1. J-PARC Heavy ion program and related topics K. Ozawa (KEK)

2. 03/Dec/2015K. Ozawa2 Tokyo ECT* 10000km

3. 03/Dec/2015K. Ozawa3 J-PARC Tokyo 150km Tsukuba Univ. KEK Narita

4. 03/Dec/2015K. Ozawa4 J-PARC (Japan Proton Accelerator Research Complex) Tokai, Japan MR 30 GeV Synchrotron 400 MeV Linac RCS 3 GeV Synchrotron Material and Life Science Facility Neutrino Experimental Facility Hadron Hall 60m x 56m Hadron Experimental Facility

5. 30 GeV Accelerator & Hadron Experimental Facility 03/Dec/2015K. Ozawa5 30GeV proton Accelerator Branch Point from Acc. to Hadron Transfer Line from Acc. to Hadron Hadron Experimental Facility Current Production target for secondary beams New Beamline (under construction) North Side South Side

6. K. Ozawa6 Hadron Experimental Facility K1.8BR KL K1.8 K1.1 High-p COMET NameSpeciesEnergyIntensity K1.8  ±, K ± < 2.0 GeV/c~10 5 Hz for K + K1.8BR  ±, K ± < 1.0 GeV/c~ 10 4 Hz for K + K1.1  ±, K ± < 1.1 GeV/c~ 10 4 Hz for K + High-p proton30GeV~ 10 10 Hz Unseparated< 20GeV/c~ 10 8 Hz 03/Dec/2015 Under Construction Production Target

7. New Beam Line Construction of New Beam Line is proposed as a high priority plan of the lab. Characteristics of the beam line is following. Primary Proton Beam (30GeV), 10 10 per spill High Momentum un-separated secondary beam (< 20GeV/c), 10 8 per spill Primary Proton Beam (8GeV) for COMET The new beam line will be operated in 2017. Physics Vector mesons in nucleus Charmed Baryon and hadron structure mu-e conversion (COMET) 03/Dec/20157K. Ozawa New Beam Line

8. New Beam Line – Physics Program 03/Dec/2015K. Ozawa8 Primary Proton Beam pA reaction Vector meson spectra via Di- electron measurements* Secondary Beam  A reaction Exclusive measurements Resonance Study Charmed Baryon Heavy Ion Beam AA reaction Vector meson in high density matter * Details will be presented by K. Aoki on Friday

9. High momentum secondary beam New beam line will be used as a high momentum secondary beam line which delivers un-separated secondary beam. Main component is  mesons K mesons and protons are also contained Physics Di-lepton measurements Charmed baryon spectroscopy 03/Dec/2015K. Ozawa9

10. Measurements of Vector mesons Mass spectra of vector mesons in finite temperature or density matter have essential information. However, dynamics of reactions always causes model dependent issues. I proposed a new experiment to measure mass spectra of vector mesons in nucleus with an exclusive condition to minimize such difficulties. 03/Dec/2015K. Ozawa10   A   /  + p+X e+e-e+e-   e+e+ p e-e- Elementary Reaction:  + + n (in A)   + p We can measure  (beam),  (decays), emitted proton (Forward spectrometer) The reaction dynamics can be identified by these measurements.

11.  at rest In addition, when we choose a momentum of the incident beam carefully, we can generate  mesons “at rest”. Note: Due to a Fermi motion and experimental effects,  mesons still have small momentum. 03/Dec/2015K. Ozawa11 Elementary reaction  + + n (in A)   + p Forward emitted proton carries momentum of incident beam and generated w meson has small momentum We can measure mass spectra in nucleus at “p  0”.

