Stella is a popular system dynamics modeling tool, which helps to put together conceptual diagrams and converts them into numeric computer models. Although it can be very useful, especially in participatory modeling, it lacks the power and flexibility of a programming language. This paper presents the StellaR software which translates a Stella model into a model in R, an open source high level ...

We show that measurements of stellar proper motions in dwarf spheroidal galaxies provide a powerful probe of the nature of dark matter. Allowing for general dark matter density profiles and stellar velocity anisotropy profiles, we show that the log-slope of the dark matter profile at about twice the stellar core (King) radius can be measured to within ±0.2 when the proper motions of 200 stars a...

We examine whether massive binary black holes in spherically symmetric bulges of galaxies can achieve coalescence through the emission of gravitational radiation under the action of stellar dynamical processes alone. In particular, we address the importance of the Brownian motion of a binary’s center-of-mass to its continued interaction with stellar orbits that allows it to keep hardening: the ...

It has been an interesting question that why there are one-third of Kuiper Belt Objects (KBOs) trapped into the 3:2 resonance but, in contrast, only several KBOs are claimed to be associated with the 2:1 resonance. In a model proposed by Zhou et al. (2002), the stochastic outward migration of the Neptune could reduce the number of particles in the 2:1 resonance and thus the objects in the 3:2 r...

We estimate the mass of the central black hole in our Galaxy from stellar kinematical data published by Ghez et al. (1998) and Genzel et al. (2000). For this we develop a method, related to Merritt (1993), for non-parametrically reconstructing the mass profile and the stellar distribution function in the central region of the Galaxy from discrete kinematic data, including velocity errors. Model...

The NEMO-3 detector installed in the Modane Underground Laboratory (LSM, France) is running to search for neutrinoless double beta decay (ββ0ν) with an expected sensitivity for the effective Majorana neutrino mass down to 0.1 eV. New preliminary limits (90% CL), T 1/2 (ββ0ν) > 1.0 · 10 23 y (right-handed currents) and T 1/2 (ββ0ν) > 1.9 · 10 23 y (massive mechanism) were established analyzing 1...

In a composite system of gravitationally coupled stellar and gaseous discs, we perform linear stability analysis for axisymmetric coplanar perturbations using the two-fluid formalism. The background stellar and gaseous discs are taken to be scale-free with all physical variables varying as powers of cylindrical radius r with compatible exponents. The unstable modes set in as neutral modes or st...

Abstract Triangulum (M33) is a low-mass, relatively undisturbed spiral galaxy that offers new regime in which to test models of dynamical heating. In spite its proximity, M33's heating history has not yet been well-constrained. this work, we present the TREX Survey, largest stellar spectroscopic survey across disk M33. We kinematics as function age study past and ongoing measure line-of-sight v...