Maximum latent heat of neutron star matter without GR

We show how the specific latent heat is relevant to characterize the first-order phase transitions in neutron stars. Our current knowledge of this dynamical quantity strongly depends on the uncertainty bands of Chiral Perturbation Theory and of pQCD calculations and can be used to diagnose progress on the equation of state. We state what is known to be hadron-model independent and without feedback from neutron star observations and, therefore, they can be used to test General Relativity as well as theories beyond GR, such as modified gravity.

Coherent states associated with two-dimensional elliptic and hyperbolic equations

In this article it is shown that by performing Levi–Chivita-type transformations in the two-dimensional Helmholtz and Klein–Fock-type equations, it is possible to determine coherent states in a standard way. Moreover, if in the case of the Helmholtz elliptic equation the Levi–Civita transformation is realized by a complex quadratic map, then in the case of the Klein–Foсk-type equation it is realized by an analogue of such a map however defined for functions of a double variable. The coordinate and momentum representations of the coherent state are found. The purpose of constructing coherent states in the described manner is a further development of the hadron model proposed in [1; 2].

NUCLEAR MATTER AND NEUTRON STARS IN A QUARK-HADRON MODEL

One of the difficulties in describing chiral symmetry and deconfinement phase transitions in strongly interacting matter at high temperatures as well as at high densities stems from the fact that one has to deal with very different degrees of freedom on both sides of the phase transition. Hadrons exist at low temperatures/densities whereas quarks and gluons occur in the other extreme. Gluing two separate equations of state together will necessarily lead to first-order phase transitions (which are not expected, at least not at small densities and high temperatures). In order to remedy this problem a unified model of quarks and hadrons (the QH model) has been developed that integrates both degrees of freedom in an effective chiral flavor-SU(3) ansatz. Results for nuclear matter and neutron stars for the purely hadronic part of the theory and then results for excited matter and stars for the full QH model are presented. Various extensions of this approach are discussed.

Nucleon-Nucleon High-Energy Scattering

The high energy pn charge exchange and pp elastic scattering reactions are studied in an effective hadron model for the energy range of s ~ 50 to 400 GeV2. The main features of the observed differential cross section of the pn charge exchange reaction, the forward peak and the scaling behavior over the large energy range, are well reproduced by a combination of π-, ρ-exchange and a 4-Nucleon contact term. The latter acts as a background field which turns out to be naturally suppressed in elastic N N scattering but contributes significantly to the charge-exchange reaction.