Bibcode
DOI
Borne, Kirk D.; Balcells, Marc; Hoessel, John G.
Referencia bibliográfica
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 333, Oct. 15, 1988, p. 567-585. Research supported by the Space Telescope Science Institute.
Fecha de publicación:
10
1988
Revista
Número de citas
43
Número de citas referidas
39
Descripción
The authors have determined the masses and orbital parameters for the
galaxies in the strongly interacting binary NGC 4782/4783 by finding a
numerical simulation of the collision that accurately represents all of
the observed properties of the system. With this simulation, the authors
have completely determined the three-dimensional orientation and the
dynamical state of the binary. The large relative velocity observed for
the pair is the consequence of a high-speed encounter and is not an
indicator of large galaxian masses. Large stellar velocity dispersions
provide evidence for a tidal shock and are likewise not indicative of a
large amount of mass. Some of the physical parameters that define the
solution for the pair are (for H0 = 60 km
s-1Mpc-1): log Mtot/M_sun; = 12.14,
true relative velocity in plane of orbit 690 km s-1, true
separation in plane of orbit 20.0 kpc, time since pericenter passage
≈25 million years, and time until merger (i.e., pair coalescence)
≈800 million years. Large velocity dispersions (from the shock) and
strong distortions in the luminous matter distribution provide evidence
for tidal stripping and tidal transfer of orbital energy and angular
momentum into individual stars.