V. P. Ladygin

Spin physics in few body systems at Nuclotron

The review of the recent results on spin effects in few nucleon systems obtained at LHEP-JINR are presented. The data on the deuteron analyzing powers in different reactions in the wide energy range demonstrate the sensitivity to the spin structure of the light nuclei. The future plans on the studies with polarized deuterons from new polarized ion source at Nuclotron will be reported.

Polarization Effects in Inelastic Deuteron Scattering in the Region of Baryon-Resonance Excitation

Within the impulse approximation, polarization effects in inelastic deuteron scattering on nuclei are investigated in the region around the resonance of mass about 2190 MeV/c2. It is shown that the spin-dependent part of the NN → NN*(2190) amplitude plays a significant role at high momentum transfers. Predictions are obtained for some polarization observables and cross sections for various deuteron-spin-flip processes.

Measurement of the tensor Ayy and vector Ay analyzing powers of the deuteron inelastic scattering of beryllium at 5.0 GeV/c and 178 mrad

Tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 5.0 GeV/c on beryllium at an angle of 178 mrad in the vicinity of the excitation of baryonic resonances with masses up to ∼ 1.8 GeV/c2 have been measured. The Ayy data are in good agreement with the previous data obtained at 4.5 and 5.5 GeV/c. The results of the experiment are compared with the predictions of the plane-wave impulse approximation and ω meson-exchange models.Tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with the momentum of 5.0 GeV/c on beryllium at an angle of 178 mr in the vicinity of the excitation of baryonic resonances with masses up to 1.8 GeV/c^2 have been measured. The Ayy data are in a good agreement with the previous data obtained at 4.5 and 5.5 GeV/c. The results of the experiment are compared with the predictions of the plane wave impulse approximation and omega-meson exchange models.

Deuteron beam polarimetry at the nuclotron

The scheme of the deuteron beam polarization measurements at Nuclotron are presented. A deuteron beam polarimeter based on the spin-asymmetry measurements in the dp-elastic scattering at large angles in center-of-mass system has been constructed at the internal target station at the Nuclotron of JINR. This polarimeter is planned to use for the measurements of the vector and tensor components of deuteron beam polarizations at the energies 270–2000 MeV simultaneously. Details on the low energy polarimeters are also discussed.

Angular dependences of the tensor analyzing powers in the dd → 3Hen reaction at intermediate energies

The tensor analyzing powers Ayy, Axx, and Axx in the dd → 3Hen reaction at intermediate energies are considered in the framework of the one-nucleon-exchange approximation. Their strong sensitivity to the 3He and deuteron spin structure at short distances is shown.

Measurement of the tensor analyzing power Ayy in the inelastic scattering of 4.5-GeV/c deuterons on beryllium at an angle of 80 mrad

The tensor analyzing power Ayy and the vector analyzing power Ay for the inelastic scattering of 4.5-GeV/c deuterons on beryllium nuclei at angle of about 80 mrad are measured in the vicinity of baryon-resonance excitation. These new data, presented as a function of t, comply well with the results of previous 4.5-, 5.5-, and 9-GeV/c measurements at zero angle in overlapping regions of t; all available data are described by a unified dependence on |t| upto about 0.9 (GeV/c)2. The experimental results are compared with the results of calculations performed within the multiple-scattering model and the model involving omega-meson exchange in the t channel.

Study of compressed baryonic matter at FAIR: JINR participation

The scientific goal of the CBM (Compressed Baryonic Matter) experiment at FAIR (Darmstadt) is to explore the phase diagram of strongly interacting matter at highest baryon densities. The physics program of the CBM experiment is complimentary to the programs to be realized at MPD and BMN facilities at NICA and will start with beam derived by the SIS100 synchrotron. The results of JINR participation in the development of different sub-projects of the CBM experiment are presented.

Investigation of the light nuclei spin structure from hadronic channels at NUCLOTRON

P.K.Kurilkin∗1, I.Dobrin2, V.V.Fimushkin1, D.A.Finogenov3, S.G.Genchev4, Yu.V.Gurchin1, A.P.Ierusalimov1, A.Yu.Isupov1, K.Itoh5, M.Janek6, E.V.Karpechev3, J.-T.Karachuk1,2, S.V.Khabarov1, T.Kawabata7, A.N.Khrenov1, V.A.Krasnov1, A.B.Kurepin3, A.K.Kurilkin1, V.P.Ladygin1, N.B.Ladygina1, D.Lipchinski2, A.N.Livanov1, Y.Maeda8, A.I.Malakhov1, G.Martinska9, S.M.Piyadin1, J.Popovichi2, A.N.Prokofichev1, V.L.Rapatsky1, A.I.Reshetin3, S.G.Reznikov1, P.A.Rukoyatkin1, S.Sakaguchi10, H.Sakai11,12, Y.Sasamoto13, K.Sekiguchi14, Ya.G.Skhomenko15, K.Suda12, V.V.Syschenko15, G.Tarjányiová6, A.A.Terekhin1, T.Uesaka12, J.Urban9, T.A.Vasiliev1, I.E.Vnukov15, N.I.Zamiatin1, E.V.Zubarev1

Measurement of the differential cross section and of the tensor and vector analyzing powers for the fragmentation of 4.5-GeV/c deuterons on beryllium in the reaction involving proton emission at an angle of 80 mrad

The invariant differential cross section, the tensor analyzing power Ayy, and the vector analyzing power Ay for the reaction 9Be(d, p)X are measured at an initial deuteron momentum of 4.5 GeV/c and a proton detection angle of about 80 mrad. The data obtained for the differential cross section are consistent with the results of measurements at 3.5 and 5.78 GeV/c and a proton emission angle of 2.5°. The values found for the tensor analyzing power Ayy are compared with similar data obtained previously for the deuteron-fragmentation process occurring on a carbon target at various values of the initial deuteron momentum and leading to proton emission at zero angle. The data on the differential cross section for the reaction 9Be(d, p)X can be satisfactorily described within the relativistic impulse approximation by using standard deuteron wave functions; however, the approach based on this conceptual framework proves to be inadequate in dealing with data on the tensor analyzing power. These results indicate that it is necessary either to change the method for describing the relativistic deuteron or to take into account additional mechanisms.