J-PARC E50. Charmed Baryon Spectroscopy via the (p, D *- ) reactions. Hiroyuki Noumi RCNP, Osaka Univ.

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1 34th REIMEI Workshop on Physics of Heavy-Ion Collisions at J-PARC, August 8-9, 2016 J-PARC E50 Charmed Baryon Spectroscopy via the (p, D *- ) reactions Hiroyuki Noumi RCNP, Osaka Univ. 2

2 Hadron Physics at J-PARC α s = at L QCD Excited State How are they excited? High E Low E How do they change properties in medium? G.S. Quasi-Particles (= Effective DoF) emerging at Low E describe hadron properties effectively. 1

3 Quasi-Particles (Effective EoF) in Hadrons Constituent Quark q q q q q Diquark? (Colored cluster) q q q q q hadron (colorless cluster) [qq] q 3

4 Diquarks Color-Magnetic Interaction of two quarks V CMI ~[a s /(m i m j )]*(l i,l j )(s i,s j ) 0 if m i,j Good Diquark : Strong Attraction V CMI ( 1 S 0, 3 c ) = 1/2*V CMI ( 1 S 0, 1 c ) [qq] [ qq] 4

5 What we can learn from baryons with heavy flavors q qq q q Q Quark motion of qq is singled out by a heavy Q Diquark correlation Level structure, Production rate, Decay properties sensitive to the internal quark(diquark) WFs. Properties are expected to depend on a Q mass. 5

6 Baryon Spectroscopy w/ Heavy Quark Disentangle Quark Correlations in Baryon λ and ρ motions split (Isotope Shift) (qq) r ħω ρ ħω λ = 3m Q 2m q + m Q 3 (m Q ) P-wave ρ mode q q q [qq] Q l λ mode റs HQ ± റj BM Spin-dep. Int. G.S. Q m Q = m q m Q > m q 6

7 Lambda Baryons (P-wave) strange charm bottom L(1830, 5/2 - ) L(1690,?? ) L(1670, 1/2 - ) L(1520, 3/2 - ) L(1405, 1/2 - ) S * (3/2 + ) L(1/2 + ) S(1/2 + ) L(GS) L c (2940,?? ) L c (2880, 5/2 + ) L c or S c (2765,?? ) L c (2625, 3/2 - ) L c (2595, 1/2 - ) S c* (3/2 + ) S c (1/2 + ) L c (GS) L b (5920, 3/2 - ) L b (5912, 1/2 - ) S b* (3/2 + ) S b (1/2 + ) L b (GS) 7

8 Y* - YG.S. [MeV] L(1830, 5/2 - ) L(1690,?? ) L(1670, 1/2 - ) L(1520, 3/2 - ) L(1405, 1/2 - ) S * (3/2 + ) L(1/2 + ) S(1/2 + ) L(GS) Lambda Baryons (P-wave) s r r l c L c (2940,?? ) L c (2880, 5/2 + ) L c or S c (2765,?? ) L c (2625, 3/2 - ) L c (2595, 1/2 - ) S c* (3/2 + ) S c (1/2 + ) L c (GS) MQ [GeV/c 2 ] b l Q L b (5920, 3/2 - ) L b (5912, 1/2 - ) S b* (3/2 + ) S b (1/2 + ) L b (GS) qq r non-rel. QM:H=H 0 +V conf +V SS +V LS +V T r-l mixing (cal. By T. Yoshida) Phys.Rev. D92 (2015)

9 Charmed Baryon Spectroscopy Using Missing Mass Techniques p - p - p - D *- D 0 q D p * eff, D p (p) Y c *+ Production and Decay reflect [qq] correlation C.S. DOES NOT go down at higher L when q eff >1 GeV/c. L K + D 0 (Y c ) 9

10 Production Rate p - D *- u ud D * (q: mom. transfer) L ud p Y c + t-channel D* EX at a forward angle S.H. Kim, A. Hosaka, H.C. Kim, and HN PTEP, (2014) 103D01 c Production Rates are determined by the overlap of WFs R and depend on: 1. Spin/Isospin Config. of Y c 2. Momentum transfer (q eff ) I ~ L 2s exp( iq r) f Spin/Isospin Factor ~ ( q eff - /A) L exp( -q 2 eff / 2A A: (baryon size parameter) -1 ~0.4 GeV/c eff i 2 ) 10

