arXiv subjects

T. Rindler-Daller

Publications and source records attributed to T. Rindler-Daller.

3 recordsLinked to original sources

arXiv2009

Analytical galactic models with mild stellar cusps

In the past two decades, it has been established by high-resolution observations of early-type galaxies that their nuclear surface brightness and corresponding stellar mass densities are characterized by cusps. In this paper, we present a new spherical analytical model family describing mild cuspy centres. We study isotropic and anisotropic models of Osipkov-Merritt type. It is shown that the associated distribution functions and intrinsic velocity dispersions can be represented analytically in a unified way in terms of hypergeometric series, allowing thus a straightforward comparison of these important global quantities for galaxies having underlying mass densities which may differ significantly in their degree of central cuspiness or radial falloff.

astro-ph.CO↗

arXiv2007

Rapidly Rotating Bose-Einstein Condensates in Homogeneous Traps

We extend the results of a previous paper on the Gross-Pitaevskii description of rotating Bose-Einstein condensates in two-dimensional traps to confining potentials of the form V(r) = r^s, $2<s <\infty$. Writing the coupling constant as $1/ε^2$ we study the limit $ε\to 0$. We derive rigorously the leading asymptotics of the ground state energy and the density profile when the rotation velocity Ωtends to infinity as a power of $1/ε$. The case of asymptotically homogeneous potentials is also discussed.

math-ph↗

arXiv2007

Rapidly Rotating Bose-Einstein Condensates in Strongly Anharmonic Traps

We study a rotating Bose-Einstein Condensate in a strongly anharmonic trap (flat trap with a finite radius) in the framework of 2D Gross-Pitaevskii theory. We write the coupling constant for the interactions between the gas atoms as $1/ε^2$ and we are interested in the limit $ε\to 0$ (TF limit) with the angular velocity $Ω$ depending on $ε$. We derive rigorously the leading asymptotics of the ground state energy and the density profile when $Ω$ tends to infinity as a power of $1/ε$. If $Ω(ε)=Ω_0/ε$ a ``hole'' (i.e., a region where the density becomes exponentially small as $1/ε\to\infty$) develops for $Ω_0$ above a certain critical value. If $Ω(ε)\gg 1/ε$ the hole essentially exhausts the container and a ``giant vortex'' develops with the density concentrated in a thin layer at the boundary. While we do not analyse the detailed vortex structure we prove that rotational symmetry is broken in the ground state for ${\rm const.}|\logε|<Ω(ε)\lesssim \mathrm{const.}/ε$.

math-ph↗