On the Erigone family and the $z_2$ secular resonance

Abstract

The Erigone family is a C-type group in the inner main belt. Its age has been estimated by several researchers to be less then 300 My, so it is a relatively young cluster. Yarko-YORP Monte Carlo methods to study the chronology of the Erigone family confirm results obtained by other groups. The Erigone family, however, is also characterized by its interaction with the $z_2$ secular resonance. While less than 15% of its members are currently in librating states of this resonance, the number of objects, members of the dynamical group, in resonant states is high enough to allow to use the study of dynamics inside the $z_2$ resonance to set constraints on the family age. Like the ${\nu }_6$ and $z_1$ secular resonances, the $z_2$ resonance is characterized by one stable equilibrium point at $\sigma =180^{\circ }$ in the $z_2$ resonance plane $(\sigma ,\frac{d\sigma }{dt})$, where $\sigma$ is the resonant angle of the $z_2$ resonance. Diffusion in this plane occurs on timescales of $\simeq 12$ My, which sets a lower limit on the Erigone family age. Finally, the minimum time needed to reach a steady-state population of $z_2$ librators is about 90 My, which allows to impose another, independent constraint on the group age.

This paper has 11 pages, 12 figures, and 1 table. Accepted for publication in MNRAS

References in corpus (2)

• Asteroid family ages
• Constraining the cometary flux through the asteroid belt during the late heavy bombardment

Cited by in corpus (7)

• Yarkovsky V-shape identification of asteroid families
• Asteroid families interacting with secular resonances
• Hierarchical Clustering in Astronomy
• Size-dependent modification of asteroid family Yarkovsky V-shapes
• Asteroid cratering families: recognition and collisional interpretation
• On the Astrid asteroid family
• A pre-flyby view on the origin of asteroid Donaldjohanson, a target of the NASA Lucy mission