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Zusammenfassung:
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The main goal of this dissertation is improvement of an approach for identi-
cation of the members of asteroid families, based on the hierarchical clustering
method. An additional step is introduced in order to reduce a so-called chaining
e ect. The introduced algorithm consists of four main steps. In the rst step, the
hierarchical clustering method is applied to the initial catalogue of proper elements
in order to obtain a preliminary list of family members. In the second step, using
available physical properties, and based upon the de ned criteria, the interlopers are
identi ed. In the third step, objects identi ed as interlopers in the second step, are
excluded from the initial catalogue of proper orbital elements, producing a modi ed
catalogue. Finally, in the fourth step, the HCM analysis is performed again, but this
time using the modi ed catalogue of proper elements. It is shown that in this way
a number of potential interlopers among family members is signi cantly reduced.
Moreover, an on-line based portal (Asteroids Families Portal; AFP) to apply this
procedure is developed, and is freely available to all interested researchers.
The second goal of the dissertation is to determine the limitations of the backward
integration method, used for estimation of ages of young asteroid families. This
aim is achieved through numerical simulations of the evolution of a ctitious family.
By determining instants of secular angles
i $ clustering, a linear relationship is
found between the depth of a clustering and the age of a family. According to the
obtained results, the backward integration method could be successfully applied to
families not older than 18 Myrs. |