Overview of Hypernuclear Physics Program at K1.8 and K1.1 Beam lines of J- PARC

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1 Overview of Hypernuclear Physics Program at K1.8 and K1.1 Beam lines of J- PARC T.Takahashi (IPNS- KEK) 1

2 Contents Recent achievements on Hadron Facility Experimental plan by the next summer ( ) Facility upgrade and experimental plan aler 2014 K1.1 Beam line & SKS High- p/comet E13/E18/E07/E05 New approved proposals Hadron hall extension plan Summary 2

3 Recent Achievements on Beam & Nuclear Physics Program before (Nov.-Dec. 2010, RUN36) K1.8/K1.8BR/KL/K1.1BR MR power 3.0kW, D.F.= 17% Dec.9 LINAC opera`on started Dec.24 MR beam to Neutrino 2012 Jan.28-Feb.22 (RUN40) K1.8/K1.8BR/KL 3.3kW, D.F.= 30% 2012 Jun.9-Jul.1 (RUN43) K1.8/K1.8BR/KL/K1.1BR 6.6kW, D.F.= 30% E19 1 st RUN@K1.8 Beam tuning K1.8BR Beam survey KL E19 2 nd RUN@K1.8 Beam & detector (CDS) Detector study & commissioning@kl E27 pilot RUN@K1.8 Detector Detector study & commissioning@kl 3

4 E19: Search for Θ + via the p(π -,K - )X M.Moritsu in Parallel 2 on Oct.1 1 st RUN at 1.92 GeV/c 2 nd RUN at 2.0 GeV/c Max. momentum at K1.8 B.L. Extend mom. acceptance from 1 st RUN Same spectrometer s performance as before the Earthquake BG No peak structure was observed. U.L. : 0.26µb/sr U.L. of width 0.72MeV/c 2 for ½ MeV/c 2 for ½ - K.Shirotori et al. PRL 109, (2012). 4

5 E27: Search for K - pp bound state via the d(π +,K + ) reac[on K - pp is produced via Λ(1405) doorway in the d(π +,K + ) at 1.7GeV/c d π + Λ* K + n p K - pp Missing mass by Beam & SKS spectrometers Two protons are detected by RCA in order to suppress quasi- free B.G. Y.Ichikawa Poster, H.Ekawa Poster π + + n Λ * + K + Λ * + p bound K - pp Minor quasi- free Λ * Dominant Y.Akaishi, T.Yamazaki, Phys. Rev. C (2007) Σ +,Σ 0 inclusive spectrum Simula5on K + Λ Acceptance p p Λ *,Σ * 5 π +

6 E27 Pilot Run in June 2012 Y.Ichikawa Poster, H.Ekawa Poster Goal & Beam Summary The first measurement on inclusive d(π +,K + )X spectrum at this incident momentum (1.7GeV/c) and missing mass region ( GeV/c 2 ) Ø 7.6days, π + on Liq.D 2 (1.7g/cm 2 ) Measurement on p(π +,K + )X spectrum to check p contribu`on in d. Ø 0.6days, π + on Liq.H 2 (0.86g/cm 2 ) Check feasibility of proton coincidence [counts] Σ + p(π +,K + ) Very Preliminary [counts] Λ Σ d(π +,K + ) Inclusive Black: Simula`on Red: Data Very Preliminary Y* Σ *+ 6 Missing mass [GeV/c 2 ] Missing mass [GeV/c 2 ]

7 Experimental plan by the next summer 7

8) 150k/spill @10kW K1.8 & SKS K1.8BR & CDS, ntof K1.

8 Hadron Hall in 2012 and 2013 K1.8BR pmax=1.0gev/c K-(1.0) K1.8 pmax=2.0gev/c K-(1.8) K1.8 & SKS K1.8BR & CDS, ntof K1.1BR pmax=1.0gev/c Test beam line 2012/10/5 KL KL π0ννbar Exp. HYP11 8

9 Hadron Hall in 2012 and 2013 K1.8BR p max =1.0GeV/c K - (1.0) K1.8 p max =2.0GeV/c K - (1.8) SX beam schedule (plan) Dec kW Jan kW Mar kW K1.1BR p max =1.0GeV/c Test beam line KL K L π 0 νν bar Exp. May 15 Jun >20kW (+E05-1,... ) Aug long shutdown for LINAC 400MeV U.G. MR opera5on starts from Feb

Neutron halo structure of 8 He may disappear by adding a Λ.

