A class of matrix models which arises as partition function in U(N)
Chern-Simons matter theories on three sphere is investigated. Employing the
standard technique of the 1/N expansion we solve the system beyond the planar
limit. In particular we study a case where the matrix model potential has 1/N
correction and give a general solution thereof up to the order of 1/N^2. We
confirm that the general solution correctly reproduces the past exact result of
the free energy up to the order in the case of pure Chern-Simons theory. We
also apply to the matrix model of N=2 Chern-Simons theory with arbitrary
numbers of fundamental chiral multiplets and anti-fundamental ones, which does
not admit the Fermi gas analysis in general.Comment: 1+29 pages, 2 figures, v2: some improvements, figures added, v3:
genus half loop equation solved, calculation for confirmation of the
solution, further discussion, improvements, references added, v4: minor
improvements, a new example, a reference added, published versio
