Large Hadron Electron Collider - Particle PhysicsLarge Hadron Electron Collider Progress Report to...
Transcript of Large Hadron Electron Collider - Particle PhysicsLarge Hadron Electron Collider Progress Report to...
LargeHadronElectronColliderProgressReporttoECFA
MaxKlein
fortheLHeCGroup
ECFAatCERNGeneva27.November2009
www.lhec.cern.ch
Electron-Nucleon Scattering
at the Tera ScaleCERN-ECFA-NuPECC: Preparing a Conceptual Design Report on the LHeC
The Large Hadron Electron Collider (LHeC) is a new colliding beam facility, based on the LHC at CERN, exploiting Tera scale cms energies in the electron-quark system in order to pursue a rich and luminous programme of inelastic, polarised electron/positron -proton, deuteron and heavy ion scattering measurements. By reaching momentum transfer squared values of Q2 above 106 GeV2 and correspondingly low values of Bjorken x, the LHeC is seen as a natural complement to the LHC and to an envisaged new lepton collider. This poster illustrates part of the still ongoing work on the machine, interaction region and detector designs as well as on the
physics potential of the LHeC at high scales, high parton densities and with high precision eq measurements. This work, pursued in a wide international collaboration under the auspices of CERN, ECFA, NuPECC and a Scientific Advisory Committee, is directed to a Conceptual Design Report by 2010, as part of the deliberations of the HEP community on its future programme of exploring the energy frontier with accelerators, which is reminiscent to the exploration of the Fermi scale with HERA, the Tevatron and LEP. More information on the LHeC is collected at www.lhec.org.uk. The next workshop will be held at Divonne 1-3.9.2009.
LHeC Physics and Kinematics - Kinematic plane in Bjorken-x and resolving power Q2 , showing the coverage of fixed-target experiments, HERA and the LHeC. The mapping of the planned physics programme onto this plane is also indicated.
Direct Measurement of Partons - The LHeC permits the complete resolution of the light and heavy quark structure of the nucleon. It will make precision measurements of the beauty density, the first ever measurements of strange and anti-strange quark densities or the u/d densities at low and at large x . The LHeC is a single top and anti-top-quark factory.
LHeC as Ring-Ring Collider - The LHeC as a Ring-Ring Collider may use the SPL as an injector and will have bypasses around LHC experiments, in which the rf may be placed. A new type of dipole magnet is considered for installation on top of the proton ring. The luminosity is estimated to be above 1033cm-2s-1 with an assumed limit of 100 MV wall plug power.
Saturation of Parton Densities - At small Bjorken x the rise of the parton densities is predicted to be limited by unitarity. A new phase of matter appears governed by modified parton dynamics with relations to nuclear and neutrino astrophysics. This may be discovered in ep with precision measurements of F2 and FL , vector meson measurements or di!ractive scattering in a hitherto unexplored range of phase space and phenomena.
Lepton-Proton Scattering - Comparison of the energies and luminosities of selected previous (blue) and proposed future (red) lepton–proton scattering facilities. The LHeC moves DIS into the Terascale with about 100 times the luminosity of HERA.
Complementing the LHC - The LHeC complements the LHC with precision measurements e.g. on the gluon density or the investigation of the Higgs. With the LHeC, new physics phenomena possibly occurring at the LHC can be distinguished reliably from mere variations of partonic behaviour, currently subject to extrapolation and parameterisation uncertainties.
A New Detector for ep/eA - The detector is modular for fast installation down the pit and to cope with the requirements of high luminosity and of large acceptance near the beam axis. Design work is ongoing on the interaction region to allow for simultaneous operation of pp (LHC) and ep (LHeC) beams.
New Physics in eq Scattering - Singly produced new states, such as eq resonances or excited leptons, have a much higher cross section at an ep machine than in pp, which will allow the determination of quantum numbers of new states and possibly give access to a complementary phase space. If leptons and hadrons are ‘one form of matter’ (A.Salam), an eq collider is most suited for its exploration.
