Electron-scattering constraints for neutrino-nucleus interactions Lawrence Weinstein Old Dominion University NUSTEC 2019
Collaboration • Michigan State • Old Dominion University • FermiLab • MIT • Pitt • Jefferson Lab • York University, UK • Tel Aviv U Mariana Khachatryan Afroditi Papdopolou Adi Ashkenazi Florian Hauenstein (ODU) (MIT) (ODU) (MIT) L. Weinstein, NUSTEC 2019 + Minerba Betancourt (FNAL) + Lucas Tracy (ODU)
Outline • Why electrons? – Nuclear Physics • Current work – Zero pion channel (updated) – One pion channel (new) • Future plans L. Weinstein, NUSTEC 2019
Why electrons? • Known incident energy 𝑚 ' 𝜉 4 W + • High intensity n p • Similar interaction with nuclei – Single boson exchange – CC Weak current [vector plus axial] ± = % + + (𝛿 " − 𝛿 " 𝛿 / )𝑣 𝑣 '() * • 𝑘 " 𝑓 ' 𝑓 ' – EM current [vector] 12 = % 𝑣 𝛿 " 𝑣 • 𝑘 " p p • Similar nuclear physics L. Weinstein, NUSTEC 2019
Nuclear Physics d σ Dip d ω or ν L. Weinstein, NUSTEC 2019
Nuclear Physics d σ Dip d ω or ν What neutrino expts want L. Weinstein, NUSTEC 2019
Nuclear Physics d σ Dip d ω or ν What we get (even for 0pi) Meson Final State Short Range Resonance Exchange Interactions Correlations Currents L. Weinstein, NUSTEC 2019
How do reaction mechanisms appear in A(e,e’p)? ?? Single nucleon knockout Undetected pion Undetected Undetected 2 nd nucleon 2 nd nucleon Missing energy (MeV) L. Weinstein, NUSTEC 2019
From QE to “dip” C(e,e’p) 𝜕 = 0.2 𝜕 = 0.2 GeV 0.6 GeV/c 0.4 GeV/c 𝜕 = 0.2 x ~ 2 x ~ 1 dip Missing energy [MeV] 𝑦 = 𝑅 + Dip 2𝑛𝜕 R. Lourie, PRL 56 , 2364 (1986) L. Weinstein, PRL 64 , 1646 (1990) S. Penn, PhD thesis, MIT L. Weinstein, NUSTEC 2019
From Dip to Delta Region C(e,e’p) q = 400 MeV/c q = 473 MeV/c ω = 275 MeV/c ω = 382 MeV/c Δ è π p Δ è π p Δ N è pN or 2p2h Δ N è pN Missing Energy (MeV) Missing Energy (MeV) Dip Baghaei, PRC 39 , 177 (1989) L. Weinstein, NUSTEC 2019
What are correlations? Average Two-Nucleon Properties in the Nuclear Ground State Responsible for the high momentum part of of the Nuclear WF Two-body currents are not Correlations (but everything adds coherently) ! ! in SRC L. Weinstein, NUSTEC 2019
2N currents enhance correlations Central correlations only Central + tensor corr 12 80 σ σ 1250 σ MEC and correlations add coherently 360 → 2𝑞2ℎ E m 90 30 0 θ pq Corr + MEC O(e,e’p) Ryckebusch NP A672 (2000) 285 L. Weinstein, NUSTEC 2019
Physics Summary • Electron scattering: – Monochromatic beam – Vector current only – Can choose kinematics to minimize “uninteresting” reaction mechanisms – Calculate cross sections after the fact • Neutrino interactions – Continuous mixed beams – Vector plus axial current – Must include all reaction mechanisms • MEC, IC, correlations, Delta, … • FSI (not discussed here) – Need good models in event generators L. Weinstein, NUSTEC 2019
Jefferson Lab data CLAS6: 1996-2015 TOF CAL CER DC3 DC2 DC1 L. Weinstein, NUSTEC 2019
CLAS6 (e,e’p) Data (million events) 1.1 GeV 2.2 GeV 4.4 GeV 3He 4 9 1 4He X 17 3 12C 3 11 2 56Fe X 0.5 0.1 E2a data only. E2b has more 4.6 GeV 3He and 56Fe 0.8 T2K off-axis flux 𝜉 𝜈 Flux [Arb.] 0.7 Eg2 has 5 GeV d, C, Al, Fe, and Pb T2K on-axis flux MiniBooNE flux 0.6 ν NO A near detector flux 0.5 ν MINER A flux 0.4 0.3 0.2 0.1 0.0 0 1 2 3 4 5 6 0 1 2 3 4 5 6 E 𝜉 [GeV] L. Weinstein, NUSTEC 2019
Reconstructing the initial energy • Choose 0 𝜌 events to enhance the QE sample – Subtract undetected pions and photons • Weight by 1/𝜏 FGHH to account for photon propagator • Reconstruct the incident lepton energy: P +F L MN+F L K O '2 O – 𝐹 JK = +(F L 'K O NQ O RGST O ) • 𝜗: nucleon separation energy, 𝑁 X nucleon mass • {𝑛 4 , 𝐹 4 , 𝑙 4 , 𝜄 4 } scattered lepton mass, energy, momentum and angle • broadened by nucleon fermi motion a + 𝜗 [for (e,e’p) ] – 𝐹 R^4 = 𝐹 1 + 𝑈 L. Weinstein, NUSTEC 2019
CLAS6 coverage 𝑞 2(b ≈ 150 MeV/c 𝑞 2(b ≈ 300 MeV/c L. Weinstein, NUSTEC 2019
Exclude radiated photons 𝛿 from Batman Radiated 𝛿 𝛿 from 𝜌 f 𝛿 from 𝜌 f L. Weinstein, NUSTEC 2019
Background Subtraction Want 0𝜌 event sample (e,e’) background: undetected pions and photons (e,e’p) background: undetected pions, photons and extra protons Data Driven Correction: 1. Use measured (e,e’p 𝜌 / 𝛿 ) events, 2. Rotate 𝜌 or 𝛿 around q to determine its acceptance, 3. Subtract (e,e’p 𝜌 / 𝛿 ) contributions
Background Subtraction Want 0𝜌 event sample (e,e’) background: undetected pions and photons (e,e’p) background: undetected pions, photons and extra protons Data Driven Correction: 1. Use measured (e,e’p 𝜌 / 𝛿 ) events, 2. Rotate 𝜌 or 𝛿 around q to determine its acceptance, 3. Subtract (e,e’p 𝜌 / 𝛿 ) contributions 4. Do the same for 2p, 3p, 2p+ 𝜌 etc. pion multiplicity Proton multiplicity 2.2 GeV 12 C 2.2 GeV 12 C 0 1 2 3 0 1 2 3 N π ± N p
Background Subtraction Want 0𝜌 event sample (e,e’) background: undetected pions and photons (e,e’p) background: undetected pions, photons and extra protons Data Driven Correction: 1. Use measured (e,e’p 𝜌 / 𝛿 ) events 2. Rotate 𝜌 or 𝛿 around q to determine its acceptance, Detected 1 𝜌/𝛿 3. Subtract (e,e’p 𝜌 / 𝛿 ) contributions Undetected 1 𝜌/𝛿 4. Do the same for 2p, 3p, 2p+ 𝜌 etc. Undet 2 𝜌/𝛿 pion multiplicity Proton multiplicity 2.2 GeV 12 C 2.2 GeV 12 C 0 1 2 3 0 1 2 3 N π ± N p
Background Subtraction Want 0𝜌 event sample (e,e’) background: undetected pions and photons (e,e’p) background: undetected pions, photons and extra protons Data Driven Correction: No cuts 1. Use measured (e,e’p 𝜌 / 𝛿 ) events 2. Rotate 𝜌 or 𝛿 around q to No det. 𝜌/𝛿 determine its acceptance, 3. Subtract (e,e’p 𝜌 / 𝛿 ) contributions 4. Do the same for 2p, 3p, 2p+ 𝜌 etc. sub 𝜌 subtract 𝜌/𝛿 pion multiplicity Proton multiplicity 2.2 GeV 12 C 2.2 GeV 12 C 0 1 2 3 0 1 2 3 True 0𝜌 event sample! N π ± N p
