Experimental Progress in Strangeness Nuclear Physics — Report from Group A01&A02 — T.Takahashi on behalf of Group A01 & A02 (KEK IPNS/J ‐ PARC Center) at NSMAT2016 (2016 Nov. 21)
Contents • Introduction • Goal of Group ‐ A projects • Knowledge on Hyperon Potential & Interaction in 2012 • Experimental Progress in SNP • Progress – 5 physics results • Detectors under construction • Hyperon Spectrometer & CATCH • Summary 2016/11/21 NSMAT2016 2
Introduction 2016/11/21 NSMAT2016 3
Joint project between experiments, observations, theories “ Science of Matter based World-best Ｘ -ray observatory on quarks ” two accelerators and ASTRO-H X-ray satellite Understand structure of n-star Theories Unstable beam factory RIBF Nuclear matter EOS r X-ray astronomy ⇒ n-star radius n-rich nuclei High Int. proto acc. Cold atoms J-PARC ⇒ properties of neutron matter Strangeness nuclear ⇒ Interaction of hyperons physics 2016/11/21 NSMAT2016 4
A01: Interactions of multi ‐ strangeness systems Determine hyperon mixing in the inner core （ > 3 0 ） → EOS of high density matter Baryon fraction H dibaryon ？ co fraction correl elat ation (Unique in the world) Hyperon spectrometer ? E42 （ density ） int. N → int. n N int. TPC, S.C.magnet nuclei from emulsion Sato, Imai, hypernuclear spetrocopy Takahashi, (Unique in the world, 10 times improved) (Unique in the world) Naruki E05 E07 π - Takahashi, Naruki p 6 He Λ Λ 4 He Nakazawa 、 Sumihama 10 5 t H.takahashi He Λ Ξ - 5 0 0 5 10μ m Peak in invariant mass 6 Expected 12 He hypernucleus C spectrum 2016/11/21 NSMAT2016 5
A02: Strangeness in n-rich matter Sattered proton detector Determine hyperon mixing in =2~3 0 p region where hyperons begin to appear Ultra-fast (x100) Fiber tr Tracking detector Using MPPC LH2 targ 1) + p s ( 1) Ca p scattering （ unique ） Mi Miwa, Ta Tamura ‐ > n ( p) E40 coherent coupling p) in int. t. p/n PiID co n n => exists in n ‐ star or not => Forward calorimeter (2a) spectroscopy of (2a) ? E13 n n fraction n attractive hypernuclei pernuclei (Unique method ) Ko Koike, Ta Tamura p of N, N, NN ‐ > Det Details ils of NN in int. E10 n (2b) (2b) n ‐ rich rich hypernuclei pernuclei (Unique method) Sak Sakagu guch chi, i, Aj Ajim imur ura, a, Fuk Fukuda uda ‐ > nn n repulsive nn int. t. in in n ‐ rich rich en envir vironmen ent of in n ‐ star => Fr => Fractio tion of (3) K ‐ nuclear (3) nuclear bound bound state states Outa,, Suzuki ‐ > K bar bar N in int. t. in in mat matter E15, E27 p p => => K co condensation in in n sta star? ρ K - 2016/11/21 NSMAT2016 6
Hyperon Potential & Interactions knowledge in 2012 (at Kick-off sympo.) : U = 30 MeV in normal (N Z) matter at 0 Group ‐ A02 U ? in neutron ‐ rich matter (S= 1) ( , , ) : N int. is repulsive but how much? ( , ) : nucleus is not well established U = 14 MeV ? ( 12 Be) to be established B = 2.6 MeV ? ( + 14 N twin ‐ nucleus) interaction: Group ‐ A01 (S= 2) B = 0.67 ± 0.17 MeV from NAGARA event systematic data (A ‐ dependence) YY: N: 2016/11/21 NSMAT2016 7
Progress of SNP (2012 - present) 2016/11/21 NSMAT2016 8
Progress (1) Discovery of Ξ nucleus ⇒ K.Nakazawa In the R&D of E07 Discovery of ‐ Nucleus for the first time – KISO Event – In the test application of Overall Scanning Method, which is under R&D for In the test application of Overall Scanning Method, which is under R&D for incoming E07 Experiment, to the emulsion sample irradiated before, we found the incoming E07 Experiment, to the emulsion sample irradiated before, we found the event in which is deeply bound in 14 N. This is the first evidence of ‐ nucleus event in which is deeply bound in 14 N. This is the first evidence of ‐ nucleus PTEP 033D02 (2015) + 14 N → 10 Be(#1) + 5 He(#2) Newspaper （ 2015/1/19 ） Binding energy of > 1.03 ± 0.18 MeV c.f. 0.17 MeV （ atomic orbit ） 3.87 ± 0.21 MeV if 10 Be is in ground state. Attractive N interaction has been established. In E07, ~100 double ‐ strangeness events will be observed. ⇒ detailed information on S= ‐ 2 interaction 2016/11/21 NSMAT2016 9
Start of E07 (Emulsion exp.) at K1.8 KURAMA ( 260msr) installed at K1.8 momentum [GeV/c] K K Beam was exposed to the 18/118 emulsion stacks in June 2016. ⇒ K.Nakazawa ⇒ S.Hayakawa & M.Fujita (poster) 2016/11/21 NSMAT2016 10
Progress (2): 12 C(K - ,K + ) Pilot data - - + + Missing mass p(K Missing mass p(K , K , K ) at 1.8 GeV/c ) at 1.8 GeV/c (K ,K + ) Missing mass spectroscopy using SKS Counts /0.5 MeV 500 M 6 MeV (FWHM) 400 300 200 previous data at BNL ‐ AGS 100 M 14 MeV(FWHM) 0 1.3 1.3051.311.3151.321.3251.331.3351.341.3451.35 Missing Mass (GeV) ⇒ S.Kanatsuki P.Khaustov et al., PRC61 (2000)054603 2016/11/21 NSMAT2016 11
Progress (3): Neutron-rich Λ nuclei — No observation of 6 Λ H (J-PARCE10) — H.Sugimura et al. PLB729(2014)39 6 Li ( , K + ) X 5 H + t + 2n + Glue like 0.0 role of FINUDA 4 H + 2n ‐ 2.04 ‐ 2.31 coherent No peak structure coupling 6 H in bound/resonance region U.L. 1.2nb/sr (90%C.L.) Y.Akaishi et al. Phys.Rev.Lett.84(2000)3539 ⇒ R.Honda M.Agnello et al., FINUDA Collaboration PRL 108 (2012) 042501 2016/11/21 NSMAT2016 12
Progress (4) Charge Symmetry Breaking in ΛN interaction ‐ ray spectroscopy at J ‐ PARC E13 2015 Apr. ‐ May 4 He(K , ) June counts/8 keV 2016/11/21 NSMAT2016 13 E [MeV]
Progress (4) Charge Symmetry Breaking in ΛN interaction T.O.Yamamoto et al. PRL115 (2015) 22501 • Large CSB of 1 + ‐ 0 + level spacing • spin ‐ dependent CSB • 1 + : small/no • 0 + : large • effect of N ‐ N mixing ? Importance of Three ‐ Body Force ⇒ T.O.Yamamoto & S.Nagao decay spectroscopy at MANI ‐ C 2.12 ± 0.01 stat. ± 0.09 syst. ⇒ S.Yang , M.Nakagawa ( other E13 results ) A.Esser et al. PRL114(2015)232501 2016/11/21 NSMAT2016 14
Progress (5) Observation of “K - pp” Y.Ichikawa et al. PTEP 2015 21D01 J ‐ PARC E27 @K1.8 1405) doorway production at p =1.69 GeV/c d → K + X X → p → p → p p +18 +30 B = 95 (stat.) (syst.) MeV 17 21 = 162 (stat.) (syst.) MeV +66 +87 78 45 Mx 2016/11/21 NSMAT2016 15
Progress (5) Observation of “K - pp” J ‐ PARC E15 @K1.8BR K 3 He → X n at p K = 1.0 GeV/c X → p E15 2nd Y.Sada et al. PTEP (2016) 051D01 2015 Nov. ‐ Dec. E15 1st 2013 May M[K+p+p] M[ + +N] Two structures around M[K+p+p]!? ⇒ H.Outa 2016/11/21 NSMAT2016 16
Large-Acceptance Hyperon Spectrometer for H-dibaryon Search (E42) K C (diamond) → K + H X Hyperon Spectrometer H → / p / p K1.8BS → p KURAMA Hyperon Spectrometer (HS) S.C. Helmholtz magnet 1.0 T • large acceptance TPC with 3 GEM layers • high ‐ rate tolerance GET readout system (K ) beam 1MHz TOF hodoscopes • good invariant mass .... resolution 1MeV Target inside TPC ⇒ J.K.Ahn S.H.Kim (poster) 2016/11/21 NSMAT2016 17
Hyperon Spectrometer - S.C. Helmholtz magnet - Max field: 1.5 T @ 99.9A Field region: 500mm φ × 500mm Weight: 10 ton Conductive cooling by 2 GM cryocoolers KEK ‐ Tsukuba Campus (ERL building) All of necessary items (cryocoolers, monitors, power supply etc.) will be ready mid ‐ Dec. Then we will start cooling / excitation tests. 2016/11/21 NSMAT2016 18
Hyperon Spectrometer - TPC - Full set of TPC was fabricated and arrived at J ‐ PARC (Oct.2016) The first cosmic ‐ ray event Beam test at ELPH ‐ Tohoku, Nov.7 ‐ 10 ⇒ S.H.Kim (poster) 2016/11/21 NSMAT2016 19
CATCH for Σp Scattering Exp. ⇒ K.Miwa p = n interaction ( ) ( ) Liq.H 2 Requirements Cylindrical Fiber Tracker (CFT) • Large acceptance for scattered proton 4 layers for & 4 layers for UV • High rate tolerance MPPC readout beam rate 10MHz • Kinematical identification of p scattering BGO calorimeter energy and direction shaping amplifier + flash ADC readout 2016/11/21 NSMAT2016 20
CATCH and its first application Construction of CATCH was just completed. Cylindrical Fiber Tracker (CFT) BGO calorimeter 1 st application to physics experiment p ‐ d elastic scattering and break ‐ up reaction experiment using CATCH will be performed at CYRIC ‐ Tohoku Jan.16 ‐ 17, 2017 ⇒ Y.Akazawa
Beam power & K - intensity (K1.8BL) @38.6kW ( Nov. 2014 ) duration: 5.51 sec. spill length: 2.0 ‐ 2.1 sec. 4.43 × 10 13 ppp (optimal condition) 24kW 33kW 38.6kW • Design of 80kW (Apr.2014) (June 2014) (Nov. 2014) target was finished 53 kw x (s. f.) • R & D of >100kW (42kW) 41.5kW (next) (June 2015) target is underway (Dec. 2014) limited by T1 2016/11/21 NSMAT2016 22
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