J-PARC (Japan Proton Accelerator Research Complex)

Transcription

1

2 J-PARC Tokai, Japan (Japan Proton Accelerator Research Complex) Material and Biological Science Facility 50 GeV Synchrotron (15 ma) 400 MeV Linac (350m) 3 GeV Synchrotron (333 ma) Neutrino Facility World-highest beam intensity : ~1 MW x10 of BNL-AGS, x100 of KEK-PS

3 Korean Users Community Users in various fields Condensed matter, high-energy, nuclear/hadron and accelerator Very active and productive with strong international collaborations. There are already over 200 potential users of J-PARC in Korea Korea is the nearest country Very favorable for Korea A long history of strong collaborations between Korea and Japan since 1984 J-PARC is a very useful research facility for the future developments of Korean physics communities.

4 Support of Korean J-PARC users is essential Center for Korean J-PARC Users (CKorJ-PARC) Established in May 2010 CKorJ-PARC Strong support from Korean government

5 Organization Participating groups: 22 Universities, National Labs. & Industry

6

7

8

9 Nuclear & Hadron Physics in J-PARC

10 approved / proposed (incl. LOI) 30~50 GeV primary beam J-PARC Hadron Hall Strangeness nuclear physics at K1.8BR and K1.8 K - nucleus bound states K - Handron atomic X rays Hall h nucleus f nucleus Hyperon resonances K1.8BR Production target (T1) g spectroscopy of L hypernuclei n-rich L hypernuclei X hypernuclei LL hypernuclei X-atomic X rays Q + search Beam Dump Weak decays of L hypernuclei K1.8 K - nucleus bound states Pion double charge exchange nucleus High Mom. YN scattering Line Hadron mass in nuclei Nucleon quark structure KL meson structure K1.1 Q + study g spectroscopy K1.1BR of L hyp. S hypernuclei Q + hypernuclei

11 June, 2007

12 June, 2007

13 Dec, 2008

14 K1.8 beamline Apr, 2010

15 Nuclei with strangeness Nuclei: many body systems of nucleons which consist of up and down quarks p(uud), n(udd) Actually, there are 6 kinds (flavors) of quarks u c t d s b Baryons with strangeness = Hyperons L=(uds), S + (uus), X 0 =(uss),... Extended space of nuclei

16 Hyper-nuclear chart Unexplored space S=0 surface

17 A Z LZL Notation A: Baryon number Z: Total charge (not proton number!) L: Hyperon(L, S, X, etc) Some examples: 1. 3p + 3n + 1L 7 LLi 2. 2p + 2n + 2L 6 LLHe 3. 1p + 2n + 1X 0 2p + 1n + 1X - Often called as hypernuclei 4 XH (Indistinguishable)

18 Physics New interaction (also talk by H. Nemura tomorrow afternoon) Extended nuclear force to 3-flavor world Unified understanding of Baryon-Baryon force What is its origin? Is traditional meson exchange model enough? Need quark/gluon picture? Property of hyperons in nuclei? Hyperons can mix easily (e.g., LN-SN, LL-XN) Dynamical systems can be made What happens to nuclei? Impurity effect? Collective motion? High density matter? Relation with neutron stars

19 Present status of Hadron Hall Construction is over. Started physics runs concurrent with engineering runs. Beam intensity: only a few % of the design, but rapidly increasing The first physics data was successfully taken in Nov (for E19) Pentaquark search Preliminary result is already obtained!

20

21

22 Korean Contributions Leading two approved experiments E03: X-ray measurement from X atom K. Tanida (Seoul National University) E18: non-mesonic weak decay of Λ-hypernuclei H. C. Bhang (Seoul National University) Also contributing many other experiments Construction of detectors Further contribution expected Letters-of-Intent and ideas for future experiments New beamline? Spectrometer?

23 E03 experiment World first measurement of X rays from X-atom Gives direct information on the XA optical potential Produce X - by the Fe(K -,K + ) reaction, make it stop in the target, and measure X rays. Aiming at establishing the experimental method X - (dss) Fe target K - K + X - Fe X ray X ray

24 Physics Motivation Strangeness nuclear physics at S=-2 A doorway to the multistrangeness system Neutron star Very dynamic system? Large baryon mixing? Inversely proportional to mass difference. H dibaryon as a mixed state of LL-XN-SS? Little is known so far Unique at J-PARC

25 Energy (arbitrary scale) X atom level scheme... l=n-3 l=n-2 l=n-1 (circular state) X... Z... nuclear absorption X... Z l (orbital angular momentum) X ray energy shift real part Width, yield imaginary part Successfully used for p -, K -,`p, and S -

26 X(g)-ray detector Hyperball-J germanium detector array Collaborating with Tohoku University (talk by T. Koike this afternoon & poster by S.-B. Yang)

27 E18 weak decay of hypernuclei Decay of L-hypernuclei by weak interaction L in free space: L Np (mesonic weak decay) suppressed in nuclei, due to Pauli effect In nuclei, non-mesonic weak decay occurs LN nn Mechanism? Naïve: L Np, which is absorbed by another N Fails to explain experimental data New process: LNN nnn?

28 Setup Detect all particles from weak decay 2 or 3 body decay?

29 Korea-Japan Meeting The first Korea-Japan Meeting on Nuclear and Particle Physics at J-PARC Hadron Hall was held on Nov , 2010 Participants: 21 from Korea & 23 from Japan Including a few Japanese working for Korean institutes (and vise versa) Hot discussion Present status Ideas for future experiments Korean beamline?

30

31

32 Summary Researches in various fields are planned/ongoing at J-PARC Korea is actively contributing in all areas CKorJ-PARC is established to support Korean J-PARC users Nuclear and Hadron physics Physics runs just started Korean institutes are leading two experiments Korea-Japan meeting was held in Nov Hot discussion on future experiments and Korean contributions Strong collaboration between Korea & Japan already yielding results. Even stronger in the future!