with high-momentum hadron beams K. Shirotori for the E50 - PowerPoint PPT Presentation

Hadron spectroscopy with high-momentum hadron beams K. Shirotori for the E50 collaboration Research Center for Nuclear Physics (RCNP) Osaka University The 3rd J-PARC symposium (J-PARC2019) 26 th September 2019

2 Contents • Motivations of hadron physics • Effective degree of freedom of hadrons • Hadron property in medium • J-PARC Facility • J-PARC high-momentum beam line • Multi-purpose spectrometer system • K10 beam line and Hadron hall extension • Summary

Motivations of Hadron Physics

4 Hadron physics investigations • Excited states • Effective degree of freedoms • Constituent quark + Diqaurk correlation & Hadron molecule ⇒ Spectroscopy experiment with heavy quark • Excites energy, spin and parity, production cross section, decay branching ratio • Properties in nuclear medium • Origin of mass • Spontaneous breaking of chiral symmetry ⇒ Measurement on nuclear target • Change of mass, shape, decay branching ratio, cross section ＊ J-PARC: High-intensity Secondary Hadron beams

5 Excited states: Observation of exotic hadrons q Meson Baryon ͞ q Constituent quark q q q Hadron molecule Multi-quark ͞ q q q ͞ q Exotic hadrons q q q q q q ＊ Excited states: Rich properties ⇒ Mass, width, decay branching ratio, spin and parity from new effective degree of freedoms extended to ordinary constituent quark model

6 Excited states: Observation of exotic hadrons q Meson Baryon ͞ q Constituent quark q q q Hadron molecule Multi-quark ͞ q q q ͞ q Exotic hadrons q q q Diquark q q q correlation q-q Diquark correlation & Hadron molecule q

7 Excited states with heavy quark: Diquark “ Excited mode ” : l and r modes in heavy baryon excited states ( q-q + Q system) ⇒ Diquark correlation: q-q isolated and developed r mode q-q Light quark baryon Excitation of q-q Excited states q by spin-spin interaction q Q ⇒ Observables q q-q l mode Corrective motion btw q-q and Q Q G.S.

8 Charmed baryon spectroscopy experiment: J-PARC E50 Excited states with heavy quark: Diquark ＊ p - + p → Y c *+ + D * - reaction @ 20 GeV/c “ Excited mode ” : l and r modes in charmed baryon excited states ( q-q + system) High-intensity p - beam: 6.0 × 10 7 /spill • ⇒ Diquark correlation from Production rate and Decay branching ratio • Production rates & Decay branching ratios r mode q-q Light quark baryon Excitation of q-q Excited states q by spin-spin interaction q ⇒ Observables c q q-q l mode Corrective motion btw q-q and Q c G.S.

9 Production rates by hadronic reaction • p - + p → Y c *+ + D * - reaction: Missing mass method ＊ Production cross section ⇒ Overlap of wave function ＊ Production rates ⇔ Internal structure of excited states ＊ charm and q-q (spectator) ⇒ Selective production of corrective motion: l mode      R ~ 2 exp( i q r ) - f eff i Reaction diagram Simulation L c (2595) L c (2625) L c (2880) L c @ 1 nb L c (2940) S c (2800) S c (2520) S c (2455) 1 : 2 3 : 2 ＊ Angular momentum transfer between diquark ( q-q ) and charm quark S.H. Kim, A. Hosaka, H.C. Kim, H. Noumi, K. Shirotori Prog. Theor. Exp. Phys. 103D01 (2014).

10 Excitation spectrum: q-q + Q P-wave states Strange baryons Charmed baryons s c 800 r L (1/2 - , 3/2 - , 5/2 - ) 700 L c (1/2 - , 3/2 - , 5/2 - ) r L c (1/2 - , 3/2 - ) 600 Y* - Y G.S. [MeV] L (1/2 - , 3/2 - ) 500 l L (1/2 - , 3/2 - ) 400 L c (1/2 - , 3/2 - ) S (3/2 + ) 300 S c (3/2 + ) 200 S c (1/2 + ) S (1/2 + ) 100 L c (1/2 + ) L (1/2 + ) 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 M Q [MeV/c 2 ] • Non-rel. QM: H = H 0 + V conf + V SS + V LS + V T ＊ Heavy quark sector (charm) l - r mixing • ⇒ Light quark sectors (u, d, s) (cal. By T. Yoshida, Nucl.Phys. A954 (2016) 341)

11 Strange baryon systems L * /S * q-q • L * / S * : q-q + Q system ⇒ Systematics with charmed baryon Production rate: l and r selection • Q • Decay branching ratio • X * : q + QQ system X * Q Q ⇒ Excitation with two heavy quarks • W * : QQQ system q ⇒ Same weight of three heavy quarks ＊ Spectroscopy by high-momentum K - beam Q W * Q • Several GeV/c beam • Poor data of X and W states • Exotic states Q ⇒ Systematic measurement

