Talk - EIC/LHC Synergy Workshop, Krakow 2025

Physics Performance of the Detector Ongoing and Planned Studies EIC Detector-1BNL-INT Joint Workshop: Bridging Theory and Experiment at the Electron-Ion Collider Joint ECFA-NuPECC-APPEC Workshop on “Synergies between the EIC and the LHC” Krakow - September 22-24, 2025 Salvatore Fazio Università della Calabria & INFN Cosenza 2 EIC science pillars The EIC will unravel the different contribution from the quarks, gluons and orbital angular momentum SPIN is one of the fundamental properties of matter. All elementary particles, but the Higgs carry spin. Spin cannot be explained by a static picture of the proton It is the interplay between the intrinsic properties and interactions of quarks and gluons How can we understand their dynamical origin in QCD? What is the relation to Confinement How are the quarks and gluon distributed in space and momentum inside the nucleon & nuclei? How do the nucleon properties emerge from them and their interactions? Does the mass of visible matter emerge from quark-gluon interactions? Atom: Binding/Mass = 0.00000001 Nucleus: Binding/Mass = 0.01 Proton: Binding/Mass = 100 For the proton the EIC will determine an important term contributing to the proton mass, the socalled “QCD trace anomaly How do the confined hadronic states emerge from quarks and gluons? Is the structure of a free and bound nucleon the same? How do quarks and gluons, interact with a nuclear medium? How do the quarkgluon interactions create nuclear binding? What happens to the gluon density in nuclei? Does it saturate at high energy? How many gluons can fit in a proton? How does a dense nuclear environment affect the quarks and gluons, their correlations, and their interactions? QS: Matter of Definition and Frame (II) 7 Infinite Momentum Frame: •BFKL (linear QCD): splitting functions 󲰛 gluon density grows •BK (non-linear): recombination of gluons 󲰛 gluon density tamed BFKL: BK adds: αs << 1αs ∼ 1 ΛQCD know how to do physics here ? max. density QskT ~ 1/kT kT φ(x, kT 2) •At Qs: gluon emission balanced by recombination Unintegrated gluon distribution depends on kT and x: the majority of gluons have transverse momentum kT ~ QS (common definition) QS: Matter of Definition and Frame (II) 7 Infinite Momentum Frame: •BFKL (linear QCD): splitting functions 󲰛 gluon density grows •BK (non-linear): recombination of gluons 󲰛 gluon density tamed BFKL: BK adds: αs << 1αs ∼ 1 ΛQCD know how to do physics here ? max. density QskT ~ 1/kT kT φ(x, kT 2) •At Qs: gluon emission balanced by recombination Unintegrated gluon distribution depends on kT and x: the majority of gluons have transverse momentum kT ~ QS (common definition) ? = gluon splitting gluon recombination 5/21/2025 Rolf Ent’s talk 3 What process must be measured? Neutral Current DIS ●Detection of scattered electron with high precision - event kinematics Charged Current DIS ●Event kinematics from the final state particles (JacquetBlondel method) Semi-Inclusive DIS ●Precise detection of scattered electron in coincidence with at least 1 hadron Exclusive Processes ●Detection of all particles in event DIS event kinematics - scattered electron or final state particles (CC DIS, low y) Parton Distributions in nucleons and nuclei Spin and Flavor structure of nucleons and nuclei QCD at Extreme Parton