EDP Sciences
Free access
Volume 402, Number 2, May I 2003
Page(s) 531 - 539
Section Stellar clusters and associations
DOI http://dx.doi.org/10.1051/0004-6361:20030280

A&A 402, 531-539 (2003)
DOI: 10.1051/0004-6361:20030280

Projected properties of a family of triaxial mass models: High-order residuals

D. K. Chakraborty and M. Das

School of Studies in Physics, Pt. Ravishankar Shukla University, Raipur 492 010, India
(Received 27 May 2002 / Accepted 18 February 2003 )

A family of triaxial mass models is described, for which the projected surface density can be calculated analytically, and can show ellipticity variations, isophote twists and high-order residuals. These can be compared with observations. These models are flattened versions of the $\gamma$-model with density $\rho(r) \ \propto \ r^{-\gamma}(b_{0}+r)^{\gamma-4}$ and the modified Hubble model with density profile $\rho(r) \ \propto \ (b_{0}^{2}+r^{2})^{-3/2}$, and are constructed by addition of five spherical harmonic terms to the spherical models. The potential of the models can be expressed in a simple form.

Key words: galaxies: photometry -- galaxies: structure

Offprint request: D. K. Chakraborty, ircrsu@sancharnet.in

© ESO 2003