12. Other physics examples Precise measurements of resonance effects HADES pointed out that Nucleon resonance states have a significant role in e + e - mass spectrum in  mass region In addition, relatively high momentum  beam can probe a structure of N*  interference and mass modification M.F.M. Lutz, B. Friman, M. Soyeur calculated effects of r/w interference on di-lepton mass spectra 03/Dec/2015K. Ozawa12 Nucl. Phys, A713(2003), 97

13. J-PARC HI Project MR RCS HI booster HI LINAC U 35+ 20.0MeV/u U 55+ →U 66+ 19.86→67.0 MeV/u U 86+ 62.34→735.21 MeV/u U 66+ →U 86+ 67.0→62.34 MeV/u U 86+ →U 92+ 735.21→727.0 MeV/u U 92+ 727.0Mev/u→11.15 GeV/u (30GeV@p) stripping U 35+ →U 55+ 20.0→19.86 MeV/u 1303/Dec/2015K. Ozawa Acceleration Scheme for Uranium case(Proposed by H. Harada, J-PARC) New LINAC and Booster for HI must be constructed.

14. J-PARC Heavy Ion specification 14 “Low energy” program (Linac) for unstable nuclei research Ion species – Ne, Ar, Fe, Ni, Kr, Xe,…,U Beam energy – 1 - 10 AMeV (U) Beam current – 10-30 p  A – 10ms, 25Hz 03/Dec/2015 K. Ozawa

15. /0/0 Calculated by JAM model, Y. Nara, Phys. Rev. C61,024901(1999) Physics Study of High Density Matter – Strange meson and baryons – Event-by-event fluctuations – Two particle correlations (YN, YY correlations in high baryon density) – flow (related to EOS?) – Di-leptons (di-electron and di-muon) Vector meson mass spectra Hadron Physics – Hypernuclei – Exotic hadrons  (1405) Dibaryon (H-dibaryon,  N, ,…) Kaonic nucleus (K - pp,…) – Charm J/ , D, charmed baryons 03/Dec/201515 Onset of QGP Search for critical point Properties of Dense matter K. Ozawa 20AGeV case

16. Beam Energy Consideration 03/Dec/2015K. Ozawa16

17. High Intensity Beam for rare probes 03/Dec/2015K. Ozawa17 Charm Dilepton Hypernuclei AGS Ref: HSD calculations in FAIR Baseline Technical Report (Mar 2006) A. Andronic, PLB697 (2011) 203 To collect a significant statistics for rare probes, High intensity beam is required. Beam : 10 10 Hz 0.1% target  Interaction rate 10 7 Hz Centrality trigger 1%  DAQ rate = 100kHz In 1 month experiment:   ee 10 7 -10 9 D,J/  10 5- 10 6 (20AGeV) (10 3 -10 4 (10AGeV)) Hypernuclei 10 5 -10 10

18. Experimental challenges 18 03/Dec/2015 K. Ozawa Troidal Magnet Spectrometer

19. Toroidal Beam View RICH Muon Tracker 19 HCAL EMCAL Toroid coils Better B  uniformity With larger number Of coils With 12 coils Variations ~+-20% Coils = insensitive area 03/Dec/2015K. Ozawa

20. 3.2m HCAL EMCAL ZCAL Beam RICH 4m Muon Tracker Toroidal R=1m Top View 20 Toroid 0.25m 0.5m 1.4m 5m 0.65 m 0.66m 0.4m 1.90m 0.9m 0.2m TOF SVD ZCAL Centrality MC + ZCAL Multiplicity counter C 5 F 12 radiator p<3.4GeV/c e-  separation EMCAL (e,  ID) PbWO 4, 15X 0  –  separation p>1.5 GeV/c Fe absorbers + Trackers p<0.8 GeV/c 4m TOF with 30ps p=0.8-1.5GeV/c RICH (Aerogel) HCAL (n  ID) Pb-scintillator, 4  nt 03/Dec/2015K. Ozawa GEM trackers

21. Spectrometer performance Acceptance >= 78 %  /K separation 2.5GeV/c (2.5  ) Assuming TOF resolution of 50 ps 21 Forward trackers Acceptance = 77.5% Acceptance = 64.2% Acceptance = 95.0%  p/p p(GeV/c) U+U at 10AGeV/c with JAM + GEANT4 Assumption for simplicity – Half-spherical toroidal shape – Uniform B  field – Dead area due to coils is not implemented H. Sako, B.C. Kim ++ p y y m 2 (GeV/c 2 ) p/Z (GeV/c) 03/Dec/2015K. Ozawa

