reaction at energy Т d = 270 MeV.

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1 12 Vector and tensor analyzing owers in 13 reaction at energy Т d = 270 ev. C( d, С reaction at energy A.S.Kiselev 1, V.P.Ladygin, T.Uesaka,.Janek, T.A.Vasiliev,.Hatano, A.Yu.Isuova, H.Kato, N.B.Ladygina, Y.aeda, A.I.alakhov, S.Nedev, T.Saito, J.Nishikawa, H.Okamura, T.Ohnishi, S.G.Reznikov, H.Sakai, S.Sakoda, N.Sakomoto, Y.Satou, K.Sekiguchi, K.Suda, A.Tamii, N.Uchigashima, K.Yako 1 LHE JINR, Dubna, oscow region, Russia 2 Deartment of Physics, University of Tokyo, Tokyo , Jaan 3 The Institute of Physical and Chemical Research (RIKEN, Wako , Jaan 4 Deartment of Physics, Saitama University, Saitama , Jaan 5 University of P.J.Safarik, Kosice, Slovakia 6 University of Chemical Technology and etallurgy, Sofia, Bulgaria 7 Center for Nuclear Study, University of Tokyo, Tokyo , Jaan 8 Cyclotron and Radioisotoe Center, Tohoku University, Sendai, iyagi , Jaan 9 Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka , Jaan

2 Abstract In this work we resent the exerimental results on the tensor A yy and vector A y analyzing owers at T d = 270 ev for the C( d, C reaction in the angular range from 4 o to 18 o in lab. The data on the tensor analyzing ower T 20 for the d ( d, X and C( d, C reaction at energy 140, 200 and 270 ev and at emission angle = 0 are also obtained. Θ The exeriment was erformed at RIKEN Accelerator Research Facility (RARF, Jaan.

3 Introduction The interest in the exerimental and theoretical study of few nucleon transfer reactions has been renewed in the ast years mainly due to the ossibility to obtain information of astrohysical relevance from these reactions. Alternative indirect methods, such as the asymtotic normalization coefficient (ANC method, based on the analysis of breaku or transfer reactions, have been used as a tool to obtain astrohysical S-factors. Single-nucleon transfer reactions that robe the degrees of freedom of single articles have been extensively used to study the structure of stable nuclei. The analysis of such reactions rovides the angular momentum transfer, which gives information on the sin (j and arity ( π of the final state. Thanks to recent develoments in radioactive beam roduction and in the detection of light charged articles, transfer reactions can now be used to investigate the single-article structure of exotic nuclei. -1 -

4 d, The ( striing reaction has long been use as a means of robing the single article structure of nuclei. In articular, through distorted wave Born aroximation (DWBA analyses it has been used to determine the orbital angular momentum and sectroscoic factors of secific states in the recoil nucleus. 3 d( d, H d ( d, X The and rocesses concern to ONE (One Nucleon Exchange reactions. These reactions are the simlest rocesses with a large momentum transfer, so they could be used as a tool to study the deuteron structure at short distances. The olarization observables of these reactions are sensitive to the D/S wave ratio in the deuteron. -2 -

5 Exeriment -3 -

6 agnetic Sectrometer SART

7 Vector ( z and tensor olarization ( zz of deuteron beam The direction of symmetric axis of the beam olarization was controlled with a Wien filter located at the exit of olarized ion source (PIS. The deuteron vector ( z and tensor ( zz beam olarizations with resect to their cylindrically symmetric axis Z are defined by z = N N + zz = N + + N 2N 0 where N +, N - and N 0 denotes the fractions of deuteron beam in magnetic substates +1, -1 and 0, resectively. In this exeriment, four sin modes were used, whose ideal magnitudes of olarizations are -5-

8 ode 0 ( z, zz = (0,0 ode 1 ( z, zz = (0,-2 ode 2 ( z, zz = (-2/3,0 ode 3 ( z, zz = (1/3,1 The mode 0 - unolarized mode, mode 1 - ure tensor mode, mode 2 - ure vector mode and mode 3 is mixed mode. Results of measurements of olarization for three modes y ± Δ yy ± Δ ode 1 ode 2 ode ± ± ± ± ± ±

9 Detection and analysis P A P 1 A P 1 P P AP2 RF-TDC Correlation of the energy losses in the 1st and the 2nd scintillation detectors and radio frequency signal of the cyclotron -7 -

10 N d d 3 H E x = ( E E3N ( P0 P3 N N where P 0 - the incident momentum, E 0 = 2 d + T d the total initial energy, E 3N - energy of the three-nucleon system, P 3N - momentum of the three-nucleon system, N - the nucleon mass. d 12 C 13 С d d X CD 2 C subtraction for the at 270 ev. The oen histogram corresonds to the yield from CD 2 target, the shadowed histogram from carbon target, resectively. E x,ev -8 -

11 The reactions with excitation of levels of a nucleus 13 C d + 12 C + X 3 = f ff 0 where 0 = T ( T + 2 d f the final momentum, ff fieldfactor, Т the kinetic energy of incident article, d - the nucleon mass. -9-

12 12 C( d, omentum sectrum for reaction at 13 C Θ = 0 (140 ev g.s N Peaks corresonding to the 13 C states are labeled by their excitation energies in ev P,GeV -10-

13 Derivation of Analyzing Powers The cross section asymmetries: S = I Y e Y yield of the true events I integrated beam charge/deuteron charge e (WDC detection eciency*(live-time ratio of the data aquisition To obtain the values of the analyzing owers it is necessary to determine the normalized cross section for the sin mode (=1,2,3. It is exressed as N ex = = 0 S S = Q Q 0 e e 0 Y Y 0-11-

14 Equations for analyzing owers A y A yy mode: N N N 1 ex 2 ex 3 ex = = = yy 2 y 3 y A A A y y yy yy A yy A xx mode: N N 1 ex 3 ex = = xx 3 xx A A xx xx Θ = 0 at emission angle : ( A xx A yy T = (for 200 и 270 ev T 20 = 2 A xx (for 140 ev -12-

15 Results g.s. The exerimental results of T 20 analyzing owers * for C( d, C reaction at energy T d = 140, 200 and 270 ev at emission angle = 0. Θ -13-

16 The exerimental results of T 20 analyzing owers for d ( d, X reactions at energy T d = 140, 200 and 270 ev at emission angle = 0. Θ -14-

17 12 13 * The exerimental results of cross section for ( d, C reaction at energy T d = 140, 200 and 270 ev at emission angle = 0. Θ C -15-

18 d d C C C( g. s. C d C C( g. s * d C C * The exerimental results on the tensor A yy and vector A y analyzing owers for the 12 C( d, 13 C reaction at energy T d = 270 ev in the angular range from 4 o to 18 o in lab. -16-

19 Summary The exerimental results on the tensor A yy and vector A y analyzing * owers at T d = 270 ev for the C( d, C reaction in the angular range from 4 o to 18 o in lab. are obtained * The data on the tensor analyzing ower T 20 for the C( d, C. and d ( d, X reactions at energy 140, 200 and 270 ev and at emission angle = 0 are obtained also. Θ The exerimental data on T 20 for these reactions shows sensitivity to the sin structure of deuteron * The negative sign of analyzing ower T 20 for C( d, C and d ( d *, X reactions and ositive sing of A yy for C( d, C reflect D/S ratio a comonents of wave function of deuteron. The tensor analyzing ower T 20 has negative value as for binary reaction as breaku reaction of deuteron. The reactions with excitation of levels of a nucleus 13 C have negative value also

20 Thank You for the attention!

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