Analyses of type ia supernova data in cosmological models with a local void

The data for type la supernovae obtained by the High-z SN Search Team and Supernova Cosmology Project are analyzed using inhomogeneous cosmological models with a local Void on scales of about 200 Mpc, to derive the best-fit values of model parameters and the confidence contours. The chi (2) fitting is found to be slightly better than that in homogeneous models. It is shown that (1) the best-fit values are most sensitive to the ratio R of the outer Hubble constant, H-0(II), to the inner Hubble constant, H-0(I), (2) the best-fit outer density parameter, Omega (II)(0) and cosmological constant parameter, lambda (II)(0), are, respectively, increasing and decreasing functions of R, and (3) (Omega (II)(0), lambda (II)(0)) can be (1, 0) for R approximate to 0.8. Moreover, it is shown that these models are naturally consistent with the new supernova data (SN1997ff) with z = 1.7.