Overview of Future Colliders

Transcription

1 Overview of Future Colliders Hongbo Zhu, Beijing IX International Conference on Interconnections between Particle Physics and Cosmology (PPC2015), June 29 th - July 3 rd 2015, Deadwood, South Dakota

2 Colliders over the Decays V D Shiltsev, High energy particle colliders: past 20 years, next 20 years and beyond, Physics-Uspekhi 55 (10) (2012) 2

3 Outline Future colliders ILC/CLIC CEPC-SPPC FCC HL-LHC Physics programs Summary FCC (80 km) CEPC-SPPC (50 km) (HL-)LHC (27 km) ILC (31 km) /CLIC (48 km) B-factories, muon collider, gamma-gamma collider and several other colliders are also very interesting but not discussed here. 3

4 International Linear Collider (ILC) e + e - linear collider with Superconducting RF linac Baseline: s = 500 GeV (31 km) upgrade later to ~ s= 1 TeV (50 km), luminosity of cm -2 s -1 with optional upgrade, one interaction point (IP) with two detectors: ILD and SiD with push-pull 4

5 ILC History Pre-ILC (several linear collider concepts since early 90s), technology decision in 2004 SCRF TESLA (SCRF) NLC/JLC (normal conducting) CLIC (two beam) ILC since 2005 Global Design Effort founded Reference Design Report (2007) Technical Design Report (2013) Current status Linear Collider Collaboration (LCC) ILC: Higgs/top factory possible realisation in Japan CLIC: multi-tev option on longer time scale TESLA TDR (2001) RDR (2007) TDR (2013) Waiting for the final decision from the Japanese government by the end of

6 Compact Linear Collider (CLIC) Drive Beam Main Beam Multi-TeV e + e - linear collider based on high gradient normal-conducting cavities with novel RF power generation (two-beam acceleration), nominal center-of-mass energy of 3 TeV Project not as advanced as ILC, possible Next Big Thing at CERN? 6

7 After the Higgs Discovery A bouquet of options: Higgs factory ideas bloom Courtesy of Symmetry Magazine 7

8 Circular Colliders The relative lightness of the discovered Higgs boson makes the circular electron-positron machine technologically feasible as Higgs Factory. A. Blondel and F. Zimmerman A High Luminosity e+e- Collider in the LHC tunnel to study the Higgs Boson, arxiv: LEP3 Super-TRISTAN, Fermilab Site-Filler, CHF, TLEP CEPC-SPPC FCC hh, ee, he ICFA Beam Dynamics Workshop Accelerators for a Higgs Factory: Linear vs. Circular November 14-16, 2012 Fermilab, Batavia, Illinois, U.S.A. ICFA Beam Dynamics Workshop, Accelerators for a Higgs Factory: Linear vs. Circular (HF2012) circular machines under official discussion ICFA 2013 statement: ICFA supports studies of energy frontier circular colliders and encourages global coordination. Factory γγ conferences.fnal.gov/hf2012 Organizing Committee: Local Committee: Contact: Alain Blondel, U.of Geneva Elliott McCrory, Fermilab Cynthia M. Sazama, Conference Office Alex Chao, SLAC Cynthia Sazama, Fermilab Fermi National Accelerator Laboratory Weiren Chou, Fermilab, Chair Tanja Waltrip, Fermilab M.S. 113, P.O. Box 500 Batavia, IL 60510, U.S.A. Jie Gao, IHEP Suzanne Weber, Fermilab Fax: sazama@fnal.gov Daniel Schulte, CERN Kaoru Yokoya, KEK 8

9 Circular Electron Positron Collider (CEPC) e+ IP1 e- LTB BTC e+ e- Linac BTC CEPC Booster IP3 CEPC Collider Ring Circular e + e - collider with conventional accelerator technologies proposed by the Chinese HEP community in 2012 Baseline design: s = 240 GeV (54 km), single ring with the pretzel scheme, luminosity of cm -2 s 240 GeV, 2 IP s; 10 years of data-taking Optional to operate at other energies: 91 GeV (Z-pole) and 160 GeV (WW) 9

