@Article{ ChFaMePa5, author = { Chill, Ralph and Fasangova, Eva and Metafune, Giorgio and Pallara, Diego }, title = { The sector of analyticity of the Ornstein-Uhlenbeck semigroup on $L^p$ spaces with respect to invariant measure }, journal = { The Journal of the London Mathematical Society }, year = { 2005 }, volume = { 71 }, pages = { 703-722 }, URL = { http://cvgmt.sns.it/paper/2552/ }, note = { cvgmt preprint} }