F. Moortgat, P. Musella, J. A. Osborne, L. Perrozzi, M. Pierini, L. Rinolfi, A. de Roeck, J. Rojo, G. Roy, A. Sciaba, A. Valassi, C. S. Waaijer, J. Wenninger, H. Woehri, F. Zimmermann, A. Blondel, M. Koratzinos, P. Mermod, Y. Onel, R. Talman, E. CastanedaMiranda, E. Bulyak, D. Porsuk, D. Kovalskyi, S. Padhi, P. Faccioli, J. R. Ellis, M. Campanelli, Y. Bai, M. Chamizo, R. B. Appleby, H. Owen, H. Maury Cuna, C. Gracios, G. A. Munoz-Hernandez, L. Trentadue, E. Torrente-Lujan, S. Wang, D. Bertsche, A. Gramolin, V. Telnov, P. Petrov, P. Azzi, O. Nicrosini, F. Piccinini, G. Montagna, F. Kapusta, S. Laplace, W. da Silva, N. Gizani, N. Craig, T. Han, C. Luci, B. Mele, L. Silvestrini, M. Ciuchini, R. Cakir, R. Aleksan, F. Couderc, S. Ganjour, E. Lancon, E. Locci, P. Schwemling, M. Spiro, C. Tanguy, J. Zinn-Justin, S. Moretti, M. Kikuchi, H. Koiso, K. Ohmi, K. Oide, G. Pauletta, R. Ruiz de Austri, M. Gouzevitch, S. Chattopadhyay
The mass dependence of the couplings of the Higgs boson to fermions and gauge bosons, from a two-parameter fit (dashed line) to a combination of the CMS and ATLAS data. The dotted lines bound the 68% C.L. interval. The value of the coupling of the Higgs boson to the c quark shown in the figure is a prediction of the fit. The solid line corresponds to the Standard Model prediction
Unpolarized cross sections
PJ and G. Ganis
Z → All
Z → nn
(TLEP : CMS Full Simulation + some extrapolations for cc, gg)
From P. Azzi et al.
Luminosity E Spectrum Effect on top threshold
Z lineshape, asymetries WW threshold scan New Physics in loops ?
is a clear advantage
TLEP as a Tera-Z and Oku-W Factory (2)
NB: ILC limited to a factor > 30 larger errors
Warning : indicative only.
Complete study being done
Very stringent SM closure test.
Sensitivity to weakly-interacting
BSM Physics at a scale > 10 TeV
26 Working Groups: Accelerator / Experiment / Phenomenology
Soon to be replaced by an official structure in the framework of FCC
The twopillars: pp and e+e-
mandate is to deliver full CDR for both machines
with an extendedcostreview
The combination of TLEP and the VHE-LHC offers, for a great cost effectiveness, the best precision and the best search reach of all options presentlyon the market.
First look at The Physics Case of TLEP
arXiv:1308.6176v2 [hep-ex] 22 Sep 2013
FCC front-page news in the CERN bulletin:
…meanwhile in the same issue:
for the maximum field (it would be smaller for a smaller field)
d) To stay at the forefront of particle physics, 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, when physics results from the LHC running at 14 TeV will be available.
CERN should undertake design studies for accelerator projects in a global context, with emphasis on proton-proton and electron-positron high-energy frontier machines.These design studies should be coupled to a vigorous accelerator R&D programme, including high-field magnets and high-gradient accelerating structures, in collaboration with national institutes, laboratories and universities worldwide.
The two most promising lines of development towards the new high energyfrontier after the LHC are proton-proton and electron-positron colliders. Focused design studies are required in both fields, together with vigorous accelerator R&D supported by adequate resources and driven by collaborations involving CERN and national institutes, universities and laboratories worldwide. The Compact Linear Collider (CLIC) is an electron-positron
machine based on a novel two-beam acceleration technique, which could, in stages, reach a centre-of-mass energy up to 3 TeV. A Conceptual Design Report for CLIC has already been prepared. Possible proton-proton machines of higher energy than the LHC include HE-LHC, roughly doubling the centre-of-mass energy in the present tunnel, and VHE-LHC, aimed at reaching up to 100 TeV in a new circular 80km tunnel. A large tunnel such as this could also host a circular e+e-machine (TLEP) reaching energies up to 350 GeV with high luminosity.
HL-LHC : One experiment only
… CMS Scenario 1
CMS Scenario 2
CMS, July 13
In bold, theory uncertainty are assumed to be divided by a factor 2,
experimental uncertainties are assumed to scale with 1/√L,
and analysis performance are assumed to be identical as today
(HL-LHC : One experiment only)
Note : mm collider
DGH/GH ~ 5%
Particularly difficult for √s < 2-3 TeV
Few per-cent precision will need VHE-LHC
J. Wells et al.
Snowmass, Aug 13