Medium-resolution Isaac Newton Telescope library of empirical spectra

This article has been accepted for publication in Monthly notices of the Royal Astronomical Society. © 2006 The Authors. Journal compilation © 2006 RAS. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. We are indebted to the referee, Guy Worthey, for noting the presence of scattered light in the first version of the library. We would also like to thank Scott C. Trager for the careful reading of this manuscript and for his very useful comments and to Ricardo Schiavon for helping us find references to correct the spectra for atmospheric extinction. This paper is based on observations obtained at the Isaac Newton Telescope, operated by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. This work was supported by the Spanish research project AYA2003-01840. This work has made extensive use of the SIMBAD data base. We are grateful to the ASTRON-PC and CAT for generous allocation of telescope time. AV is a Ramón y Cajal Fellow of the Spanish Ministry of Education and Science. This work has been supported by the Spanish Ministry of Education and Science (grant AYA2004-03059).