Densities - Saturation Tomography Spatial Imaging Tomography Transverse Momentum Dist. QCD at Extreme Parton Densities - Saturation ∫ℒdt: ~1%fb!" ~10%fb!" ~100%fb!" 4 §PWGs at ePIC typically meet by-weekly §Global Physics Analysis Coordination by-weekly Structure of the Physics Working Groups SINCLUSIVE PHYSICS Win Lin (Stony Brook) Stephen Maple (Birmingham) SSEMI-INCLUSIVE PHYSICS Anselm Vossen (Duke) Ralf Seidl (RIKEN) SEXCLUSIVE, DIFFRACTION AND TAGGING Stephen Kay (York) Zhoudunming Tu (BNL) SJETS AND HEAVY FLAVOR Shyam Kumar (Bari) Rongrong Ma (BNL) SBSM AND PRECISION EW Zuhal Seyma Demiroglu (Stony Brook) Juliette Memmei (Manitoba) PHYSICS ANALYSIS COORDINATORS Salvatore Fazio (Calabria) - Rachel Montgomery (Glasgow) Rosi Reed (Lehigh) - deputy Ingredients we need: oA flexible collider (EIC) oA versatile general-purpose detector (ePIC) oAn engaged and enthusiastic International Collaboration Rolf Ent’s talk BrianPage’s talk 528 June 2024 pre–TDR (60% design completion) ⟹ December 2025 TDR (90% design completion) ⟹ ~ late 2026 §(pre)TDR are a deliverable of the EIC/ePIC Project Technical Design Report Rolf Ent’s talk 6 EIC Early Science Report oCharge by BNL/JLAB Associate Lab Directors [by May 1st] oDedicated “physics readiness” workshops: •Sep. 13, 2024 – online [link] •Jan. 2025, plenary at Coll. Meeting [link] •Apr. 2025, CFNS @ Stony Brook [link] •Sep. 2025, IoP in London [link] •Next Feb/March 2026 oGoal of this exercise: •Highlight meaningful and impactful science within early years of running without undermining the importance of achieving full EIC capabilities •Meaningful: The EIC early science program must engage the collaboration; it must get the collaboration excited about working hard for the future. It must have a balance of breadth and depth •Impactful: The EIC early science program must take the first steps down the path to realizing the EIC science goals 7 Highlights on the performance on some physics measurements of the detector §ALL IS A WORK IN PROGRESS! •Software framework, event reconstruction, tools... are being finalized and are evolving as we speak! oGluons have no mass and quarks are very light, but nucleons and nuclei are heavy, making up for most of the visible mass in the Universe oVisible matter only made of constituents of light mass: masses emerge from quark-gluon dynamics Proton (valence quarks: uud) →𝑚!=940 MeV •The mass is dominated by the energy of highly relativistic gluonic field •EIC can determine an important contribution term to the proton mass, the so-called “QCD trace anomaly” ⟼ accessible in exclusive reactions (e.g. Y photoproduction near threshold) Scientific goals: origin of the mass of visible matter 8 Key detector performance: •Acceptance and low material for VM decay leptons •Resolution of lepton pair inv. mass •Muon id 9 ePIC performance: 𝚼 production •Ratio yields 1 : 0.45 : 0.33 from STARlight paper •Fitted with the Double-Sided Crystal Ball function •𝑚!"# = 𝑚!$# PDGmass!" PDGmass#" ϒ(1S), ϒ(2S), ϒ(3S) → 𝑒!