Energy Reconstruction: A dependence 2.26 GeV beam Zero pion events 4 He 56 Fe E Cal (e,e’p) E Cal (e,e’p) Preliminary E QE (e,e’) E QE (e,e’) E QE (e,e’p) E QE (e,e’p) 0 0.5 1 1.5 2 2.5 3 0 0.5 1 1.5 2 2.5 3 E rec [GeV] E rec [GeV] Even 0pi events have a LOT of non-QE events • Much bigger in Fe than 4 He • Same long tail for E cal and E QE • L. Weinstein, NUSTEC 2019
Agreement between methods does not guarantee correctness Good reconstruction Bad reconstruction good agreement Calorimetric method QE (lepton only) method L. Weinstein, NUSTEC 2019
Fractional Energy Feeddown QE (e only) calorimetric 12 C 4.4 GeV Preliminary 2.2 GeV 1.1 GeV 56 Fe 4.4 GeV 2.2 GeV L. Weinstein, NUSTEC 2019
Can we select QE events? 2.2 GeV 56 Fe 3 ⊥ = P ⊥ + P p ⊥ ≈ P 2.5 ⊥ 2.5 P E QE [GeV] e − miss init 𝑓 h 2 g 2 𝑞 2(SS e 1.5 1.5 p 1 1 0.5 0.5 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0 0.2 0.4 0.6 0.8 1 miss [ GeV / c ] P ⊥ L. Weinstein, NUSTEC 2019
⊥ s lices P miss E QE E Cal 3 E QE 2.5 0-0.2 4 He 2 >0.4 1.5 0.2-0.4 1 0.5 Preliminary 12 C 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 ⊥ P miss 0-0.2 56 Fe >0.4 g High 𝑞 2(SS 0.2-0.4 → wrong energy! E QE [GeV] E Calor [GeV]
0𝜌 Data vs Genie 2.2 GeV C(e,e’p) 2.26 GeV Q 2 (GeV 2 ) Data GENIE 1.5 1.0 0.5 Preliminary 1.0 0.5 1.5 1.0 0.5 1.5 Energy Transfer Energy Transfer 2 x = 1.2 1.8 B Q 2 (GeV 2 ) 1.6 1.5 ) 1.4 /c 0𝜌 does not mean QE! (GeV 1.2 1.0 x = 0.8 1 B Q GENIE 0.8 No resonance! 0.6 0.5 0.4 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 0.5 1.0 Energy Transfer (GeV) Energy Transfer L. Weinstein, NUSTEC 2019
0𝜌 Data vs GENIE Preliminary C 4.4 GeV C 2.2 GeV Data GENIE Data GENIE 0.5 1 0 0 0.5 1 2(SS [GeV/c] 2(SS [GeV/c] 𝑞 g 𝑞 g L. Weinstein, NUSTEC 2019
0𝜌 Data vs GENIE: Carbon Preliminary Data: dashed GENIE: solid 4.4 GeV 2.2 GeV 1.1 GeV Fractional energy feed down L. Weinstein, NUSTEC 2019
0𝜌 Data vs GENIE: Iron Data: dashed GENIE: solid 4.4 GeV Preliminary 2.2 GeV Fractional energy feed down L. Weinstein, NUSTEC 2019
0𝜌 GENIE energy recon 12 C(e,e’p) 2.2 GeV The tail is entirely RES + DIS L. Weinstein, NUSTEC 2019
Data vs Genie: E beam Reconstruction e - Data 𝒇 GENIE Fe 2.2 GeV 26% 29% 4.4 GeV 16% 21% Fraction of Fe( 𝑓, 𝑓 h 𝑞 ) events with E Cal within 5% of E beam L. Weinstein, NUSTEC 2019
Apply QE CLAS data to DUNE Oscillation DUNE Far Detector Truth 𝜉𝐵 GENIE Preliminary eA data 2 4 6 Reconstructed E 𝜉 [GeV] • Threw events with 𝜉𝐵 Genie • Reconstructed with 𝜉𝐵 GENIE or eA data • Compared E rec for eA to E rec for 𝜉𝐵 L. Weinstein, NUSTEC 2019
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