RIKEN/Tokyo-Russia Collaboration of Polarized Deuteron Experiments CNS, Univ. of Tokyo T. Uesaka

Polarized Deuteron Beam Polarized Deuteron unique probe to isoscalar spin excitations missing collectivity in nuclei (V  mode) N* excitations tensor polarization observables direct signature of tensor interaction smallest nuclei indispensable tool in few body physics TECHNICALLY difficulty in manipulating particle with spin ONE and small magnetic moment

RARF140 － 270 MeV Spin-isospin excitation via (d, 2 He) and (d,d’) reactions 3N force effects via d+p elastic scattering short-range structure of deuteron, 3 He Polarization axis can be freely controlled Wien Filter system single turn extraction Maximum intensity > 100nA on target Polarized Deuteron Beam at RIKEN E d =880MeV at RIBF

Polarized Deuteron Beam at JINR Nuclotron (new machine) super-conducting strong focus E d < 12 GeV

Physics Programs with Nuclotron Nucleon Structure Nuclear Structure short-range structure of deuteron and 3 He Medium effects on particle production Modification of nuclear matter Hypernuclei and  nuclei With booster cycle: 10 s

Cumulative Production and d Structure “Cumulative Production” (A.M.Baldin, prev. director of LHE, JINR) production of energetic particle which is impossible in nucleon-nucleon kinematics. Deuteron induced “cumulative” proton production can be a unique probe to deuteron structure at short distances approach to QCD prediction strange structures in the resonance region T.Aono et al., PRL 74 (1995) L.S. Azhgirey et al., PLB 391 (1997) 22. A.A.Nomofilov et al., PLB 325 (1994) 327.

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 (CUPID3 project) approved 2004 Mar. Collaboration Agreement between Univ. Tokyo and JINR 2004~ development of deuteron polarimeter RIKEN/Tokyo-Russia Collaboration

EXPERIMENT at RIKEN

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

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

EXPERIMENT at JINR

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. CUPID3 Project at Nuclotron

2002 Apr. Approved 1000 hours (including test machine time) ~2004 no progress due to insufficient intensity of polarized deuteron beam (~10 7 cps) for the spin correlation measurement intensity of ~ 10 9 cps is necessary. This is partly due to the short injection time of Nuclotron (8ms) compared with the previous Synchrophasotron. CUPID3 Project at Nuclotron

POLARIS (Pilipenko) long pulse duration vector OR tensor polarization separate experiments for vector and tensor measurements different polarimetry for vector and tensor polarizations vector: d+p quasi-elastic scattering tensor: deuteron breakup reaction IUCF (Derenchuk) → to Duban in this year short pulse operation → increase of beam intensity by two orders of magnitude vector AND tensor polarization simultaneous measurement of vector and tensor observables NEED new polarimetry for both vector and tensor polarizations Polarized Ion Source at Nuclotron

Large vector and tensor analyzing powers Coincidence measurement of deuteron and proton Simple detector system with plastic scintillators CH 2 can work as a hydrogen target Established at intermediate energies d+p Scattering as a deuteron polarimetry

d+p Elastic Scattering at GeV energies 1.06 GeV: J.S. Vincent et al., Phys.Rev.Lett.24 (1970) GeV : E. Winkelmann et al., Phys.Rev. C21 (1980) GeV : G.W. Bennett et al.,Phys.Rev.Lett.19 (1967) 387. approximate t-scaling considerably large A y, A yy even at backward angles

Internal Target Station of Nuclotron

2004 June run Beam Lifetime measurement with CH 2 target  = 10s for 2  m-thick target 2004 November-December run detector test evaluation of accidental coincidence 0.88 － 2 GeV 2005 February-March run measurement of vector and tensor analyzing powers at 7 energies (0.88, 1.0, 1.25, 1.5, 1.6, 1.75, and 2.0 GeV) RIBF energy Schedule

Collaborators