ARGO-YBJ is a full coverage air shower detector currently under construction
at the Yangbajing Laboratory (4300 m a.s.l., Tibet, China). First data obtained
with a subset of the apparatus will be available in summer 2003 while the full
detector operation is expected in 2005. One of the main aims of ARGO-YBJ is the
observation of gamma-ray sources, at an energy threshold of a few hundreds GeV.
In this paper we present the expected sensitivity to detect point gamma ray
sources, with particular attention to the Crab Nebula. According to our
simulations a Crab-like signal could be detected in one year of operation with
a statistical significance of 10 standard deviations, without any gamma/hadron
discrimination.Comment: 4 pages, 2 Postscript figure
