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Adolfo López Mateos, Mexico

Sanchez-Salcedo F.J.,National Autonomous University of Mexico | Flynn C.,University of Sydney | Flynn C.,University of Turku | Hidalgo-Gamez A.M.,Escuela Superior de Fisica y Matemticas
Astrophysical Journal Letters | Year: 2011

Estimates of the dynamical surface mass density at the solar Galactocentric distance are commonly derived assuming that the disk is in vertical equilibrium with the Galactic potential. This assumption has recently been called into question, based on the claim that the ratio between the kinetic and the gravitational energy in such solutions is a factor of three larger than required if virial equilibrium is to hold. Here we show that this ratio between energies was overestimated and that the disk solutions are likely to be in virial equilibrium after all. We additionally demonstrate, using one-dimensional numerical simulations, that the disks are indeed in equilibrium. Hence, given the uncertainties, we find no reason to cast doubt on the steady-state solutions which are traditionally used to measure the matter density of the disk. © 2011. The American Astronomical Society. All rights reserved. Source


Rodriguez-Gonzalez A.,National Autonomous University of Mexico | Velazquez P.F.,National Autonomous University of Mexico | Rosado M.,National Autonomous University of Mexico | Esquivel A.,National Autonomous University of Mexico | And 2 more authors.
Astrophysical Journal | Year: 2011

The morphology, dynamics, and thermal X-ray emission of the superbubble N70 are studied by means of three-dimensional hydrodynamic simulations carried out with the YGUAZÚ-A code. We consider three possible scenarios: the superbubble being the product of a single supernova remnant, of the stellar winds from an OB association, or of the joint action of stellar winds and a supernova (SN) event. Our results show that, in spite of the fact that all scenarios produce bubbles with the observed physical size, only those in which the bubble is driven by stellar winds and an SN event successfully explain the general morphology, dynamics, and X-ray luminosity of N70. Our models predict temperatures in excess of 108 K at the interior of the superbubble; however, the density is too low and thermal X-ray emission above 2 keV is too faint to be detected. © 2011. The American Astronomical Society. All rights reserved.. Source


Repetto P.,National Autonomous University of Mexico | Rosado M.,National Autonomous University of Mexico | Gabbasov R.,National Autonomous University of Mexico | Fuentes-Carrera I.,Escuela Superior de Fisica y Matemticas
Astronomical Journal | Year: 2010

In this work, we present scanning Fabry-Perot (FP) Hα observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA FP interferometer. We derived velocity fields and rotation curves for both galaxies. For NGC 5278 we also obtained the residual velocity map to investigate the non-circular motions, and estimated its mass by fitting the rotation curve with disk+halo components. We test three different types of halos (pseudo-isothermal, Hernquist, and Navarro-Frenk-White) and obtain satisfactory fits to the rotation curve for all profiles. The amount of dark matter required by the pseudo-isothermal profile is about 10 times smaller than that for the other two halo distributions. Finally, our kinematical results together with the analysis of dust lane distribution and of surface brightness profiles along the minor axis allowed us to determine univocally that both components of the interacting pair are trailing spirals. © 2010. The American Astronomical Society. Source


Qiang W.-C.,Xian University of Architecture and Technology | Dong S.-H.,Escuela Superior de Fisica y Matemticas
EPL | Year: 2010

We find a proper quantization rule, ∫xA xBk(x)dx- ∫x0A x0Bk0(x)dx=nπ, where n is the number of the nodes of wave function ψ(x). By this rule the energy spectra of a solvable system can be determined from its ground-state energy only. Particularly, we study three solvable quantum systems - modified Rosen-Morse potential, symmetric trigonometric Rosen-Morse potential and Manning-Rosen potential in D dimensions - with the proper quantization rule, and show that the previous complicated and tedious calculations can be greatly simplified. This proper quantization rule applies to any exactly solvable potential, and one can easily obtain its energy spectra with the rule. © 2010 EPLA. Source


Font J.,Institute of Astrophysics of Canarias | Font J.,University of La Laguna | Beckman J.E.,Institute of Astrophysics of Canarias | Beckman J.E.,University of La Laguna | And 14 more authors.
Astrophysical Journal Letters | Year: 2011

Using velocity tagging we have detected hydrogen from NGC 5426 falling onto its interacting partner NGC 5427. Our observations, with the GHaFaS Fabry-Perot spectrometer, produced maps of the two galaxies in Hα surface brightness and radial velocity. We found emission with the range of velocities associated with NGC 5426 along lines of sight apparently emanating from NGC 5427, superposed on the velocity map of the latter. After excluding instrumental effects we assign the anomalous emission to gas pulled from NGC 5426 during its passage close to NGC 5427. Its distribution, more intense between the arms and just outside the disk of NGC 5427, and weak, or absent, in the arms, suggests that the infalling gas is behind the disk, ionized by Lyman continuum photons escaping from NGC 5427. Modeling this, we estimate the distances of these gas clouds behind the plane: a few hundred parsecs to a few kiloparsecs. We also estimate the mass of the infalling (ionized plus neutral) gas, finding an infall rate of 10 M ∞ per year, consistent with the high measured star formation rate across the disk of NGC 5427 and with the detected circumnuclear galactic wind. © 2011. The American Astronomical Society. All rights reserved. Source

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