PaperPanorama
FAQ

Nuclear Theory·nucl-th

Friday·January 23, 2015

10 papers—5 primary·5 cross-listed

All10Primary5Cross-lists5
  1. 06

    Modern Studies of the Deuteron: from the Lab Frame to the Light Front

    Werner Boeglin🇺🇸 · Misak Sargsian🇺🇸

    We review the recent progress made in studies of deuteron structure at small internucleon distances. This progress is largely facilitated by the new generation of experiments in deuteron electrodisintegration carried out at unprecedentedly high momentum transfer. The theoretical analysis of these data confirms the onset of the high energy eikonal regime in the scattering process which allows one to separate long range nuclear effects from the effects genuinely related to the short distance structure of the deuteron. Our conclusion is that for the first time the deuteron is probed at relative momenta beyond 300 MeV/c without dominating long range effects. As a result, at these large nucleon momenta the cross section is sensitive to the nuclear dynamics at sub-fermi distances. Due to large internal momenta involved we are dealing with the relativistic bound state that is best described by the light-cone momentum distribution of nucleons in the deuteron. We present the first attempt of extracting the deuteron light-cone momentum distribution function from data and discuss the importance of this quantity for studies of QCD structure of the bound nucleon in deep inelastic scattering off the deuteron. We conclude the review giving an outlook of the next generation of high energy experiments which will extend our reach to much smaller distances in the deuteron.

    ↳ nucl-exhep-exhep-phnucl-thIJMPE(2015)·33 citations
  2. 07

    Skyrmions with low binding energies

    Mike Gillard🇬🇧 · Derek Harland🇬🇧 · Martin Speight🇬🇧

    Nuclear binding energies are investigated in two variants of the Skyrme model: the first replaces the usual Skyrme term with a term that is sixth order in derivatives, and the second includes a potential that is quartic in the pion fields. Solitons in the first model are shown to deviate significantly from ansätze previously assumed in the literature. The binding energies obtained in both models are lower than those obtained from the standard Skyrme model, and those obtained in the second model are close to the experimental values.

    ↳ hep-thnucl-thNPB(2015)·95 citations
  3. 08

    Azimuthal harmonics of color fields in a high energy nucleus

    T. Lappi🇫🇮

    Recent experimental results have revealed a surprisingly rich structure of multiparticle azimuthal correlations in high energy proton-nucleus collisions. Final state collective effects can be responsible for many of the observed effects, but it has recently been argued that a part of these correlations are present already in the wavefunctions of the colliding particles. We evaluate the momentum space 2-particle cumulant azimuthal anisotropy coefficients v_n{2}, n=2,3,4 from fundamental representation Wilson line distributions describing the high energy nucleus. These would correspond to the flow coefficients in very forward proton nucleus scattering. We find significant differences beteen Wilson lines from the MV model and from JIMWLK evolution. The magnitude and transverse momentum dependence of the v_n{2} values suggest that the fluctuations present in the initial fields are a significant contribution to the observed anisotropies.

    ↳ hep-phnucl-thPLB(2015)·56 citations
  4. 09

    Rotating Bose-Einstein condensates: Closing the gap between exact and mean-field solutions

    J. C. Cremon · A. D. Jackson · E. Ö. Karabulut · G. M. Kavoulakis · B. R. Mottelson · S. M. Reimann

    When a Bose-Einstein condensed cloud of atoms is given some angular momentum, it forms vortices arranged in structures with a discrete rotational symmetry. For these vortex states, the Hilbert space of the exact solution separates into a "primary" space related to the mean-field Gross-Pitaevskii solution and a "complementary" space including the corrections beyond mean-field. Considering a weakly-interacting Bose-Einstein condensate of harmonically-trapped atoms, we demonstrate how this separation can be used to close the conceptual gap between exact solutions for systems with only a few atoms and the thermodynamic limit for which the mean-field is the correct leading-order approximation. Although we illustrate this approach for the case of weak interactions, it is expected to be more generally valid.

    ↳ cond-mat.quant-gasnucl-thPRA(2015)·7 citations
  5. 10

    Phase structure of mass- and spin-imbalanced unitary Fermi gases

    Dietrich Roscher🇩🇪 · Jens Braun🇩🇪 · Joaquín E. Drut🇺🇸

    We study the phase diagram of mass- and spin-imbalanced unitary Fermi gases, in search for the emergence of spatially inhomogeneous phases. To account for fluctuation effects beyond the mean-field approximation, we employ renormalization group techniques. We thus obtain estimates for critical values of the temperature, mass and spin imbalance, above which the system is in the normal phase. In the unpolarized, equal-mass limit, our result for the critical temperature is in accordance with state-of-the-art Monte Carlo calculations. In addition, we estimate the location of regions in the phase diagram where inhomogeneous phases are likely to exist. We show that an intriguing relation exists between the general structure of the many-body phase diagram and the binding energies of the underlying two-body bound-state problem, which further supports our findings. Our results suggest that inhomogeneous condensates form for mass ratios of the spin-down and spin-up fermions greater than three. The extent of the inhomogeneous phase in parameter space increases with increasing mass imbalance.

    ↳ cond-mat.quant-gashep-phnucl-thPRA(2015)·44 citations

Affiliations

first authorsco-authorsvia INSPIRE