10 Machine Layout 10

11 Possible Project Timeline CEPC Pre-studies ( ) R&D Engineering Design ( ) Construction ( ) Data taking ( ) 1 st Milestone: pre-cdr (by the end of 2014) R&D funding request to Chinese government in 2015 (China s 13 th Five-Year Plan ) Preliminary Conceptual Design Reports reviewed by international review committees and released: Volume I: Physics and Detector Volume II: Accelerator CEPC-SPPC Preliminary Conceptual Design Report Volume I - Physics & Detector IHEP-CEPC-DR IHEP-CEPC-DR IHEP-EP IHEP-AC IHEP-TH CEPC-SPPC Preliminary Conceptual Design Report Volume II - Accelerator Available on the CEPC website: The CEPC-SPPC Study Group March 2015 The CEPC-SPPC Study Group March

12 Detector Design Concept Feasibility studies based on the ILD-like detector concept, with modifications to the interaction region (IR) to cope with much shorter final focal length (L*) Final focusing magnets inside the detector constraints on detector layout and technology choice + backgrounds from backscattering particles Detector performance requirements (similar to ILC): Additional critical challenges: Detector/electronics power consumption (too short bunch crossing, powerpulsing not optional) Detector backgrounds detector occupancy, radiation damage, DAQ 12

13 Super Proton-Proton Collider (SPPC) SPPC HE Booster SPP ME Booster IP4 SPPC LE Booster Proton Linac IP2 pp collider after the electron machine in the same tunnel LEP-LHC model Baseline design : s = TeV, luminosity of cm -2 s -1 (different opinions on the required luminosity), 2 interaction points Main constraint: high field superconducting magnets, e.g. dipole magnets: 50 km: B = 20 T, E = 70 TeV SPPC Collider Ring B min 2 π( Bρ) = C 0 13

14 High Field Superconducting Magnets Nb 3 Sn + HTS Develop 12 T Nb 3 Sn double-aperture dipole magnet Conduct basic technology research on HTS materials and wires and prototype an inserted coil of 2 3 T R&D for 20 years Develop 15 T Nb 3 Sn double-aperture dipole/quadruple magnets Conduct basic technology research on HTS materials and wires and prototype an inserted coil of 4 5 T Develop Nb 3 Sn (15 T) + HTS (5 T) or HTS (20 T) dipole magnet Knowledge and experience transfer to industry, enabling mass production 14

15 Possible Project Timeline CEPC Pre-studies ( ) R&D Engineering Design ( ) Construction ( ) Data taking ( ) 1 st Milestone: pre-cdr (by the end of 2014) R&D funding request to Chinese government in 2015 (China s 13 th Five-Year Plan ) SppC R&D ( ) Engineering Design ( ) Construction ( ) Data taking ( ) Extremely tight schedule, close to unrealistic Possibility to operate both electron and proton machines at the same time to accumulate more Higgs events 15

16 Civil Engineering Detailed geological survey and conceptual design efforts of civil engineering, summarised in precdr volume III: Civil Engineering (only in Chinese) IHEP proton electron 16

17 Future Circular Collider (FCC) 100 TeV proton-proton (and heavy-ion) collider and a high luminosity e + e - collider (H, Z, W and tt ) as a potential intermediate step FCC hh, ee, he FCC-hh LHC Energy [TeV] Dipole field [T] # IP Luminosity [cm -2 s -1 ] Stored energy/beam [GJ] Synchrotron rad. [W/m/ aperture] Bunch spacing [ns] 25 (5) 25 17

18 M. Benedikt, FCC study overview and status in FCC Week

19 M. Benedikt, FCC study overview and status in FCC Week

20 M. Benedikt, FCC study overview and status in FCC Week

21 High Luminosity LHC HL-LHC expected around 2023 to cm -2 s -1 and to deliver an integrated luminosity of 3000 fb -1 to each experiment over 10 years ATLAS/CMS detectors to be upgraded/re-built to cope with the hash collision conditions yet to maintain/enhance the performance European Strategy: P5 Report: 21

22 Physics Programs (selected topics) 22

23 e + e - Colliders: Luminosity vs Energy 23

24 Higgs Measurements dominant process at s ~ 240 GeV Well-defined initial states model independent measurements M 2 recoil =(p s E ff ) 2 p 2 ff = s 2E ffp s + m 2 ff Recoil mass method: reconstructed the Z decay without touching the Higgs, allowing precision measurements: production cross sections, branching ratios, Higgs mass, total decay width and more 24

