Understanding local dwarf spheroidals and their scaling relations under MOdified Newtonian Dynamics
Por:
Hernandez, X, Mendoza, S, Suarez, T, Bernal, T
Publicada:
1 may 2010
Resumen:
We use a specific form of the interpolation function in the MOND formalism, which optimally accounts for the internal structure of dwarf spheroidal (dSph) galaxies, to explore the consequences it has on the scaling relations seen in these systems. The particular form of the interpolation function we used leads to a law of gravity that does not degrade the good fit of the MOND proposal on galactic scales, and in fact, slightly improves the accordance with observations on dSph scales. This formalism yields a good description of gravitational phenomena without the need of invoking any still undetected and hypothetically dominant dark matter, in the weak field regime probed by local dSph galaxies. Isothermal equilibrium density profiles then yield projected surface density profiles for the local dSph galaxies in very good agreement with observational determinations, for values of the relevant parameters as inferred from recent observations of these Galactic satellites. The observed scaling
Filiaciones:
Hernandez, X:
Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico
Mendoza, S:
Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico
Suarez, T:
Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico
Bernal, T:
Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico
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