𝑒" oSensitivity to gluon distributions oChallenges: tracking resolution is crucial oFirst studies at low 𝑄% left -> right: Different rapidity intervals 16 Scientific goals: GPDs Spin-½ hadron: 4 chiral-even (𝐻, 𝐸 and their polarizedhadron versions / 𝐻, 0 𝐸) and 4 chiral-odd (𝐻', 𝐸',/ 𝐻', 0 𝐸') quark and gluon GPDs at leading twist Like usual PDFs, GPDs are non-perturbative functions defined via the matrix elements of parton operators: ℋ 𝜉,𝑡 =0 $ 𝑒$ %2 &' '𝑑𝑥5𝐻$𝑥,𝜉,𝑡 1 𝜉−𝑥−𝑖𝜀−1 𝜉+𝑥−𝑖𝜀 •Experimental access to GPDs via Compton Form Factors (CFFs) Longitudinal momentum & helicity distributions 𝒇 𝒙 % parton densities transverse charge & current densities 𝑭 𝒕 form factors 𝑯 𝒙, 𝝃, 𝒕 % GPDs •Measure t-differential cross sections and asymmetries in exclusive processes Mandelstam variable: 𝒕=− 𝒑(−𝒑 𝟐 17 ePIC performance: proton momentum via f.f. spectrometers 𝒕 = − 𝒑=− 𝒑 𝟐, in exclusive and diffractive processes is directedly measured via far forward trackers, roman pots (RPs) and B0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 ] 2 )c|t| [(GeV/ 1 10 2 10 3 10 4 10 5 10 2 )cCounts / 0.02 (GeV/ SimulationePIC ep 10x100 GeV 2 < 1 GeV 2 miss , M 2 0.3 GeV≤ RP , t 2 1 GeV≥ 2 Q γ e'p'→ ep EpIC MC generatedEpIC < 20 mrad) p' θReconstructed (p' in B0 - 5.5 < < 5.5 mrad) p' θReconstructed (p' in RP - Reconstructed 𝒕 not corrected for acceptance Optimization studies ongoing! AlexJentsch’s talk Absolute 𝒕 resolution 18 TMDs surviving integration over 𝑘> Time-reversal odd TMDs describing strength of spin-orbit correlations Chiral odd TMDs Note: off-diagonal part vanishes without parton’s transverse motion Non-zero strength of spin-orbit correlations → indication of parton OAM oSivers: correlations of transverse-spin direction and the parton transverse momentum oBoer-Mulders: correlations of parton transverse spin and parton transverse momentum oCollins: fragmentation of a transversely polarized parton into a final-state hadron Scientific goals: TMDs 19 What we want to measure: Ø6-fold differential cross sections in SIDIS ØAzimuthal asymmetries and their modulations EIC envisions a rich program to probe spin-orbit effects within the proton and during hadronization, and explore the 3D spin structure of the proton in momentum space •Extends the SiDIS kinematic coverage of an order ~2 in both 𝑥 and 𝑄% EIC Yellow Report: kin. reach for Sivers and Collins EIC will access TMDs primarily through SIDIS for single hadrons, as well as other semi-inclusive processes with the production of di-hadrons and jets Scientific goals: TMDs Key detector performance: •Azimuthal acceptance •PID •Acceptance •Vertexing (heavy flavor) •Quality of tracking •HCal (for jets) 20 ePIC performance: Unpolarized TMDs °0.3 °0.2 °0.1 0.0 0.1 0.2 0.3down 0.00 0.25 0.50 0.75 1.00 |k?|[GeV] °0.6 °0.4 °0.2 0.0 0.2 0.4 0.6sea 0.00 0.25 0.50 0.75 1.00 |k?|[GeV] Q= 2 GeV, x=0.1Q= 2 GeV, x=0.001 Expected statistical/total uncertainty of un-polarized TMD PDFs for π+ •Inner (outer) circles: statistical(total) uncertainty •Colors: beam energy configuration with highest statistics in a bin Uncertainties based on the MAP24 global TMD fit •Lighter shades: based on existing data •Darker shades: after including ePIC data 21 ePIC performance: Collins Asymmetries §Collins asymmetries can be obtained from identified hadrons within jets §The Collins FF plotted vs the fractional hadron momentum z and transverse momentum relative to the jet momentum and its axis §Projections assume a 10 fb-1 luminosity 0.5 1 1.5 2 2.5 3 [GeV] T P 0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2 UT A 0.1000 < x < 0.2154 < 316 2 / GeV 2 100 < Q 0.5 1 1.5 2 2.5 3 [GeV] T