arXiv subjects

Ariel Marom

Publications and source records attributed to Ariel Marom.

3 recordsLinked to original sources

arXiv2006

The Planets-Capture Model of V838 Monocerotis

The planets capture model for the eruption of V838 Mon is discussed. We used three methods to estimate the location where the planets were consumed. There is a nice consistency for the results of the three different methods, and we find that the typical stopping / slowing radius for the planets is about 1Ro. The three peaks in the optical light curve of V838 Mon are either explained by the swallowing of three planets at different radii or by three steps in the slowing down process of a single planet. We discuss the other models offered for the outburst of V838 Mon, and conclude that the binary merger model and the planet/s scenario seem to be the most promising. These two models have several similarities, and the main differences are the stellar evolutionary stage, and the mass of the accreted material. We show that the energy emitted in the V838 Mon event is consistent with the planets scenario. We suggest a few explanations for the trigger for the outburst and for the double structure of the optical peaks in the light curve of V838 Mon.

astro-ph↗

arXiv2003

A model of an expanding giant that swallowed planets for the eruption of V838 Monocerotis

In early 2002 V838 Monocerotis had an extraordinary outburst whose nature is still unclear. The optical light curve showed at least three peaks and imaging revealed a light echo around the object - evidence for a dust shell which was emitted several thousand years ago and now reflecting light from the eruption. Spectral analysis suggests that the object was relatively cold throughout the event, which was characterized by an expansion to extremely large radii. We show that the three peaks in the light curve have a similar shape and thus it seems likely that a certain phenomenon was three times repeated. Our suggestion that the outburst was caused by the expansion of a red giant, followed by the successive swallowing of three relatively massive planets in close orbits, supplies a simple explanation to all observed peculiarities of this intriguing object.

astro-ph↗

arXiv1997

An Adaptive Code For Radial Stellar Pulsations

We describe an implicit 1--D adaptive mesh hydrodynamics code that is specially tailored for radial stellar pulsations. In the Lagrangean limit the code reduces to the well tested Fraley scheme. The code has the useful feature that unwanted, long lasting transients can be avoided by smoothly switching on the adaptive mesh features starting from the Lagrangean code. Thus, a limit cycle pulsation that can readily be computed with the relaxation method of Stellingwerf will converge in a few tens of pulsation cycles when put into the adaptive mesh code. The code has been checked with two shock problems, viz Noh and Sedov, for which analytical solutions are known, and it has been found to be both accurate and stable. Superior results were obtained through the solution of the total energy (gravitational + kinetic + internal) equation rather than that of the internal energy only.

astro-ph↗