arXiv subjects

M. A. Gómez-Flechoso

Publications and source records attributed to M. A. Gómez-Flechoso.

3 recordsLinked to original sources

arXiv2004

The Shape of the Milky Way Halo and the Satellite Tidal Tails

The dwarf galaxies orbiting a main galaxy suffer strong tidal forces produced by its dark halo. As a consequence, substructures and tidal tails could appear in the satellites. These structures could give us information about the dark matter content of the main and the dwarf galaxies. The Milky Way satellites, because of their proximity, are a good sample to study the effects of the tidal forces. The shape of the Milky Way potential could be inferred from the observational data of the tidal tails of its satellites. The Sagittarius dwarf is one of the most interesting satellites as it presents a long tidal tail that covers a wide angle on the sky with a large variation of heliocentric distance along the stream.

astro-ph↗

arXiv1997

Dynamical Friction for Compound Bodies

In the framework of the fluctuation-dissipation approach to dynamical friction, we derive an expression giving the orbital energy exchange experienced by a compound body as it moves interacting with a non homogeneous discrete background. The body is assumed to be composed of particles endowed with a velocity spectrum and with a non homogeneous spatial distribution. The Chandrasekhar formula is recovered in the limit of a point-like satellite with zero velocity dispersion and infinite temperature moving through an homogeneous infinite medium. In this same limit, but dropping the zero satellite velocity dispersion ($σ_S$) condition, the orbital energy loss is found to be smaller than in the $σ_S=0$ case by a factor of up to an order of magnitude in some situations.

astro-ph↗

arXiv1994

Large Scale Morphological Segregation in Optically Selected Galaxy Redshift Catalogs

We present the results of an exhaustive analysis of the morphological segregation of galaxies in the CfA and SSRS catalogs through the scaling formalism. Morphological segregation between ellipticals and spirals has been detected at scales up to 15-20 h$^{-1}$ Mpc in the CfA catalog, and up to 20-30 h$^{-1}$ Mpc in the SSRS catalog. Moreover, it is present not only in the densest areas of the galaxy distribution, but also in zones of moderate density.

astro-ph↗