Hypernuclear magnetic moments

Transcription

1 The HypHI HI project at GSI/FAIR Hypernuclear spectroscopy with heavy ion collisions ons Progress Report Take R. Saito for the HypHI collaboration Helmholtz-University Young Investigators Group VH-NG-239 GSI-Darmstadt Helmholtz Center for Heavy Ion Reserach and Johannes Gutenberg-Universität Mainz

2 How much can we extend the s=-1 landscape? Around the β-stability line (π +,K + ), (K -,π π - ), (ee K (e,ek + ) with a stable target BNL, KEK, J-PARC, CEBAF, FINUDA, MAMI C Neutron rich hypernuclei (K -,π π + ) with a stable target J-PARC, FINUDA Toward hypernuclei at necleon drip-lines: Hypernuclei at extreme isospins Heavy ion collision HypHI, JINR

3 How much can we extend the s=-1 landscape? Hypernuclear magnetic moments Around the β-stability line (π +,K + ), (K -,π π - ), (ee K (e,ek + ) with a stable target BNL, KEK, J-PARC, CEBAF, FINUDA, MAMI C Neutron rich hypernuclei (K -,π π + ) with a stable target J-PARC, FINUDA Toward hypernuclei at necleon drip-lines: Hypernuclei at extreme isospins Heavy ion collision HypHI, JINR

4 Goals of the HypHI project Hypernuclear magnetic moments Quark bulding blockes Quark Pauli blocking effect Λ/Σ coupling as functions of isospins Kaon currents in the nuclear matter Hypernuclei at extreme isospins Cold neutron matter Λ/Σ coupling Long-lived hypernuclear isomer Charge symmetry breaking in baryon-baryon interactions

5 Hypernuclei with Heavy Ion Beams: The HypHI project Heavy ion induced reaction at relativistic energies (heavy-ion collision) i NN -> ΛKN : Energy threshold ~ 1.6 GeV Heavy ion beams with E > 1.6 GeV/u needed Stable heavy ion beam at GSI Stable heavy ion beam at FAIR RI-beam from FRS and super-frs Large Lorentz factor γ (>3) Effective lifetime : Longer by the Lorentz factor 200 ps -> 600 ps with γ=3 200 ps -> 4 ns with γ=20 target Λ projectile p Λ Hypernuclei with multiple-strangeness Only a few light hypernuclei so far identified with heavy ion beams at Dubna ( 3 ΛH H and 4 ΛH, ~ 0.2 μb, with 4 He and 7 Li beams) K +

6 Hypernuclei with Heavy Ion Beams: The HypHI project Heavy ion induced reaction at relativistic energies (heavy-ion collision) i NN -> ΛKN : Energy threshold ~ 1.6 GeV Heavy ion beams with E > 1.6 GeV/u needed Stable heavy ion beam at GSI Stable heavy ion beam at FAIR RI-beam from FRS and super-frs Large Lorentz factor γ (>3) Effective lifetime : Longer by the Lorentz factor 200 ps -> 600 ps with γ=3 200 ps -> 4 ns with γ=20 target Λ projectile p Λ Hypernuclei with multiple-strangeness Only a few light hypernuclei so far identified with heavy ion beams at Dubna ( 3 ΛH H and 4 ΛH, ~ 0.2 μb, with 4 He and 7 Li beams) K +

7 HypHI at GSI/FAIR: Concept of Experiments Produced hypernucleus at the similar velocity of projectiles Large Lorents factor γ > 3 200ps -> 600ps (γ=3), hypernuclear decay in flight Example : 12 C + 12 C -> A ΛZ + +,0 Λ Z K + X target Mesonic weak decay Λ -> π - + p Non-mesonic weak-decay Λp -> np Λ-Hypernucleus Magnet n Scintillators + diamond Trackers N-detector K + counter K Residues p, π

8 Phase 0 of HypHI The goal of the Phase 0 experiments To confirm Dubna s hypernuclear production at 2 A GeV with 6 Li primary beams : Mesonic decay Λ -> π - + p 3 Λ H -> π He 4 H -> π Λ He 5 Λ He -> π He + p

9 Hypernuclear events Z=1, 2 π - Polycrystalline diamond

10 ALADiN magnet

11 vertex Fiber detectors TR0: Particles from the target, primary x and y planes HAMAMATSU H7260KS readout Time readout by VUPROM Energy readout by CAEN QDC TR1 and TR2: Secondary vertex x, y and d planes HAMAMATSU H7260KS readout Time readout by VUPROM Used for tracking triggers Z=1, 2 Kuraray fiber, φ 0.83 mm Polycrystalline diamond π -

