1. DSS Project Probing the Deuteron short-range Spin Structure in the (d,p) reactions using polarized deuteron beam at Nuclotron-M Spokespersons: V.P. Ladygin, A.I. Malakhov, T. Uesaka JINR P.J.Safarik University (Slovakia) Advanced Research Institute for Electrical Engineering (Romania) University of Chemical Technology and Metallurgy (Bulgaria) Institute for Nuclear Research (Russia) Belgorod State University (Russia) University of Tokyo RIKEN Saitama University

2. Scientific motivation Contemporary problems in nuclear force studies Nuclear force in the SHORT-RANGE region Central subject in Synchrophasotron / Nuclotron experiments. long standing, unsolved phenomena Studies with hadronic probes will provide new insights complimentary to that obtained in recent electromagnetic studies at JLAB Spin correlation measurement in 3 He(d,p) 4 He will shed a new light on the short-range structure of deuteron. MANY-NUCLEON FORCE effects Existence of Fujita-Miyazawa type 3NF is "established". Several "NEW" 3NFs are proposed, but not established experimentally. Relevance to wide-spread field in nuclear/hadron physics Nuclotron experiment will contribute to reveal new aspects of 3NF.

3. Relation to previous projects LNS Project (2001 － ) deuteron breakup dd→p 3 H/n 3 He PHe3 Project (2002 － ) 3 He(d,p) 4 He dp elastic measurements @ internal target of Nuclotron polarimetry at 0.9 － 2 GeV 3NF study DSS Project (2010 － ) JINR-U-Tokyo AGREEMENT on ACADEMIC EXCHANGE

4. Deuteron induced “cumulative” proton production can be a unique probe to deuteron structure at short distances d+p backward, deuteron breakup at JINR, SATURNE approach to QCD prediction strange structures in the resonance region Scientific program 1 : 3 He(d,p) 4 He T.Aono et al., PRL 74 (1995) 4997. L.S. Azhgirey et al., PLB 391 (1997) 22. A.A.Nomofilov et al., PLB 325 (1994) 327.

5. Spin Correlation Measurement of polarized deuteron beam and polarized 3 He target T. Uesaka et al., Phys. Lett. B 467 (1997) 199. T. Uesaka et al., Phys. Lett. B 533 (2002) 1. Scientific program 1 : 3 He(d,p) 4 He

6. 2002 Apr. Approved 1000 hours (including test machine time) ~2009 has been impossible to carry out the measurement due to insufficient intensity of pol. deuteron beam For the spin correlation measurement intensity of ~ 10 9 deuteron/sec is necessary. The new polarized ion souce (CIPIOS-based) is the best solution. In 2004, we started construction of a new polarimeter at ITS which is suited for a vector-tensor mixed polarized beam from the new ion source. (former) PHe3 Project at Nuclotron

7. ITS Polarimeter Setup 46 plastic scintillator 31 proton det. + 13 deuteron det. + 2 pp det. Tested in 2005 880 MeV → successful results In spite of its simple structure, the setup has sufficient event ID capabilities for d+p scattering.

8. Results at 1.6 GeV Beam Intensity 1  3 X 10 9 /spill (spill duration 8 sec) TDC & ADC spectra @ E d = 1.6 GeV Background is not negligible at higher energies, but seems to be within our control

9. Conclusions from 2005 run d+p elastic scattering E d = 880 MeV The d+p scattering can be a nice polarimetry at ~1GeV energies →submitted to NIMA Figure of Merit 270 MeV F=1.0 × 10  ⇔ comparable to RIKEN 880 MeV F=0.25 × 10  Optimization is necessary at higher energies target thickness detector solid angle angular coverage → data at 1 － 2 GeV required 3NF study at Nuclotron energies is possible and stimulating.

