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Lawrence’s 27-inch cyclotron, external beam ionizing air. R&D for Future Accelerators. Frank Zimmermann, CERN UPHUK3, Bodrum, 17 September 2007. We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6
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Lawrence’s 27-inch cyclotron, external beam ionizing air R&D for Future Accelerators Frank Zimmermann, CERN UPHUK3, Bodrum, 17 September 2007 We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6 "Structuring the European Research Area" programme (CARE, contract number RII3-CT-2003-506395)
outline introduction hadron colliders - LHC, LHC upgrade e+e- factories ep colliders b beams, n factories, & m colliders advanced acceleration concepts
“Livingston plot” of accelerator energy vs. time about a factor 10 increase every 6-8 years whenever one technology ran “out of steam” a new technology took over! can this trend continue? → accelerator R&D From W.K.H. Panofsky, “Evolution of Particle Accelerators and Colliders,” 1997
1st cyclotron by Ernest O. Lawrence & Stanley Livingston ~1930 diameter 4.5 inches (~11 cm) final proton energy 1.1 MeV “Dr Livingston has asked me to advise you that he has obtained 1,100,000 volt protons. He also suggested that I add ‘Whoopee’!” —Telegram to Lawrence, 3 August 1931
why higher energy? • quantum mechanics: de Broglie wavelength l=h/p → examining matter at smaller distance requires higher momentum particles • many of the particles of interest to particle physics are heavy →high-energy collisions are needed to create these particles
1st cyclotron, ~1930 E.O. Lawrence 11-cm diameter 1.1 MeV protons LHC, 2008 9-km diameter 7 TeV protons after ~80 years ~107 x more energy ~105 x larger
“optimistic scenario” plasma? lasers? future energy
hadron colliders Tevatron & RHIC are operating; LHC starts in 2008 R&D: Tevatron upgrades (4.3 MeV e-cooling!) RHIC upgrades (stochastic cooling, 54 MeV e-cooling, luminosity↑ x10; eRHIC) LHC upgrades (luminosity & energy)
Large Hadron Collider (LHC) proton-proton collider next energy-frontier discovery machine c.m. energy 14 TeV (7x Tevatron) design luminosity 1034 cm-2s-1 (~100x Tevatron) start of beam commissioning in 2008 LHC baseline luminosity was pushed in competition with SSC
three LHC challenges • collimation & machine protection - damage, quenches, cleaning efficiency, impedance • electron cloud - heat load, instabilities, emittance growth • beam-beam interaction -head-on, long-range, weak-strong, strong-strong
electron cloud in the LHC schematic of e- cloud build up in the arc beam pipe, due to photoemissionand secondary emission [F. Ruggiero]
long-range beam-beam 30 long-range collisions per IP, 120 in total
crossing angle “Piwinski angle” qc/2 luminosity reduction factor nominalLHC effective beam size s→s/Rf
stronger triplet magnets optional Q0 quad’s D0 dipole small-angle crab cavity ultimate bunches + near head-on collision LHC upgrade path 1: early separation (ES) • ultimate LHC beam (1.7x1011 protons/bunch, 25 spacing) • squeeze b* to ~10 cm in ATLAS & CMS • add early-separation dipoles in detectors starting at ~ 3 m from IP • possibly also add quadrupole-doublet inside detector at ~13 m from IP • and add crab cavities (fPiwinski~ 0) → new hardware inside ATLAS & CMS detectors, first hadron-beam crab cavities J.-P. Koutchouk
LHC upgrade path 2: large Piwinski angle (LPA) • double bunch spacing to 50 ns, longer & more intense bunches with fPiwinski~ 2 • b*~25 cm, do not add any elements inside detectors • long-range beam-beam wire compensation → novel operating regime for hadron colliders larger-aperture triplet magnets wire compensator fewer, long & intense bunches + nonzero crossing angle + wire compensation
luminosity for operation near beam-beam limit with alternating planes of crossing at two IPs ↑ LPA ↑ ES ↑↑ LPA ↑ LPA ↓ ES ↓ LPA ↓↓ ES ↓ LPA where (DQbb) = total beam-beam tune shift; peak luminosity with respect to “ultimate” LHC in two scenarios: “ES”: x 6 x 1.3 x 0.86 = 6.7 “LPA”: ½ x2 x2.9x1.3 x1.4 = 5.3 what matters is the integrated luminosity PAF/POFPA Meeting 20 November 2006
