Jet measurements at the EIC Felix Ringer Lawrence Berkeley National Laboratory RHIC & AGS Annual users meeting, BNL — 10/22/2020 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions The Electron-Ion Collider January 9, 2020 • High luminosity 33 34 2 1 10 − cm− s− • Center-of-mass energy ps = 20 140 GeV − • Highly polarized beams • Electron-proton/nucleus collisions … 2010 2015 2018 2020 2 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions The EIC science program • The spin and mass of the proton • 3D imaging • Parton distribution functions Transverse momentum (TMDs) and position (GPDs) 1 1 = ⌃(Q2)+∆G(Q2)+L (Q2)+L (Q2) 2 2 q g 1 1 = ⌃(Q2)+∆G(Q2)+L (Q2)+L (Q2) ~ 2 2 q g • Small-x and saturation • Hadronization • Nuclear modification in eA collisions 3 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions The EIC science program with jets Jets as tools to realize the EIC science goals — Recent publications • The spin of the proton, PDFs Hinderer, Schlegel, Vogelsang `15, `17, Abelof, Boughezal, Liu, Petriello `16, Boughezal, Petriello, Xing `18, Aschenauer, Chu, Page `19, Guzey, Klasen `18, `20, Borsa, Florian, Pedron `20, `20, Arratia, Furletova, Hobbs, Olness, Sekula `20 • 3D nucleon/nucleus tomography Zheng, Aschenauer, Lee, Xiao, Yin `18, Liu, FR, Vogelsang, Yuan `19, Gutierrez-Reyes, Scimemi, Waalewijn, Zoppi `19, Hatta, Mueller, Ueda, Yuan `19, Arratia, Kang, Prokudin, FR `20, Kang, Liu, Mantry, Shao `20, Castillo, Echevarria, Makris, Scimemi `20 • Saturation, a new form of gluon matter Hatta, Xiao, Yuan `17, Salazar, Schenke `19, Roy, Venugopalan `19, Kang, Liu `19 Kolbe, Roy, Salazar, Schenke, Venugopalan `20 • Hadronization and quarks and gluons in the nucleus Klasen, Kovarik `18, Aschenauer, Lee, Page, FR `19, Qin, Wang, Zhang `19, Arratia, Song, FR, Jacak `19, Li et al. `20, Barata, Mehtar-Tani, Soto-Ontoso, Tywoniuk `20, Li, Vitev `20 4 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions The EIC science program with jets total number of EIC jet papers • There have been many new developments recently! • Prominently featured in the EIC Yellow Report 5 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jets at the EIC Jet transverse momentum Number of particles Relatively low energies, need good control of hadronization corrections Clean environment — no Multi Parton Interactions (MPI) 6 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jets at the EIC Q2 > 100 GeV2, ps = 89 GeV e 10 <pT < 30 GeV, 0.1 <y<0.85 rapidity ⌘ rapidity ⌘ initial proton particle momentum initial proton Hadron Struck quark Jets Jets are excellent proxies of parton level kinematics Clean separation of current & target fragmentation (UE) Complementary to observables with hadrons Arratia, Jacak, FR, Song `19 Laboratory frame Pythia 8 see also Aschenauer, Chu, Page `19 7 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions The QCD fragmentation process • Fragmentation functions de Florian, Epele, Hernandez-Pinto, Sassot, Stratmann `15 10 pT = 100 GeV 8 ) • Jet functions R T 6 R =0.7 z,p ( g 4 J 2 Kang, FR, Vitev `16 0 Dai, Kim, Leibovich `17 0 0.2 0.4 0.6 0.8 1 Neill, FR, Sato `20 z = pT /pˆT 8 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Outline • Introduction • Inclusive and leading jets • TMDs measurements with jets • Hadronization and cold nuclear matter • Conclusions 9 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jet clustering and frame dependence • Laboratory frame e0(k0) e(k) Can measure two variables 2 2 2 2 Q =(k k0) • Jet transverse momentum pT ,Q• Photon virtualitypT ,Q − 2 Leading electronpT ,Q 2 pT ,Q • Cluster jets in the laboratory frame ⌘, φ • Leading-order eq eq ! 10 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jet clustering and frame dependence e0(k0) • Laboratory frame e(k) 2 2 2 Measure only p T ,,Q close analogy to pp jet + X Q =(k k0) ! − NLO NNLO 2 pT ,Q Hinderer, Schlegel, Vogelsang `15 Abelof, Boughezal, Liu, Petriello `16 11 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jet clustering and frame dependence e0(k0) • Laboratory frame e(k) 2 2 2 Measure only p T ,,Q close analogy to pp jet + X Q =(k k0) ! − Double longitudinal spin asymmetries ∆qi , ∆g 2 ~e + p~ jet + X ~e + p~ e +jet+X pT ,Q ! ! NLO Boughezal, Petriello, Xing `18 Borsa, Florian, Pedron `20 see also Hinderer, Schlegel, Vogelsang `17 12 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Jet clustering and frame dependence Arratia, Makris, Neill, FR, Sato `20 • Breit frame 2 • Photon virtualitypT ,Q • Jet energy Inclusive jets Breit frame ps = 63 GeV ,Q>10 GeV Pythia σ NLL NP d ⌦ R =0.8 • Reconstruct