Hostname: page-component-848d4c4894-nr4z6 Total loading time: 0 Render date: 2024-06-03T06:44:46.071Z Has data issue: false hasContentIssue false

Minor mergers and their impact on the kinematics of galaxy discs

Published online by Cambridge University Press:  15 February 2011

P. Di Matteo
Affiliation:
GÉPI, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France
Y. Qu
Affiliation:
GÉPI, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France
M.D. Lehnert
Affiliation:
GÉPI, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France
W. van Driel
Affiliation:
GÉPI, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France
C.J. Jog
Affiliation:
Department of Physics, Indian Institute of Science, Bangalore 560012, India
Get access

Abstract

By means of N-body simulations, we have investigated the impact of minor mergers on the angular momentum content and kinematical properties of a disc galaxy. Our simulations cover a range of initial orbital characteristics and the system consists of a massive galaxy with a bulge and a stellar disc merging with a much less massive gasless companion. Our results show that: (1) during the process of merging, the disc of the primary galaxy becomes kinematically hotter and thicker; (2) its specific angular momentum always decreases, independent of the orbit or morphology of the satellite galaxy; (3) the decrease in the rotation velocity of the primary galaxy is accompanied by a change in the anisotropy of the stellar orbits, which becomes increasingly radially dominated as the merger advances; (4) the radial velocity dispersion increases at all radii, but in particular in the outermost regions; (5) at the same time, the transverse velocity decreases throughout the whole disc, except in the inner region, where the constribution of bulge stars leads to an increase of σt.

Type
Research Article
Copyright
© EAS, EDP Sciences 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Références

Aguirre, P., Uson, J.M., & Matthews, L.D., 2009, RMxAC, 35, 201
Balcells, M., van Gorkom, J.H., Sancisi, R., & del Burgo, C., 2001, AJ, 122, 1758 CrossRef
Barnes, J.E., 1992, ApJ, 393, 484 CrossRef
Barnes, J.E., & Hernquist, L., 1996, ApJ, 471, 115 CrossRef
Di Matteo, P., Jog, C.J., Lehnert, M.D., et al., 2009, A&A, 501, L9
Gilmore, G., Wyse, R.F.G., & Norris, J.E., 2002, ApJ, 574, L39 CrossRef
Helmi, A., 2008, A&ARv, 15, 145
Jesseit, R., Cappellari, M., Naab, T., et al., 2009, MNRAS, 397, 1202 CrossRef
Kenney, J.D.P., Tal, T., Crowl, H.H., et al., 2008, ApJ, 687, L69 CrossRef
Kreckel, K., Platen, E., Aragón-Calvo, M.A., et al., 2010, ApJ, in press [astro-ph/1008.4616]
McMillan, P.J., Athanassoula, E., & Dehnen, W., 2007, MNRAS, 376, 1261 CrossRef
Qu, Y., Di Matteo, P., Lehnert, M.D., van Driel, W., & Jog, C., 2010, A&A, 515, 11
Serra, P., Trager, S.C., van der Hulst, J.M., et al., 2006, A&A, 453, 493
Sikkema, G., Carter, D., Peletier, R.F., et al., 2007, A&A, 467, 1011
Vollmer, B., Braine, J., Combes, F., & Sofue, Y., 2005, A&A, 441, 473
Yoachim, P., & Dalcanton, J., 2008, ApJ, 682, 1004CrossRef