RIKEN/Tokyo-Russia Collaborationof Polarized Deuteron Experiments

CNS, Univ. of TokyoT. Uesaka

Polarized Deuteron Beam

Polarized Deuteronunique probe to isoscalar spin excitations

missing collectivity in nuclei (V mode)

N* excitationstensor polarization observables

direct signature of tensor interactionsmallest nuclei

indispensable tool in few body physics

TECHNICALLYdifficulty in manipulating particle with

spin ONE and small magnetic moment

RARF 140 － 270 MeVSpin-isospin excitation

via (d,2He) and (d,d’) reactions3N force effects via d+p elastic scatteringshort-range structure of deuteron, 3He

Polarization axis can be freely controlledWien Filter systemsingle turn extraction

Maximum intensity> 100nA on target

Polarized Deuteron Beam at RIKEN

R i n g C y c l o t r o n

5 0 m0

B e a m P a t h

P I S

A V F C y c l o t r o n

S p e c t r o g r a p h S M A R T

P o l a r i m e t e r

Ed=880MeV at RIBF

Polarized Deuteron Beam at JINR

Nuclotron (new machine)super-conductingstrong focusEd < 12 GeV

Physics Programs with Nuclotron

• Nucleon Structure• Nuclear Structure

short-range structure of deuteron and 3He• 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 predictionstrange structures in the resonance region

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.

• SubjectStructure of light nuclei at short-range, putting special focus on its spin dependences

• Brief history2000 Collaboration Agreement between RIKEN

and JINR ( ～ 2003)2000 Nov. 1st collaboration experiment

dd →n3He(p3H) measurement at RIKEN 2002 Apr. JINR proposal

3He(d,p)4He (CUPID3 project) approved2004 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)

3He Structure studied via d+d →3He+n

Results of R308n experiment

2000 November 1st experiment undercollaboration ofRIKEN/Tokyo-JINR

Lines:solid Urbanadashed Parisdots RSC

V.P. Ladygin, T. Uesaka et al., Phys. Lett. B 598 (2004) 47.

Ed=140, 200, 270 MeV

Tensor analyzing power T20

clear signature ofD-state effect in 3He

EXPERIMENT at JINR

• Spin Correlation Measurement of polarized deuteron beam and polarized 3He 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 ofpolarized deuteron beam (~107cps)

for the spin correlation measurement intensity of ~ 109 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 measurem

ents different polarimetry for vector and tensor polarizations

vector: d+p quasi-elastic scatteringtensor: deuteron breakup reaction

• CIPIOS @ IUCF (Derenchuk) → 　 to Duban in this yearshort pulse operation → increase of beam intensity by two orders of magnit

udevector 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 scintillatorsCH2 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) 236.1.6 GeV : E. Winkelmann et al., Phys.Rev. C21 (1980) 2535.2.0 GeV : G.W. Bennett et al.,Phys.Rev.Lett.19 (1967) 387.

approximate t-scalingconsiderably large Ay, Ayy even at backward angles

Internal Target Station of Nuclotron

• 2004 June runBeam Lifetime measurement with CH2 target

= 10s for 2m-thick target

• 2004 November-December rundetector test evaluation of accidental coincidence rate@ 0.88 － 2 GeV

• 2005 February-March runmeasurement 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

Yu.S.Anisimov, O.Avramova, L.S.Azhgirey, V.K.Bondarev, J.Bunta, J.Charuba,

L.Dimitrov, S.Gmuca, Z.Guzik, K.Hatanaka, M.Hatano, E.Igorova,T.Ikeda, K.Itoh,

V.I.Ivanov, M.Janek, T. Kawabata Yu.-T.Karachuk, T.L.Karavicheva, E.V.Karpechev,

J.Kliman, V.A.Krasnov, A.N.Khrenov, A.D.Kirillov, B.Kunov, A.B.Krepin, S.N.Kuznetsov,

V.P.Ladygin , Y.Maeda, A.I.Malakhov, P.K.Manjakov, G.Martinsky, B.Matoushek,

S.Nedev, T.Ohnishi, H.Okamura, V.N.Penev, E.B.Plekhanov, A.I.Reshetin, S.G.Reznikov,

P.A.Rukoyatkin, T.Saito, H.Sakai, Y.Sakemi, Y.Satou, K.Sekiguchi, K.A.Shileev,

G.D.Stoletov, K.Suda, A.Tamii, A.A.Titov, A.A.Toropin, I.Tsakov, J.Urban, T.Uesaka,

T.A.Vasiliev, T.Wakasa, T.Wakui, K.Yako, V.N.Zhmyrov

CNS, Univ. of Tokyo, JINR,RIKEN, Institute of Nuclear Research and Nuclear Energy,University of Tokyo, National Institute of Research and Development for Optoelectronics,Saitama University, University of Chemical Technology and Metallurgy,RCNP, Osaka University, Institute of Physics Slovac Academy of Sciences,Tohoku University Soltan Institute for Nuclear Studies,

P.J.Safarik University,Institute for Nuclear Research RAS,St.-Petersburg State University