10. Scientific program 2 : dp scattering d  /d  at backward angles E p ≦ 135 MeV → need for 3NF E p = 250 MeV → inclusion of Fujita-Miyazawa type 3NF is not sufficient. Spin observables 3NF effects are not established 135 MeV 250 MeV 70 MeV 135 MeV 250 MeV 392 MeV with 3NF w/o 3NF

11. Scientific program 2 : dp scattering Beyond Fujita-Miyazawa 3NF Relativistic effect NEW 3NF (ring-type,  -  type, N* type, etc) ENERGY-SCAN at Nuclotron-M will reveal new physics which can not be seen in fixed-energy cyclotron experiments.

12. Yield estimation d  /d  lab (  cm ~60 － 140deg) 270 MeV 0.5 － 3 mb/sr 800 MeV 0.04 － 0.3 mb/sr 2000 MeV 0.005 － 0.25 mb/sr Beam intensity10 7 /sec (POLARIS) 10 9 /sec (new ion source) Effective target thickness10 22 /cm 2 → Luminosity 100 /mb/sec 10000 /mb/sr Solid angle2.2 msr / detector 1 mb/sr → 0.2 counts/sec → 24 hours to achieve  A=0.02 0.01 mb/sr → 0.2 counts/sec E d =2 GeV E d =270 MeV

13. Long-range plan ~ 2009201020112012 3 He(d,p) 4 He dp scattering New pol. Ion source 2×10 10 pps mixed pol. ITS setup One NIM paper One physics paper (in preparation) POLARIS 2×10 8 pps Preparation drift chambers/target (J) beamline/magnets (R) commissioning (R-J) Measurement d  /d  pol.  880 － 2000 MeV d  /d , pol. 300 － 800 MeV test at high E REQUEST 2010 2011 2012 Beam Time [h]50+20050+200250 (pol.) (pol.) (pol.) Budget33 k$33 k$24 k$ # contribution from Japan ~ 150 k$

14. Summary DSS project : a unification of LNS and PHe3. challenge to contemporary problems in nuclear force studies spin-correlation measurement in 3 He(d,p) 4 He reaction d+p elastic scattering → polarimetery & 3NF studies Construction of polarimeter at ITS Plan 2010d+p elastic scattering @ITS 300 － 800 MeV 2011d+p elastic scattering @ITS 880 － 2000 MeV 2012 3 He(d,p) 4 He This project will enhance activity of the in-house group of LHEP of JINR and will contribute education of younger generation at Dubna.

15. BACKUP SLIDES

16. Japanese part of the collaboration Members University of Tokyo~10 (3 staffs, 1 postdoc, 6 PhD students) RIKEN RCNP expertise in pol. target and in dp-measurement Budget contributions ITS polarimeter detectors, electronics, travel...~ 100k$ 3 He(d,p) 4 He pol. target, MWDC, travel...~ 150k$

18. Results at 2 GeV

22. Extension of cumulative production to study of 3N system Reaction mechanism theoretical study J.M. Laget et al., Nucl. Phys. A370 (1981) 479. before 2000, only cross section data available. polarization data, especially tensor analyzing power is necessary to probe the D-state effect in three nucleon system. 1st measurement of pol. observables at RIKEN (V.P.Ladygin) 3 He Structure studied via d+d → 3 He+n

23. Results of R308n experiment 2000 November 1st experiment under collaboration of RIKEN/Tokyo-JINR Lines: solidUrbana dashedParis dotsRSC V.P. Ladygin, T. Uesaka et al., Phys. Lett. B 598 (2004) 47. E d =140, 200, 270 MeV Tensor analyzing power T 20 clear signature of D-state effect in 3 He

24. Subject Structure of light nuclei at short-range, putting special focus on its spin dependences Brief history 2000 Collaboration Agreement between RIKEN and JINR ( ～ 2003) 2000 Nov. 1st collaboration experiment dd →n 3 He(p 3 H) measurement at RIKEN 2002 Apr. JINR proposal 3 He(d,p) 4 He (PHe3 project) approved 2004 Mar. Collaboration Agreement between Univ. Tokyo and JINR 2004~ development of deuteron polarimeter RIKEN/Tokyo-Russia Collaboration

25. Hit Pattern

26. Collaborators