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EIC Detector R&D Simulation Workshop Summary. Simulation Workshop. Workshop@BNL 8 th & 9 th of October https://wiki.bnl.gov/conferences/index.php/EIC_RD_Simulation/ Agenda Covered Topics Physics case for the EIC Golden measurements to benchmark the detector performance Software
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EIC Detector R&D Simulation WorkshopSummary EIC Detector R&D Committee Meeting, October 2012
Simulation Workshop • Workshop@BNL 8th & 9th of October • https://wiki.bnl.gov/conferences/index.php/EIC_RD_Simulation/Agenda • Covered Topics • Physics case for the EIC • Golden measurements to benchmark the detector performance • Software • simulation tools (physics generators,fast smearing generator,..) • physics generators not discussed here summarized perfectly in https://wiki.bnl.gov/conferences/images/d/db/TollEICRnDOctober2012.pdf • detector simulations (FairRoot@BNL, GEMC@JLab, ….) • computing power and environment • eRHIC and ELIC/MEIC IR designs • tracking of protons and neutrons through IR • machine backgrounds (hadronic, synchrotron radiation, …) EIC Detector R&D Committee Meeting, October 2012
~ H, H, E, E (x,ξ,t) g, p,J/Y e gL* (Q2) x+ξ x-ξ ~ t What needs to be covered e’ • Inclusive Reactions in ep/eA: • Physics: Structure Fcts.: F2, FL • Very good electron id find scattered lepton • Momentum/energy and angular resolution of e’ critical • scattered lepton kinematics p’ p • Semi-inclusive Reactions in ep/eA: • Physics: TMDs, Helicity PDFs flavor separation, dihadron-corr.,… • Kaon asymmetries, cross sections • Excellent particle ID: p±,K±,p± separation over a wide range in h • full F-coverage around g* • Excellent vertex resolution Charm, Bottom identification • Exclusive Reactions in ep/eA: • Physics: GPDs, proton/nucleus imaging, DVCS, excl. VM/PS prod. • Exclusivity large rapidity coverage rapidity gap events • ↘ reconstruction of all particles in event • high resolution in t Roman pots EIC Detector R&D Committee Meeting, October 2012
Inclusive DIS Measure of resolution power Measure of inelasticity Note: • to measure x, y, and Q2 at low Q2 ~ 1 GeV2 • Electron method • precise energy and angular resolution for q’e 180o and high y • At low y use hadron method Measure of momentum fraction of struck quark p/A e- 0o 180o +h -h Hadron method: diverges for ye0 depends on E’e diverges for q’e180o depends on E’eand q’e EIC Detector R&D Committee Meeting, October 2012
DIS Kinematics Possible limitations in kinematic coverage: high y limited by radiative corrections can be suppressed by requiring hadronic activity HERA y>0.005 low y-coverage: limited by E’e resolution hadron method • Even for colliders: Strong x-Q2 correlation • high x high Q2 • low x low Q2 EIC Detector R&D Committee Meeting, October 2012
Lepton Kinematics Increasing Lepton Beam Energy: 5 GeV: Q2 ~ 1 GeV h ~ -2 10 GeV: Q2 ~ 1 GeV h ~ -4 highest E’e at most negative rapidities independent of Eh √s EIC Detector R&D Committee Meeting, October 2012
Scattered Lepton Kinematics CUTS: Q2>0.1GeV2 && 0.01<y<0.95 higher √s: scattered lepton has small scattering angle negative rapidities EIC Detector R&D Committee Meeting, October 2012
Pion Kinematics Cuts: Q2>1 GeV, 0.01<y<0.95, z>0.1 √s • Increasing Hadron Beam Energy: influences max. hadron energy at fixed h • Increasing 30 GeV < √s < 170 GeV • hadrons are boosted from forward rapidities to negative rapidities • the same for p±, K±, p± EIC Detector R&D Committee Meeting, October 2012
Hadron, lepton, Photon Separation 5 GeVx50 GeV hadron photon electron no cuts applied pmaxhadron for PID: -5<h<-1: < 10 GeV -1<h<-1: < 5 GeV 1<h<5: < 50 GeV hadron/photon suppression factor needed for pe’>1GeV: -3<h<-2: ~10 -2<h<-1: > 100 -1<h<0: ~1000 EIC Detector R&D Committee Meeting, October 2012