jets which enclose the Breit frame beam axis • Starting point for Breit frame TMD-jet studies 13 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Leading jets Neill, FR, Sato `20 • Inclusive vs. leading jets • The average energy loss R z =1 z loss − 1 14 + Introduction Inclusive and leadinge e− jets TMDs Hadronization & CNM Conclusions Outline • Introduction • Inclusive and leading jets • TMDs measurements with jets • Hadronization and cold nuclear matter • Conclusions 15 + Introduction Inclusive and leadinge e− jets TMDs Hadronization & CNM Conclusions TMD-jet observables Gutierrez-Reyes, Scimemi, Waalewijn, Zoppi `18, `19 • Semi-Inclusive Deep Inelastic Scattering Gutierrez-Reyes, Makris, Vaidya, Scimemi, Zoppi `20 • Breit frame jet reconstruction e + p e +jet+X ! dσep eJX ! = H f (x, q) J (z,q,R) dQ2dxdzdq DIS q ⌦q q q X Perturbative TMD jet function • Sensitivity to TMD PDF only • Winner-take-all (WTA) jet axis 16 + Introduction Inclusive and leadinge e− jets TMDs Hadronization & CNM Conclusions TMD-jet observables Gutierrez-Reyes, Scimemi, Waalewijn, Zoppi `18, `19 • Semi-Inclusive Deep Inelastic Scattering Gutierrez-Reyes, Makris, Vaidya, Scimemi, Zoppi `20 • Breit frame jet reconstruction e + p e +jet+X ! WTA-axis 17 + Introduction Inclusive and leadinge e− jets TMDs Hadronization & CNM Conclusions Electron-jet correlations Liu, FR, Vogelsang, Yuan `18, `20 Arratia, Kang, Prokudin, FR `19 e jet • Measure the electron-jet imbalance ~qT = p~T + p~T • Sensitivity to TMD PDFs only • Sivers asymmetry σ(S~ ) σ( S~ ) T − − T ⌘ jet p~T S~T e p ~qT e p~T ejet p~T • Test of the predictive power of QCD — di-jet processes at RHIC 18 + Introduction Inclusive and leadinge e− jets TMDs Hadronization & CNM Conclusions Electron-jet correlations - flavor sensitivity e jet Liu, Kang, Mantry, Shao `20 • Measure the electron-jet imbalance ~qT = p~T + p~T • and the jet charge Qi = Qh zQ Field, Feynman `78 ⌘ h h h h jet X X2 (weighted sum of charges) • Jet charge tagging avoids large cancellation between different quark flavors σ(S~ ) σ( S~ ) T − − T jet p~T S~T e p ~qT e p~T see also Krohn, Lin, Schwartz, Waalewijn `12, ejet Waalewijn `12, p~T 19 RHIC measurements + Introduction Inclusive and leading jets TMDs HadronizationeWe±− & CNM Conclusions Outline • Introduction • Inclusive and leading jets • TMDs measurements with jets • Hadronization and cold nuclear matter • Conclusions 20 + Introduction Inclusive and leading jets TMDs HadronizationeWe±− & CNM Conclusions Probes of cold nuclear matter effects in eA • Electron-jet correlations • Transverse momentum broadening jet GW - Gyulassy Wang p~T Probability distribution e p ~qT e p~T Barata, Mehtar-Tani, Soto-Ontoso, Tywoniuk `20 Liu, FR, Vogelsang, Yuan `18, `20, ejet Arratia, Jacak, FR, Song `19 p~T 21 + Introduction Inclusive and leading jets TMDs HadronizationeWe±− & CNM Conclusions Probes of cold nuclear matter effects Li, Vitev `20 • Inclusive jet production e + A e +jet+X ! Medium modified jet function approach µ med 2 med Jq (z,pT R, µ)= d k fq qg (z,k ) + ... z(1 z)p R ? ! ? "Z − T #+ 22 + Introduction Inclusive and leading jets TMDs HadronizationeWe±− & CNM Conclusions Do we need to measure jets at the EIC? Neill `20 h • Evolve jet functions to a nonperturbative scale (~1 GeVD i~( ⇤ QCD ) • Small-z resummation + Local parton hadron duality • The only fitted parameter is the cutoff scale (& partly the normalization) Hi(pT ) pT R h Di (⇤QCD) 23 + Introduction Inclusive and leading jets TMDs HadronizationeWe±− & CNM Conclusions Do we need to measure jets at the EIC? Neill `20 h • Evolve jet functions to a nonperturbative scale (~1 GeVD i~( ⇤ QCD ) • Small-z resummation + Local parton hadron duality • The only fitted parameter is the cutoff scale (& partly the normalization) Hi(pT ) pT R h Di (⇤QCD) … this suggests • Hadrons are simply jets with a nonperturbative radius • The more fundamental objects are jets/jet functions • Most of the QCD fragmentation process is perturbative — do we still need fragmentation functions? 24 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Outline • Introduction • Inclusive and leading jets • TMDs measurements with jets • Hadronization and cold nuclear matter • Conclusions 25 Introduction Inclusive and leading jets TMDs Hadronization & CNM Conclusions Conclusions • Growing field of jet physics at the EIC • Relevant for all parts of the EIC science program • Jet physics part of the EIC Yellow Report • Potential impact on detector design • Many new opportunities • STAR, sPHENIX, HERA 23-25 Nov https://indico.bnl.gov/event/8066/overview 26.