1. Higgs Factories based on: - LEP3 circular e  e  machine - SAPPHIRE  collider Mayda M. Velasco Northwestern University BNL Seminar -- Jan. 17, 2013

2. Higgs Discovery in July 2012 H  WW H  bb H  ZZ …and what we know today

3. “Rich” mass region Already measuring its characteristics Mass from  plus ZZ  4L* – M = 125.8 ± 0.4 (stat) ± 0.4 (syst) Parity – 0 + : Scalar hypothesis consistent at a 0.6  level* – 0 - : Pseudo scalar hypothesis excluded at 2.5  level* Coupling – To both bosons and fermions Spin – No sensitivity yet to separate between Spin 0 & Spin 2  However, some argue that the observed rate is an indication that is not a spin 2 object Access to Higgs partial widths of to Bosons and Fermions * CMS based… Similar at ATLAS

4. What we should know by 2022?

5. So, what is next? Low Energy Higgs Factory Concepts Some examples of measurements needed after the LH C: Today… discussed two types of factories that could do the job! Continue to characterize the state – Coupling to the top quark – Self couplings – Total width Need to evaluate (new physics) lo op induced effects – Hgg, H , HZ  – Precision electroweak measurements – Precision mass measurements (W, Z, top,...) Need to determine the (tree level) structure of the theory – Invisible Higgs decays, Exotic Higgs d ecays? – CP mixing and violations?

6. LEP3 AND TLEP  LOW ENERGY CIRCULAR e  e  MACHINES

7. LEP3 and TLEP -- e+e- ring PSB PS (0.6 km) SPS (6.9 km) LHC (26.7 km) LEP3 (e + e -, 240 GeV c.m.) In the LHC tunnel (LEP3) or a new tunnel (TLEP) Instantaneous luminosity larger than 10 34 / s/cm 2 at maximum energy Larger at smaller energies Delivered in 2 or 4 interaction points  ATLAS and CMS in LEP3 TLEP (80 km, e + e - ~350 GeV c.m.) VHE-LHC ( later… pp, 100 TeV c.m.)

8. The two options Installation in the LHC tunnel “LEP3” inexpensive (<0.1 x LC) tunnel exists reusing ATLAS and CMS detectors reusing LHC cryoplants  interference with LHC and HL-LHC New larger tunnel “TLEP” higher energy reach, (5-10)x 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  (4-5)x more expensive (new tunnel, cryoplants, detectors)

9. LHC tunnel cross section with space reserved for a future lepton machine like LEP3 [blue box above the LHC magnet] and with the presently proposed location of the LHeC ring [red] Putting LEP3 into the LHC tunnel?

10. «Pre-Feasibility Study for an 80-km tunnel at CERN» John Osborne and Caroline Waaijer, CERN, ARUP & GADZ, submitted to ESPG TLEP tunnel in the Geneva area – “best” option

11. LEP3 and TLEP LEP3TLEP circumference26.7 km80 km max beam energy120 GeV175 GeV max no. of IPs44 Lum. 350 GeV c.m.-0.7x10 34 cm -2 s -1 Lum. 240 GeV c.m.10 34 cm -2 s -1 5x10 34 cm -2 s -1 Lum. 160 GeV c.m.5x10 34 cm -2 s -1 2.5x10 35 cm -2 s -1 Lum. 90 GeV c.m.2x10 35 cm -2 s -1 10 36 cm -2 s -1 ee  tt ee  ZH ee  WW ee  Z Basic parameters:

12. Beam Lifetime LEP2: beam lifetime ~ 6 h dominated by radiative Bhabha scattering with cross section  ~ 0.215 barn LEP3 with L~10 34 cm −2 s −1 at each of several IPs:  beam,LEP3 ~18 minutes from rad. Bhabha scattering → solution: top-up injection Beam lifetime also limited due to beamstrahlung, but can be compensated for using: (1) large momentum acceptance (h ≥ 3%), and/or (2) flat(ter) beams and/or (3) fast replenishing

13. Example: Top-up injection at PEP-II/BaBar Before Top-Up Injection After Top-Up Injection

14. arc optics same as for LHeC:  x,LHeC <1/3  x,LEP1.5 at equal beam energy, optical structure compatible with present LHC machine (not optimum!) small momentum compaction (short bunch length) assume  y /  x ~5x10 -3 similar to LEP (ultimate limit  y ~ 1 fm from opening angle) RF RF frequency 1.3 GHz or 700 MHz ILC/ESS-type RF cavities high gradient (20 MV/m assumed, 2.5 times LEP gradient) total RF length for LEP3 at 120 GeV similar to LEP at 104.5 GeV short bunch length (small  * y ) cryo power ≤LHC synchrotron radiation energy loss / turn: E loss [GeV]=88.5×10 −6 (E b [GeV]) 4 /ρ[m]. higher energy loss than necessary arc dipole field = 0.153 T compact magnet critical photon energy = 1.4 MeV 50 MW/beam (total wall plug power ~200 MW ~ LHC complex)→4x10 12 e ± /beam Other LEP3 parameters

