Relativistic quantum motion of spin-0 particles under the influence of non-inertial effects in the cosmic string space-time

We study solutions for the Klein-Gordon equation with vector and scalar potentials of the Coulomb types under the influence of non-inertial effects in the space-time of topological defects. We also investigate a quantum particle described by the Klein-Gordon oscillator in the background space-time generated by a string. An important result obtained is that the non-inertial effects restrict the physical region of the space-time where the particle can be placed. In addition, we show that these potentials can form bound states for the relativistic wave equation equation in this kind of background.Comment: arXiv admin note: text overlap with arXiv:1608.0669

Klein-Gordon oscillator in a topologically nontrivial space-time

In this study, we analyze solutions of the wave equation for scalar particles in a space-time with nontrivial topology. Solutions for the Klein--Gordon oscillator are found considering two configurations of this space-time. In the first one, it is assumed the $S^{1}\times R^{3}$ space where the metric is written in the usual inertial frame of reference. In the second case, we consider a rotating reference frame adapted to the circle S1. We obtained compact expressions for the energy spectrum and for the particles wave functions in both configurations. Additionally, we show that the energy spectrum of the solution associated to the rotating system has an additional term that breaks the symmetry around $E = 0$

Ages and metallicities of star clusters: new calibrations and diagnostic diagrams from visible integrated spectra

We present homogeneous scales of ages and metallicities for star clusters from very young objects, through intermediate-age ones up to the oldest known clusters. All the selected clusters have integrated spectra in the visible range, as well as reliable determinations of their ages and metallicities. From these spectra equivalent widths (EWs) of KCaII, Gband(CH) and MgI metallic, and Hdelta, Hgamma and Hbeta Balmer lines have been measured homogeneously. The analysis of these EWs shows that the EW sums of the metallic and Balmer H lines, separately, are good indicators of cluster age for objects younger than 10 Gyr, and that the former is also sensitive to cluster metallicity for ages greater than 10 Gyr. We propose an iterative procedure for estimating cluster ages by employing two new diagnostic diagrams and age calibrations based on the above EW sums. For clusters older than 10 Gyr, we also provide a calibration to derive their overall metal contents.Comment: 9 pages, 4 figures, accepted by A&

Mass distribution and structural parameters of Small Magellanic Cloud star clusters

In this work, we estimate, for the first time, the total masses and mass function (MF) slopes of a sample of 29 young and intermediate-age Small Magellanic Cloud (SMC) clusters from CCD Washington photometry. We also derive age, interstellar reddening and structural parameters for most of the studied clusters by employing a statistical method to remove the unavoidable field star contamination. Only these 29 clusters out of 68 originally analysed cluster candidates present stellar overdensities and coherent distribution in their colour–magnitude diagrams compatible with the existence of a genuine star cluster. We employed simple stellar population models to derive general equations for estimating the cluster mass based only on its age and integrated light in the B, V, I, C and T1 filter. These equations were tested against mass values computed from luminosity functions, showing an excellent agreement. The sample contains clusters with ages between 60 Myr and 3 Gyr and masses between 300 and 3000 M ⊙ distributed between ∼0$$_{.}^{\circ}5 and ∼2° from the SMC optical centre. We determined MF slopes for 24 clusters, of which 19 have slopes compatible with that of Kroupa's initial mass function (α = 2.3 ± 0.7), considering the uncertainties. The remaining clusters – H86-188, H86-190, K47, K63 and NGC 242 – showed flatter MFs. Additionally, only clusters with masses lower than ∼1000 M ⊙ and flatter MF were found within ∼0$ $_{.}^{\circ}6 from the SMC rotational centre.Fil: Maia, F.F.S.. Universidade Federal do Minas Gerais; BrasilFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Santos Jr., João F. C.. Universidade Federal do Minas Gerais; Brasi

Analytical BPS Maxwell-Higgs vortices

We have established a prescription for the calculation of analytical vortex solutions in the context of generalized Maxwell-Higgs models whose overall dynamics is controlled by two positive functions of the scalar field. We have also determined a natural constraint between these functions and the Higgs potential allowing the existence of axially symmetric Bogomol'nyi-Prasad-Sommerfield (BPS) solutions possessing finite energy. Furthermore, when the generalizing functions are chosen suitably, the nonstandard BPS equations can be solved exactly. We have studied some examples, comparing them with the usual Abrikosov-Nielsen-Olesen (ANO) solution. The overall conclusion is that the analytical self-dual vortices are well-behaved in all relevant sectors, strongly supporting the generalized models they belong themselves. In particular, our results mimic well-known properties of the usual (numerical) configurations, as localized energy density, while contributing to the understanding of topological solitons and their description by means of analytical methods.Comment: 8 pages, 4 figure