P 0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2 UT A 0.0215 < x < 0.0464 < 32 2 / GeV 2 10 < Q ep 18 GeV x 275 GeV 0.5 1 1.5 2 2.5 3 [GeV] T P 0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2 UT A 0.0 < z < 0.2 + πReco A Col 0.2 < z < 0.6 + πReco A Col 0.6 < z < 1.0 + πReco A Col 0.0002 < x < 0.0005 < 3.2 2 / GeV 2 1.0 < Q 0.2 0.4 0.6 0.8 z 0.2− 0.1− 0 0.1 0.2 UT A 0.1000 < x < 0.2154 < 316 2 / GeV 2 100 < Q 0.2 0.4 0.6 0.8 z 0.2− 0.1− 0 0.1 0.2 UT A 0.0215 < x < 0.0464 < 32 2 / GeV 2 10 < Q ep 18 GeV x 275 GeV 0.2 0.4 0.6 0.8 z 0.2− 0.1− 0 0.1 0.2 UT A < 0.3 T 0.0 < P + πReco A Col < 1.2 T 0.3 < P + πReco A Col < 4.0 T 1.2 < P + πReco A Col 0.0002 < x < 0.0005 < 3.2 2 / GeV 2 1.0 < Q π+ π+ oCollins Asymmetry: effect due to convolution of quark transversity (ℎ' $) and Collins FF (𝐻'*/$ ,) •Advantage of jet+hadron Collins over single hadron SIDIS: •jets provide proxy for fragmenting parton 0.2 0.4 0.6 0.8 z 0.05− 0 0.05 ) H φ - S φsin( UT A πprojected stat. uncertainty projected stat. uncertainty K projected stat. uncertainty p ePIC Simulation -1 18 x 275 GeV, 100 fb jet + hadron + X→ ↑ e + p < 4.5 GeV/c T 0.05 < j < 51.9 GeV/c T 5.0 < Jet p 18x275 GeV – 100 fb-1 22 ePIC performance: Collins Asymmetries oProjected statistical precision for 𝜋, 𝐾, 𝑝 Collins Asymmetry oCollins Asymmetry: effect due to convolution of quark transversity (ℎ' $) and Collins FF (𝐻'*/$ ,) •Advantage of jet+hadron Collins over single hadron SIDIS: jets provide proxy for fragmenting parton 23 (Qs A)2~cQo 2A x ⎛ ⎝ ⎜⎞ ⎠ ⎟ 1/3 L ~ (2mN x)-1 > 2 RA ~ A1/3 Probe interacts coherently with all nucleons Gold: 197 times smaller effective x ! 1 10 10-3 103 10-2 102 10-1 110-4 x Q2 (GeV2) 0.1 EIC √s = 90 GeV, 0.01 ≤ y ≤ 0.95 EIC √s = 45 GeV, 0.01 ≤ y ≤ 0.95 Measurements with A ≥ 56 (Fe): eA/μA DIS (E-139, E-665, EMC, NMC) νA DIS (CCFR, CDHSW, CHORUS, NuTeV) DY (E772, E866) perturbative non-perturbative geometric scaling ln x non-perturbative region ln Q2 Q2 s(x) saturation JIMWLK BK DGLAP BFKL αs << 1 αs ~ 1 Qs 1 Au Ca p àEIC will map the transition between a non-saturated and a saturated regime with high precision, by making use of a large range of nuclei and spin àWith its flexible ion source, we will be able to measure the A-dependence of the saturation scale Qs(x) à a fundamental landmark of QCD QS: Matter of Definition and Frame (II) 7 Infinite Momentum Frame: •BFKL (linear QCD): splitting functions 󲰛 gluon density grows •BK (non-linear): recombination of gluons 󲰛 gluon density tamed BFKL: BK adds: αs << 1αs ∼ 1 ΛQCD know how to do physics here ? max. density QskT ~ 1/kT kT φ(x, kT 2) •At Qs: gluon emission balanced by recombination Unintegrated gluon distribution depends on kT and x: the majority of gluons have transverse momentum kT ~ QS (common definition) QS: Matter of Definition and Frame (II) 7 Infinite Momentum Frame: •BFKL (linear QCD): splitting functions 󲰛 gluon density grows •BK (non-linear): recombination of gluons 󲰛 gluon density tamed BFKL: BK adds: αs << 1αs ∼ 1 ΛQCD know how to do physics here ? max. density QskT ~ 1/kT kT φ(x, kT 2) •At Qs: gluon emission balanced by recombination Unintegrated gluon distribution depends on kT and x: the majority of gluons have transverse momentum kT ~ QS (common definition) gluon emission gluon recombination ?