Lepton Identification 20 GeVx250 GeV hadron photon electron no cuts applied pmaxhadron for PID: -5<h<-1: < 30 GeV -1<h<-1: < 10 GeV 1<h<5: < 100 GeV hadron/photon suppression factor needed for pe’>1GeV: -4<h<-3: >100 -3<h<-2: ~1000 -2<h<-1: > 104 EIC Detector R&D Committee Meeting, October 2012
Fast Simulator: What was modeled • Magnetic field: Solenoid with 3.0Tesla • Tracking: • “Central” +/-1: TPC-like: • 45 fit points; 0.03 radiation length, position resolution: 80 m • “Forward” 1-3: GEM-like: • 6 planes; 0.03 radiation length, position resolution: 80 m • “Far Forward” 3-4.5: Si-Pixel-like: • 12 planes; 0.03 radiation length, position resolution: 20 m • radiation length needs to be checked • no bremsstrahlung for electrons yet • Ecal • “Central” +/-1: like submitted proposal • 10%√E+1.5% hadron: MIP + 0.4Eh with s=0.2Eh (50:50) • “Forward” 1-5: like submitted proposal • 10%√E+1.5% hadron: MIP + 0.4with s=0.2Eh (50:50) • “Backward” -1 to -5: PWO crystal calorimeter • 2.5%/√E+ 0.9% + 1%/E hadron: MIP + 0.4Eh with s=0.2Eh (50:50) • “Hcal: • Forward” 1-5: like current STAR forward R&D project: • 38%√E+3% EIC Detector R&D Committee Meeting, October 2012
Fast Simulator: Check -1< h <1 assumed 0.05 radiation lengths • Used fast smearing simulator • multiple scattering and momentum smearing included according to PDG • check against STAR results at central region looks okay • for details: https://wiki.bnl.gov/conferences/images/d/d1/R%26DOctoberSmearing.pdf EIC Detector R&D Committee Meeting, October 2012
Momentum resolutions 0.5<h<1.5 1.5<h<2.5 To improve momentum resolution for h>3 need to look in Magnet design with more radial field 3.5<h<4.5 2.5<h<3.5 EIC Detector R&D Committee Meeting, October 2012
compare performance of tracking to F_L requirements as determined by Chiapas want plot to compare Calo. resolutions with tracking for different rapidity EIC Detector R&D Committee Meeting, October 2012
Improve Momentum Resolution: Magnet Design Discuss on one slide our results for the ILC-concept 4 magnet vs. normal Solenoid EIC Detector R&D Committee Meeting, October 2012
Resolution for E/p Ee: 5 GeV Q2>1 GeV-1<h<-1 Ee: 20 GeV Q2>1 GeV-1<h<-1 1<p<3 1<p<2 4<p<5 7<p<9 EIC Detector R&D Committee Meeting, October 2012
Resolution for E/p Ee: 5 GeV Q2>1 GeV -2.2<h<-1 Ee: 20 GeV Q2>1 GeV-3.7<h<-1 1<p<3 1<p<2 4<p<5 7<p<9 EIC Detector R&D Committee Meeting, October 2012
LHC-b: possible RICH design concepts RICH-1 (modern HERMES RICH) RICH-2 2<p<60 GeV 17<p<100 GeV 25-300 mrad 10-120 mrad 5cm Aerogel (n=1.030) ~200 cm CF4 (n=1.0005) 85 cm C4F10 (n=1.0014) EIC Detector R&D Committee Meeting, October 2012
Cerenkov and momentum resolution dp/p< 1.0% dp/p< 3.0% dp/p<0.1% p K p • no resolution due to photon detector is yet modeled • momentum resolution absolutely critical for good p, K, p separation EIC Detector R&D Committee Meeting, October 2012
Diffractive peak Q2 W MY Exclusive Reactions: Event Selection How can we select events: two methods • proton tag method • Measurement of t • Free of p-diss background • Higher MX range • to have high acceptance (roman • Pots) challenging IR design Need for roman pots spectrometer • Large Rapidiy Gap method • X system and e’ measured • Proton dissociation background • High acceptance Need for Hcal in the forward region EIC Detector R&D Committee Meeting, October 2012
Scattered proton acceptance Main detector leading protons are never in the main detector acceptance at EIC (stage 1 and 2) eRHICdetector acceptance Roman Pots Cuts: Q2>1 GeV, 0.01<y<0.95, Eg>1 GeV • Increasing Hadron Beam Energy: • influences max. photonenergy at fixed h • Increasing 30 GeV < √s < 170 GeV • photons are boosted from symmetric • to negative rapidities EIC Detector R&D Committee Meeting, October 2012