12 vertex Fiber detectors TR0: Particles from the target, primary x and y planes HAMAMATSU H7260KS readout Time readout by VUPROM Energy readout by CAEN QDC TR1 and TR2: Secondary vertex x, y and d planes HAMAMATSU H7260KS readout Time readout by VUPROM Used for tracking triggers Z=1, 2 Kuraray fiber, φ 0.83 mm Polycrystalline diamond 1088 channels, 34 PMTs π -

13 TOF walls TOF-start (new development) Plastic strip detector High rate: 10 7 /s Time resolution: ~ 200 ps ALADiN TOF wall (existing) Plastic scintillator bars For negative charged particles (mainly π - ) Horizontal(x)-vertical(y) (y) tracking Time resolution: ~ 200 ps Z=1, 2 π - Polycrystalline TOF+ diamond (new development) Plastic scintillator bars For positive charged particles xy tracking Time resolution: ~ 200 ps

14 Level 1 trigger: Tracking target TR2 TR0 TR1 Z=1, 2 Polycrystalline diamond Vertex out of the target Hypernuclear decay Free-Λ decay π - FPGA/DSP based trigger module Efficiency to 4 ΛH H π - α decay channel : ~ 14 %

15 Level 1 trigger: Tracking Purely VME based 256 channels I/O LVDS Fast logic calculations with a large FPGA at 400 MHz Slow complicated calculations by DSP at 1 GHz Data transfer to the VME bus Mass production: 80 modules

16 Level 2 trigger: π - π - from the target: mid rapidity, low momentum π - from hypernuclear decay: Lorentz boosted, large momentum Hit in ALADiN TOF wall 28 % for 4 ΛH π - α decay channel Z=1, 2 π - Polycrystalline diamond

17 Level 3 trigger: Z>0 Level 1+2+3: 7% efficiency for 4 ΛH π - α decay channel. Z=1, 2 Background: down to %. 3 H Λ H -> 3 He + π -, 4 ΛH -> 4 He + π -, 5 Λ He -> 4 He + p + π - 4 Λ He -> d + d π - Polycrystalline diamond Z=1 or 2 particles hit in TOF+ 95 % for 4 ΛH π - α decay channel

18 Additional detectors TPC from BRAHMS, NBI Polycrystalline diamond Drift chambers from KEK Position resolution: ~ 200 μm

19 FOPI C target Test experiment in September T1 Plastic fingers Fiber with 4-layers Diamond Fiber with 2-layers T2 Aerogel Plastic bars Detectors at 10 degrees 58 Ni beams at 1.9 A GeV and 0.85 A GeV 12 C beams at 0.85 A GeV Event by event PID by TOF and ΔE E measurements Protons, He and Li

20 PID p α pp Li Be Be+α B

21

22 SciFi detectors: Energy resolution 4 Λ H α π - α Λ p π - 4 layers SciFi

23 SciFi detectors: Cluster size 4 layers SciFi 2 layers SciFi

24 SciFi detectors: Position resolution 4 layers SciFi, proton 4 layers SciFi, α

25 SciFi detectors: Time resolution

26 VUPROM: TDC readout

27 Feasibility of the TOF+ trigger -> Takeshi Mochizuki

28 Estimates for Phase 0 4 Λ H Beam: 6 Li, 10 7 /s, 2 A GeV Target: 12 C, 8 g/cm 2 Trigger rate: < 1 khz 7 shifts for test experiments (3 shifts spent) 28 shifts for the physics run End of 2008 or beginning of 2009 Expected in 2.7 days With drift chambers 3 MeV < 1.5 MeV Much less background What to be measured: Cross section Lifetime Polarization Forward correlation between Λ and other charged particles Σ hypernuclei

29 HypHI Project at GSI/FAIR HypHI project started LOI and progress report to the GSI PAC, Design study Design study, preparation for the phase 0 experiment Phase 0: experiment with 3 ΛH, 4 Λ H and 5 ΛHe Design study for the setup for hypenuclear non-mesonic weak decay measurements Phase 1: Experiments for proton- rich hypernuclei Phase 2: Experiment for neutron- rich hypernuclei at R3B/NuSTAR/FAIR ~2011 Phase 3: Hypernuclear separator Hypernuclear magnetic moments Hypernuclear drip-lines