11 Production Cross Section (Regge Theor.) S.H. Kim, A. Hosaka, H.C. Kim, and HN Phys.Rev. D92 (2015) A few nb at p p = 20 GeV/c 11

12 Missing Mass Spectrum (Sim.) ~1000 Y c* /nb/100 days Sensitivity: s ~0.1 nb for Y c* w/ G =100 MeV 1/2+ L = 0 LS partner (HQS doublet) 1/2-3/2-5/2+? 3/2+? L = 1 L = 2 L c (2625) LS partner? (HQS doublet?) s ~1 nb L c L c (2595) L c (2880) S c S c * 1 : 2 S c (2800) L c (2940) 3 : 2 12

13 Y* - YG.S. [MeV] L(1830, 5/2 - ) L(1690,?? ) L(1670, 1/2 - ) L(1520, 3/2 - ) L(1405, 1/2 - ) S * (3/2 + ) L(1/2 + ) S(1/2 + ) L(GS) Lambda Baryons (P-wave) s r r l c L c (2940,?? ) L c (2880, 5/2 + ) L c or S c (2765,?? ) L c (2625, 3/2 - ) L c (2595, 1/2 - ) S c* (3/2 + ) S c (1/2 + ) L c (GS) M Q [GeV/c 2 ] b l Q L b (5920, 3/2 - ) L b (5912, 1/2 - ) S b* (3/2 + ) S b (1/2 + ) L b (GS) qq r non-rel. QM:H=H 0 +V conf +V SS +V LS +V T r-l mixing (cal. By T. Yoshida) 13

14 L c (2765)? Lc(2880)Belle, PRL98, ( 07) L c (2880) L c (2880)->pS c (2455) L c (2940) J=5/2 J =1/2 S c (2455) G(L c (2880)->pS c* (2520)) G(L c (2880)->pS c (2455)) =0.23 L p =1 contribution may affect L p =3 transition S c* (2520) J P =5/2 + for L c (2880) Is it a D-wave Lambda-c Baryon? If so, where is a spin partner?

15 Does L(2880) have L=2? P-wave transition seems to be suppressed in Λ c Σ c π(0 ). It would be forbidden only in the case of J P BM = 3 + : Negative party states 5/2- have large widths. (H. Nagahiro et al., paper in preparation) l Q qq r L c (2880) 5/2+ ll lr rr color Isospin Diquark spin Diquark orbit Asymm. 0 Symm. 0 Asymm. Asymm. (I=0) Symm. 1 Asymm. 1 Lambda orbit J BM P 2+ 1+, 2+, Asymm. 0 Symm, 2 S c* (2520) 3/2+ Asymm Symm. (I=1) Symm. 1 Symm, Λ c is likely to be lr mode (l=1, r=1). It can be tested from its production rate. 15

16 r mode Y c* Decay Pattern Y c * Y c * l mode Y c * D p N G (Yp) >G(DN) G(DN) >G (Yp) 16

17 Y c* Decays Y c * p r l N D L c (2940)->S c0 p + with L c+ p + p - selected L c (2940)-> p D 0 N S ++ c p - psc ~ 200 N psc ~ 200 S 0 (BR psc =13%) c (BR pd =20%) N pd ~ 320 D 0 SUM S c ++ Signal Main BG * Branching ratios: Diquark corr. affects G(L c *->pd)/g(l c *->S c p). 17

18 Counts/sec High-res., High-momentum Beam Line 30 GeV proton beam Production Target High-intensity secondary Pion beam (unseparated) >1.0 x GeV/c High-resolution beam: Dp/p~0.1% 1.0E E E E E E E+03 Prod. Angle = 0 deg. (Neg.) [GeV/c] p - K - p bar T1 Pion Beam Up to 20 GeV/c Spectrometer Sanford-Wang 15 kw Loss on Pt Acceptance :1.5 msr%, m 18

19 High-res., High-momentum Beam Line High-intensity secondary Pion beam >1.0 x GeV/c High-resolution beam: Dp/p~0.1% collection Dispersion QQ QQ QQ D D DDQD QQ (QQQQ) DD S S S Spectrometer Production Target Collimator for Beam Re-define Dispersive Focal Plane For Mom. Meas. Exp. Target 19