Resolving Proton’s Structure - Distance scales resolved in successive lepton–hadron scattering experiments since the 1950s, and some of the new physics revealed. The LHeC will resolve distances below 10-19m, more than a 10.000 times smaller than the proton’s radius and 10 times below HERA.
Exploring Multi-TeV Scales - Exploration of ultrahigh energy scales with precision measurements in electroweak and strong interactions. Precision determination of light quark weak neutral current couplings.Unification of coupling constants at the Planck scale may be tested with alpha_s measured an order of magnitude more accurately than so far.
LHeC as Linac-Ring Collider - The LHeC as a Linac-Ring Collider is considered to possibly use a racetrack arrangement of ILC type superconducting cavities. The luminosity is in excess of 1032cm-2s-1 with a power limit of 100MW, based on the sLHC upgrade. It may be enlarged with energy recovery techniques. The luminosity diminishes as 1/E with the electron beam energy and the linac may therefore surpass the energy reach of the ring.
Partonic Structure of Nuclei - The LHeC extends the experimental knowledge on the partonic structure of nuclei by nearly 4 orders of magnitude in DIS. The predicted enhancement of the gluon density ~A1/3 and the very high energies at the LHeC allow parton saturation e!ects to be studied both in ep and eA interactions and thus to uniquely separate nuclear from unitarity e!ects in deep inelastic scattering.
Compiled by M.Klein and F.Marcastel - 10 July 09
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=758 GeV)s (LHeC: e=1.4 TeV)s (LHeC: e=1.9 TeV)s (LHeC: e
LEPHERA: all channels
+eeLHC: e
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LHeCeRHIC
Fixed-target data:NMCE772E139E665EMC
(Au, b=0 fm)2sQ
perturbative
non-perturbative
(70 GeV - 2.5 TeV)
(10 GeV - 100 GeV)
e-Pb (LHeC)
e-Au (eRHIC)
PosteratEPS09andLepton‐Photon09
Kinema8csandRecentDevelopments
2008
SeptemberDivonneworkshop;NuPECCMeeKngatGlasgow
OctoberICFASeminaratSLAC
NovemberECFAPlenaryatCERN
DecemberConvenor’sMeeKngatCERN
2009
MarchVisittoSLAC[Linac]
AprilDIS09atMadrid:LHeCpremeeKng,parallel,SACplenarypanel(M.K.arXiv:0908.2877[hep‐ex])
AprilPAC09atVancouver‐Papers,Talk,Proceedings
MayVisittoBINPNovosibirsk[RingMagnets]
JuneLowx/HPDmeeKngatCERN,pre‐Blois
SeptemberDivonneII(CERN‐ECFA‐NuPECCWorkshop)~80talksfrom~100parKcipants
OctoberNuPECCLongRangePlanningWorkshop
CDRExtendedversionbyMidDecember09
PhysicsProgrammeoftheLHeC
+Unfoldingcompletelythepartonstructureoftheproton(andoftheneutronandphoton)andsearchforsub‐substructuredownto610‐20m
+ExploraKonofnewsymmetriesandthegrandunifica8onofparKcleinteracKonswithelectroweakandstronginteracKonmeasurementsofunprecedentedprecision.
+SearchforandexploraKonofnew,Terascalephysics,inparKcularfornewstateswithleptonqu.numbers(RPVSUSY,LQ,excitedfermions),complementarytotheLHC
+ExploraKonofhighdensitymaPer[lowxphysicsbeyondtheexpectedunitaritylimitforthegrowthofthenucleongluondensity]
+UnfoldingthesubstructureandpartondynamicsinsidenucleibyanextensionofthekinemaKcrangebyfourordersofmagnitude[iniKalstateoftheQGP]
Largeamountofstudiesdoneandongoing,withoutaimingatcompletelist.Followsanexampleperpointeach.Notethatthesearefinalwhenwriienup.