10 E10: Produc[on of Neutron- Rich Λ Hypernuclei, 6 Λ H and 9 Λ He, via the DCX (π-,k + ) Reac[on Ø Change of proper`es on nuclei near neutron drip- line Unbound 5 H will be bound by adding a Λ. Neutron halo structure of 8 He may disappear by adding a Λ. Ø ΛN interac`on in the extreme condi`on ΛN- ΣN mixing effect EOS of neutron star mawer K.S.Myint and Y.Akaishi, Prog. Theor. Phys. Suppl. 146, 599 (2002) 10

E10-1: 6 Li(π -,K + ) 6 Λ H Data from FINUDA/DAΦNE 6 Li(stopped- K -,π + ) reac`on 3 candidate events 5802.33 (5801.41) 5803.45 (5802.73) 5799.97 (5798.

cycle) Target thickness ( 6 Li) DCX cross sec`on (assumed) Values 1.2 GeV/c 10M/spill 3T pions 3.5 g/cm 2 10 nb/sr Es`mated 6 ΛH yield 265 M.Agnello et al.

11 E10-1: 6 Li(π -,K + ) 6 Λ H Data from FINUDA/DAΦNE 6 Li(stopped- K -,π + ) reac`on 3 candidate events ( ) ( ) ( ) Dec.,2012 ー Jan., Beam line Parameters Pion beam momentum Pion beam intensity Total number of pions (6 s acc. cycle) Target thickness ( 6 Li) DCX cross sec`on (assumed) Values 1.2 GeV/c 10M/spill 3T pions 3.5 g/cm 2 10 nb/sr Es`mated 6 ΛH yield 265 M.Agnello et al. PRL 108,042501(2012) E.BoFa Oct.3(Wed) Simulation 10M/spill is very challenging. ( 5M/spill is sure.) 3 weeks data- taking B.Gibson Parallel- 1 on Oct.1 S.Ohnishi Paralel- 1 on Oct.1 11

=20, 1g/cm 3 ) Ø The first sd- shell hypernuclei r- dependence of ΛN interac`on Ø Λ spin- flip B(M1) measurement by DSAM (if enough sta`s`cs)

12 E13-1: γ- ray spectroscopy of 19 Λ F and 4 Λ He Purpose & Goal 19 Λ F using Liq- HF target (B.P.=20, 1g/cm 3 ) Ø The first sd- shell hypernuclei r- dependence of ΛN interac`on Ø Λ spin- flip B(M1) measurement by DSAM (if enough sta`s`cs) g- factor of Λ in nucleus 4 Λ He using Liq- 4 He target Ø CSB 4 Λ H and 4 Λ He level spacing H.Tamura Plenary on Oct.1 M.Ukai Poster, T.Yamamoto Poster Data- taking in May- June, days (+ commissioning) if 20kW is achieved. Hyperball- J was arrived at J- PARC on Aug. 30. Assembling will start aver HYP11. 12

13 Facility upgrage and experimental plan aeer

T1 K1.1 Beam Line & SKS 2014 Feb. ~ IF(H,V) ESS1 ESS2 IF/MS1/MS2 Opening [mm] ±1.5/1.0/1.0 ±3.0/2.0/2.0 Acceptance [msr %] 0.69 1.76 Separators (Wien Filter) 75kV/cm, 2m x 2 K - Intensity @6.

14 T1 K1.1 Beam Line & SKS 2014 Feb. ~ IF(H,V) ESS1 ESS2 IF/MS1/MS2 Opening [mm] ±1.5/1.0/1.0 ±3.0/2.0/2.0 Acceptance [msr %] Separators (Wien Filter) 75kV/cm, 2m x 2 K - (50kW) 1.1 GeV/c 150k 375k 1.0 GeV/c 80k 200k 0.9 GeV/c 33k 90k K/(K+pi+mu) 1.1 GeV/c GeV/c GeV/c Mom- Slit MS1 MS2 Beam Spectrometer FF(28m from T1) SKS 14

High- p/π15 & COMET B.L. KEK is reques5ng to construct new primary beam lines in the south area with the highest priority. In the earliest case, beam lines will be constructed during 2013 2015.

