Initial velocity V-shapes of young asteroid families

Abstract

Ejection velocity fields of asteroid families are largely unconstrained due to the fact that members disperse relatively quickly on Myr time-scales by secular resonances and the Yarkovsky effect. The spreading of fragments in $a$ by the Yarkovsky effect is indistinguishable from the spreading caused by the initial ejection of fragments. By examining families $<$20 Myrs-old, we can use the V-shape identification technique to separate family shapes that are due to the initial ejection velocity field and those that are due to the Yarkovsky effect. $<$20 Myr-old asteroid families provide an opportunity to study the velocity field of family fragments before they become too dispersed. Only the Karin family's initial velocity field has been determined and scales inversely with diameter, $D^{-1}$. We have applied the V-shape identification technique to constrain young families' initial ejection velocity fields by measuring the curvature of their fragments' V-shape correlation in semi-major axis, $a$, vs. $D^{-1}$ space. Curvature from a straight line implies a deviation from a scaling of $D^{-1}$. We measure the V-shape curvature of 11 young asteroid families including the \FYnospace, Aeolia, Brangane, Brasilia, Clarissa, Iannini, Karin, Konig, Koronis(2), Theobalda and Veritas asteroid families. We find that the majority of asteroid families have initial ejection velocity fields consistent with $\sim D^{-1}$ supporting laboratory impact experiments and computer simulations of disrupting asteroid parent bodies.

arXiv comment68 Pages, 25 Figures, 2 Tables, accepted for publication in MNRAS

References in corpus (22)

• Density of asteroids
• Thermal inertia of near-Earth asteroids and implications for the magnitude of the Yarkovsky effect
• Asteroid families classification: exploiting very large data sets
• The Yarkovsky and YORP Effects
• Identification and Dynamical Properties of Asteroid Families
• Asteroid family ages
• Introducing the Eulalia and new Polana asteroid families: re-assessing primitive asteroid families in the inner Main Belt
• Asteroid thermophysical modeling
• Asteroid family identification using the Hierarchical Clustering Method and WISE/NEOWISE physical properties
• Constraining the cometary flux through the asteroid belt during the late heavy bombardment
• Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - preliminary results
• Revising the age for the Baptistina asteroid family using WISE/NEOWISE data
• Yarkovsky V-shape identification of asteroid families
• Constraints on the original ejection velocity fields of asteroid families
• Redetermination of the space weathering rate using spectra of Iannini asteroid family members
• Collisional Formation and Modeling of Asteroid Families
• An automatic approach to exclude interlopers from asteroid families
• Chaotic Transport and Chronology of Complex Asteroid Families
• Detection of the YORP Effect for Small Asteroids in the Karin Cluster
• SPH/N-body simulations of small (D = 10 km) asteroidal breakups and improved parametric relations for Monte-Carlo collisional models
• Detection of the Yarkovsky effect for C-type asteroids in the Veritas family
• Characterizing the original ejection velocity field of the Koronis family

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