IP1& 5 luminosity evolution for ES and LPA scenarios ES LPA average luminosity initial luminosity peak may not be useful for physics (set up & tuning?) PAF/POFPA Meeting 20 November 2006
IP1& 5 event pile up for ES and LPA scenario LPA ES PAF/POFPA Meeting 20 November 2006
experiments prefer more constant luminosity, less pile up at the start of run, higher luminosity at end how could we achieve this? ES: dynamic b squeeze dynamic q change (either IP angle bumps or varying crab voltage) LPA: dynamic b squeeze, and/or dynamic reduction in bunch length luminosity leveling “equivalent” of top-up injection in e+e- colliders PAF/POFPA Meeting 20 November 2006
LHC injector upgrade • needed for ultimate LHC beam • reduced turn around time & higher integrated luminosity • 4x1011 protons spaced by 25 ns (now ~1.5 1011) • beam production under study (various options) • 3 techniques forbunch flatteningavailable PAF/POFPA Meeting 20 November 2006
CERN DG White Paper - LHC Injector Upgrade Proton flux / Beam power Linac4 Linac2 50 MeV 160 MeV PSB SPL’ RCPSB SPL 1.4 GeV ~ 5 GeV PS Linac4: PSB injector (160 MeV) SPL: Superconducting Proton Linac (~ 5 GeV) SPL’: RCPSB injector (0.16 to 0.4-1 GeV) RCPSB: Rapid Cycling PSB (0.4-1 to ~ 5 GeV) PS2: High Energy PS (~ 5 to 50 GeV – 0.3 Hz) PS2+:Superconducting PS (~ 5 to 50 GeV – 0.3 Hz) SPS+: Superconducting SPS (50 to1000 GeV) DLHC: “Double energy” LHC (1 to ~14 TeV) 26 GeV PS2 (PS2+) 40 – 60 GeV Output energy SPS SPS+ 450 GeV 1 TeV LHC DLHC 7 TeV ~ 14 TeV M. Benedikt, R. Garoby, CERN DG
ultimate LHC “upgrade”: higher beam energy 7 TeV→14 (21) TeV? → R&D on stronger magnets proof-of principle & world record: 16 T at 4.2 K at LBNL (in 10 mm aperture), 2001. (S. Gourlay)
proposed design of 24-T block-coil dipole for LHCenergy tripler P. McIntyre, Texas A&M, PAC’05 magnets are getting more efficient!
e+e- colliders • VEPP-2000, 1x1 GeV; starting 2007? • DAFNE upgrade, 1x1 GeV; 2007 • … BEPC-II, CESR-c, PEP-II … • Super t-charm factory , 1x3.5 GeV, 2015? • KEKB→SuperKEKB, 3.5x8 GeV, ~2010 • SuperB, 4x7 GeV, ~2010 • ILC, 0.25x0.25 TeV, ~2020? • CLIC, 0.5x0.5 TeV→2.5x2.5 TeV, ~2023?
DAFNE-upgrade: crab waist collisions M. Biagini, P. Raimondi, M. Zobov, et al like LHC LPA like LHC ES New!
P. Raimondi, M. Zobov, et al
KEKB : crab crossing since 02/07 K. Oide
8GeV Positron beam 4.1 A 3.5GeV Electron beam 9.4 A higher beam currents smaller by*/smaller sz increased xy Super B Factory at KEK
&/or SuperB & TAC SuperKEKB SuperB (Frascati)? ? TAC VEPP-2000
TAC Turkic Accelerator Complex e- linac e+ storage ring S. Sultansoy et al linac-ring tau-charm-phi factory with L>1034 cm-2s-1, completion ~2015
LHC-based ep collider(s) QCDE LHC CMS LHC-B ALICE ATLAS LEP-3 ILC-1
pe collider based on LHC H. Aksakal S. Chattophadyay D. Schulte S. Sultansoy F. Zimmermann, et al F. Willeke J. Dainton M. Klein et al
Linear Collider R&D • damping-ring prototype ATF at KEK achieves world’s smallest emittance beams; pioneered numerous diagnostics developments (laser wires, diffraction radiation, X-ray optics, interferometry, …) tuning & correction schemes trains young generation of accelerator physicists • final focus ATF-2 truly international project uses low-emittance beam extracted from ATF ring aims to produce 30 nm spot size with less than 5% orbit “jitter” test of diagnostics (nm-BPMs, spot-size monitors) test of feedbacks & stabilization schemes • polarized e+ source via Compton back-scattering (PosiPol collaboration)
Accelerator Test Facility H. Hayano Damping ring ATF is the largest LC Test Facility E=1.28GeV Ne=1x1010 e-/bunch 1 ~ 20 bunches Rep=1.5Hz X emit=2.5E-6 mm ( at 0 intensity) Y emit=2.5E-8 mm ( at 0 intensity) ~ ILC emittance requirements Linac
ATF demonstrated single bunch emittance gex~3.5-4.3 mm (1.4-1.7 nm) gey~13-18 nm (5-7 pm) at 8x109 e-/bunch CLIC target values gex~0.45 mm gey~3 nm at 2.5x109 e-/bunch ?