StrangeandAn8‐StrangeQuarkDistribu8ons
€
W −sbar→ cbar1 fb−1
εc = 0.1εq = 0.01δsyst = 0.1
−ϑ h ≥1o
•−ϑ h ≥10o
NotmeasuredwithH1,ZEUSHERMES(NK):smuchlarger?Dimuondata:s≠sbar?
W,ZsensiKvetos
LHeC:measurebothstrangeandan8‐swithhighprecisionforthefirst8me
HER
MES,K.Rith
EPS09
Q2~1GeV2
HighPrecisionElectroweakPhysics
Precisionmeasurementofweakneutralcurrentcouplings(+pdf’s):accesstonewelectroweakphysics.
40TeVlimitsonContactInterac8onsandcorrespondinglyonextradimensions
Gluon‐SMHiggs
InSMHiggsproduc8onisgluondominated
LHeC:hugex,Q2rangeforxgdetermina8on
WWtoHiggsfusionhassizeableepxsec8on
CTEQBelyayevetal.JHEP0601:069,2006
CfDivonne09forQCDbgdstudies+btagging
Beauty‐MSSMHiggs
InMSSMHiggsproduc8onisbdominated
FirstmeasurementofbatHERAcanbeturnedtoprecisionmeasurement.
LHeC:higherfrac8onofb,largerrange,smallerbeamspot,bePerSidetectors
CTEQBelyayevetal.JHEP0601:069,2006
DiscoveryofPartonSatura8on–ep,lowx
Fullsimula8onofF2andFLBothtogethermustrevealsatura8on
NuclearStructureandDynamics
ExtensionofQ2,1/xrangeby104
FermimoKon‐‐ptaggingShadowing‐‐diffracKon
p,D,Ca,Pbbeams
Completedetermina8onofnPDFsintononlinearregimeLHeCisboundtodiscoverpartonsatura8onineAANDep
AcceleratorandDetectorDesign
CollaboraKonsofCERNwithexpertsfromCockcrop,BNL,DESY,KEKLausanne,Novosibirsk,SLAC,TAC
20workpackageswithidenKfiedresponsibles
Ring‐Ringep/eA
Ee=10…70GeV.Lep~1033cm‐2s‐1(100KmesHERA)
Injector:dedicatedorSPLbased.
DetailedfirstdesignstudyinJINSTP1001(2006)
RRLuminosityandParameters
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€
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4
Luminosityfore±psafelyabove1033cm‐2s‐1
Used“ul8mate”LHCbeamparameters
Energylimitedbyinjec8onandsyn.radlosses
Powerlimitsetto100MW
Smallptuneshie:simultaneousppandep
eRing–Op8cs
βfuncKonsforLHeC‐2008
Dispersionwas50‐90cm
andhoriz.emiiance22nm
38460mlongcells
2009:opKmisaKonofFODOcell
Dispersionreducedto20‐50cm
emiianceεx=7.5nmεy=3.7nm
MEDIUMorWEAKBENDSOLUTION
“inner”tripletfocusβx=7.1cmβy=12.7cm
Op8csinthearcs
Op8misa8onongoing
Minibetadesign
DipoleMagnets
LEP
O‐shapedmagnetwithferritecore[BINP‐CERN] PrototypedesignunderwayatNovosibirsk,May2010
Accelerator LEP LHeC
CrossSec8on/cm2 50x50 20x10
Magne8cfield/T 0.02‐0.11 0.02‐0.135
EnergyRange/GeV 20‐100 10‐70
GoodFieldArea/cm2 5.9x5.9 6x3.8
FODOlength/m 76 53
Magnetlength/m 2x34.5 2x14.76
segmenta8on 6cores 14
Numberofmagnets 736 488
Weight/kg/m 800 240
Ring–Workinprogress
