Quadruple-peaked spectral line profiles as a tool to constrain gravitational potential of shell galaxies

0387366 - ASÚ 2013 RIV FR eng J - Journal Article
Ebrová, Ivana - Jílková, L. - Jungwiert, Bruno - Křížek, Miroslav - Bílek, M. - Bartošková, Kateřina - Skalická, T. - Stoklasová, Ivana
Quadruple-peaked spectral line profiles as a tool to constrain gravitational potential of shell galaxies.
Astronomy & Astrophysics. Roč. 545, September (2012), A33/1-A33/15. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR GD205/08/H005; GA MŠMT(CZ) LC06014
Institutional support: RVO:67985815
Keywords : galaxies * kinematics and dynamics * numerical methods
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Impact factor: 5.084, year: 2012

The resulting line-of-sight velocity distributions are more complex than previously predicted due to nonzero phase velocity of the shells. In principle, each of the Merrifield & Kuijken (1998) peaks splits into two, giving a quadruple-peaked line profile, which allows more precise determination of the potential of the host galaxy and contains additional information. We find simple analytical expressions that connect the positions of the four peaks of the line profile and the mass distribution of the galaxy, namely, the circular velocity at the given shell radius and the propagation velocity of the shell. The analytical expressions were applied to a test-particle simulation of a radial minor merger, and the potential of the simulated host galaxy was successfully recovered. Shell kinematics can thus become an independent tool to determine the content and distribution of the dark matter in shell galaxies up to similar to 100 kpc from the center of the host galaxy.
Permanent Link: http://hdl.handle.net/11104/0217835