polarized e+/e- source based on laser Compton back scattering • highly polarized e+ and e- (>90%); • fully independent e+ generation M. Kuriki, T. Omori, J. Urakawa, KEK K. Moenig, A. Variola, F. Zomer, LAL E. Bulyak, P. Gladkikh, NSC KIPT version 1: Compton e- ring
polarized e+/e- source based on laser Compton back scattering M. Kuriki, T. Omori, J. Urakawa, KEK K. Moenig, A. Variola, F. Zomer, LAL E. Bulyak, P. Gladkikh, NSC KIPT • highly polarized e+ and e- (>90%); • fully independent e+ generation version 2: Compton ERL
www of PosiPol R&D TAC M. Kuriki
n factory: generic layout high-power proton source 24-GeV BNL AGS upgraded to 1-4 MW p beam power target Hg gas jet in 20-T solenoid cooling solid LiH absorbers; closed cavity aperture fast accelerations.c. linac, RLA, 2 non-scaling FFAGs decay storage ring D. Kaplan
n-factory demonstration experiments targetry: mercury jet with 20 m/s speed will be tested in 15-T solenoid at CERN (nTOF11); instantaneous power deposition of 180 J/g ~ 4-MW p driver (2) cooling: ionization cooling experiment MICE at RAL;two solenoid tracking spectrometers; 2nd phase: one lattice cell of cooling channel installed between spectrometers; expected emittance reduction ~ 10% (3) acceleration: “scaling” or “non-scaling” fixed- field alternating gradient synchotrons (FFAGs)
Recorded at 4kHz Replay at 20 Hz BNL AGS Proton beam 1 cm Hg jet v=2 m/s Proton beam on mercury Jet • Fabich • et al.
Recorded at 4kHz Replay at 20 Hz BNL AGS Proton beam 1 cm Hg jet v=2 m/s proton beam on mercury jet Splash velocity max. 50 m/s • Fabich • et al.
b beams • physics goals similar to n factory; b decay instead of m’s • nuclei that decay fast through atomic e- capture • (150Dy, 146Gd, etc.) →mono-energetic n beams • neutrino energy is Lorentz boosted: E=2gE0 • it is assumed that 1018n’s per year can be obtained, • e.g., at EURISOL -can profit from LHC injector upgrade! schematic of the proposed CERN part of a “CERN to Frejus” (130 km) EC n beam facility [J. Bernabeu et al.] alternative to n factory
“table top” ion storage ring with ionization cooling producing intense beam of radioactive ions e.g., 1014 Li-8 ions/s applications: b beams, hadron therapy cooling & production C.Rubbia A.Ferrari Y. Kadi V.Vlachoudis 2006 circumference 4 m, kinetic energy 27 MeV rf voltage 300 kV
m collider R. Johnson, Y. Derbenev et al. low emittance from improved ionization cooling techniques 5 TeV: ~5 X 2.5 km footprint, 5-km total linac length high L from small emittance! 1/10 fewer muons than originally imagined: a) easier p driver, targetry b) less detector background c) less site boundary radiation At 2.5 TeV beam energy After: Precooling Basic HCC 6D Parametric-resonance IC Reverse Emittance Exchange εN tr εN long. 20,000 µm 10,000 µm 200 µm 100 µm 25 µm 100 µm 2 µm 2 cm 2.5 TeV / beam: 20 Hz Operation:
plasma acceleration 2004 breakthrough in beam quality from laser- plasma acceleration next step: 1 GeV compact module, 100 TW laser, & plasma channel; LBNL, Strathclyde, Oxford, Paris J. Faure et al., C. Geddes et al., S. Mangles et al. , 3 articles in Nature 30 September 2004
principle: plasma can sustain high accelerating gradients ~10-100 GV/m plasma excitation by laser plasma excitation by drive bunch P. Muggli W. Lu, B. Cros