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J-PARC Heavy ion program and related topics K. Ozawa (KEK) ECT* 10000km Tokyo 03/Dec/2015 K. Ozawa 2 150km J-PARC KEK Tsukuba Univ. Narita Tokyo 03/Dec/2015 K. Ozawa 3 J-PARC Tokai, Japan (Japan Proton Accelerator Research Complex) Material and Life Science Facility 400 MeV Linac RCS 3 GeV Synchrotron MR 30 GeV Synchrotron Hadron Experimental FacilityHall Hadron 60m x 56m Neutrino Experimental Facility 03/Dec/2015 K. Ozawa 4 30 GeV Accelerator & Hadron Experimental Facility Hadron Experimental Facility Transfer Line from Acc. to Hadron North Side New Beamline (under construction) Current Production target for secondary beams Branch Point from Acc. to Hadron 03/Dec/2015 K. Ozawa South Side 5 Hadron Experimental Facility K1.8 K1.8BR Production Target K1.1 KL High-p COMET Name K1.8 K1.8BR K1.1 High-p 03/Dec/2015 Species p±, K± p±, K± p±, K± proton Unseparated Energy < 2.0 GeV/c < 1.0 GeV/c < 1.1 GeV/c 30GeV < 20GeV/c K. Ozawa Intensity ~105 Hz for K+ ~ 104 Hz for K+ ~ 104 Hz for K+ ~ 1010 Hz ~ 108 Hz Under Construction 6 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), 1010 per spill High Momentum un-separated secondary beam (< 20GeV/c), 108 per spill Primary Proton Beam (8GeV) for COMET The new beam line will be operated in 2017. New Beam Line Physics Vector mesons in nucleus Charmed Baryon and hadron structure mu-e conversion (COMET) 03/Dec/2015 K. Ozawa 7 New Beam Line – Physics Program Primary Proton Beam pA reaction Vector meson spectra via Dielectron measurements* Secondary Beam pA reaction Exclusive measurements Resonance Study Heavy Ion Beam AA reaction Vector meson in high density matter Charmed Baryon * Details will be presented by K. Aoki on Friday 03/Dec/2015 K. Ozawa 8 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 p mesons • K mesons and protons are also contained • Physics • Di-lepton measurements • Charmed baryon spectroscopy 03/Dec/2015 K. Ozawa 9 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. p+A r/ + p+X p p r/ e+e- e+ Elementary Reaction: ep+ + n (in A) r/ + p We can measure p (beam), r/ (decays), emitted proton (Forward spectrometer) The reaction dynamics can be identified by these measurements. 03/Dec/2015 K. Ozawa 10 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. • Elementary reaction • p+ + n (in A) r/ + p • Forward emitted proton carries momentum of incident beam and generated w meson has small momentum • We can measure mass spectra in nucleus at “p0”. 03/Dec/2015 K. Ozawa 11 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 r mass region • In addition, relatively high momentum p beam can probe a structure of N* • r/ interference and mass modification Nucl. Phys, A713(2003), 97 • M.F.M. Lutz, B. Friman, M. Soyeur calculated effects of r/w interference on di-lepton mass spectra 03/Dec/2015 K. Ozawa 12 J-PARC HI Project Acceleration Scheme for Uranium case(Proposed by H. Harada, J-PARC) U35+→U55+ 20.0→19.86 MeV/u U66+→U86+ 67.0→62.34 MeV/u stripping stripping HI LINAC HI booster U86+→U92+ 735.21→727.0 MeV/u stripping RCS MR U86+ 62.34→735.21 MeV/u U92+ 727.0Mev/u→11.15 GeV/u (30GeV@p) stripping U35+ 20.0MeV/u U55+→U66+ 19.86→67.0 MeV/u New LINAC and Booster for HI must be constructed. 03/Dec/2015 K. Ozawa 13 J-PARC Heavy Ion specification “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 pmA – 10ms, 25Hz 03/Dec/2015 “High Enegy” Program (30 GeV MR) • Ion species • p, Si, Ar, Cu, Xe, Au(Pb), U • Also light ions for hypernuclei • Maximum baryon density in U+U • Beam energy • 1 - 11 AGeV(U, 𝑠𝑁𝑁 = 2−4.9GeV) • 19 AGeV(U, 𝑠𝑁𝑁 = 6.2GeV) for 50GeV • Rate • 1010-1011 ions per cycle (~a few sec) K. Ozawa 14 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 Onset of QGP Search for critical point r/r0 Properties of Dense matter Calculated by JAM model, Y. Nara, Phys. Rev. C61,024901(1999) • Hadron Physics 20AGeV case – Hypernuclei – Exotic hadrons • L(1405) • Dibaryon (H-dibaryon, WN, DD,…) • Kaonic nucleus (K-pp,…) – Charm • J/y, D, charmed baryons 03/Dec/2015 K. Ozawa 15 Beam Energy Consideration • Currently, main ring of J-PARC has a beam energy of 30GeV for a proton acceleration. • It is the same as SIS100/FAIR. • For HI, 11AGeV, 𝑠𝑁𝑁 = 4.9GeV • Original designed energy of the ring is 50GeV for proton • For HI, 19AGeV, 𝑠𝑁𝑁 = 6.2GeV • Original designed energy should be recovered • Highest density expected at 𝑠𝑁𝑁 = 8GeV • Randrup, PRC74(2006)047901 • Significant increasing of charm production