TENSOR AND VECTOR ANALYZING POWERS OF d ↑ d → pT and d ↑ d → pX REACTIONS AT 270 MEV

1. TENSOR AND VECTOR ANALYZING POWERS OFd↑ d→pTandd↑ d→pXREACTIONS AT 270MEV T.A.Vasiliev1†, T.Saito2, V.P.Ladygin1, M.Hatano2, A.Yu.Isupov1, M.Janek1,5, H.Kato2, N.B.Ladygina1, Y.Maeda7, A.I.Malakhov1, S.Nedev6, J.Nishikawa4, H.Okamura8, T.Ohnishi3, S.G.Reznikov1, H.Sakai2, S.Sakoda2, N.Sakomoto3, Y.Satou2, K.Sekiguchi3, K.Suda7, A.Tamii9, T.Uesaka7, N.Uchigashima2, K.Yako2 1 LHE JINR, Dubna, Moscow region, 141980 Russia2 Department of Physics, University of Tokyo, Tokyo 113-0033, Japan3 The Institute of Physical and Chemical Research (RIKEN), Wako 351-0198, Japan4 Department of Physics, Saitama University, Saitama 338-8570, Japan 5 University of P.J.Safarik, 041-54 Kosice, Slovakia 6 University of Chemical Technology and Metallurgy, Sofia, Bulgaria7 Center for Nuclear Study, University of Tokyo, Tokyo 113-0033, Japan8 Cyclotron and Radioisotope Center, Tohoku University, Sendai, Miyagi 980-8578, Japan9 Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan†vasiliev@sunhe.jinr.ru

2. Abstract Complete set of thebeam deuteron analyzing powers of thed↑d→pT reaction at 270MeV is obtained. The angular distributionsof the tensor AYY, AXX, AXZ and vector Ay analyzing powers were measured inangular range from 90O to 180O in c.m.s. The d↑d→pX data on AY, AYY and AXX near breakup threshold are also obtained. The experimental data in these kinematical conditions are sensitivemostly to the spin structure of deuteron. 1 Introduction 2 Experiment 3 Analysis Derivation of Beam Polarization Derivation of Analyzing Powers 4 Results and Discussion 5 Summary

3. Introduction One Nucleon Exchange reaction like d↑ p → p↑ d T20, k0 Saclay, Dubna d↑ p → p d↑ k0, dσ/dΩ, Ay,Ayy,Axx,Axz 250 MeVRIKEN p↑ d → d↑ p Ay (p), Ay (d) 150, 190 MeV KVI d↑ 3He↑→p 4He C// 140, 200, 270 MeV RIKEN d↑ d→pT and d↑ d→pX Ay,Ayy,Axx,Axz140, 200, 270 MeV RIKEN • are the simplest processes with a large momentum transfer • ↓ • 1. These reactions could be used as a tool to study the deuteron structure at short distances; • 2. Polarization observables of these reactions are sensitive to the D/S wave ratio in deuteron. • The goal of this report is to present the data on the tensor and vector analyzing powers • AYY, AXX, AXZ andAY for the reaction d↑ d→pT obtained in R308n experiment at RIKEN. • Also the data for the breakup reaction near threshold d↑ d→pX are shown. • The relative momenta of nucleons in deuteron achieves ≈ 400 MeV/c at energy • Ed=270MeV.

4. Experiment

5. Experiment Magnetic Spectrometer SMART

6. Derivation of Beam Polarization The deuteron vector and tensor polarizations with respect to the cylindrically symmetric axis Z are defined by 1. SwingerPOL 2. DroomPOL PIS: Mode 0: (pZ,pZZ)=(0,0) Mode 1: (pZ,pZZ)=(0,-2) Mode 2: (pZ,pZZ)=(-2/3,0) Mode 3: (pZ,pZZ)=(1/3,1) The differential cross section normalized by the unpolarized one is given by

7. Derivation of Beam Polarization Amp1.vs.Amp2 Amp1.vs.TOF1 The amplitude correlation between signals from the deuteron detector and RF. true TOF1-TOF2 Time-of-flight coincidence for the deuteron and proton detectors. background

8. Derivation of Beam Polarization

9. The tensor Pyy and Pxz polarization elements for Axz data at 270 MeV. sw=41O sw=14O sw=21O sw=7O sw=28O sw=34O sw=48O

10. Derivation of Analyzing Powers Definition of the scattering angles and the coordinates: at the target at the spectrometer

11. Derivation of Analyzing Powers Amp1.vs.Amp2 Amp1.vs.TDRF The amplitude correlation between the signals from the first plastic scintillator and RF-TDCtrig. The amplitude correlation between signals from the first and the second plastic scintillators. d p 

12. Derivation of Analyzing Powers Typical example of the obtained energy spectra of d↑ d→pT reaction at emission angles Θcm=175 (a) and 103 (b).

13. Derivation of Analyzing Powers The normalized cross section for the spin mode M (M=1,2,3) are defined as:

14. The experimental results on Ay, Ayy, Axx andAxz analyzing powers of d↑d→pT reaction at Ed 270 MeV.

15. The experimental results on T20, T21 andT22 analyzing powers of d↑d→pT reaction at Ed 270 MeV.

16. Typical example of the obtained excitation energy spectra after Ex(d+CD2) - k*Ex(d+C) subtraction atΘcm=8c.m.s. ___ d↑d→p dn ___ d↑d→p ppn

17. The experimental results on Ay, Ayy and Axx analyzing powers of d↑d→pX reaction at Ed 270 MeV.

18. Summary • The experimental data on the tensor and vector analyzing powers Ayy,Axx, Axz and Ayfor d↑d→pT are obtained at Ed=270MeV in angular range of 90o-1800 in the c.m.s. • The experimental data on tensor analyzing powers of this reaction show sensitivity to the spin structure of deuteron. • The angular distribution of Ay indicates the necessity of description of the reaction mechanism beyond the ONE. • The experimental data of the tensor and vector analyzing powers Ayy, Axxand Ay for d↑d→pX breakup reaction are obtained. • The experimental data on Ayy, Axxfor this reaction also show the sensitivity to the spin structure of deuteron. 6. The angular distribution of Ay of breakup reaction is the same as for the binary one within achieved experimental errors. 7. The interpretation of the obtained experimental data needs further development in theoretical approaches either to adequative descriptionof the light nuclei structure at short distances or taking into account mechanisms in addition to ONE.