Theoretical predictions of experimental observables sensitive to the symmetry energy: Results of the SMF transport model

In the framework of mean-field based transport approaches, we discuss recent results concerning heavy ion reactions between charge asymmetric systems, from low up to intermediate energies. We focus on isospin sensitive observables, aiming at extracting information on the density dependence of the isovector part of the nuclear effective interaction and of the nuclear symmetry energy. For reactions close to the Coulomb barrier, we explore the structure of collective dipole oscillations, rather sensitive to the low-density behavior of the symmetry energy. In the Fermi energy regime, we investigate the interplay between dissipation mechanisms, fragmentation and isospin effects. At intermediate energies, where regions with higher density and momentum are reached, we discuss collective flows and their sensitivity to the momentum dependence of the isovector interaction channel, which determines the splitting of neutron and proton effective masses. Finally, we also discuss the isospin effect on the possible phase transition from nucleonic matter to quark matter. Results are critically reviewed, also trying to establish a link, when possible, with the outcome of other transport models.Comment: A contribution to the upcoming EPJA Special Volume on Nuclear Symmetry Energ

Facial Asymmetry Analysis Based on 3-D Dynamic Scans

Facial dysfunction is a fundamental symptom which often relates to many neurological illnesses, such as stroke, Bell’s palsy, Parkinson’s disease, etc. The current methods for detecting and assessing facial dysfunctions mainly rely on the trained practitioners which have significant limitations as they are often subjective. This paper presents a computer-based methodology of facial asymmetry analysis which aims for automatically detecting facial dysfunctions. The method is based on dynamic 3-D scans of human faces. The preliminary evaluation results testing on facial sequences from Hi4D-ADSIP database suggest that the proposed method is able to assist in the quantification and diagnosis of facial dysfunctions for neurological patients

Extracting current-induced spins: spin boundary conditions at narrow Hall contacts

We consider the possibility to extract spins that are generated by an electric current in a two-dimensional electron gas with Rashba-Dresselhaus spin-orbit interaction (R2DEG) in the Hall geometry. To this end, we discuss boundary conditions for the spin accumulations between a spin-orbit coupled region and contact without spin-orbit coupling, i.e. a normal two-dimensional electron gas (2DEG). We demonstrate that in contrast to contacts that extend along the whole sample, a spin accumulation can diffuse into the normal region through finite contacts and detected by e.g. ferromagnets. For an impedance-matched narrow contact the spin accumulation in the 2DEG is equal to the current induced spin accumulation in the bulk of R2DEG up to a geometry-dependent numerical factor.Comment: 18 pages, 7 figures, submitted to NJP focus issue on Spintronic

Maxwell demons in phase space

Although there is not a complete "proof" of the second law of thermo- dynamics based on microscopic dynamics, two properties of Hamiltonian systems have been used to prove the impossibility of work extraction from a single thermal reservoir: Liouville's theorem and the adiabatic invariance of the volume enclosed by an energy shell. In this paper we analyze these two properties in the Szilard engine and other systems related with the Maxwell demon. In particular, we recall that the enclosed volume is no longer an adiabatic invariant in non ergodic systems and explore the consequences of this on the second law.Comment: 14 pages, to appear in EPJS

Finite isospin density probe for conformality

A new method of employing an isospin chemical potential for QCD-like theories with different number of colors, number of fermion flavors, and in different fermion representations is proposed. The isospin chemical potential, which can be simulated on the lattice due to its positive definite determinant gives a means to probe both confining theories and IR conformal theories without adjusting the lattice spacing and size. As the quark mass is reduced, the isospin chemical potential provides an avenue to extract the chiral condensate in confining theories through the resulting pseudoscalar condensate. For IR conformal theories, the mass anomalous dimension can be extracted in the conformal window through "finite density" scaling since the isospin chemical potential is coupled to a conserved current. In both of these approaches, the isospin chemical potential can be continuously varied for each ensemble at comparable costs while maintaining the hierarchy between the lattice size and lattice spacing. In addition to exploring these methods, finite volume and lattice spacing effects are investigated.Comment: 18 pages, 3 figures, v3: typos corrected and discussions improved. Phys. Rev. D 85, 074503 (2012