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Probing the high momentum component of the deuteron at high Q^2  [PDF]
W. U. Boeglin,Hall A Collaboration
Physics , 2011, DOI: 10.1103/PhysRevLett.107.262501
Abstract: The d(e,e'p) cross section at a momentum transfer of 3.5 (GeV/c)^2 was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle theta_nq and to extract missing momentum distributions for fixed values of theta_nq up to 0.55 GeV/c. In the region of 35 (deg) <= theta_nq <= 45 (deg) recent calculations, which predict that final state interactions are small, agree reasonably well with the experimental data. Therefore these experimental reduced cross sections provide direct access to the high momentum component of the deuteron momentum distribution in exclusive deuteron electro-disintegration.
Structure of the ^3He in Backward Elastic p ^3He-Scattering  [PDF]
Yu. N. Uzikov
Physics , 1998, DOI: 10.1016/S0375-9474(98)00565-X
Abstract: Backward elastic $p ^3He$-scattering at incident proton kinetic energies $T_p>1$ GeV is investigated in the framework of the np-pair transfer mechanism and triangular diagram of one-pion exchange with a subprocess $pd\to ^3He\pi^0$ using a realistic three-body wave function of the $^3He$ nucleus. It is found that the $np-$pair transfer mechanism dominates owing to a rich high momentum component of the $^3He$ wave function. We show that the experimental cross section of this process is defined mainly by the values of the Faddeev component of the $^3He$ wave function, $\phi ^{23}({\bf q}_{23}, {\bf p}_1)$, at high relative momenta $q_{23}> 0.6 GeV/c$ of the NN-pair in the $^1S_0$-state and at low spectator momenta $p_1\leq 0.1$ GeV/c. The spin-spin correlation parameter is calculated in the framework of the dominating mechanism for the case of polarized target and beam. Rescatterings in the initial and final states are taken into account. Comparison with the $pd\to dp$ process is performed.
Simultaneous Measurement of Torsional Oscillator and NMR of Very Dilute 3He in Solid 4He  [PDF]
Ryo Toda,Patryk Gumann,Kei Kosaka,Masatomo Kanemoto,Wakana Onoe,Yutaka Sasaki
Physics , 2010, DOI: 10.1103/PhysRevB.81.214515
Abstract: We have investigated the NMR properties of dilute 3He impurities in solid 4He contained in a torsional oscillator (TO) by the simultaneous measurement of the NMR and the torsional oscillator response of the so-called supersolid 4He. From measurements on samples with one hundred to a few hundred ppm of 3He, we have found three different states of 3He. The first is the homogeneously distributed isolated 3He atom in a solid matrix of 4He. The second is the 3He cluster in a homogeneous 4He matrix, which appears below the phase separation temperature of a solid mixture. The third is the 3He cluster in some nonuniform part of a 4He crystal. We find that 3He atoms contained in the third component remain in a nearby location even above the phase separation temperature. Based on the fact that even a ppm of 3He affects the supersolid response in a TO below and above the phase separation temperature, we propose that the nonuniform part of a crystal that holds the third type of 3He and thus has a higher local concentration of 3He plays an important role in the supersolid phenomenon in a TO.
Suzaku broad-band spectrum of 4U 1705-44: Probing the Reflection component in the hard state  [PDF]
T. Di Salvo,R. Iaria,M. Matranga,L. Burderi,A. D'Ai,E. Egron,A. Papitto,A. Riggio,N. R. Robba,Y. Ueda
Physics , 2015, DOI: 10.1093/mnras/stv443
Abstract: Iron emission lines at 6.4-6.97 keV, identified with Kalpha radiative transitions, are among the strongest discrete features in the X-ray band. These are one of the most powerful probes to infer the properties of the plasma in the innermost part of the accretion disk around a compact object. In this paper we present a recent Suzaku observation, 100-ks effective exposure, of the atoll source and X-ray burster 4U 1705-44, where we clearly detect signatures of a reflection component which is distorted by the high-velocity motion in the accretion disk. The reflection component consists of a broad iron line at about 6.4 keV and a Compton bump at high X-ray energies, around 20 keV. All these features are consistently fitted with a reflection model, and we find that in the hard state the smearing parameters are remarkably similar to those found in a previous XMM-Newton observation performed in the soft state. In particular, we find that the inner disk radius is Rin = 17 +/- 5 Rg (where Rg is the Gravitational radius, GM/c^2), the emissivity dependence from the disk radius is -2.5 +/- 0.5, the inclination angle with respect to the line of sight is i = 43 +/- 5 degrees, and the outer radius of the emitting region in the disk is Rout > 200 Rg. We note that the accretion disk does not appear to be truncated at large radii, although the source is in a hard state at about 3 % of the Eddington luminosity for a neutron star. We also find evidence of a broad emission line at low energies, at 3.03 +/- 0.03 keV, compatible with emission from mildly ionized Argon (Ar XVI-XVII). Argon transitions are not included in the self-consistent reflection models that we used and we therefore added an extra component to our model to fit this feature. The low energy line appears compatible with being smeared by the same inner disk parameters found for the reflection component.
