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HOLE-HOLE INTERACTIONS AND THE PROPERTIES OF NUCLEAR MATTER

Description: Recently a number of authors have suggested modifications of the Brueckner theory of nuclear matter so as to include hole-hole interactions, as well as particle-particle interactions. Iwamoto has demonstrated that in a perturbation theory calculation the inclusion of hole-hole interaction makes no change in the ground-state energy through second order. The singular two-body potential between nucleons makes it difficult, however, to conclude anything about the contribution of these terms in nuclear matter. The formal similarity between the equation of Iwamoto and the equation for the energy gap in nuclear matter, coupled with the fact that the energy gap is very small at normal density, indicates that the effect of hole-hole interactions is probably only a very small change in the ground-state energy of nuclear matter. It is the point of this note to show that this conclusion is in fact correct, the demonstration proceeding by use of the separation method for evaluating the energy of nuclear matter.
Date: April 4, 1960
Creator: Moszkowski, S.A. & Sessler, A.M.
Partner: UNT Libraries Government Documents Department

HYPER-STRANGE HADRONIC MATTER

Description: The binding energy of hyper-strange matter in the hadronic phase is calculated as a function of strangeness fraction in the mean field approximation to a relativistic field theory of matter. This is compared to a calculation of Chin and Kerman for the quark phase.
Date: November 1, 1980
Creator: Glendenning, Norman K.
Partner: UNT Libraries Government Documents Department

Liquid and crystalline neutron matter

Description: From sixth Texas symposium on relativistic astrophysics; New York, New York, USA (18 Dec 1972). Results of calculations of the ground-state energies of liquid and crystalline neutron matter are presented. It is found that neutron matter will crystallize at a density near normal nuclear density. This results indicates that a large fraction of the interior of a neutron star consists of crystalline neutron matter. An intuitive physical discussion is given to illuminate this result. Furthermore, it is suggested that, contrary to the usual point of view, low-density matter should be regarded as a quantum liquid'' which is almost'' a quantum crystal''. (2 figures, 1 table) (auth)
Date: January 1, 1972
Creator: Nosanow, L H & Parish, L J
Partner: UNT Libraries Government Documents Department

Classical behavior in high temperature chromodynamics

Description: In searching for tools to describe physical systems consisting of hadronic matter at high temperature, it is worthwhile to consider the application of classical chromodynamics. Classical non-Abelian gauge theories have been extensively studied and continue to attract theoretical interest. However, the thrust of most work has been to consider classical dynamics as merely a guide to the quantum mechanical path integral. Attention has therefore focussed on particle-like field configurations or on topological structures which may be important in the presence of color confinement. Confinement in low-temperature QCD provides a substantial barrier to the use of any classical approximations. With color fields confined to isolated spatial regions, it is vey implausible that any classical approximation can be made for bulk hadronic matter. However, at temperatures above the postulated deconfining phase transition there are reasons to believe that classical physics would be a valid approximation. Statistical fluctuations at high temperature can dominate quantum fluctuations and it is possible that the behavior of a large system can be described by averaged fields which obey classical equations. The use of the classical approximation for the non-Abelian dynamics is discussed. (WHK)
Date: January 1, 1984
Creator: Sivers, D.
Partner: UNT Libraries Government Documents Department

Brueckner--Bethe Calculations of Nuclear Matter

Description: The ideas of the Brueckner--Bethe hole-line expansion are briefly outlined. Four practical tests of its validity are formulated. These tests are applied to recent numerical results for the central potential v/sub 2/ and the semirealistic potential v/sub 6/ (Reid), which contains a tensor force but no spin-orbit force. The results are consistent with the validity of the hole-line expansion. The Brueckner--Bethe results are also consistent, within uncertainties of order 3 MeV, with variational results. 34 references.
Date: 1978
Creator: Day, B. D.
Partner: UNT Libraries Government Documents Department

RHIC CRITICAL POINT SEARCH: ASSESSING STARs CAPABILITIES.

Description: In this report we discuss the capabilities and limitations of the STAR detector to search for signatures of the QCD critical point in a low energy scan at RHIC. We find that a RHIC low energy scan will cover a broad region of interest in the nuclear matter phase diagram and that the STAR detector--a detector designed to measure the quantities that will be of interest in this search--will provide new observables and improve on previous measurements in this energy range.
Date: July 3, 2006
Creator: SORENSEN,P.
Partner: UNT Libraries Government Documents Department

Hard probes of short-range nucleon-nucleon correlations

Description: The strong interaction of nucleons at short distances leads to a high-momentum component to the nuclear wave function, associated with short-range correlations between nucleons. These short-range, high-momentum structures in nuclei are one of the least well understood aspects of nuclear matter, relating to strength outside of the typical mean-field approaches to calculating the structure of nuclei. While it is difficult to study these short-range components, significant progress has been made over the last decade in determining how to cleanly isolate short-range correlations in nuclei. We have moved from asking if such structures exist, to mapping out their strength in nuclei and studying their microscopic structure. A combination of several different measurements, made possible by high-luminosity and high-energy accelerators, coupled with an improved understanding of the reaction mechanism issues involved in studying these structures, has led to significant progress, and provided significant new information on the nature of these small, highly-excited structures in nuclei. We review the general issues related to short-range correlations, survey recent experiments aimed at probing these short-range structures, and lay out future possibilities to further these studies.
Date: October 1, 2012
Creator: J. Arrington, D. W. Higinbotham, G. Rosner, M. Sargsian
Partner: UNT Libraries Government Documents Department

