Yoshiyuki Miyachi Tokyo Institute of Technology Strange Spin measurements at J-PARC Strange spin inside the proton Neutrino scattering and Δs Δs measurement.

Presentation on theme: "Yoshiyuki Miyachi Tokyo Institute of Technology Strange Spin measurements at J-PARC Strange spin inside the proton Neutrino scattering and Δs Δs measurement."— Presentation transcript:

1 Yoshiyuki Miyachi Tokyo Institute of Technology Strange Spin measurements at J-PARC Strange spin inside the proton Neutrino scattering and Δs Δs measurement at J-PARC (NeuSpin) NeuSpin: 柴田利明，武居秀行、宮地義之（東工大） 齊藤直人（京大）、酒見泰寛（ RCNP ）

2 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Strange spin inside proton - EMC results - Nucl. Phys. B328 (1989) 1, Phys. Lett. B206 (1988) 364 = + + Proton spin: EMC: 1/2

3 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング E734, Phys. Rev. D35 (1987) 785 Neutral current cross section → strange axial form factor Liquid scintillator + Drift Tube 170 t 0.5E19 POT for neutrino 2.5E19POT for anti-neutrino From G A s (Q 2 ) to s Further analysis: (Alberico et al.) -0.21 < s < 0 strong correlation with the axial mass M A Neutrino scattering and s - E734 results -

4 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Beam flux – 1 GeV for “on-axis” – < 1GeV for “off-axis” 10 21 POT/year (130 days) – 30 times BNL-E734 anti-neutrino beam – neutrino anti-neutrino asymmetry measurement J-PARC - beam line

5 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Experiment at J-PARC Off-axis (2.5 º ): Narrow band, Peak energy < 1.0 GeV – Small background from resonance and DIS events Liquid scintillator with different H/C mixture – FINeSSE type detector: Readout with WLS fiber – e.g Bicron BC510A (H/C=1.212) and BC-533 (H/C=1.96) Pure Carbon can be extracted for nA Xsection – e.g. 5x5x5m 3 ~ 125 t – Recoil proton (T p = 50 〜 400 MeV: Q 2 = 0.1 〜 0.8 GeV 2 ) High pressure hydrogen TPC dedicated for low Q 2 measurements? 1E21 POT possible in one year (130 days) – 30 times BNL-E734

6 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング NC-p yield estimation J-PARC Neutrino Flux MC data ⇒ 1E21 POT ⇒ Off-axis (2.5°) ⇒ 280 m position (T2K ND location) Liquid Scintillator active target ⇒ BC533 ⇒ 16 ton (2.5x2.5x2.5 m) Neutrino Interaction Generator ⇒ NEUGEN With different Δs values ⇒ -0.1, 0.0, 1.0 ⇒ Only affect strange axial form factor E734 J-PARC

7 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング BC533 H:C =1.96:1 ρ=0.8 g/cm 3 BC501A H:C =1.12:1 ρ=0.874 g/cm 3 on H + extracted --- generated on C + extracted --- generated

8 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング FINeSSE Fermilab Intense Neutrino Scattering Scintillator Experiment FINeSSE detector Prototype Liq. Scintillator readout with WS fibers Proposal:Fermilab LOI:BNL

9 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング FINeSSE vertex detector performance FINeSSE Proposal, hep-ex/0402007 NC-p Detection Efficiency CCQE Detection efficiency About 50% detection efficiency for NC-p (0.2 < Q 2 < 0.5 GeV 2 ) ⇒ Promising Improvement around Q 2 = 0.1 GeV 2 is needed. Next step: Include similar detection efficiency in the estimation Build the detector simulation

10 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング NeuSpin activities Presentations: NP04 and NP04 neutrino session “Determining strangeness quark spin in neutrino scattering at J-PARC (T.-A. Shibata)” “Polarized Parton Distributions in the Nucleon (Y. Miyachi)” “Strangeness Spin Contribution to the Nucleon Spin measured at J-PARC (N. Saito)” NuFact05, June, 2005, Rome “Study for the Neutrino Coherent Pion Production Experiment (Y. Sakemi)” NuInt05, September, 2005, Okayama “ Strangeness in Nucleon -- a summary from electron scattering experiments and projection on neutrino scattering experiment (Y. Miyachi)” PANIC05 satellite meeting. “Strange Spin Measurements at J-PARC (Y. Miyahci)” Workshop on hadron structure at J-PARC, Dec. 2005, KEK “(Y. Miyachi)” 核子スピン構造に関する最近の発展と今後の展望, March 10, 2006, KEK “(N. Saito)” R&D: Liquid scintillator test and detector simulation NeuSpin: http://www.nucl.phys.titech.ac.jp/~neuspin/ ＲＣＮＰワークショップ「ニュートリノと原子核・核子の反応」 2005/02/24 、 RCNP 1 st NeuSpin meeting on Feb. 24, 2006 at Tokyo Tech Mailing list for the working group: nu-spin-jparc@nucl.phys.titech.ac.jp if you are interested, just send an empty E-mail to nu-spin-jparc-help@nucl.phys.titech.ac.jp