Macroscopic parity violating effects and 3He-A  [PDF]
G. E. Volovik,A. Vilenkin
Physics , 1999, DOI: 10.1103/PhysRevD.62.025014
Abstract: We discuss parity violating effects in relativistic quantum theory and their analogues in effective field theory of superfluid 3He-A. A mixed axial-gravitational Chern-Simons term in the relativistic effective action and its condensed matter analog are responsible for the chiral fermion flux along the rotation axis of the heat bath in relativistic system and for the unusual Omega-odd dependence of the zero-temperature density of the normal component on the rotation velocity in 3He-A.
Domain Walls in Superfluid 3He-B  [PDF]
A. Vorontsov,J. A. Sauls
Physics , 2004, DOI: 10.1007/s10909-005-1564-0
Abstract: We consider domain walls between regions of superfluid 3He-B in which one component of the order parameter has the opposite sign in the two regions far from one another. We report calculations of the order parameter profile and the free energy for two types of domain wall, and discuss how these structures are relevant to superfluid 3He confined between two surfaces.
Backward Elastic p^3He-Scattering and High Momentum components of ^3He Wave Function  [PDF]
Yu. N. Uzikov
Physics , 1998, DOI: 10.1103/PhysRevC.58.36
Abstract: It is shown that owing to a dominance of $np-$pair transfer mechanism of backward elastic $p^3He$- scattering for incident proton kinetic energies $T_p>1$ GeV the cross section of this process is defined mainly by the values of the Faddeev component of the wave function of $^3He$ nucleus, $\phi ^{23}({\bf q}_{23}, {\bf p}_1)$, at high relative momenta $q_{23}> 0.6 GeV/c$ of the NN-pair in the $^1S_0-$ state and at low spectator momenta $p_1\sim 0-0.2$ GeV/c.
Heterogeneous adsorption potential of 3He in silica aerogel and its influence on magnetic relaxation of 3He  [PDF]
E. M. Alakshin,R. R. Gazizulin,A. V. Klochkov,V. V. Kuzmin,M. S. Tagirov,D. A. Tayurskii
Physics , 2010,
Abstract: Significant influence of aerogel surface heterogeneity on the processes of 3He nuclear magnetic relaxation at temperatures 1.5 - 4.2 K is discovered. This influence appears, for instance, in differences of 3He T1 relaxation times for small portion of 3He, adsorbed at different temperatures. Binding energy data of 3He on the surface of powder silica aerogel obtained experimentally and binding energy lies in the wide range. Adsorbed 3He molecules with binding energies 60-250 K play supreme role in processes of nuclear magnetic relaxation of gaseous and liquid 3He in aerogel.
Super Stability of Laminar Vortex Flow in Superfluid 3He-B  [PDF]
V. B. Eltsov,R. de Graaf,P. J. Heikkinen,J. J. Hosio,R. Hanninen,M. Krusius,V. S. L'vov
Physics , 2010, DOI: 10.1103/PhysRevLett.105.125301
Abstract: Vortex flow remains laminar up to large Reynolds numbers (Re~1000) in a cylinder filled with 3He-B. This is inferred from NMR measurements and numerical vortex filament calculations where we study the spin up and spin down responses of the superfluid component, after a sudden change in rotation velocity. In normal fluids and in superfluid 4He these responses are turbulent. In 3He-B the vortex core radius is much larger which reduces both surface pinning and vortex reconnections, the phenomena, which enhance vortex bending and the creation of turbulent tangles. Thus the origin for the greater stability of vortex flow in 3He-B is a quantum phenomenon. Only large flow perturbations are found to make the responses turbulent, such as the walls of a cubic container or the presence of invasive measuring probes inside the container.
Experiments with polarized 3He at MAMI  [PDF]
Daniela Rohe
Physics , 2005, DOI: 10.1140/epja/i2006-09-004-7
Abstract: Experiments with polarized 3He at MAMI have already a long tradition. The A3 collaboration started in 1993 with the aim to measure the electric form factor of the neutron. At this time MAMI was the second accelerator where experiments with 3He were possible. Some years before this pilot experiment the development of the apparatus to polarize 3He in Mainz started. There are two techniques which allow to polarize sufficient large quantities of 3He. Both techniques will be compared and the benefit of 3He for nuclear physics will be discussed. An review of the experiments done so far with 3He at MAMI will be given and the progress in the target development, the detector setup and the electron beam performance will be pointed out.
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