t-Measurement using RP Accepted in“Roman Pot”(example) at s=20m Plots from J-H Lee 20x250 GeV Quadrupoles acceptance 5x100 GeV 5x100 GeV Simulation based on eRHIC 10sfrom the beam-pipe • REQUIREMENTS • Acceptance at large-|t| proper design of quadrupole magnets • Acceptance in the whole solid angle • High momentum resolution • radiation hardness • • high‐|t| acceptance mainly limited by magnet aperture • • low‐|t| acceptance limited by beam envelop (~10σ) • • |t|‐resolution limited by • – beam angular divergence ~100μrad for small |t| • – uncertainties in vertex (x,y,z) and transport • – ~<5-10% resolution in t (RP at STAR) EIC Detector R&D Committee Meeting, October 2012
g Photon-Lepton discrimination Dq e N.B. - Need for a ECalwith a granularity to distinguish clusters down to Dq=1 deg This is also important for Df calculation in asymmetries measurement an for BH rejection in the xsec measurement EIC Detector R&D Committee Meeting, October 2012
BH rejection BH and DVCS BH dominated In DVCS most of the photon are less “rear” Than the electrons: (θel-θg) > 0 rejects most of the BH EIC Detector R&D Committee Meeting, October 2012
BH Rejection Eel Eγ Eel Eγ Eel Eγ Eel Eγ BH electron has very low energy (often below 1 GeV) Photon for BH (ISR) goes often forward (trough the beam pipe) Important: ECalmust discriminate clusters above noise down to 1 GeV EIC Detector R&D Committee Meeting, October 2012
Start full Geant Simulations • Postdoc Alexander Kiselev started 3rd of Dec. 2012 • Framework: virtual MC using FairRoot EIC Detector R&D Committee Meeting, October 2012
Some thought about rates low multiplicity 4-6 √s = 40-65 GeV Nch (ep) ~ Nch (eA) < Nch(pA) no occupancy problem Cross section: Pythiasep: 0.030 – 0.060 mb Luminosity: 1034 cm-1 s-1 = 107 mb-1 s-1 Interaction rate: 300 -600 kHz EIC Detector R&D Committee Meeting, October 2012
Summary EIC Detector R&D Committee Meeting, October 2012
BACKUP EIC Detector R&D Committee Meeting, October 2012
Executive Summary ----------------------------- Physicists representing several of the current EIC R&D efforts met for two days at Brookhaven Lab. The purpose of the meeting was to consolidate simulation efforts to most efficiently formulate: 1) Physics-driven detector performance constraints. 2) Radiation dose estimates (including machine-specific backgrounds). 3) Coherent simulation strategies. Presentations included discussion on: * The physics scope of EIC. * Processes that drive detector performance. * Current software efforts. * Available computing resources. * Detailed machine designs. * Current machine-background estimates. In the concluding session, the participants formulated both their broad goals and a short-term To-Do list. BROAD GOALS: 1) Formulate Requirement Tables/Maps. Each requirement table/map stipulates the limiting values of a detector performance parameter (e.g. dp/p, material budget, PID purity) as functions of both polar angle and particle momentum. These tables/maps in principle can be made for each driving physics process. 2) Formulate a Dose Table/Map. Dose Tables/maps specify the radiation load on detector systems from various sources (collisions, backgrounds) as functions of detector location. 3) Build a Full Simulation. The full simulation should follow modern coding practices as a "virtual simulation framework" (e.g. FairRoot or GEMC) and incorporate both physics and background sources. EIC Detector R&D Committee Meeting, October 2012
