Unpolarized Deuterons Research Articles

EFFECT OF THE COULOMB INTERACTION TO THE PROCESSES OF INELASTIC DEUTERON SCATTERING ON NUCLEI AND THE STRUCTURE OF DEUTERON

The available experimental data on the interaction of polarized and unpolarized deuterons with a large deuteron momentum transfer require their theoretical description and interpretation. At the same time, further experimental studies require theoretical predictions in turn. In particular, there is a need to develop a theoretical model that makes it possible to smoothly connect available experimental data obtained at low-energy region, at which the nucleon-meson structure of the deuteron appears, with data obtained at high-energy region. The latter are related to the structure of the deuteron at small distances. Approaches based on the quark description of the deuteron structure are more adequate for their interpretation. The creation of such a model is an urgent task of modern nuclear physics, since it will allow one to reliably compare the asymptotic predictions of perturbative quantum chromodynamics and other quark approaches with the available experimental data. This will also make it possible to develop the theoretical approaches necessary for planning future experimental studies of elastic and inelastic deuteron scattering at high energies. In the framework of the Glauber–Sitenko model, the contribution of the Coulomb interaction to the reaction cross section A(d,p) at high energies and zero proton angle is calculated. The effect of taking into account the Coulomb interaction for the cross section in a wide inter-nuclear region is evaluated. The present calculations are compared with experiment. One fines that the Coulomb interaction gives a sizable contribution in the observables only at a peak, where the proton momentum is near half of the deuteron momentum in the lab. frame. But it does not change the results in the high momentum region, where quark effects should be taken into account.

Forward doubly-virtual Compton scattering off an unpolarized deuteron in pionless effective field theory

We calculate the forward unpolarised doubly-virtual Compton scattering (VVCS) off the deuteron in the framework of pionless effective field theory, up to next-to-next-to-next-to-leading order (N3LO) for the longitudinal and next-to-leading order (NLO) for the transverse amplitude. The charge elastic form factor of the deuteron, obtained from the residue of the longitudinal VVCS amplitude, is used to extract the value of the single unknown two-nucleon one-photon contact coupling that enters the longitudinal amplitude at N3LO. We also study the lowest spin-independent generalised polarisabilities of the deuteron. The calculated unpolarised VVCS amplitude provides a high-precision model-independent input for a future calculation of the two-photon-exchange correction to the Lamb shift of muonic deuterium.

Parity Violation in Proton—Deuteron Scattering

The effects of parity violation in the interaction of relativistic polarized protons and deuterons are discussed. Within Glauber's approach, estimates are obtained for P-odd asymmetries in the total and elastic scattering cross sections, in the deuteron dissociation cross section, and in the inelastic cross section with meson production in a final state. It is shown that, from the point of view of the magnitude of the P-odd effects, the interaction of polarized deuterons with unpolarized protons has an advantage over the interaction of polarized protons with unpolarized deuterons. A significant P-odd asymmetry was found in the dissociation channel of the polarized deuteron.

The differential cross section in deuteron-proton elastic scattering at 500, 750 and 900 MeV/nucleon

The results on the differential cross section of dp elastic scattering obtained at the Internal Target Station at the Nuclotron JINR at the energies of 500, 750 and 900MeV/nucleon are presented. The measurements have been performed using an unpolarized deuteron beam and polyethylene foil target. The data have been obtained in the angular range of $ 70^{\circ}$ - $ 120^{\circ}$ in the cms. The angular dependences of the data from the present experiment are compared with the world experimental data obtained at nearby energies as well as with the theoretical calculations performed within the relativistic multiple scattering theory. The behavior of the differential cross section at the fixed scattering angles covering the total cms energy region of $ \sqrt{s} = 3.1 -3.42$ GeV is in qualitative agreement with the s power-law dependence.