30 HypHI Project at GSI/FAIR HypHI project started LOI and progress report to the GSI PAC, Design study Design study, preparation for the phase 0 experiment Phase 0: experiment with 3 ΛH, 4 Λ H and 5 ΛHe Phase 0 > 10 3 /week > 10 4 /week Design study for the setup for hypenuclear non-mesonic weak decay measurements Phase 1: Experiments for proton- rich hypernuclei Phase 2: Experiment for neutron- rich hypernuclei at R3B/NuSTAR/FAIR ~2011 Phase 3: Hypernuclear separator Hypernuclear magnetic moments Hypernuclear drip-lines

31 HypHI Project at GSI/FAIR HypHI project started LOI and progress report to the GSI PAC, Design study Design study, preparation for the phase 0 experiment Phase 0: experiment with 3 ΛH, 4 Λ H and 5 ΛHe Phase 0 Phase 1 > 10 3 /week > 10 4 /week Design study for the setup for hypenuclear non-mesonic weak decay measurements Phase 1: Experiments for proton- rich hypernuclei Phase 2: Experiment for neutron- rich hypernuclei at R3B/NuSTAR/FAIR ~2011 Phase 3: Hypernuclear separator Hypernuclear magnetic moments Hypernuclear drip-lines

32 Collaboration with JINR/Dubna Stable heavy ion beams up to 3.7 A GeV, up to 12 C Larger L production cross section More Lorentz boost Fruitful to study hypernuclear production mechanism

33 Collaboration with JINR/Dubna Stable heavy ion beams up to 3.7 A GeV, up to 12 C Larger L production cross section More Lorentz boost Fruitful to study hypernuclear production mechanism

34 HypHI Project at GSI/FAIR HypHI project started LOI and progress report to the GSI PAC, Design study Design study, preparation for the phase 0 experiment Phase 0: experiment with 3 ΛH, 4 Λ H and 5 ΛHe Phase 0 Phase 1 > 10 3 /week > 10 4 /week Design study for the setup for hypenuclear non-mesonic weak decay measurements Phase 1: Experiments for proton- rich hypernuclei Phase 2: Experiment for neutron- rich hypernuclei at R3B/NuSTAR/FAIR Phase 3: Hypernuclear separator Hypernuclear magnetic moments Hypernuclear drip-lines ~2011 Phase 2

35 HypHI Project at GSI/FAIR HypHI project started LOI and progress report to the GSI PAC, Design study Design study, preparation for the phase 0 experiment Phase 0: experiment with 3 ΛH, 4 Λ H and 5 ΛHe Phase 0 Phase 1 > 10 3 /week > 10 4 /week Design study for the setup for hypenuclear non-mesonic weak decay measurements Phase 1: Experiments for proton- rich hypernuclei Phase 2: Experiment for neutron- rich hypernuclei at R3B/NuSTAR/FAIR Phase 3: Hypernuclear separator Hypernuclear magnetic moments Hypernuclear drip-lines ~2011 Phase 3

36 The HypHI collaboration: since 2005 Giessen University, Germany GSI, Germany Institute for Nuclear Research, Russian Academy of Science, Moscow, Russia JINR, Dubna, Russia Johannes Gutenberg University Mainz, Germany KEK, Japan Kyoto University, Japan Moscow State University, Russia Nara Women s University, Japan Niels Bohr Institute, Denmark Osaka Electro-Communication University, Japan Osaka University, Japan Peking University, China RIKEN, Japan Soltan Institute for Nuclear Studies, Poland Tokyo University, Japan Tokyo University it of Science, Japan Tohoku University, Japan Still expanding Spokesperson : Take R. Saito, GSI

37 Hypernuclear physics group at GSI Take R. Saito Postdocs Shizu Minami -> Tenure track in EE department for HypHI Myroslav Kavatsyuk -> Tenure track at KVI for PANDA/HypHI Sebastien Bianchin Banu Ozel (from March 2008) Ph.D. students Daisuke Nakajima (from KEK/Tokyo) Christophe h Rappold Master students Olga Borodina Takashi Mochizuki (from Osaka, August ~ November 2007) Friedemann Zenke or Fatma Bulut (from March 2008) Electronics engineer and physicist Jan Hoffmann Nik Kurz Wolfgang Ott

38

39

40 SciFi detectors: Cluster numbers and distances 2 layers SciFi Cluster numbers Cluster distance M. Kavatsyuk