Merged catalogue of reflection nebulae Several catalogues of reflection nebulae are merged to create a uniformcatalogue of 913 objects. It contains revised coordinates,cross-identifications of nebulae and stars, as well as identificationswith IRAS point sources.The catalogue is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (22.214.171.124) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/399/141
Gas and dust in the Ophiuchus region The interstellar gas and dust in the Ophiuchus molecular cloud regionare studied through H I, CO, and IRAS observations. The generally goodglobal correlation of H I with the infrared intensity and dust opticaldepth breaks down on the smaller scales that can be distinguished inthis nearby region. The presence of an intense ultraviolet field andshocks caused by the early-type stars can account for this difference.Integrated emission from the CO molecule correlates with the dustoptical depth. This correlation is used to derive the conversion factorbetween W(CO) and the atomic hydrogen column density. The region closeto the early-type stars in Upper Scorpius shows a considerable amount ofinfrared emission, but negligible CO emission.