11 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング これからの予定： ― Workshop DIS2006 の前日（４月１９日） ― LOI: ４月 ― SciBooNE 実験（ FNAL 、２００６年秋・冬測定開始予定 ）

12 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング

13 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Extraction of N NC N BICRON:H/Cρ(g/cm 3 )ρ H (g/cm 3 ) ρ C (g/cm 3 ) BC501A1.2120.8740.1120.688 BC5331.960.80.0800.794 Using two liquid scintillators with different mixture of H and C: Nuclear effect free extraction:

14 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Proton spin problem = + + Proton spin: The most naive case: Naive parton model: Assuming SU(3) flavor symmetry, taking axial current matrix if s = 0, = a 8 = 0.58 From weak decay: Δq corresponds to axial form factor

15 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Strangeness spin inside proton - HERMES results - assuming Δq(x)=0 Phys. Rev D 71 (2005) 012003

16 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Strangeness Spin in the nucleon – Key for understanding the proton spin problem – Is Δs positive, negative or zero? Neutrino scattering – Unique tool for studying strange spin inside nucleon nucleon axial form factor measurement via neutral current elastic scattering – Key points: nuclear effects, Q 2 extrapolation to Q 2 =0 – Measurement at J-PARC: Feasibility study is on going. – It seems possible to extract NC-p on H with two type of liq. Scinti. targets using FINeSSE type vertex detector Summary

17 Neutrino-Nucleon Scattering Measurement of strange spin inside nucleon

18 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Contents Strangeness in nucleon – Strangeness in nucleon – Proton spin problem HERMES results Neutrino scattering – E734 – Strange spin measurement at J-PARC Summary

19 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Neutrino-Nucleon scattering Neutral Current NC-EL/CC-QE

20 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング HERMES at DESY DES Y HERME S gas targets: unpol. (H, D, Ne, Kr, Xe) long. pol. (H, D) trans. pol. (H) HERA: pol. electron/positron @ 27.5GeV polarization about 55%

21 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Iso-scalar method - strangeness spin extraction - Alternative method to extract Δs(x) Data: Deuteron target Inclusive asymmetry K + +K - asymmetry K multiplicity Free from Fragmentation model reduce systematic uncertainty

22 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Neutrino elastic scattering cross section 0.4 0.6 0.8 1.0 GeV E734 FINeSSE J-PARC? E734, Phys. Rev. D35 (1987) 785

23 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Strangeness in nucleon DIS inclusive measurement: DIS semi-inclusive measurement: Baryon magnetic moment: Lattice calculation: π-N Σ-term:strange scalar density OZI rule violation:polarized strangeness Parity violating electron scattering:

24 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング CC yield estimation

25 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Flavor tagging in DIS Flavor Tagging: Hadron carries information on quark flavor through fragmentation function Structure Function Parton Distribution Fragmentation

26 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Strangeness outside the coverage http://durpdg.dur.ac.uk/hepdata/pdf3.html CTEQ5: ?

27 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Other impacts of  s measurements Neutron EDM (J. Ellis and R. A. Flores PLB377 (1996) 83) – n-EDM predicted using q-EDM and Δ q Dark Matter (J.Ellis and M. Karliner hep-ph/9601280) – Better determination of Dark-Matter reaction

28 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング Sensitivity at J-PARC – Similar Detection Efficiency to E734: 7.6% for neutrino-N elastic, 5.4% for anti-neutrino-N elastic – However with lower Q 2 cut-off : 0.1 GeV 2 Achievable with more uniform detector – Hydrogen TPC was not included in this estimation. – 25 times more statistics but pure proton only 1/6 Factor 2 reduction in statistical error – Systematic control improvements to ~5% E734 7.6% dominated by Beam Flux and Nuclear Effects Possible to remove Nuclear Effects which could be larger in lower Q 2 region

29 ２００６年３月２７日宮地 義之、東工大理日本物理学会「ハドロン物理」インフォーマルミーティング