Dp breakup reaction investigation using polarized and unpolarized deuteron beam

Deuteron Spin Structure (DSS) collaboration program is aimed on few nucleon correlations investigation using unpolarized and polarized deuteron beam at intermediate energy range. Data of the dp breakup reaction have been obtained at energy range from 300 - 500 MeV of deuteron energy for various detector configurations in region where few nucleon correlations and relativistic effects can play significant role. Results are obtained in the form of S-curve and T20 and iT11 tensor analyzing powers in case of unpolarized and polarized data, respectively. Future plans on extracted deuteron beam of Nuclotron are concerned to tensor analyzing power T20 and spin correlation Cyy of 3He(d, p)4He reaction in the kinetic energy range between 1.0 and 1.75 GeV.

Source of polarized ions for the JINR accelerator complex

The JINR atomic beam type polarized ion source is described. Results of tests of the plasma ionizer with a storage cell and of tuning of high frequency transition units are presented. The source was installed in a linac injector hall of NUCLOTRON in May 2016. The source has been commissioned and used in the NUCLOTRON runs in 2016 and February – March 2017. Polarized and unpolarized deuteron beams were produced as well as polarized protons for acceleration in the NUCLOTRON. Polarized deuteron beam with pulsed current up to 2 mA has been produced. Deuteron beam polarization of 0.6-0.9 of theoretical values for different modes of high frequency transition units operation has been measured with the NUCLOTRON ring internal polarimeter for the accelerated deuteron and proton beams.

Investigation of reactions using polarized and unpolarized deuteron beam at Nuclotron: current status and perspectives

Deuteron induced reactions at intermediate energies are investigated at Internal Target Station (ITS) of Nuclotron. The dp elastic scattering data have been accumulated in the angular range (70° - 120°) in c.m from 0.3 to 2.0 GeV of deuteron energy. Part of the obtained results of differential cross sections and analyzing powers of dp elastic scattering are compared with theoretical predictions based on relativistic multi-scattering model. The dp breakup data are obtained with the detection of two outgoing protons at the angles of (19° - 54°) in laboratory frame at the deuteron energies from 0.3 to 0.5 GeV in various detector configurations. One of the tools to study spin structure of short range correlations is the measurements of the cross section, tensor analyzing power T 20 and spin correlation parameter Cy,y in the d 3 He → p (0°)4 He reaction at the energies between 1.0 and 1.75 GeV using polarized 3 He target and extracted polarized deuteron beam from new polarized ion source at Nuclotron. For this purposes the feasibility study has been performed. Proposed experiments on extracted deuteron beam of Nuclotron is aimed to investigate: non-nucleonic degrees of freedom and baryonic resonances properties in the d(A,d(0°))X and d(A,π -(0°))X reactions at different energies, non-nucleonic degrees of freedom via the measurements of the tensor Ayy and vector Ay analyzing powers in d(A,π -)X reaction and polarization properties of the baryonic resonances in the d(A,d)X reaction and others. First measurement of vector and tensor polarization of new polarized ion source has been performed in June-July of 2016y.

Contribution of three nucleon force investigated in deuteron-proton breakup reaction

The elastic scattering and deuteron breakup data were collected in the experiment performed at KVI (Groningen) with use of unpolarized deuteron beam with energy of 80 MeV per nucleon, impinging on hydrogen target. The procedure applied to determine total integrated luminosity is presented. The result will be used for normalization of the differential cross section for the deuteron-proton breakup reaction.

Possible measurements of the spin one observables in elastic dN, dd collisions at the NICA deuteron beams

The report shows the possibilities of studying the spin one observables in the elastic dN and dd interactions at the NICA collider of the VBLHEP JINR. The use of the colliding deuteron beams would allow us to carry out the measurements of the differential cross sections I0(dN, dd) of the elastic scattering of unpolarized deuterons and the differential cross sections Ipol(dN,dd) and the vector Ay(Ed,θ) and tensor Ayy(Ed,θ) and Axx(Ed.θ) analyzing powers in elastic collisions of the vector and tensor polarized deuterons. The planned luminosity of the colliding polarized deuteron beams will provide sufficiently high elastic events counting rate. The use of the colliding beams of the polarized deuterons for the spin one >dN and dd observables research has a number of significant advantages in comparison with the experiments with the “fixed” target. The angular acceptance of the collider detector covers the full solid angle 4π radians while the wide ranges of the energies of the dN, dd interactions and the 4-momentum transfer squared are available.