15 High- p/π15 & COMET B.L. KEK is reques5ng to construct new primary beam lines in the south area with the highest priority. In the earliest case, beam lines will be constructed during Experiments at K1.1 can be carried out from Feb to June 2015 before the construc`on. COMET High- p/π15 Experiments at K1.1 and High- p /p15 can be carried out alterna`vely aler the construc`on, by switching the setup annually or bi- annually. 8- GeV primary beam for COMET exp. primary p beam 30GeV secondary (un- separated) beam 15GeV/c 15

16 3 Beam lines (K1.8/K1.8BR/K1.1) will be available for Strangeness Physics from 2014 Study on double strangeness system at K1.8 ΛΛ- nuclei, Ξ- nuclei, H dibaryon, X- ray from Ξ atoms (Σ ± p scawering ) Study on S=-1 hypernuclei at K1.1 γ- ray spectroscopy, Σ hypernuclei, Weak decay of Λ hypernuclei 4π detector (CDS) & ntof etc. at K1.8BR K- nuclei, Kaonic atom, Λ(1405),... Ø SX beam `me gradually increases. SX:FX = 1:2 (2012 Oct Jul.) SX:FX = 1:1 or more (2014 ) Y.Sada Parallel- 6, T.Hashimoto Poster, S.Enomoto Parallel- 7 We can carry out a lot of experiments more efficiently at 3 beam lines. 2012/10/5 16 HYP11

17 E13-2: 10 Λ B, 11 Λ B, and 7 Λ Li (K -,π - ) reac5on at 1.1GeV/c >50kW MR power 10 Λ B and 11 Λ B Confirma`on of ΛN spin- dependent interac`on The effect of ΛN- ΣN coupling & 3- body force H.Tamura Plenary on Oct.1 M.Ukai Poster, T.Yamamoto Poster Ν Ν π π Λ Λ Σ + Ν Ν π Λ Λ π Σ Ν Ν 7 Λ Li g- factor of Λ in nucleus spin- flip B(M1) 5% accuracy of B(M1) B(M1)= [µ N 2 ] -g Λ = µ N BNL- E /2 + 5/ Li 7 Λ Li 3/2 + 1/2 + -g Λ (free)=1.226 µ N 17

E18: Coincidence measurement of the weak decay of 12 Λ C H.Outa Parallel 5 on Oct.4 Experimental determina`on of ΛNN NNN weak decay process Recent Exp.

18 E18: Coincidence measurement of the weak decay of 12 Λ C H.Outa Parallel 5 on Oct.4 Experimental determina`on of ΛNN NNN weak decay process Recent Exp./Theory suggests 29±13% of NMWD ( 12 Λ C) Large Acceptance Coverage of Decay Counter (DC) from K1.1 measures efficiently non back- to- back nucleon pair as well as nnn final state to SKS Phase- 1 2M/spill beam with D.F.=30%, 3weeks 0.8T pions on target ( 5T in proposal ) 18

BH2 BAC BC4 3 5 DC1 Magnet KURAMA CH 2 DC2 DC3 0 1 2 [m] K+ TOF Improvements from KEK- E373 1 High purity K - beam

19 BH1 BFT GeV/c K- beam K1.8BS (QQDQQ) Ge Emulsion (D)SSD system 4 BC3 E07: Study on S=-2 system by Emulsion- Counter Hybrid Method BVAC FAC BH2 BAC BC4 3 5 DC1 Magnet KURAMA CH 2 DC2 DC [m] K+ TOF Improvements from KEK- E373 1 High purity K - beam 2 KURAMA gap extension 3 Emulsion 3 4 fiber tracker (D)SSD 16µm resolu`on for Ξ - 5 Posi`on calib. of emulsion layers 20µm 1.4±0.8µm Automa`c scan w/ & w/o counters 6 Ge detectors to measure X- rays from Ξ - - atom Ξ-Nucleus poten`al (in surface region) 10 [mes events as those of the previous exp.! 10 4 Ξ - stopped events 10 2 double- Λ nucl. w/ counters 10 3 double- Λ nucl. w/o counters Commissioning & physics RUN K1.8 19

20 E05: Spectroscopy of Ξ- hypernucleus, 12 Ξ Be First observa`on of Ξ- hypernucleus by the (K -,K + ) missing mass with good resolu`on and high- sta`s`cs. Ξ- Nucleus poten`al (inside nucleus) complimentary to Ξ- Atom Poten`al depth Ξ- N interac`on Width of state(s) Ξ- N ΛΛ interac`on EOS of high- density neutron- star mawer The original proposal using SksPlus spectrometer ΔΩ 30msr ΔM = 3MeV(FWHM) 1.4x10 6 K - /spill beam 30 days s Ξ p Ξ V 0 =-20MeV V 0 =-14MeV difficult to be carried out!! 20

5x10 5 K - /spill (30kW) 100 events/30 days It may have a chance to run in 2013 June, aler E13-1, if MR power increases more rapidly than we

