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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

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La formación de los sistemas binarios del cinturón de Kuiper a través de reacciones de intercambio

Yoko Funato¹, Junichiro Makino, Piet Hut

¹General Systems Studies, University of Tokyo, Komaba, Meguro-ku, Tokyo 153, Japan. funato@chianti.c.u-tokyo.ac.jp

|February 7, 2004

Resumen

Un nuevo mecanismo explica los objetos transneptunianos binarios (TNOs) extensos y excéntricos. Este proceso de formación implica una reacción de intercambio durante el crecimiento temprano de TNO, resolviendo un rompecabezas clave en la ciencia planetaria.

Área de la Ciencia:

Ciencias planetarias Ciencias planetarias.
La astronomía es la astronomía.
La astrofísica es la astrofísica.

Sus antecedentes:

Las observaciones muestran que una sorprendente fracción de los objetos transneptunianos (TNOs) son binarios.
Estos sistemas binarios poseen órbitas extensas y excéntricas, a diferencia de las predichas por las teorías de formación estándar.

Objetivo del estudio:

Proponer un nuevo mecanismo para la formación de TNO binarios con características observadas.
Para explicar la prevalencia de órbitas anchas y excéntricas en los sistemas binarios del cinturón de Kuiper.

Principales métodos:

Investigó un mecanismo de formación binaria basado en las inestabilidades gravitacionales en los discos protoplanetarios.
Modelado una reacción de intercambio que involucra un tercer cuerpo masivo y un binario preexistente.

Principales resultados:

El mecanismo propuesto produce con éxito TNOs binarios extensos y excéntricos.
Solo requiere el supuesto de la formación inicial de TNO a través de inestabilidades gravitacionales.

Conclusiones:

Este mecanismo de reacción de intercambio ofrece una explicación plausible para las propiedades únicas de los TNO binarios.
Concilia las observaciones con las teorías de formación sin suposiciones extremas sobre la distribución de tamaño de TNO.

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