Experimental Investigation of Few-Nucleon Dynamics at Medium Energies

An experiment, with unpolarized deuteron beam of 160 MeV impinging on liquid hydrogen and liquid deuterium targets, was carried out using BINA detector at KVI, in Groningen, the Netherlands. Data were collected for the purpose of obtaining high precision differential cross-section for the deuteron break-up reaction. The elastic scattering data were also collected alongside. We present here the methods applied in analysis of data collected in the backward part of the detector.

Experimental data on the dp → ppn reaction at the deuteron energy of 300–500MeV obtained at ITS at Nuclotron

The experiment on dp non-mesonic breakup at Internal Target Station at Nuclotron is presented. Recent results on the study of the dp-breakup reaction with 300–500[Formula: see text]MeV unpolarized deuteron beam at Internal Target Station at Nuclotron are discussed. Selection procedure of useful events for the [Formula: see text] reaction with the registration of two protons is shown. Further scientific program with polarized and unpolarized deuterons is discussed.

Energy dependence of the parity-violating asymmetry of circularly polarized photons indγ⃗→npin pionless effective field theory

We calculate the energy dependence of the asymmetry in the cross sections for circularly polarized photons on an unpolarized deuteron target in $d\vec{\gamma} \to np$ in pionless effective field theory. By matching the parity-violating low-energy constants to different sets of corresponding model parameters we obtain estimates for the asymmetry. In addition we calculate two possible figures of merit for the asymmetry in order to assess the preferred photon energy at which to perform a possible future experiment at a high-intensity photon source.

On the beam spin asymmetries of electroproduction of charged hadrons off the nucleon targets

We study the beam single-spin asymmetries \(A_{\mathrm{LU}}^{\sin \phi _h}\) for charged hadrons produced in semi-inclusive deep-inelastic scattering processes, by considering the \(e H_1^\perp \) term and the \(g^\perp D_1\) term simultaneously. Besides the asymmetries for charged pions, for the first time we present the analysis on the asymmetries in the production of charged kaons, protons, and antiprotons by longitudinally polarized leptons scattered off unpolarized proton and deuteron targets. In our calculation we use two sets of transverse momentum dependent distributions \(g^\perp (x,\varvec{k}_T^2)\) and \(e(x,\varvec{k}_T^2)\) calculated from two different spectator models, and we compare the numerical results with the preliminary data recently obtained by the HERMES Collaboration. We also predict the beam spin asymmetries for \(\pi ^\pm \), \(K^\pm \), \(p/\bar{p}\) electroproduction in semi-inclusive deep-inelastic scattering of 12 GeV polarized electrons from unpolarized proton and deuteron targets.

Charged hadron lepto-production off unpolarized protons and deuterons at HERMES

The HERMES collaboration has measured charge-separated pion and kaon multiplicities in semi-inclusive deep-inelastic scattering using a 27.6 GeV electron or positron beam scattering off a hydrogen or deuterium target. The results are presented as functions of the Bjorken variable x B , the negative squared four-momentum transfer Q 2 , a hadron fractional energy z and the hadron's transverse momentum. These data will be very useful to understand the quark-fragmentation process in deep-inelastic hadron electro-production and will serve as crucial input in the understanding of charge and flavour separated fragmentation functions. Furthermore, it provides important information on the transverse-momentum dependence of hadron production.

