Showing papers on "Nuclear matter published in 1973"
TL;DR: An extremely simple form for the energy density of a nuclear many-body system derived from the two-body nucleon-nucleon interaction was used to determine the ground state configuration of matter at sub-nuclear density.
674 citations
TL;DR: In this paper, the relationship between geometrical properties of leptodermous distributions and optical-model potential wells was investigated and it was found that nuclear sizes imply a density for neutral symmetric nuclear matter corresponding to r0 = 1.16 fm (krmf = 1,31 fm−1) and that the densities and potentials can be related to each other by means of a saturating two-body interac1tion.
198 citations
TL;DR: In this article, O Sjoberg et al. showed that the discrepancy between the calculated Landau parameters and the experimental ones probably arise from neglect of the exchange of two and more spin fluctuations.
185 citations
TL;DR: A phenomenologieal local nucleon-nucleon potential has been constructed satisfying the following criteria: a high-quality fit to two-body bound state and scattering data up to 350 MeV; the amplitudes of all components are weak in the sense that perturbation theory in nuclear matter converges rapidly; the tensor force in the triplet even state is much weaker than in other potential models as discussed by the authors.
157 citations
TL;DR: In this article, the effective matrix elements which appear in pre-equilibrium calculations in the rate expressions for the residual two-body interactions have been evaluated from analyses of emitted particle energy spectra.
112 citations
TL;DR: In this paper, the Brueckner-Bethe theory was applied to normal Fermi liquids and the quasiparticle interaction and physical quantities related to this were calculated.
110 citations
TL;DR: In this article, it is suggested that very hot and dense nuclear matter may be formed in a transient state in "head-on" collisions of very energetic heavy ions with medium and heavy nuclei.
Abstract: It is suggested that very hot and dense nuclear matter may be formed in a transient state in "head-on" collisions of very energetic heavy ions with medium and heavy nuclei. A study of the particles emitted in these collisions should give clues as to the nature of dense hot nuclear matter. Some simple models regarding the effects of meson and ${N}^{*}$ production on the properties of dense hot nuclear matter are discussed.
97 citations
TL;DR: In this paper, the importance of α-clustering effects in the interior region of heavy nuclei is estimated by studying the existence of such phenomena in infinite nuclear matter assuming a crystalline type of structure where each lattice site is occupied by an α-particle.
75 citations
TL;DR: Appelquist and Quinn as discussed by the authors proposed a general unitarity program in the unitarity gauge, and the execution of this program was carried out by T. Appelquist, H. Quinn, and Y.-P Yao.
Abstract: *Work supported in part by the U. S. Atomic Energy Commission. The execution of this program in the unitarity gauge has been carried out by T. Appelquist and H. Quinn (private communication) . Y.-P. Yao, Phys. Rev. D 7, 1647 (1973). Notations and metric used in this note are the same as those in this reference. 3G. 't Hooft, Nucl. Phys. B33, 173 (1971), B35, 167 (1971); B. W. Lee, Phys. Rev. D 5, 823 (1972); B. W. Lee and J. Zinn-Justin, ibid. 5, 3121 (1972); 5, 3137 (1972); 5, 3155 (1972); E. S. Fradkin and I. V. Tyutin, P. N. Lebedev Physical Institute Report No. N55, 1972 (unpublished) . 4For example, A. A. Slavnov, Kiev report, 1971 (unpublished). ~A somewhat restricted class of gauges with K = (m has been considered by K. Fujikawa, B. W. Lee, and A. I. Sanda, Phys. Rev. D 6, 2923 (1972). T. D. Lee and C. N. Yang, Phys. Rev. 128, 885 (1962). ~E. C. G. Stueckelberg, Helv. Phys. Acta 11, 299 (1938); R. P. Feynman, Acta Phys. Polon. 24, 697 (1963); 't Hooft (see Ref. 3). BIn fact, we do not expect them to be satisfied because of the Adler-BellJackiw-type anomaly. See D. Gross and R. Jackiw, Phys. Rev. D 6, 477 (1972); C. Bouchiat, J. Iliopoulos, and Ph. Meyer, Phys. Lett. 38B, 519 (1972). ~T. Appelquist and H. Quinn, Phys. Letters 398, 229 (1972).
71 citations
TL;DR: The π-meson spectrum in nuclear matter for N = Z is obtained in this article, where it is shown that there are two branches of the meson spectrum and that at a density which is less than the nuclear one, an instability occurs, leading to a phase transition which changes the energy of the ground state of the nucleus.
50 citations
TL;DR: In this article, it was shown that the off-shell p-wave attraction of pions and nucleons lies, at least in the region of low momenta, completely in the domain of the DELTA -isobars.