Interac8onregiondesign
Installa8onstudy
SystemaKcinvesKgaKonofclasheswithLHCinstallaKonandpossibleways‘around’
InstallaKonsequence‐Kmeline
Polarisa8on
TwoLINACConfigura8ons[CERN‐SLAC]
60GeV31MV/m,pulsedtwopasses
60GeV13MV/mCWERL4passes
140GeV31MV/m,pulsed2passes
LINAC‐RingParameters
€
Np =1.7 ⋅1011,εp = 3.8µm,β* = 0.2m,γ = 7000 /0.94
L = 8 ⋅1031cm−2s−1 ⋅Np10
−11
1.7⋅0.2β* /m
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4 1.9 2
gradientMV/m 32 13 32
normalisedε/μm 50 50 100
cryopower/MW 3 20 6
effecKvebeampower/MW
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TheLRcombinaKonyetrequiresasKllbeierpbeamor/andEerecoverytocometoluminositybeyond1032cm‐2s‐1
eOp8csforLINAC
2passes 4passes‐ERL
βx,yβx,y
LINAC‐WorkinProgress
IROp8ons:
Headondipoles
CrossinglikeRRIR
Positronsource
Difficulttoreachhighintensity.Perhapsbestsuited:hybridtargetproducKonofunpolarisedpositrons.SeveralstaKons?cfDivonne
LHeCDetectorversionforlowxandeAMuonchambers(fwd,bwd,central)
Coil(r=3ml=11.8m,3.5T)[ReturnFenotdrawn,2coilsw/oreturnFestudied]
CentralDetectorPixelsEllipKcbeampipe(~3cm‐orsmaller)
Silicon(fwd/bwd+central)[Stripor/andGasonSlimmedSiPixels][0.6mradiusfor0.03%*ptin3.5Tfield]
El.magn.Calo(Pb,Scint.9‐12X0)HadronicCalo(Fe/LAr;Cu/Brass‐Scint.~30λ)
FwdDetectors(downto1o)SiliconTracker[Pix/Strip/Strixel/PadSiliconor/andGasonSlimmedSiPixels]
Calice(W/Si);dualReadOut‐ElmCaloFwdHadrCalo:Cu/Brass‐ScinKllator
BwdDetectors(downto179o)SiliconTracker[Pix/Strip/Strixel/PadSiliconor/andGasonSlimmedSiPixels]
Cu/Brass‐ScinKllator,Pb‐ScinKllator(SpaCal‐hadr,elm)
ExtensionsinfwddirecKon(tagp,n,d)andbackwards(e,γ)understudy.
Comple8onoftheCDR AcceleratorDesign[RRandLR]
OliverBruening(CERN),
JohnDainton(CI/Liverpool)
Interac8onRegionandFwd/Bwd
BernhardHolzer(DESY),
UweSchneeekloth(DESY),
PierrevanMechelen(Antwerpen)
DetectorDesign
PeterKostka(DESY),
RainerWallny(UCLA),
AlessandroPolini(Bologna)
NewPhysicsatLargeScales
GeorgeAzuelos(Montreal)
EmmanuellePerez(CERN),
GeorgWeiglein(Hamburg)
PrecisionQCDandElectroweak
OlafBehnke(DESY),
PaoloGambino(Torino),
ThomasGehrmann(Zuerich)
ClaireGwenlan(Oxford)
PhysicsatHighPartonDensi8es
NestorArmesto(SanKago),
BrianCole(Columbia),
PaulNewman(Birmingham),
AnnaStasto(PennState)
OliverBruening(CERN)JohnDainton(Cockcrop)AlbertDeRoeck(CERN)StefanoForte(Milano)MaxKlein‐chair(Liverpool)PaulNewman(Birmingham)EmmanuellePerez(CERN)WesleySmith(Wisconsin)BerndSurrow(MIT)KatsuoTokushuku(KEK)UrsWiedemann(CERN))