25 Higgs Couplings Higgs couplings to fermions and gauge bosons predicted by the Standard Model (SM): g(hff;sm) and g(hv V ;SM); deviations from the SM couplings parameterised as: apple f = g(hff) g(hff;sm), apple V = g(hv V ) g(hv V ;SM) Relative Error Model-dependent fit: Precision of Higgs coupling measurement (Contrained Fit) LHC 300/3000 fb -1 CEPC 250 GeV at 5 ab -1 wi/wo HL-LHC Relative Error Model-independent fit: Precision of Higgs coupling measurement (Model-IndependentFit) ILC GeV at fb -1 wi/wo HL-LHC CEPC 250 GeV at 5 ab -1 wi/wo HL-LHC 10-3 κ b κ c κ g κ W κ τ κ Z κ γ 10-3 κ b κ c κ g κ W κ τ κ Z κ γ κ μ Br(inv) κ Γ 25

26 Expected Precision 26

27 Higgs Self-coupling Critical parameter governing the dynamics of electroweak symmetry breaking; accessible via the loop correction to the hz Zh = Zh SM Zh 1=2 applez hhh 27

28 EW Precision Measurements EW precision measurements with significantly reduced uncertainties: R b,a b FB, sin eff W,m Z,m W,N R Ldt 150 fb 1 28

29 Electroweak Oblique Parameter Fit Electroweak parameters S and T, describing the gauge boson self-energies, are sensitive to physics beyond the Standard Model. Electroweak Fit: S and T Oblique Parameters 0.2 Current (95%) Current (68%) CEPC (95%) 0.1 CEPC (68%) Electroweak Fit: S and T Oblique Parameters 0.15 Current (68%) CEPC baseline (68%) 0.10 Improved Γ Z (68%) 0.05 Electroweak Fit: S and T Oblique Parameters CEPC baseline (68%) Improved Γ Z (68%) Improved Γ Z, m t (68%) T 0.0 T 0.00 T S S S 29

30 Higher Energies Precise determination of the top mass ( m t 100 MeV ) with the threshold scan method (350 GeV reachable at FCC-ee/ILC/CLIC ) Top-Higgs Yukawa coupling (500 GeV) accessible at ILC/CLIC with expected precision of g t /g t = 10% and Higgs-self coupling via e + e! t th 30

31 ILC/CEPC/FCC Complementary Higgs coupling measurements: considerable improvement in precision for bb, gg, cc, WW, τ + τ - and Γtot,+ top-higgs coupling, top mass by ILC ILC GeV with fb -1 CEPC 250 GeV with 5000 fb -1 ILC + CEPC Accelerator technologies (e.g. RF cavity) and detector technologies (vertex detector, calorimeter, etc. ) important to exploit the synergies 31

32 TeV Physics opportunities: Naturalness, Dark Matter, EW phase transition much extended searches with unprecedented high energy [TeV] 0 m χ gluino-neutralino with LF decays pp ~ g ~ g qq χ qq χ 5 σ discovery TeV, 3000 fb TeV, 3000 fb TeV, 3000 fb TeV, 300 fb [TeV] 0 1 χ m pp g ~ g ~ tt χ tt χ TeV, 140 PU, 3000 fb TeV, 140 PU, 3000 fb TeV, 140 PU, 3000 fb TeV, 50 PU, 300 fb m~ g [TeV] gluino-neutralino with HF decays 1 5 σ discovery m~ g [TeV] Waiting for more results/hints from the LHC 32

33 Summary ILC/CLIC, CEPC-SPPC and FCC: extraordinary physics potential precision measurements + search for New Physics Important to exploit the synergies between different projects (accelerator/detector/computing and more) Global Efforts FCC (80 km) CEPC-SPPC (50 km) (HL-)LHC (27 km) ILC (31 km) /CLIC (48 km) 33

34 Extra Slides 34

35 Cross-sections dominant process at the threshold e + Z H e Z e + ν e e + e + W H Z H W Z e e ν e e 35

36 CEPC-SPPC PreCDR International Reviews 36

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