electron-ion colliders · 2011-08-04 · int workshop – examples of ... performance parameters...
TRANSCRIPT
Electron-Ion Colliders
Sam Aronson IUPAP WG 9 Meeting
Cambridge, MA July 24, 2011
Focus on initiatives in the US Nuclear Physics community Topics
• EIC Science • BNL and JLab plans • Process for developing EIC plans into a DOE-based initiative
EIC High √s (~100GeV), high L (~1034/cm2sec) machine, staged approach; driven by US “QCD” community
Beyond form factors and quark distributions – Generalized Parton and Transverse Momentum Distributions
Proton form factors, transverse charge & current densities
Structure functions, quark longitudinal momentum & helicity distributions
X. Ji, D. Mueller, A. Radyushkin (1994-1997)
Correlated quark momentum and helicity distributions in transverse space - GPDs
Extend longitudinal quark momentum & helicity distributions to transverse momentum distributions - TMDs 2000’s
CompellingColdQCDMa0erDiscoveriesatRHIC
Stronghintsofgluondensitysatura2onfromsuppres‐sionofforward‐forwarddi‐hadronsincentrald+Au
Indica2onsofsmallposi2vecontribu2ontoprotonspinfrom0.05<xg<0.2gluons,viahelicitycorrela2ons
B h+v pickups Y h+v kickers
B h+v kickers Y h+v pickups
5-9 GHz, cooling times ~1 h
Horiz. Kicker (open)
RHICLuminosityUpgradesUnderWay RHIC breakthrough in bunched-
beam stochastic cooling overcomes intrabeam scattering limits, facilitates ~x10 improvement in heavy-ion collision rates, 4 years earlier and at ~1/7 the cost envis-ioned in 2007 NP Long Range Plan.
Much of the new system commissioned during 2010, rest anticipated for 2012-2014 runs (aided by ARRA funds).
Electron lenses (with ARRA + AIP support) to be installed for 2013 run will use few keV e+p collisions to compensate partially for p+p beam-beam betatron tune shift/spread
Hope to improve polarized p+p luminosities by factor ~2
What Will EIC Have That HERA Didn’t?
1) Heavy-ion beams to take advantage of coherent contributions of many nucleons to gluon density, provide more cost-effective reach into gluon saturation regime when QCD coupling is still weak
3) Polarized proton and 3He (for neutron), as well as electron, beams to pursue search for gluon contributions to nucleon spin down to very soft gluons, and map spin-momentum correlations of quarks and gluons inside nucleons
INT Workshop – examples of output
Articulating the compelling EIC measurements; matrices are shorthand summaries of INT work • Spin with polarized e, p • Gluon saturation with e, A
Vis-à-vis earlier MeRHIC design, this allows for:
more IP’s
reduced cost
reusing infrastructure + det. components for STAR, PHENIX
easier upgrade path from 5 GeV eRHIC-I
minimal environmental impact concerns
IR design to reach 1034 luminosity
RHIC: >275 GeV p or >110 GeV/u Au with
DX magnets removed
BNL’sEICConcept:eRHIC⇒High‐Resolu@on,Ultra‐FastImagingofGluon‐DominatedMaGer
JLab Concept: MEIC Layout
Prebooster Ion source
Three Figure-8 rings stacked
vertically
Ion transfer beam line
Medium energy IP with horizontal crab crossing
Electron ring
Injector
12 GeV CEBAF
SRF linac
Warm large booster (up to 20 GeV/c)
Cold 97 GeV/c proton collider
ring
medium energy IP
low energy IP
Three compact rings: • 3 to 11 GeV electron • Up to 20 GeV/c proton (warm) • Up to 100 GeV/c proton (cold)
https://eic.jlab.org/wiki/index.php/Machine_designs
ColliderPerformanceParametersforRHICvs.JLabDesignsHaveConvergedinPastYear
e+pfacilities
e+Afacilities
Activity/Project (Blue=Accel. + Det. R&D; Red=EIC Science Case) Total Cost FY10 FY11 FY12 est. FY13 est.
EIC Polarized Electron “Gatling” Gun $810K $128K $382K $300K
Laser System for Polarized Electron Source Photocathode
$430K $225K $205K
FEL-Based Coherent Electron Cooling $414K $95K $319K
Study of FEL Options for eRHIC $384K $205K $179K
Upgrade of IP2 Cryosystem for Coherent Electron Cooling Test
$2152K (Prog. Dev.)
$648K $817K $687K
CMOS Pixel Vertex Detector for EIC $607K $199K $202K $206K
Getting to Know Your Constituents: Studies of Partonic Matter at EIC
$413K $167K
Realization of e+A Physics Event Generator for the EIC
$384K $158K $137K $89K
Signatures of Saturation and Universality in e+A Collisions at eRHIC
$423K $79K $191K $153K
Electroweak Physics with an Electron-Ion Collider
$369K $203K $166K
Exploring the Role of Glue in Hadron Structure by an EIC
$597K $191K $202K $204K
Total approved to date = $6983K $1055K $2643K $1942K $1097K
New Proposal: Quantum Electrodynamics for QCD Precision Studies at the EIC
$282K $146K $136K
StrongBNLLDRD+PDSupportforeRHICPrograms
April 10, 2011: 3rd EIC International Advisory Committee meeting
May 9-10, 2011: Detector Advisory Committee review of first round of submitted EIC detector R&D proposals
Aug. 1-3, 2011: eRHIC technical design review
Fall 2011: EIC science White Paper (Steering Committee appointed and charged, with BNL-JLab-EICC agreement)
eRHIC cost review
Fall 2012 (??): Town Meetings for next Nuclear Physics LRP?
UpcomingandRecentPlanningExercisesandMilestones
• 2010INTWorkshop“yellowbook”–anGcipated~500pages,availableSpring2011–shouldserveasstarGngpoint,but…
• WhitePapershouldbe~100pages,aimedatnon‐experts,usefulfor“champions”withinDOE,suitableforrestofNPcommunity
• Needs~5‐pagegeneralintro(“elevatorspeech”amplified)tolayoutgoals,importanceanduniqueness,answerbasicquesGonsraisedatlastLongRangePlaninclear,concise,compellingfashion
• ~10‐pagesciencesecGonstofleshout“goldenexperimentmatrices”forseveralareas,withsimulated“moneyplots,”lightontechnicaldetail
• ~10‐15pagesonbasicmachineparameters,designopGons,challenges+~10pagesondetectordesignfeaturesandchallenges
• SteeringCommi0eecomprisingexperimentalist/theoristpairs,broadlyrepresentaGveofinterestedinsGtuGons
AimforEICScienceWhitePaperbyEndofCY2011
EIC Realization Imagined Activity Name 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
12 Gev Upgrade
FRIB
EIC Physics Case NSAC LRP
CD0
Machine Design/R&D
CD1/D’nselect
CD2/CD3
Construction
Poten@alElectron‐IonColliderTimelineShownbyHughMontgomeryatINTWorkshop,Sept.2010
N.B. It is unlikely ONP could support operations at 3 major facilities (RHIC, CEBAF, FRIB) and simultaneous construction of a 4th (EIC) after ~2018.
Discussion/Ques@ons