GuidoAltarelli(Rome)SergioBertolucci(CERN)StanBrodsky(SLAC)AllenCaldwell‐chair(MPIMunich)SwapanChaiopadhyay(Cockcrop)JohnDainton(Liverpool)JohnEllis(CERN)JosEngelen(CERN)JoelFeltesse(Saclay)LevLipatov(St.Petersburg)RolandGaroby(CERN)RolandHorisberger(PSI)Young‐KeeKim(Fermilab)AharonLevy(TelAviv)KarlheinzMeier(Heidelberg)RichardMilner(Bates)JoachimMnich(DESY)StevenMyers,(CERN)TatsuyaNakada(Lausanne,ECFA)GuenterRosner(Glasgow,NuPECC)AlexanderSkrinsky(Novosibirsk)AnthonyThomas(Jlab)StevenVigdor(BNL)FrankWilczek(MIT)FerdinandWilleke(BNL)
Scien8ficAdvisoryCommiPee
SteeringCommiPee
WorkingGroupConvenors
1. Finalisephysicsandtechnicalstudies2. DIS10Firenze[April]andIPACCJapan[May]3. DrapCDRJune20104. DivonneIII–UpdatesandDiscussionwithreferees5. November10:FinalreporttoECFA6. SubmitCDRtoCERN,ECFA,NuPECC
LHeCreliesonexper8seandenthusiasmofmanycolleaguesandsupportbyECFA,NuPECCandCERN
Stepstogoin2010
LHeCbarack561
Backupslides
Quark‐GluonDynamics‐Diffrac8onandHFS(fwdjets)
Diffrac8ontoaccompany(SUSY)HiggsfwdphysicsatLHC
Understandmul8‐jetemission(unintegr.pdf’s),tuneMC’sAtHERAresolvedγeffectsmimicnon‐ktorderedemissionCrucialmeasurementsforQCD,andforQCDattheLHC
HERA
P.Newman,DIS07
H.Jung,L.Loennblad,THERAstudy
E. Perez LHeC Workshop, Sep 09
Determina8onofLQproper8esinsingleproduc8on:e.g.FermionNumber
Inpp:lookatsignalseparatelywhenresonanceisformedby(e++jet)and(e‐+jet):
SignoftheasymmetrygivesF,butcouldbestaKsKcallylimitedatLHC.(*)
Easierinep!Justlookatthesignalwithincidente+andincidente‐,buildtheasymmetrybetweenσ(e+in)andσ(e
‐in).
σ(e+out)>σ(e‐out)
forF=0
e+
q
g
q e‐
F=0
• λ
e‐
q
g
q e‐
__
F=0
• λ
IfLHCobservesaLQ‐likeresonance,M<1‐1.5TeV,LHeCcoulddetermineFifλnottoosmall.
(*)Firstroughstudydoneforthe2006paper.Needtocheck/refinewithafullanalysisofsignalandbackgrounds.
Quark‐GluonDynamics(satura8on,GPDs)‐ep
LHeCopensphasespacetodiscoversatura8oninDIS
Highluminosity,polarisa8on,accuracyforGPD’s(DVCS)
P.Newman,L.Favart,DIS08
J.BartelsatDivonneonlowxtheoryJ.Forshawetal,DIS08
Divonne08
StrongCouplingConstantαsleastknownofcouplingconstantsGrandUnificaKonpredicKonssufferfromδαs
DIStendstobelowerthanworldaverage
LHeC:permilleaccuracyindep.ofBCDMS.Challengetoexperimentandtoh.o.QCD
SimulaKonofαsmeasurementatLHeC
1/α
MSSM‐B.Allnachetal,hep‐ex/0403133
finestructure
weak
strong
NewPhysicsintheeqSector
?LQ,RPVSUSYSpectroscopy
?Excitedfermions
28Exactknowledgeofpdf’smaybecrucialtounderstandCI’s