Press-Schechter, thermodynamics and gravitational clustering

Details Press-Schechter, thermodynamics and gravitational clustering Press-Schechter, thermodynamics and gravitational clustering

May 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995mnras.274..213s&link_type=abstract

Monthly Notices of the Royal Astronomical Society, Volume 274, Issue 1, pp. 213-220.

Astronomy and Astrophysics

Astronomy

13

Galaxies: Clusters: General, Galaxies: Evolution, Galaxies: Formation, Cosmology: Theory, Dark Matter

Scientific paper

For the special case of non-linear gravitational clustering from an initially Poissonian distribution, the counts-in-cells distribution function is obtained from the excursion set, Press-Schechter multiplicity function. This Poisson Press-Schechter distribution function has the same form as the gravitational quasi-equilibrium counts-in-cells distribution function, predicted by the Saslaw-Hamilton thermodynamic model of non-linear gravitational clustering, which fits the observed galaxy distribution well. By changing an ad hoc guess in the Saslaw-Hamilton thermodynamic model, the negative binomial distribution (which also fits relevant observations well) is derived from the thermodynamic approach. At present, analytic simplicity is the primary reason for preferring one guess over another, so the thermodynamic approach does not, at present, yield a unique prediction for the gravitational counts-in-cells distribution function. Two ways to constrain the parameter space of possible guesses are described; one of these suggests that the negative binomial is not a physically reasonable model. One possible relation between the original Saslaw-Hamilton thermodynamic model and the Poisson Press-Schechter approach is obtained. A system of non-interacting, virialized clusters having a range of masses, the distribution of masses being given by the Poisson Press-Schechter multiplicity function, is shown to be consistent with the original Saslaw-Hamilton thermodynamic model. For this model to work, the virialized clusters must be in thermal equilibrium with each other, so that all clusters have the same temperature, independent of their masses. This last requirement and the idealization that the clusters do not interact gravitationally with each other are in contradiction with observations.

Affiliated with

Also associated with

No associations

Rating

Press-Schechter, thermodynamics and gravitational clustering does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Press-Schechter, thermodynamics and gravitational clustering, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Press-Schechter, thermodynamics and gravitational clustering will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1061675