4) Formulate Systematic Error Estimates. EIC will be systematics-limited, not statistics-limited. Experimental sources of systematic error (calibration, scale determination, final state radiation, machine background) should be evaluated relative to attainable theoretical uncertainties. Clearly this task requires the detailed full detector simulation for measurements of inclusive, exclusive, and SIDIS channels. SHORT TERM TO DO LIST: 1) Constraint Maps: Develop requirement maps for SIDIS & DVCS to complement those for inclusive cross sections. 2) Dose Maps: Starting with the physics dose map, add backgrounds from the electron beam (bremsstrahlung) and hadron beam (beam-gas). 3) Simulation Development: a- Implement a double-solenoid field map. b- Stipulate by Email and Phone Conference the radial budgets for detector subsystems. c- Assign initial coding options to people with appropriate interests. EIC Detector R&D Committee Meeting, October 2012
lepton kinematics EIC Detector R&D Committee Meeting, October 2012
Simulation Example Cuts: Q2>1 GeV, 0.01<y<0.95, z>0.1 EIC Detector R&D Committee Meeting, October 2012
Integration into Machine: IR-Design • Outgoing electron direction currently under detailed design • detect low Q2 scattered leptons • want to use the vertical bend to separate very low-Qe’ from beam-electrons • can make bend faster for outgoing beam faster separation • for 0.1o<Q<1o will add calorimetry after the main detector space for low-Qe-tagger EIC Detector R&D Committee Meeting, October 2012
Emerging Detector Concept Magnet 2-3T BackwardSpectrometer For very low Q2-electrons: space for low-Q e-tagger • high acceptance -5 < h < 5 central detector • good PID (p,K,p and lepton) and vertex resolution (< 5mm) • tracking and calorimeter coverage the same good momentum resolution, lepton PID • Barrel: MAPS & TPC, Forward: MAPS & GEM • low material density minimal multiple scattering and brems-strahlung • very forward electron and proton/neutron detection Roman Pots, ZDC, low e-tagger EIC Detector R&D Committee Meeting, October 2012
Kinematics of Breakup Neutrons Results from GEMINI++ for 50 GeV Au • Results: • With an aperture of ±3 mrad we are in relative good shape • • enough “detection” power for t > 0.025 GeV2 • • below t ~ 0.02 GeV2 we have to look into photon detection • ‣ Is it needed? • Question: • For some physics rejection power for incoherent is needed ~104 • How efficient can the ZDCs be made? by Thomas Ullrich +/-5mrad acceptance seems sufficient EIC Detector R&D Committee Meeting, October 2012
Diffractive Physics: p’ kinematics t=(p4-p2)2 = 2[(mpin.mpout)-(EinEout - pzinpzout)] “ Roman Pots” acceptance studies see later Diffraction: 5x50 ? p’ 5x100 5x250 Simulations by J.H Lee EIC Detector R&D Committee Meeting, October 2012
proton distribution in yvsx at s=20 m without quadrupole aperture limit 20x250 5x50 with quadrupole aperture limit 5x50 20x250 EIC Detector R&D Committee Meeting, October 2012
Accepted in“RomanPot”(example) at s=20m 20x250 5x50 Summary: • Still a lot of work to be done • But we have started to address all the important issues • integration of detector and forward particle reconstruction into machine design • Synchrotron radiation ……… 20x250 5x50 Generated Quad aperture limited RP (at 20m) accepted EIC Detector R&D Committee Meeting, October 2012
Dipole Cross-Section: J/ψ ϕ Exclusive Vector Meson Production • Golden channel: e + A → e’ + A’ + VM • Only channel where t can be derived from VM and e’ • Detecting neutron emission from nuclear breakup allows to separate coherent from incoherent EIC Detector R&D Committee Meeting, October 2012
Detection efficiency of Breakup Neutrons Results: With an aperture of ±3 mrad we are in relative good shape even for 50 GeV Au beams • enough “detection” power for t > 0.025 GeV2 • below t ~ 0.02 GeV2 we have to look into photon detection ‣ Is it needed? Assumptions: • Gemini++ is correct, was verified by SMM • E* ~ -t/2mN • Can we make a ZDC 100% (>99.9999%) efficient ‣ do we understand neutron detection on the 10-4 level? EIC Detector R&D Committee Meeting, October 2012