22. Simulated di-electron spectrum (preliminary) 22 Based on  0 spectra of JAM Other hadrons m T -scaled b<1fm (0.25% centrality) Momentum resolution 2% Electron efficiency 50% (No detector response) 10 11 events ⇔ 100k events/s x 1 month running  isolation = rejection efficiency of close opening angle Dalitz pair Calculations by T. Gunji and T. Sakaguchi     03/Dec/2015 Solenoid+Dipole setup K. Ozawa

23. Summary New beam line is under construction. The beam line will provide following beams – Primary Proton for pA experiment – Secondary produced beam for  A experiment – Heavy Ion Beam for AA experiment Exclusive measurements of vector meson mass spectra is planned using a secondary beam. Future Heavy ion program at J-PARC is under discussion. We should think about High Intensity Beam for Rare probes and Beam Energy upgrade 03/Dec/201523K. Ozawa

24. Back up 03/Dec/2015K. Ozawa24

25. Key components High resolution of the beam momentum measurements using a dispersive focal plane method.  p/p ~ 0.12% 03/Dec/2015K. Ozawa25 Small extraction angle to maximize a beam intensity. Spectrometer

26. Production target & extraction 03/Dec/2015K. Ozawa26 Using beam swingers, extraction angle of 0 degree can be achieved.

27. Secondary beam intensity 03/Dec/2015K. Ozawa27

28. Reaction and Beam momentum 03/Dec/2015 K. Ozawa 28 Stopped  meson       n   A   + n+X  00 As a result of KEK-E325, 9% mass decreasing (70 MeV/c 2 ) can be expected. To generate stopped modified  meson, beam momentum is ~ 1.8 GeV/c. (K1.8 will be used.) Focus on p  < 100 MeV/c Generate  meson using   + p. - Decay of  meson is detected. - Emitted neutron is detected at 0. If  momentum is chosen carefully, momentum transfer will be ~ 0.  momentum [GeV/c] 0.2 0.4 0 2 4  momentum [GeV/c] 0

29. HCAL ZCAL Beam RICH 4m Muon Tracker R=1m Side View 29 Toroidal coil 1.3m 0.5m 5m 0.66m 0.4m 1.90m 6.36m 0.2m 4.15m B=2T gap=0.65 BL=1.3Tm Forward trackers Troidal trackers Barrel trackers 0.65m EMCAL 03/Dec/2015K. Ozawa

30. Heavy-ion programs in the world 30 AcceleratorTypeBeam energy (AGeV) C.M. energy √s(AGeV) Beam rate / Luminosity Interaction rate (sec -1 ) Years of experiments RHIC Beam Energy Scan (BNL) Collider7.7-6210 26 -10 27 cm -2 s -1 (√s=20AGeV) 600~6000 (√s=20AGeV) 2004-2010 2018-2019 (e-cooling) NICA (JINR) Collider Fixed target 0.6-4.54-11 1.9-2.4 10 27 cm -2 s -1 (√s=9AGeV Au+Au) ~60002019- 2017- FAIR SIS100 (CBM) Fixed target 2-11(Au)2-4.71.5x10 10 cycle -1 (10s cycle,U 92+ ) 10 5 -10 7 (detector) 2021- J-PARCFixed target 1-19(U)1.9-6.210 10 -10 11 cycle -1 (~6s cycle) 10 7 -10 8 ? (0.1% target) ? References RHIC: A. Fedotov, LEReC Review, 2013 FAIR: FAIR Baseline Technical Review, C. Strum, INPC2013, Firenze, Italy; S. Seddik, FAIRNESS-2013, C. Hoehne, CPOD2014 NICA : A. Kovalenko, Joint US-CERN-Japan-Russia Accelerator School, Shizuoka, Japan, 2013, A. Sorin, CPOD2014 03/Dec/2015 K. Ozawa