Warm stellar matter with deconfinement: application to compact stars

We investigate the properties of mixed stars formed by hadronic and quark matter in $\beta$-equilibrium described by appropriate equations of state (EOS) in the framework of relativistic mean-field theory. We use the non- linear Walecka model for the hadron matter and the MIT Bag and the Nambu-Jona-Lasinio models for the quark matter. The phase transition to a deconfined quark phase is investigated. In particular, we study the dependence of the onset of a mixed phase and a pure quark phase on the hyperon couplings, quark model and properties of the hadronic model. We calculate the strangeness fraction with baryonic density for the different EOS. With the NJL model the strangeness content in the mixed phase decreases. The calculations were performed for T=0 and for finite temperatures in order to describe neutron and proto-neutron stars. The star properties are discussed. Both the Bag model and the NJL model predict a mixed phase in the interior of the star. Maximum allowed masses for proto-neutron stars are larger for the NJL model ($\sim 1.9$ M$_{\bigodot}$) than for the Bag model ($\sim 1.6$ M$_{\bigodot}$).Comment: RevTeX,14 figures, accepted to publication in Physical Review

A decade of graphene research: production, applications and outlook

Graphene research has accelerated exponentially since 2004 when graphene was isolated and characterized for the first time utilizing the ‘Scotch Tape’ method by Geim and Novoselov and given the reports of unique electronic properties that followed. The number of academic publications reporting the use of graphene was so substantial in 2013 that it equates to over 40 publications per day. With such an enormous interest in graphene it is imperative for both experts and the layman to keep up with both current graphene technology and the history of graphene technology. Consequently, this review addresses the latter point, with a primary focus upon disseminating graphene research with a more applicatory approach and the addition of our own personal graphene perspectives; the future outlook of graphene is also considered