  An escape-suppressed, composite high-purity germanium detector of the Clover
type has been installed at the Laboratory for Underground Nuclear Astrophysics
(LUNA) facility, deep underground in the Gran Sasso Laboratory, Italy. The
laboratory gamma-ray background of the Clover detector has been studied
underground at LUNA and, for comparison, also in an overground laboratory.
Spectra have been recorded both for the single segments and for the virtual
detector formed by online addition of all four segments. The effect of the
escape-suppression shield has been studied as well. Despite their generally
higher intrinsic background, escape-suppressed detectors are found to be well
suited for underground nuclear astrophysics studies. As an example for the
advantage of using a composite detector deep underground, the weak ground state
branching of the Ep = 223 keV resonance in the 24Mg(p,gamma)25Al reaction is
determined with improved precision.
