Generalized Hilbert Operators on Bergman and Dirichlet Spaces of Analytic Functions
Tom 63 / 2015
Streszczenie
Let be an analytic function on the unit disk \mathbb {D}. We define a generalized Hilbert-type operator \mathcal {H}_{a,b} by \mathcal {H}_{a,b}(f)(z)=\frac {\varGamma (a+1)}{\varGamma (b+1)}\int _{0}^{1}\frac {f(t)(1-t)^{b}}{(1-tz)^{a+1}} \,dt, where a and b are non-negative real numbers. In particular, for a=b=\beta ,\nobreakspace {}\mathcal {H}_{a,b} becomes the generalized Hilbert operator \mathcal {H}_\beta , and \beta =0 gives the classical Hilbert operator \mathcal {H}. In this article, we find conditions on a and b such that \mathcal {H}_{a,b} is bounded on Dirichlet-type spaces S^{p}, 0 \lt p \lt 2, and on Bergman spaces A^{p}, 2 \lt p \lt \infty . Also we find an upper bound for the norm of the operator \mathcal {H}_{a,b}. These generalize some results of E. Diamantopolous (2004) and S. Li (2009).