TY - JOUR
T1 - Hektor - an exceptional D-type family among Jovian Trojans
AU - Rozehnal, J.
AU - Brož, M.
AU - Nesvorný, D.
AU - Durda, D. D.
AU - Walsh, K.
AU - Richardson, D. C.
AU - Asphaug, E.
N1 - Publisher Copyright:
© 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2016/11/1
Y1 - 2016/11/1
N2 - In this work, we analyse Jovian Trojans in the space of suitable resonant elements and we identify clusters of possible collisional origin by two independent methods: the hierarchical clustering and a so-called randombox. Compared to our previous work, we study a twice larger sample. Apart from Eurybates, Ennomos and 1996 RJ families, we have found three more clusters - namely families around asteroids (20961) Arkesilaos, (624) Hektor in the L4 libration zone and (247341) 2001UV209 in L5. The families fulfill our stringent criteria, i.e. a high statistical significance, an albedo homogeneity and a steeper size-frequency distribution than that of background. In order to understand their nature, we simulate their long term collisional evolution with the Boulder code and dynamical evolution using a modified SWIFT integrator. Within the framework of our evolutionary model, we were able to constrain the age of the Hektor family to be either 1-4 Gyr or, less likely, 0.1-2.5 Gyr, depending on initial impact geometry. Since (624) Hektor itself seems to be a bilobed-shape body with a satellite, i.e. an exceptional object, we address its association with the D-type family and we demonstrate that the moon and family could be created during a single impact event. We simulated the cratering event using a smoothed particle hydrodynamics. This is also the first case of a family associated with a D-type parent body.
AB - In this work, we analyse Jovian Trojans in the space of suitable resonant elements and we identify clusters of possible collisional origin by two independent methods: the hierarchical clustering and a so-called randombox. Compared to our previous work, we study a twice larger sample. Apart from Eurybates, Ennomos and 1996 RJ families, we have found three more clusters - namely families around asteroids (20961) Arkesilaos, (624) Hektor in the L4 libration zone and (247341) 2001UV209 in L5. The families fulfill our stringent criteria, i.e. a high statistical significance, an albedo homogeneity and a steeper size-frequency distribution than that of background. In order to understand their nature, we simulate their long term collisional evolution with the Boulder code and dynamical evolution using a modified SWIFT integrator. Within the framework of our evolutionary model, we were able to constrain the age of the Hektor family to be either 1-4 Gyr or, less likely, 0.1-2.5 Gyr, depending on initial impact geometry. Since (624) Hektor itself seems to be a bilobed-shape body with a satellite, i.e. an exceptional object, we address its association with the D-type family and we demonstrate that the moon and family could be created during a single impact event. We simulated the cratering event using a smoothed particle hydrodynamics. This is also the first case of a family associated with a D-type parent body.
KW - Celestial mechanics
UR - http://www.scopus.com/inward/record.url?scp=84989181004&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84989181004&partnerID=8YFLogxK
U2 - 10.1093/mnras/stw1719
DO - 10.1093/mnras/stw1719
M3 - Article
AN - SCOPUS:84989181004
SN - 0035-8711
VL - 462
SP - 2319
EP - 2332
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -