Consistency of Pantheon plus supernovae with a large-scale isotropic universe

We investigate the possible anisotropy of the universe using the most up-to-date type Ia supernovae, i.e. the Pantheon+ compilation. We fit the full Pantheon+ data with the dipole-modulated Lambda CDM model, and find that it is well consistent with a null dipole. We further divide the full sample into several subsamples with different high-redshift cutoff z(c). It is shown that the dipole appears at 2 sigma confidence level only if z(c)<= 0.1, and in this redshift region the dipole is very stable, almost independent of the specific value of zc. For z(c)=0.1, the dipole amplitude is D=1.0(-0.4)(+0.4)x10(-3), pointing towards (l,b)=(334.5 degrees(+25.7 degrees) (-21.6 degrees),16.0 degrees(+27.1 degrees) (-16.8 degrees)), which is about 65 degrees away from the CMB dipole. This implies that the full Pantheon+ is consistent with a large-scale isotropic universe, but the low-redshift anisotropy couldn't be purely explained by the peculiar motion of the local universe.