=? Scientific goals: gluon saturation 24 side-view: Low gluon density (ep): pQCD predicts 2→2 process ⇒ back-to-back di-jet e(k) ⎧ ⎨ ⎩ ⎧ ⎨ ⎩ electron proton/ nucleus eʹ(kʹ) p/A(p)x⋅p W q γ∗ θe q q A p jet-1 jet-2 beam-view: π Key detector performance: •Quality of detection at mid rapidity •Reconstruction of dijets (dihadron) •Particle ID Di-hadron correlations Scientific goals: gluon saturation Suppression: A-dependence Suppression: saturation effects High gluon density (eA): 2 → many process ⇒ expect broadening of away-side 25 ePIC performance: DVMP in e-A 𝑒Au → 𝜙 → 𝐾(𝐾) oCoherent electroproduction of 𝜙 meson in eA oSensitivity to gluon saturation oChallenges: PID and FF detectors crucial to measure the decay kaons, reconstruct 𝑡 and veto the incoherent part e(k) e'(k') A'(p') A(p) q gap Mx t Diffraction High sensitivity to gluon density in linear regime σ~[g(x,Q2)]2 detector at IP6 included in the EIC project 32 The Electron-Ion Collider World’s first Polarized electron-proton/light ion and electron-Nucleus collider üAdd a 5 to 18 GeV electron storage ring üTwo interaction regions, IP6 and IP8 üHigh Luminosity: 1033 -1034 cm-2s-1 (~102-103 * HERA) üFlexible √s = 29-141 GeV (per nucleon) üHighly polarized (~70%) 𝑒↑, 𝑝↑, 𝑑↑,𝐻𝑒↑, flexible spin pattern üWide variety of nuclear beams: (D to U) A DOE approved project! Could be the only new collider in the coming ~20-30 years 33 The detector •New 1.7 T solenoid •Si MAPS (vertex, barrel, forward, backward disks) •MPGDs (µRWELL/µMegas) (barrel, forward, backward disks) 5.3m •Imaging EMCAL (barrel) •W-powder/ScFi (forward) •PbWO4 crystals (backward) E.M. Calorimetry Hadronic Calorimetry Tracking Particle identification •High performance DIRC (barrel) •Dual radiator (aerogel+gas) RICH (forward) •Proximity focusing RICH (aerogel) (backward) •TOF (~30ps): AC-LGAD (barrel and forward) •Fe/Scint reuse from sPHENIX (barrel) •Steel/Scint - W/Scint (backwards/forward) DAQ: streaming/triggerless with AI 34 Far forward/backwards detectors p/A beam e beam Roman Pots and Off-Momentum Detectors Main Function: detection of forward scattered neutrons and g Technology: EMCAL: 2x2x20 cm3 PbWO4 calorimeter Synergy with backward ECal HCAL: Steel-SiPM-on-Tile Synergy with forward HCal Zero Degree Calorimeter Low-Q2 Taggers Main Function: detection of forward scattered protons and nuclei Technology: 2 stations with 2 tracking layers each AC-LGAD / EICROC ( 500x500 µm2 pixel) Synergy with forward ToF Main Function: detection of scattered electrons Technology: 2 stations with 4 tracking layers each (16x18cm2) Si / Timepix4 Calorimeter: Tungsten-powder + SciFi SPACAL Synergy with forward ECal Luminosity System Main Function: measure bunch-by-bunch luminosity through Bethe-Heitler process Technology: Pair-spectrometer: each with 2 tracking layers of AC-LGAD / FCFD Synergy with Barrel-ToF Calorimeter: Tungsten-powder + SciFi SPACAL Synergy with forward ECal B0 Magnet Sectrometer Main Function: detection of forward scattered protons and g Technology: 4 tracking layers each AC-LGAD / EICROC ( 500x500 µm2 pixel) Synergy with forward ToF EMCAL: 2x2x20 cm3 PbWO4 calorimeter Synergy with backward ECal 35 Tracking MAPS Barrel + Disks AC-LGAD based To F MPGD Barrels + Disks oMAPS Tracker: •Small pixels (20 μm), low power consumption (<20 mW/cm2) and low material budget (0.05% to 0.55% X/X0) per