Address:
A. Al-Omari, Al al-Bayt University, Faculty of Sciences, Department of Mathematics, P.O. Box 130095, Mafraq 25113, Jordan
T. Noiri, 2949-1 Shiokita-cho, Hinagu, Yatsushiro-shi, Kumamoto-ken, 869-5142 Japan
E-mail:
omarimutah1@yahoo.com
t.noiri@nifty.com
Abstract: A topological space $(X, \tau )$ is said to be $z$-Lindelöf [1] if every cover of $X$ by cozero sets of $(X,\tau )$ admits a countable subcover. In this paper, we obtain new characterizations and preservation theorems of $z$-Lindelöf spaces.
AMSclassification: primary 54C05; secondary 54C08, 54C10.
Keywords: cozero set, \omega -open set, Lindelöf, z-Lindelöf.
DOI: 10.5817/AM2017-2-93