15. LEP3 as Higgs Factory Higgs-strahlung is main production process: HZZ coupling observed at the LHC Vector boson fusion give small contribution Reasonable background level M H =125 GeV

16. Higgs measurements at LEP3 (√s = 240 GeV)

17. Other Higgs measurements at LEP3(√s = 240 GeV)

18. TLEP Physics program Same as LEP3… Less synchrotron radiation and … – five times more luminosity at √s = 240 GeV – 2 to 5 times more luminosity at √s = m Z or 2m W Top physics at √s = 350 GeV – precision top mass measurement

19. Linear versus Circular e  e   5 Years

20. Beamstrahlung much more benign than for linear collider; LEP3/TLEP are clean machines Beamstrahlung much more benign than for linear collider; LEP3/TLEP are clean machines Comment: Beamstrahlung effect at LEP3 much smaller than for ILC

21. Linear versus Circular e  e 

22. Other precision measurements

23. LEP3 could open a whole new era in EW precision measurements M H =215 GeV

24. Summary: Summary: Low energy e  e   Higgs Factories (ILC 250, 350, LEP3, TLEP) TLEP Peskin

25. Only discussed: LEP3 and TLEP (& ILC), but many more options for circular e + e - Higgs factories are becoming popular around the world LEP3 2011 SuperTristan 2012 LEP3 on LI, 2012 LEP3 in Texas, 2012 FNAL site filler, 2012 West Coast design, 2012 Chinese Higgs Factory, 2012 UNK Higgs Factory, 2012

26. SAPPHIRE  LOW ENERGY HIGGS FACTORY BASED ON PHOTON-PHOTON COLLISIONS SAPPHiRE & LHeC cern.ch/accnet

27. Combining photon science & particle physics!  collider based on e - e -  laser : Pulses of a several Joules with a ~350nm (3.53 eV) for E e- ~ 80 GeV Compton scattering: e −   laser → e −  can transfer  of e- energy to 

28. e-e-, e-  and  colliders – Higgs produced in s-channel (low ee CoM) – Starts from e  e  therefore, both beam can be highly polarized – Laser or FEL needed to generate high  -beam (e −   laser → e −  ) are now available Opportunity to work with technology, that is of interest to other fields of basic science and industry – Compact machine: less that 10 Km in diameter Fits in various national labs – “Low cost”

29. e  e    Spectrum tuned for Higgs

30. Photon beam polarization  : H production in   H

31. Cross sections convoluted with the expected beam profile      

32. Circularly polarized laser Linearly polarized laser

33. Only with  C == 0 if CP is conserved In s-channel production of Higgs: == +1 (-1) for CP is conserved for A CP-Even (CP-Odd) Higgs If A 1 ≠0, A 2 ≠0 and/or | A 3 | < 1, the Higgs is a mixture of CP-Even and CP-Odd states Possible to search for CP violation in gg  H  fermions without having to measure their polarization In bb, a ≤1% asymmetry can be measure with 100 fb -1 that is, in 1/2 years arXiv:0705.1089v2

34. This is why we should consider a low energy  collider, like SAPPHIRE, as a Higgs Factory unexpected Search for the unexpected properties of the Higgs in a model independent way… That is, Higgs CP Mixing and Violations CP asymmetries at the 1% level or better will be accessible with current designs by taking advantage of both linear and circular polarization

35. SAPPHiRE SAPPHiRE: Small Accelerator for Photon-Photon Higgs production using Recirculating Electrons Scale ~ European XFEL, About 20k Higgs per year

36. Energy loss of multiple passes beam energy [ GeV]  E arc [GeV]  E [MeV] 100.00060.038 200.0090.43 300.051.7 400.155.0 500.3610 600.7520 701.3935 801.1927 total3.8957 (0.071%) 

37. Prototype arc magnets LHeC dipole models (BINP & CERN) eRHIC dipole model (BNL) 5 mm gap max. field 0.43 T (30 GeV) 25 mm gap max. field 0.264 T (60 GeV)

38. SAPPHiREsymbolvalue total electric powerP100 MW beam energyE80 GeV beam polarizationPePe 0.80 bunch populationNbNb10 repetition ratef rep 200 kHz bunch length zz 30  m crossing angle cc ≥20 mrad normalized horizontal/vert. emittance  x,y 5,0.5  m horizontal IP beta function x*x* 5 mm vertical IP beta function y*y* 0.1 mm horizontal rms IP spot size x*x* 400 nm vertical rms IP spot size y*y* 18 nm horizontal rms CP spot size  x CP 400 nm vertical rms CP spot size  y CP 440 nm e - e - geometric luminosityL ee 2x10 34 cm -2 s -1

39. Luminosity spectra for SAPPHiRE as functions of E CM (  ), for 3 possible normalized distances  ≡l CP-IP /(  y *) (left) and different polarizations of in-coming e- &  (right) SAPPHiRE  luminosity

