Essential Norm of Extended Cesàro Operators between Bloch-type Spaces

摘要

The Bloch-type space Bω consists of all functions f ∈ H(B) for which||f||Bω=sup/z∈Bω(z)|▽f(z)|< ∞.Let T be the extended Ces`aro operator with holomorphic symbol . The essential norm of T as an operator from Bω to Bμ is denoted by ||T||e,B ω→Bμ . The purpose of this paper is to prove that, for ω, μ normal and ∈H(B)||T||e,B ω→Bμ■ lim sup|z|→1 μ(z)|■ (z)|∫ |z| 0 dt ω(t) .