TL;DR: The requirement of unitarity, together with the theory of the refractive index, puts a limit on the wave number of a pion (of given energy) in nuclear matter.
Abstract: The requirement of unitarity, together with the theory of the refractive index, puts a limit on the wave number of a pion (of given energy) in nuclear matter (of given density). A paradox in the conventional theory of pion scattering by complex nuclei is thereby avoided.
TL;DR: In this article, the effect of the polarization of the medium around a quasiparticle was investigated and the main result was that the introduction of a model space does not appreciably change the quasipparticle's effective mass.
TL;DR: In this paper, it was shown that in nuclear matter at Z = N for density n, there are two phase transitions: one corresponds to π0 condensation and second to the electrically neutral π+, π- condensation.
TL;DR: In this article, an expression for the energy dissipation during nuclear fission (or heavy-ion) processes has been derived in the first-order viscosity approximation, based on a modified algebraic parameterization of the nuclear shape.
TL;DR: In this article, the three main corrections to the binding energy of nuclear matter that involve the Δ (1236) were calculated with exchange effects and realistic correlation functions, and it was found that their net effect at K F = 1.36 fm −1 is small, but that their K F dependence has a considerable effect on the saturation density.
TL;DR: In this paper, the Λ particle binding energy in nuclear matter is calculated with a phenomenological separable ΛN-ΣN potential matrix and with a separable NN potential.
TL;DR: In this paper, the P-wave pion-nucleon attraction is shown to overcome the free pion energy at some critical density ρc and wave vector kc.
Abstract: It has been suggested1–3 that dense nuclear matter might achieve a lower energy by creating a macroscopic number of negative pions condensed in a small region of k space. This comes about because the P-wave pion-nucleon attraction (basically proportional to σ.k) is able to overcome the free pion energy at some critical density ρc and wave vector kc. Predictions for ρc lie in the range 0.25 to 1.0 nucleons fm−3 and kc is estimated to be 1 to 3 in units of mπc/h∼0.7 fm−1, which we use here.
TL;DR: In this article, a review of nuclear structure covers early developments, the nucleus as a quantal many-body system, the interplay of shell structure and nuclear deformations, interaction of nuclear matter in bulk (heavy ion reactions), elementary modes of excitation in a unified description of nuclear dynamics, the fine-grain structure of nuclear Matter (high energy probes), and statistics of quantal states for the compound nucleus.
Abstract: The review of nuclear structure covers early developments, the nucleus as a quantal many-body system, the interplay of shell structure and nuclear deformations, interaction of nuclear matter in bulk (heavy ion reactions), elementary modes of excitation in a unified description of nuclear dynamics, the fine-grain structure of nuclear matter (high energy probes), and statistics of quantal states for the compound nucleus. Also covered are the strength function for direct interactions, isobaric analog resonance, collective modes in the nuclear pair field (two-particle transfer reactions) rotational spectra, generalized rotational motion, phase transitions induced by rotational perturbation in the Yrast region, and connections to other fields. (auth) reduction of isospin mixing in filled subshells was indicated. (2 tables) (tr- auth)
TL;DR: Using a folding method in which the spherical and non-spherical components of the optical potential are calculated consistently, it is shown that it is possible to get a simultaneous fit to the elastic and inelastic scattering of 104 MeV α-particles from 24 Mg.
TL;DR: In this article, the possibility of negative-pion condensation in superdense nuclear matter is shown to be based on an incorrect formalism, and some problems are enumerated which must be solved before it is known which, if either, of the phenomena can occur.
Abstract: Recent remarks on the possibility of negative-pion condensation in superdense nuclear matter are shown to be based on an incorrect formalism. The possibilities of ${\ensuremath{\pi}}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{0}$ condensation are compared and some problems are enumerated which must be solved before it is known which, if either, of the phenomena can occur.
TL;DR: In this paper, the Hartree-Fock type has been used to determine an effective interaction having no hard core, and giving the correct binding energy and density of nuclear matter.
TL;DR: In this paper, the specific energy of the nuclear matter in the presence of the pi -condensate is found, i.e., in the region of model applicability there are no phase transitions of both the first and the second order.
TL;DR: In this article, the particle-hole Green function is used to handle the nucleon-nucleon tensor potential in order to investigate both the ring correlation energy and collective excitations in nuclear matter.
TL;DR: The model of nuclear matter proposed by Gomes, Walecka and Weisskopt (1958) is generalized to finite temperatures including interacting Fermi particle aspects as mentioned in this paper.
TL;DR: In this article, extensive results, obtained in the G -matrix approximation for a wide range of central ΛN Yukawa potentials both with hard cores (HC) and soft repulsive cores, are presented for the Λ well depth (binding energy of a Λ-particle in nuclear matter) and related quantities.