40. 5 Linacs IP 2 Linacs Top Energy80 GeV Turns34 Magnet ρ644.75 m706.65 m Linacs (5)5.59GeV4.23GeV δp/p6.99x10 -4 7.2x10 -4 ϵ nx Growth1.7μm1.8μm Top Energy80 GeV Turns45 Avg. Mag. ρ661.9 m701.1 m Linacs (2)10.68GeV8.64GeV δp/p8.84x10 -4 8.95x10 -4 ϵ nx Growth2.8μm2.85μm 1) 2) Possible Configurations at FNAL

41. Possible Configurations at JLAB 85 GeV Electron energy γ c.o.m. 141 GeV 103 GeV Electron energy γ c.o.m. 170 GeV Edward Nissen Town Hall meeting Dec 19 2011

42. Ex. of physics program relevant to our understanding of Higgs that will be accessible with SAPPHIRE e  e  ---> sin 2  W (running) e   ---> M W  to H –    g ttH –  Total – CP mixing and violation in a model independent way from both g Hff and g HVV

43. e  e  : Moller Scattering to get running of sin 2  W >  barn Should we aim at higher ee E cm ? Currently 160 GeV

44. e   : M W from e     W  Mass measurement from W  hadron events Or from energy scan

45.   - channel e    e      

46.     = 30% at ILC after 5 years

47. %2 Measurement of   %10 Measurement of  Total Assuming that we know  Br(h  bb) ~2% Only with  C  4% constraint in ttH Yukawa coupling

48. Low energy  colliders This machine will be crucial to study the CP mixing and violation in the Higgs sector Using the e-e- component of the beam, we could not only make precise measurements of the running of sin 2  W, but also: – Majorana neutrinos by searching for e  e   W  W  Many more physics topics that go well beyond Higgs – Tau Tau factory … good to study g-2 of the  lepton – Quark structure of the photon, etc.

49. Conclusions LEP3 and SAPPHIRE may some of the cheapest possible option to study the Higgs (cost ~1B scale), feasible, ee component “off the shelf”, but perhaps not easy TLEP is more expensive (~5 BEuro?), but clearly superior in terms of energy & luminosity, and extendable towards VHE-LHC, preparing ≥50 years of exciting e + e -, pp, ep/A physics at highest energies SAPPHiRE matches infrastructure, expertise & sites of many HEP or former or future HEP laboratories (JLAB, SLAC, KEK, FNAL, BNL, DESY,…)

50. BACKUP

51. SAPPHiRE DAY 19 February 2013 1.Physics case: Theory, John Ellis / King’s College 2.Physics case: Experiment, Mayda Velasco / Northwestern U. 3.Machine concept & options – Frank Zimmermann / CERN 4.Luminosity calculations (?) – Marco Zanetti / MIT Or Daniel Schulte / CERN 5.Commercial lasers & future extrapolation - Laura Corner / JAI 6.R&D status for gamma-ray and X-ray generation based on Compton scattering at KEK, Junji Urakawa / KEK 7.Feedback R&D for Optical Cavity, Hiroshima U. 8.Compton collision scheme of the EGAMMAS Proposal for ELI-NP, Luca Serafini /INFN-Milano 9.Optical cavity & IR design for gamma-gamma collider, Klaus Moenig/DESY 10.High finesse multi-mirror optical cavity w feedback, Fabian Zomer/LAL 11.LAL Compton collisions and Thom-X project, Alessandro Variola/LAL 12.Duke FEL-Compton scheme and outlook, Vladimir Litvinenko/BNL 13.High average power femtosecond laser technology, Marc Hanna/Institut d'Optique Palaiseau 14.Current status and future of high-power ultrafast industrial lasers, Yoann Zaouter/Amplitude Systemes 15.Extrapolating Current Laser Technology for a SAPPHiRE Laser System, Jeff Gronberg/LLNL 16.Gamma-gamma & Compton studies at FACET-2, Vitaly Yakimenko/SLAC

54. Self-generated FEL  beams (instead of laser )? optical cavity mirrors wiggler converting some e - energy into photons ( ≈350 nm) e - (80 GeV) e - (80 GeV) Compton conversion point  IP e - bend example: u =200 cm, B=0.625 T, L u =100 m, U 0,SR =0.16 GeV, 0.1%P beam ≈25 kW “intracavity powers at MW levels are perfectly reasonable” – D. Douglas, 23 August 2012 scheme developed with Z. Huang

55. Source: Fiber lasers and amplifiers: an ultrafast performance evolution, Jens Limpert, Thomas Schreiber, and Andreas Tünnermann, Applied Optics, Vol. 49, No. 25 (2010) power evolution of cw double-clad fiber lasers with diffraction limited beam quality over the past decade: factor 100 increase! laser progress: example fiber lasers

56. LAL MightyLaser experiment at KEK-ATF non-planar high finesse four mirror Fabry-Perot cavity; first Compton collisions observed in October 2010 I. Chaikovska, N. Delerue, A. Variola, F. Zomer et al Comparison of measured and simulated gamma-ray energy spectra from Compton scattering Gamma ray spectrum for different FPC stored laser power Vacuum vessel for Fabry-Perot cavity installed at ATF Optical system used for laser power amplification and to inject laser into FPC Plan: improve laser and FPC mirrors & gain several orders I. Chaikovska, PhD thesis to be published