The application of the Quark-Hadron Chiral Parity-Doublet Model to neutron star matter

The Quark-Hadron Chiral Parity-Doublet model (Q$\chi$P) is applied to calculate compact star properties in the presence of a deconfinement phase transition. Within this model, a consistent description of nuclear matter properties, chiral symmetry restoration, and a transition from hadronic to quark and gluonic degrees of freedom is possible within one unified approach. We find that the equation of state obtained is consistent with recent perturbative quantum chromodynamics (QCD) results and is able to accommodate observational constraints of massive and small neutron stars. Furthermore, we show that important features of the equation of state, such as the symmetry energy and its slope, are well within their observational constraints.Comment: 8 pages, 9 figures and 1 tabl

Large Scale Baryon Isocurvature Inhomogeneities

Big bang nucleosynthesis constraints on baryon isocurvature perturbations are determined. A simple model ignoring the effects of the scale of the perturbations is first reviewed. This model is then extended to test the claim that large amplitude perturbations will collapse, forming compact objects and preventing their baryons from contributing to the observed baryon density. It is found that baryon isocurvature perturbations are constrained to provide only a slight increase in the density of baryons in the universe over the standard homogeneous model. In particular it is found that models which rely on power laws and the random phase approximation for the power spectrum are incompatible with big bang nucleosynthesis unless an {\em ad hoc}, small scale cutoff is included.Comment: 11pages + 8figures, LaTeX (2.09), postscript figures available via anonymous ftp from oddjob.uchicago.edu:/ftp/ibbn/fig?.ps where ?=1-8 or via email from [email protected], Fermilab-Pub-94/???-A and UMN-TH-1307/9

Production of eta Mesons in Double Pomeron Exchange

We estimate the production cross sections for $\eta_c$ and $\eta_b$ mesons via pomeron-pomeron fusion in peripheral heavy-ion collisions. Total and elastic PP cross sections are calculated in an equivalent pomeron approximation.Comment: 9 pages, 3 Postscript figure

Note on SLE and logarithmic CFT

It is discussed how stochastic evolutions may be linked to logarithmic conformal field theory. This introduces an extension of the stochastic Loewner evolutions. Based on the existence of a logarithmic null vector in an indecomposable highest-weight module of the Virasoro algebra, the representation theory of the logarithmic conformal field theory is related to entities conserved in mean under the stochastic process.Comment: 10 pages, LaTeX, v2: version to be publishe

Design guidelines for use of adhesives and organic coatings in hybrid microcircuits

A study was conducted to investigate the reliability of organic adhesives in hybrid microcircuits. The objectives were twofold: (1) to identify and investigate problem areas that could result from the use of organic adhesives and (2) to develop evaluation tests to quantify the extent to which these problems occur for commercially available adhesives. Efforts were focused on electrically conductive adhesives. Also, a study was made to evaluate selected organic coatings for contamination protection for hybrid microcircuits

Holomorphic Parafermions in the Potts model and SLE

We analyse parafermionic operators in the Q-state Potts model from three different perspectives. First, we explicitly construct lattice holomorphic observables in the Fortuin-Kasteleyn representation, and point out some special simplifying features of the particular case Q=2 (Ising model). In particular, away from criticality, we find a lattice generalisation of the massive Majorana fermion equation. We also compare the parafermionic scaling dimensions with known results from CFT and Coulomb gas methods in the continuum. Finally, we show that expectation values of these parafermions correspond to local observables of the SLE process which is conjectured to describe the scaling limit of the Q-state Potts model.Comment: 18 pages. v2: references to related work clarified. v3: minor corrections, version accepted for publication in JSTA

From FAIR to RHIC, hyper clusters and an effective strange EoS for QCD

Two major aspects of strange particle physics at the upcoming FAIR and NICA facilities and the RHIC low energy scan will be discussed. A new distinct production mechanism for hypernuclei will be presented, namely the production abundances for hypernuclei from $\Lambda$'s absorbed in the spectator matter in peripheral heavy ion collisions. As strangeness is not uniformly distributed in the fireball of a heavy ion collision, the properties of the equation of state therefore depend on the local strangeness fraction. The same, inside neutron stars strangeness is not conserved and lattice studies on the properties of finite density QCD usually rely on an expansion of thermodynamic quantities at zero strange chemical potential, hence at non-zero strange-densities. We will therefore discuss recent investigations on the EoS of strange-QCD and present results from an effective EoS of QCD that includes the correct asymptotic degrees of freedom and a deconfinement and chiral phase transition.Comment: Talk given at the international conference on Strangeness in Quark Matter 2011 in Krako

The Effect of Acute Exercise on Mood Following a Cognitive Test Battery

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Rotating Neutron Stars in a Chiral SU(3) Model

We study the properties of rotating neutron stars within a generalized chiral SU(3)-flavor model. The influence of the rotation on the inner structure and the hyperon matter content of the star is discussed. We calculate the Kepler frequency and moments of inertia of the neutron star sequences. An estimate for the braking index of the associated pulsars is given.Comment: 14 pages, 9 figure