layer •Based on ALICE ITS3 development •Vertex layers optimized for beam pipe bake-out and ITS-3 sensor size •Forward and backward disks oMPGD Layers: •Provide timing and pattern recognition •Cylindrical μMEGAs •Planar μRWell’s before hpDIRC - Impact point and direction for ring seeding oAC-LGAD TOF and AstroPix (BECAL): •Additional space point for pattern recognition / redundancy •Fast hit point / Low p PID Calorimetry Backwards HCal Steel/Sc Sandwich tail catcher Backwards EMCal PbW04 crystals, SiPM photosensors Barrel HCAL Fe/Sc sandwich, ~3.5𝜆 (sPHENIX re-use) Barrel EMCAL 4 (6) layers of imaging calorimetry by Astropix MAPS, and sampling calorimetry by Pb/SciFi Forward EMCal High granularity W/SciFi a unique technology allowing to achieve e/h ~1 (response to hadrons) Forward Hcal SiPMs on tile 36 37 Particle ID Dual-Radiator RICH (dRICH) •C2F6Gas Volume and Aerogel •Single photon sensors (SiPMs) •π/K 3σ sep. at 50 GeV/c AC-LGAD TOF (~30ps) •Accurate space point for tracking / Low p PID •Forward disk and central barrel Proximity Focused (pfRICH) •Aerogel with Long proximity gap (~40 cm) •Sensor: HRPPDs •3𝜎 π/K sep. up to 9 GeV/c High-Performance DIRC •Quartz bar radiator (BaBAR bars) light detection with MCP-PMTs •3𝜎 π/K sep. at 6 GeV/c 38 oWhat machine capabilities can we expect for Early Science? •See Sergei Nagaitzev’s talk in the first Early Science Workshop: https://indico.bnl.gov/event/24432/ oMatrix based on latest news by the Project: •See Elke Aschenauer’s talk at the Collab. Meeting in Frascati: https://agenda.infn.it/event/43344/contributions/250126/ NB: ePIC installation plan calls for the full ePIC to be installed year-1 (exception for roman pots and OMD) EIC Early Science Matrix evolving! 39 oReconstruct inclusive kinematics using various methods •Color of point indicates best method for y (inelasticity) •Size of point indicates y resolution o< 30% y reso. across 𝒙 − 𝑸𝟐 plane ePIC performance: DIS kinematics with ePIC Kinematic Resolutions Key detector performance: •⁄ 𝛾 𝜋separ. in ECAL for DVCS •Acceptance and low material for VM decay leptons •Resol. of lepton pair invariant mass •Scattered electrons over full kinematics •𝑡lever arm in FF spectrometers 40 Real photon (DVCS): •Very clean experimental signature •No VM wave-function uncertainty •Hard scale provided by 𝑸𝟐 •Access to the whole set of GPDs •Sensitive to both quarks and gluons [via Q2 dependence of xsec (scaling violation)] Hard Exclusive Meson Production (HEMP): •Uncertainty of wave function •Hard scale provided by 𝑸𝟐+ 𝑴𝟐 •J/Psi, Y à direct access to gluons, 𝒄O 𝒄, or P 𝒃R 𝒃 pairs produced via 𝒒 𝒈 − 𝒈 fusion •Light VMs à quark-flavor separation •Psedoscalars à helicity-flip GPDs Accessing GPDs in exclusive processes 𝐻UP𝐸UP p 02 D u +D d h 2 D u -D d # 𝐸U # 𝐻U Q2=100 GeV2 Q2=50 GeV2 Planned DVCS at fixed targ.: COMPASSdσ/dt, ACSU, ACST JLAB12dσ/dt, ALU, AUL, ALL Current DVCS data at colliders: ZEUStotal xsec ZEUSdσ/dt H1total xsec H1dσ/dt H1ACU Current DVCS data at fixed targets: HERMESALT HERMESACU HERMESALU, AUL, ALL HERMESAUT Hall ACFFs CLASALU CLASAUL 1 10 10 2 10 3 10-4 10-3 10-2 10-1 1 x Q2 (GeV2) EIC √s= 140 GeV, 0.01≤ y ≤ 0.95 y ≤ 0.6 y ≤ 0.6 EIC √s= 45 GeV, 0.01≤ y ≤ 0.95 Only possible at EIC: from valence quark region, deep into the sea! ρ02u+d, 9g/4 ω2u - d, 3g/4 f s, g ρ+u - d J/ψ, Y g