A&A Supplement series, Vol. 123, May II 1997, 93-101
Received June 14; accepted September 10, 1996
Bootis stars
E. Paunzen 
, W.W. Weiss 
, U. Heiter 
, and P. North 
Send offprint request: E. Paunzen
Institut für Astronomie, Türkenschanzstr. 17, A-1180 Wien,
Austria
e-mail: last_name@astro.ast.univie.ac.at
Institut d'Astronomie de l'Université de Lausanne, CH-1290
Chavannes-des-Bois, Switzerland
e-mail: Pierre.North@obs.unige.ch
Bootis stars challenge our understanding of diffusion and accretion processes
related
to stars and their circumstellar environment, and they are interesting
components
of the classical instability strip.
Attempts to derive group
properties with statistical methods are severely limited by the small
number of unambiguously
identified 
Bootis stars. In general, the subject appears to be obscured by
incorrect memberships and it is therefore essential to provide
a sufficiently large catalogue of definitive group members before modeling
the 
Bootis phenomenon.
This paper describes the
first steps towards this goal, based on our current knowledge
of well investigated
members, leading to
a concise definition of 
Bootis stars:
PopI hydrogen burning metal poor (except of C,N,O and S) A-type stars.
The definition does not depend on phenomenological features, like
flux depressions, colour
excesses, 
values, etc.
Based on a new homogeneous catalogue with 45 
Bootis stars, we discuss
classification criteria which can be used for a spectroscopic and
photometric all-sky
survey for 
Bootis stars in the field and in clusters of different ages.
keywords: astronomical data bases -- catalogues; stars -- 
Bootis\; stars --
chemically peculiar;
stars -- early type
Bootis stars