Singular isothermal sphere profile

The singular isothermal sphere (SIS) profile is the simplest parameterizationdn of the spatial distribution of matter in an astronomical system (e.g. galaxies, clusters of galaxies, etc.) [cite journal| first = C. | last = Keeton | year = 2002 | month = June | title = A Catalog of Mass Models for Gravitational Lensing| journal = eprint arXiv:astro-ph/0102341| bibcode=2001astro.ph..2341K|accessdate = 2008-06-01] .

Density distribution

$ho(r)\; =\; frac\{sigma\_\{V\}^\{2\{2pi\; G\; r^\{2$

where σ_V² is the velocity dispersion and G is the gravitational constant. The SIS profile is unphysical because of the singularity at zero radius and the fact that the corresponding SIS mass is infinite. However, it is commonly utilized in the literature due to the simplicity of its form.

References

ee also

*Navarro-Frenk-White profile