IAU Symposium Abstract S186-063P

**
ELLIPTICALS FORMATION: WHAT MODE HAS A HIGHEST INCREMENT ?
**

S.N.NURITDINOV
Tashkent State University, Tashkent, Uzbekistan, CIS < nurit@astro.gov.uz >

Our theoretical study of the stability problem of the non-
linear non-equilibrium self-gravitating models shows that the
physical result are essentially differing from the instability
of corresponding equilibrium models. For example, in paper [1,2]
we indicated the instability increments of the "egg-shaped"
perturbations mode more than the increments of the elliptic mode.
To study of the elliptic mode evolution on background of
the [3] non-equilibrium collapsing model, at first, we constructed
the series of analitical models of pulsating with arbitrary
amplitude ( equal to 1-(2T/U)_{o}, where (2T/U)_{o} - the virial
parameter for moment at t=0) of the collapsing rotating galaxies.
(These models are the generalizations of Camm, Einstein and
Freeman). Then we analyse a stability problem of the non-linear
non-equilibrium models. The dependences of the instability
increments on (2T/U)_{o} for different values of the rotation
parameter are found. They will be presented in the report.
Besides, it will also be discussed the physical sence of this
phenomenon.

REFERENCES
1. Nuritdinov S.N. 1991. Astron.Zh.Sov.V.68.N 4,763

2. Nuritdinov S.N. 1985. Astron.Zh.Sov.V.62.N 3,506

3. Nuritdinov S.N. 1992. Astron.Tsirk.Acad.Scin.of Russ. N 1553,9