Relativistic Description of Few Body Systems

Description: In this talk, I will discuss how relativistic meson theory is developed and applied to the electromagnetic description of the two nuclei system.These techniques are being extended to the three body system and very similar methods have been applied to nuclear matter, but I will not review this work here.
Date: March 1, 1985
Creator: Gross, Franz
Partner: UNT Libraries Government Documents Department

Relativistic Effects in Nuclei

Description: In this talk, I will discuss how relativistic meson theory is developed and applied to the electromagnetic description of the two nucleon system.These techniques are being extended to the three body system, and very similar methods have been applied to nuclear matter, but I will not review this work here.Many of the experiments proposed for ELSA and CEBAF will test the ideas discussed here, but I will devote the bulk of my discussion to the theoretical ideas rather than experimental tests.
Date: October 1, 1984
Creator: Gross, Franz
Partner: UNT Libraries Government Documents Department

The nuclear matter problem

Description: We review the present statiis of the many-body theory of nuclear and pure neutron matter based on realistic models of nuclear forces, The current models of two- and three-nucleon interactions are discussed along with recent results obtained with the Brueckner and variatioual methods. New initiatives in the variational method and quantuni Monte Carlo nicthods to study pure neutron matter are described, and finally, the analytic behavior of the energy of piire neutron matter at low densities is cliscussed.
Date: January 1, 2002
Creator: Carlson, J. A. (Joseph A.); Cowell, S.; Morales, J.; Ravenhall, D. G. & Pandharipande, V. R. (Vijay R.)
Partner: UNT Libraries Government Documents Department

Strongly coupled fermions in nature and the laboratory

Description: We report on recent work on the equation of state and pairing gap of neutron matter and cold atomic systems. Results of quantum Monte Carlo calculations show that the equations of state are very similar. The neutron matter pairing gap at low densities is found to be very large but, except at the smallest densities, significantly suppressed relative to cold atoms. We also discuss recent attempts to measure and extract the pairing gap in the fully paired superfluid state at unitarity.
Date: January 1, 2008
Creator: Carlson, Joseph; Gezerlis, Alexandros & Reddy, Sanjay
Partner: UNT Libraries Government Documents Department

Crystalline structure in the confined-deconfined mixed phase: Neutron stars as an example

Description: We review the differences in first order phase transition of single and multi-component systems, and then discuss the crystalline structure expected to exist in the mixed confined deconfined phase of hadronic matter. The particular context of neutron stars is chosen for illustration. The qualitative results are general and apply for example to the vapor-liquid transition in subsaturated asymmetric nuclear matter.
Date: April 18, 1996
Creator: Glendenning, N.K.
Partner: UNT Libraries Government Documents Department

Studies of fluctuation processes in nuclear collisions. Progress report, March 1, 1995--March 31, 1996

Description: This progress report studies of fluctuation processes in nuclear collisions discusses the following topics: quantal effects on growth of instabilities in nuclear matter; collisional damping of giant resonances in a non-Markovian approach; and medium-modified interaction induced by fluctuations.
Date: March 1, 1996
Creator: Ayik, S.
Partner: UNT Libraries Government Documents Department

QCD sum rules and properties of baryons in nuclei

Description: The use of medium-energy experiments to constrain in-medium four-quark condensates, whose uncertainty is currently the most important problem inhibiting the use of QCD sum rules to study hadrons in nuclear matter, is discussed. A value for a particular linear combination of these condensates is extracted using results of an Isobar-Doorway model analysis of pion-nucleus scattering data and a QCD sum rule analysis of the mass of the {Delta}(1232) in nuclei. Extending the analysis to include higher-lying baryon resonances is possible with data from modem facilities.
Date: December 31, 1995
Creator: Johnson, M.B. & Kisslinger, L.S.
Partner: UNT Libraries Government Documents Department

Heavy ion physics at the Brookhaven alternating gradient synchrotron

Description: The collision of large nuclei at relativisitic energies is the only known mechanism for creating and studying the properties (equation-of-state, EOS) of extremely dense nuclear matter. At sufficiently high matter densities, one of the most exciting possibilities is the formation of a Quark Gluon Plasma (QGP). However, it is an extremely difficult task to determine the ultimate density achieved during these collisions due to the fleeting nature of the high density state (the lifetime of these states is typically a few times 10-24 ns). We must rely on detailed comparisons between experimental measurements and complex Monte Carlo simulations of the colliding nuclei in order to extract meaningful estimates of the nuclear matter EOS. Our approach has been to study the behavior of the spectator matter (those protons and neutrons which do not directly interact during the collision) to determine the dynamics of the high density state which must necessarily influence the spectator matter as it decays. This report summarizes some of the key results of our study.
Date: January 30, 1995
Creator: Sangster, T.C.
Partner: UNT Libraries Government Documents Department