Dynamical analyses on the transitivity from JFC and Centaur regions to NEAs with Tisserand parameters from 2 to 3

We study the contribution of JFC (Jupiter family comet) and Centaur regions to the NEA (near Earth asteroid) population having Tisserand parameters for Jupiter between 2 and 3. We define a region for JFCs (aphelion distance (Q) > 4.61 au, perihelion distance (q) < 4.95 au, > 1.3 au) and we check the contributions of selected bodies (JFCs, Centaurs, Halley-type comets (HTCs), some elliptic comets, and some outer main belt asteroids) from various regions to the NEA region. Additionally, we integrated NEAs with Tisserand parameters for Jupiter (T-J) between 2 and 3 and their clones backward in time to see whether there was a strong dynamical path between those NEAs and the defined JFC region. As a result, 35.1% of the orbits from the defined JFC region turned out to be Earth-crossing orbits for forward integrations, while 66.7% of NEAs (2 < T-J < 3) reached the JFC region for backward integrations. Considering these probabilities, 304 orbits of today's JFC regional bodies can contribute the Earth-crossing asteroids in 0.55 Myr. Almost 254 NEA regional bodies look like they came from the defined region in a comparable time interval (0.80 Myr). (C) 2016 COSPAR. Published by Elsevier Ltd. All rights reserved.