21 E05: 2 step approach phase- 1 with SKS mod minor change from E10-1/E13-1 setup phase- 2 with S- 2S S.Kanatsuki Poster ΔΩ = 110 msr Δp/p = 0.27% ΔM = 4MeV(FWHM) 4.5x10 5 K - /spill (30kW) 100 events/30 days It may have a chance to run in 2013 June, aler E13-1, if MR power increases more rapidly than we expected. Grant- In- Aid for Specially Promoted Research: T.Nagae Q- Q- D spectrometer like HKS at JLab ΔΩ = ~50 msr Δp/p = 0.05% ΔM = 1.5MeV(FWHM) Construc[on completed in 2014 Data- taking 2015? with >150kW MR power K - intensity of 1x10 6 /spill 21

E40: Σ ± p scaqering proposed by K.Miwa, Tohoku Univ. (stage- 1) K.

force. 10 ( 3 S 1 ) of ΣN(I=3/2) channel is almost Pauli- forbidden in the quark- based picture.

high- intensity beam can be used. high- sta`s`cs will be achieved.

22 E40: Σ ± p scaqering proposed by K.Miwa, Tohoku Univ. (stage- 1) K.Miwa Poster ΣN interac`on is strongly related to the origin of the repulsive core of nuclear force. 10 ( 3 S 1 ) of ΣN(I=3/2) channel is almost Pauli- forbidden in the quark- based picture. No use of imaging device. Only counters are used. Scawering event is kinema`cally iden`fied. high- intensity beam can be used. high- sta`s`cs will be achieved. 20M/spill π + beam 90 Σ + /spill events with 20 days 50 cm 30 cm π p Σ Fiber tracker π LH2 target Calorimeter Κ + p/n PiID counter Forward calorimeter 22

E42: Search for H- Dibaryon with a Large Acceptance Hyperon Spectrometer K1.8BL + KURAMA + Hyperon Spectrometer Diamond target K - K + proposed by J.K.Ahn, Pusan Univ.

23 E42: Search for H- Dibaryon with a Large Acceptance Hyperon Spectrometer K1.8BL + KURAMA + Hyperon Spectrometer Diamond target K - K + proposed by J.K.Ahn, Pusan Univ. (stage- 1) Events/2MeV/c 2 Expected H spectra with 30days m H =2250MeV/c 2 (>2m Λ ) TPC + S.C. magnet ΛΛ, Λ pπ - Λpπ - Σ - p, Σ - nπ - Events/5MeV/c ΛΛ invariant mass [GeV/c 2 ] m H =2220MeV/c 2 (<2m Λ ) Λpπ - invariant mass [GeV/c 2 ] 23

Hadron Hall Extension High- resolu`on ( 100keV) spectroscopy of Λ hypernuclei by the (π ±,K + ) reac`ons medium- /heavy- Λ hypernuclei neutron- rich Λ hypernuclei K1.8BR K1.8 K1.

24 Hadron Hall Extension High- resolu`on ( 100keV) spectroscopy of Λ hypernuclei by the (π ±,K + ) reac`ons medium- /heavy- Λ hypernuclei neutron- rich Λ hypernuclei K1.8BR K1.8 K1.1BR T2 HIHR π beam up to 2GeV/c High- intensity 10 9 /spill High- resolu`on Δp/p 10-5 K1.1 T3 Dump KL 5 produc`on angle T1 High- p/π15 COMET K10 Separated beam up to 10GeV/c K: 10 6 /spill p bar : 10 7 /spill S=-3 physics charmed- baryon spectroscopy H.Takahashi, Parallel- 4 on Oct.1 24

25 Summary E19 and E27 pilot run were successfully carried out. 3 beam cycles by summer 2013 with 10-20kW beam. 6 Li(π -,K + ) 6 Λ H (E10), γ- ray spectroscopy for 19 Λ F and 4 ΛHe (E13) Facility upgrades in near future New K1.1 beam line and SKS@K1.1 will be operated from High- p/π15 and COMET beam lines from 2015 in the earliest case. Experiments 10,11 Λ B and 7 Λ Li (E13), 2N- induced NMWD of 12 ΛC (E18) at K1.1 Emulsion exp. (E07), spectroscopy of 12 ΞBe (E05) at K1.8 Σp scawering (E40), H- dibaryon (E42) Hadron hall extension under considera`on 25

26 backups 26

27 Accelerator report at 15 th J- PARC PAC Mee`ng (July 13 15, 2012) 27

28 Approval Summary (Sep ) Total Stage Stage- 1 2 Test- Exp. 5 Deferred Stage- 2 8 Stage- 1 6 Deferred 1 28

29 29

30 30

Atsushi Sakaguchi (Osaka University) for the J-PARC E10 Collaboration

Atsushi Sakaguchi (Osaka University) for the J-PARC E10 Collaboration Some properties of Λ hypernuclei Property 1: glue-like role of Λ hyperon Some examples of the glue effect particle unstable Λ hyperon