20 Spectrometer Design PID counter Muon detector RPC Fiber wall Internal TOF 20 GeV/c Beam p - RPC Pole face detector LH 2 -target T0 Fiber tracker Beam p - Dipole Magnet Internal DC DC 2m TOF wall Ring Image Cherenkov Counter 20

21 Spectrometer Design (Target) Y c *+ Inclusive p(p -,D* - ) Y c * + p(p -,D* - p)d 0 p(p) ( p(p -,D* - p)y c ) D 0 (Y c ) Decay p(p + ) K + p - 20 GeV/c Beam p - Beam p - 2m soft p - Large acceptance ~ 60% (for D*), ~85% (for decay p + ) Good resolution: Dp/p~0.2% at ~5 GeV/c 21

22 High-rate detectors *High-rate beam /spill (30 2 sec spill) Focal plane detector Focal plane region Beam momentum analysis Position and angle Beam tracker At the target upstream Size: 100 mm 100 mm Scattered particle tracker At the target downstream 600 mm 800 mm Experimental area Scattered particle tracker Beam tracker LH 2 target Time zero counter At the target upstream Reference timing for TOF Beam Time zero counter 22

23 Production of prototype detector Fibers fixed to Al frames Al frames are combined by each others. Detector image Extracted fibers are fixed to the MPPC attaching frames. Attaching frame is fixed to Al frames. Plastic frame (similar material to fibers) Air contact with MPPCs Fiber Frame MPPC attaching frame Flat cable MPPC board Readout modules 23

24 Production of prototype detector Fiber Sheet Tech. is well established (M-Line Co.) Glue (Epoxy) Thickness (150mm + 25mm) Detector image PEI sheet (25mm) Fiber Frame MPPC attaching frame Flat cable MPPC board Readout modules 24

25 Large Strip RPC By N. Tomida (RCNP) 2m Long RPC for LEPS2 Signal reflection caused by Impedance Mis-Matching Dispersion during Signal Propagation Transmission Line Theory (D. Gonzalez-Diaz) Change Materials to minimize dispersion during Signal Propagation, changing coupling C to control Signal Propagation Speed 2m 25

26 Large Strip RPC By N. Tomida (RCNP) 2m Long RPC for LEPS2 Signal reflaction caused by Impedance Matching Dispersion during Signal Propagation Transmission Line Theory (D. Gonzalez-Diaz) Before (res. ~ 70 ps) After (res. to be improved) Now Testing at SPring-8 0 2m 26

27 LEPS/J-PARC joint R&D FPGA-based HR-TDC Test Board OPamp comparator out (LVDS) 16 ch DRS4 comparator AD9637 (ADC 12bit, 40MSPS) FPGA Spartan-6 LX150 s t ~20ps (=28/ 2ps) w/ Clock Pulse Test at LEPS analog input (single-end) 16 ch KEK-VME +3.3V -3.3V User I/O (NIM) 100BASE-T DAC (for bias, threshold) By T.N. Takahashi(RCNP) 27

28 Muon ID 28

29 Nucleon Structure via Exclusive DY π p μ + μ "n" T. Sawada, W.C. Chang, S. Kumano, J.C. Peng, S. Sawada, K. Tanaka, Phys.Rev. D93 (2016) ~7 pb 29

30 P c 4380, P c (4450) Is P c + the N* with a hidden c-cbar? P c 0 can be excited on its mass with 10 GeV/c pion beam at J-PARC. Its decay modes to Y c + ഥD. Its family? π ഥD (J/ψ) N P c Y c (n) 30

31 High-speed DAQ system for E50 Frontend modules *Signal digitalization - Pipelined system Streaming DAQ(~50 GB/spill) Buffer PCs *Data accumulation - Several 10 GB memories *High-speed data link (Local) Flexible triggers can be accommodated. ~50 GB/spill Filter PCs *Event reconstruction CPUs <0.5 GB/spill Storage - Local storage - Transferred to KEKCC/RCNP 31

32 ALICE O2 Hardware Facility Sofware R&D (Sako) Load Balancing/Data Flow Regulation R&D (Ma) 32

33 Summary A heavy quark disentangles quark correlation in baryons. A diquark correlation will be singled out in level structure, production rate, and decay branching ratio of excited charmed baryons. Missing mass spectroscopy via p(p -,D *- )Y c* is suitable and unique. The high-momentum beam line and a general purpose spectrometer will provide a unique platform for hadron physics. 33