Experimental Investigation of the Few-Nucleon Dynamics in Deuteron-Deuteron Collision at 160 MeV

An experiment, with unpolarized deuteron beam of 160 MeV impinging on liquid deuterium target, was carried out using BINA detector at KVI, in Groningen, the Netherlands. Data were collected for the purpose of obtaining high precision differential cross-section for the deuteron break-up reaction. The elastic scattering data were also col- lected alongside for the purpose of cross-section normalization. We present here a sample of the un-normalised cross-section for the three-body final state (dd→dpn) reaction.

Experiment on the Study of the [formula omitted] Reaction at 300–500 Mev of the Deuteron Energy at ITS at Nuclotron

The experiment on dp non-mesonic breakup at Internal Target Station at Nuclotron-M is presented. The first results on the study of the dp-breakup reaction with 300-500 MeV unpolarized deuteron beam are discussed. Selection procedure of useful events for the dp→ppn reaction with the registration of two protons is shown.

Three- and Four-nucleon Dynamics at Intermediate Energies

I. Skwira-Chalot Faculty of Physics, University of Warsaw, Hoza 69, 00-681 Warszawa, Poland (Received August 6, 2013) An experiment, with unpolarized deuteron beam of 160 MeV impinging on liquid hydrogen and liquid deuterium targets, was carried out using BINA detector at KVI in Groningen, the Netherlands. Data were collected for the purpose of obtaining high precision differential cross sections of break-up channels in dp and dd collisions. The elastic scattering data were also collected alongside for the purpose of cross-section normalization. A brief description of the experiment and the data analysis as well as some preliminary results are presented.

The study of the [formula omitted] reaction at 500 MeV of the deuteron energy at ITS Nuclotron

The experiment on dp non-mesonic breakup at Internal Target Station at Nuclotron-M is presented. The first results on the study of the dp-breakup reaction with 500 MeV unpolarized deuteron beam are discussed. Selection procedure of useful events for the d p → p p n reaction with the registration of two protons is shown.

Resonance-like production of tensor polarization in the interaction of an unpolarized deuteron beam with graphite targets

As shown in a recent paper, an initially unpolarized beam of deuterons can acquire appreciable tensor polarization by traversing a graphite foil. Here those results are presented which result when the earlier linear fits to the measured data are replaced by quadratic fits, taking into account slight non-linearities. The parameters of the fit to the energy dependence of the tensor polarization are discussed. Measured asymmetries confirm the azimuthal symmetry of the beam behind the targets. The values of pzz, achievable with graphite foils, are discussed.

On the possibility to measure the imaginary part of the spin-dependent amplitude of zero-angle coherent elastic scattering in a spin-filter experiment with an unpolarized proton beam interacting with a polarized deuterium target

As deuterons pass through an unpolarized target, there appear the phenomena of spin rotation (oscillation) and spin dichroism of deuterons; both phenomena are the manifestation of the deuteron birefringence effect. The magnitude of the effect is determined by the refractive index of deuterons in matter, which depends on the spin-dependent part d1 of the amplitude of zero-angle coherent elastic scattering of the deuteron by the nucleus. Spin dichroism is determined by the imaginary part of this amplitude, and in view of the optical theorem, by the total scattering cross-section, which is different for different spin states of the deuteron. The phenomenon of spin dichroism of deuterons results in the fact that after passing through the target, the initially unpolarized deuteron beam acquires tensor polarization proportional to the difference in the total cross-sections of scattering of deuterons with different spin states by the nucleus. The stated difference was first measured for deuterons with energies up to 20 MeV, where the phenomenon of deuteron spin dichroism was experimentally revealed, and the deuteron tensor polarization was measured. The phenomenon of spin dichroism, i.e., the production of tensor polarization was also observed at high deuteron energy. In the present report we discuss the possibility that the imaginary part of the amplitude d1 of deuteron scattering by the proton may be determined experimentally by measuring the rate of the decrease in the intensity of an unpolarized proton beam in a storage ring as the beam passes through a tensor-polarized deuterium target.