12 Hadron in nuclear medium • Properties in finite density f / w / r • Origin of hadron mass ＊ Spontaneous breaking ⇒ Vector mesons of chiral symmetry • Quark condensation: <qq bar > ＊ Different mesons: ＊ Mass shift in medium Different aspect on QCD vacuum Chiral origin ~ Constituent mass h / h ’ • Experimental signals on nuclear target • Mass spectrum: Shift & Shape change U A (1) anomaly + SBCS • Decay branching ratio • Production cross section • A-dependence • Quark configuration: Light and heavy quarks

13 Experimental approaches • DD bar production at threshold region • c/c bar : No effect • q/q bar : Change of mass ⇒ Cross section in medium • p bar + p → D + D bar ⇔ p bar + A → D + D bar + X D ≠ D bar ＊ Effects to q/q bar w/o other light quarks • Charmonium states T [GeV] Mass reduction Mass gain ⇒ Access to gluon condensation • Mass shape (Production cross section) • Decay branching ratio ⇒ Suppression of decay modes • p bar + A → M(cc bar ) + X • Ex. M(cc bar ) → DD bar mode forbidden ＊ High-momentum p bar beam on nuclear target • Several GeV/c beam • Fixed target experiment Gy. Wolf at al., PLB 780, 25-28, 2018

14 Question to hadron/nuclear physics 10 4 m 10 - 14 m Effective degree of freedom and origin of mass q q q Quark ・ Gluon Nucleus Hadron Neutron star • Neutron star: High-density nuclear matter • Quark ・ Gluon → Hadron → Hadron interaction → Nucleus → Neutron Start ＊ Hadron properties: Effective degree of freedom, origin of mass • Roles of light quarks (u, d, s) from studies of heavy quark (charm) @ J-PARC

J-PARC Facility High-momentum beam line Hadron hall extension: K10 beam line

High-momentum beam line for 2 ndary beam 16 • High-intensity beam: > 1.0 × 10 7 Hz p (< 20 GeV/c) • Unseparated beam: p /K/p bar • High-resolution beam: D p/p ~ 0.1%(rms) • Momentum dispersive optics method Exp. Target (FF) Collimator Production Target Focal Point (IF) (SM)

High-momentum beam line for 2 ndary beam 17 ~100 mm • High-intensity beam: > 1.0 × 10 7 Hz p (< 20 GeV/c) • Unseparated beam: p /K/p bar • High-resolution beam: D p/p ~ 0.1%(rms) • Momentum dispersive optics method Design Intensity [/spill (5.2 sec)] @ 15 kW loss 1.0E+09 • Size: 100 mm × 100 mm p - 1.0E+08 Several 10 7 /spill • 1 MHz / 1 mm p • 6.0 × 10 7 /spill (30 MHz) 1.0E+07 p + @ 20GeV/c 1.0E+06 K - Several 10 5 /spill 1.0E+05 K + p bar 1.0E+04 0 2 4 6 8 10 12 14 16 18 20 [GeV/c]

18 Charmed baryon spectrometer PID counter K + Fiber wall Internal TOF p + p - Pole face detector Ring Image p s - LH 2 -target Cherenkov Counter T0 TOF wall p - DC Fiber tracker Beam p - Internal DC 2m

19 Charmed baryon spectrometer PID counter K + Fiber wall Internal TOF p + Large Acceptance Multi-Purpose Spectrometer p - + Trigger – less DAQ system Pole face detector Ring Image p s - Charmed baryon spectrometer LH 2 -target Cherenkov Counter ⇒ New platform for Hadron experiment T0 TOF wall p - DC Fiber tracker Beam p - Internal DC 2m

20 Beam intensity for K and p bar experiment • Several GeV/c beam for X * / W * , DD bar and charmonium • > 1 MHz K/p bar beam ⇔ > 100 MHz p beam • Beam measurement is bottleneck. ⇒ Dedicated K/p bar beam line K/ p & p bar / p ratio Design Intensity [Hz] in spill (2.0 sec) 2.E-02 1.0E+09 2% p - 1.0E+08 2.E-02 K - /p- 1.0E+07 MHz K beam 1.E-02 K - 1.0E+06 p bar 5.E-03 1.0E+05 p bar /p- 1.0E+04 0.E+00 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 12 14 16 18 20 @ 15 kW loss [GeV/c] [GeV/c]

21 Hadron hall extension

22 Hadron hall extension

23 Conceptual design of Di-muon spectrometer K10 beam line • Separated K/p bar beams up to 10 GeV/c • RF separator ⇒ ~10 7 /spill beam ＊ High intensity, purity and momentum hadron beams

24 Summary ＊ Key: Hadron with heavy quark _ q-q • Motivations of hadron physics q • Effective degree of freedom of hadrons • Spectroscopy of excited states • Properties in finite density Q Q • Measurement of hadron properties in nuclear medium • Experimental approaches to understand hadrons • Spectroscopy of hadrons with heavy quarks • Charmed baryon, X * and W * • Meson in nuclei • Vector meson( f ), DD bar , Charmonium • J-PARC facility: High-intensity & High-momentum hadrons beams • High-momentum beam line • Unseparated beam • Multi-propose spectrometer • K10 beam line in extended hadron hall • Separated K/p bar beams