cross section • Seamless connection to SPS/RHIC BES • New power supply is required 03/Dec/2015 K. Ozawa 16 High Intensity Beam for rare probes Ref: HSD calculations in FAIR Baseline Technical Report (Mar 2006) A. Andronic, PLB697 (2011) 203 AGS Hypernuclei Dilepton To collect a significant statistics for rare probes, High intensity beam is required. Beam : 1010 Hz 0.1% target Interaction rate 107 Hz Centrality trigger 1% DAQ rate = 100kHz Charm In 1 month experiment: r,,fee 107-109 D,J/Y 105-106 (20AGeV) (103 -104(10AGeV)) Hypernuclei 105 -1010 03/Dec/2015 K. Ozawa 17 Experimental challenges • High rate capability – Fast detectors • Silicon trackers, GEM trackers, … – Extremely fast DAQ trigger-less DAQ • >= 100kHz • High granularity – Pixel size < 3x3mm2 (at 1m from the target, q<2deg, 10% occupancy) • Large acceptance (~4p) – Coverage for low beam energies • Up to 𝑠𝑁𝑁 = 6.2GeV, even for 19AGeV beam – Maximum multiplicity for e-b-e fluctuations – Backward physics (target fragment region) Troidal Magnet Spectrometer • Electron measurement – Field free region for RICH close to the target 03/Dec/2015 K. Ozawa 18 Muon Tracker HCAL Beam View EMCAL Toroidal RICH Coils = insensitive area Better Bf uniformity With larger number Of coils With 12 coils Variations ~+-20% Toroid coils 03/Dec/2015 K. Ozawa 19 0.9m 3.2m Muon Tracker Top EMCAL (e,g ID)View HCAL EMCAL 1.90m HCAL (n ID) Toroid Pb-scintillator, 4lint TOF PbWO4, 15X0 Toroidal e-p separation 0.5m SVD RICH R=1m C5F12 radiator p<3.4GeV/c 0.25m Multiplicity counter 5m m–p separation Beam p>1.5 GeV/c Fe absorbers + 4m Trackers p<0.8 GeV/c 4m TOF with 30ps p=0.8-1.5GeV/c RICH (Aerogel) 0.66m 0.4m ZCAL 0.2m ZCAL 1.4m GEM trackers Centrality MC + ZCAL 03/Dec/2015 K. Ozawa 20 Spectrometer performance U+U at 10AGeV/c with JAM + GEANT4 • p/Z (GeV/c) H. Sako, B.C. Kim Assumption for simplicity – Half-spherical toroidal shape – Uniform Bf field – Dead area due to coils is not implemented • Acceptance >= 78 % • p/K separation 2.5GeV/c (2.5s) Assuming TOF resolution of 50 ps Forward trackers 03/Dec/2015 p+ Acceptance = 77.5% m2 (GeV/c2) K. Ozawa y p Acceptance = 95.0% y 21 Simulated di-electron spectrum (preliminary) Based on p0 spectra of JAM Other hadrons mT-scaled p0 b<1fm (0.25% centrality) r f Momentum resolution 2% Electron efficiency 50% (No detector response) 1011 events ⇔100k events/s x 1 month running eisolation = rejection efficiency of close opening angle Dalitz pair Calculations by T. Gunji and T. Sakaguchi 03/Dec/2015 K. Ozawa Solenoid+Dipole setup 22 Summary • New beam line is under construction. The beam line will provide following beams – Primary Proton for pA experiment – Secondary produced beam for pA 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/2015 K. Ozawa 23 Back up 03/Dec/2015 K. Ozawa 24 Key components • High resolution of the beam momentum measurements using a dispersive focal plane method. • Dp/p ~ 0.12% Spectrometer • Small extraction angle to maximize a beam intensity. 03/Dec/2015 K. Ozawa 25 Production target & extraction Using beam swingers, extraction angle of 0 degree can be achieved. 03/Dec/2015 K. Ozawa 26 Secondary beam intensity 03/Dec/2015 K. Ozawa 27 Reaction and Beam momentum n g m g Generate meson using p- + p. - Decay of meson is detected. p A + n+X - Emitted neutron is detected at 0. p0 g p p + p g 2 p0g gg As a result of KEK-E325, 9% mass decreasing (70 MeV/c2) 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 03/Dec/2015 If p momentum is chosen carefully, momentum transfer will be ~ 0. momentum [GeV/c] p Stopped meson K. Ozawa 0.4 0.2 0 0 2 p momentum [GeV/c] 4 28 1.3m Muon Tracker Side View HCAL EMCAL 1.90m Barrel trackers RICH 0.66m 0.4m Toroidal coil 5m Beam 0.2m ZCAL 4m Forward trackers B=2T gap=0.65 BL=1.3Tm 03/Dec/2015 Troidal trackers 4.15m K. Ozawa 6.36m 29 Heavy-ion programs in the world Accelerator Type Beam energy (AGeV) C.M. Beam rate / energy Luminosity √s(AGeV) RHIC Beam Collider Energy Scan (BNL) 7.7-62 NICA (JINR) 4-11 Collider 0.6-4.5 Interaction rate (sec-1) Years of experiments 1026-1027cm-2s-1 600~6000 (√s=20AGeV) (√s=20AGeV) 2004-2010 2018-2019 (e-cooling) 1027 cm-2s-1 ~6000 2019- (√s=9AGeV Au+Au) Fixed target 1.9-2.4 FAIR SIS100 (CBM) Fixed target 2-11(Au) 2-4.7 J-PARC Fixed target 1-19(U) 20171.5x1010 cycle-1 (10s 1.9-6.2 cycle,U92+) 1010-1011 cycle-1 (~6s cycle) 105-107 (detector) 2021- 107-108 ? ? (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 30 K. Ozawa 03/Dec/2015