The Einstein On-line Service (EOLS, or EINLINE) at the Harvard-Smithsonian Center for Astrophysics (CfA) provides access to over 100 data sets (catalogs and mission logs). Many are related to the Einstein X-ray satellite archive, but catalogs of stars, quasars, radio sources (see below), supernova remnants, as well as ROSAT observations can be found. Documentation and ASCII files generated by user queries can be automatically e-mailed to users, and binary data files (such as FITS images from the Einstein CD-ROM collection) can be retrieved using anonymous FTP. There are 31 CD-ROMs available for downloading images and/or photon (list) arrays. EINLINE allows positional searches through groups of similar data sets (all X-ray, all radio, or even ALL catalogs) in one run. This is the MQQ (multiple quick query) option. As a rule, EOLS catalogs are also available through NASA's Astrophysics Data System (ADS, see §3.4.1.).
A special feature of EOLS is the large number of searchable radio-source catalogs collected and provided by the first of the present authors in the course of his activities for the IAU Working Group on Radioastronomical Databases (Comm. 40). As of June 1994, some 55 source catalogs with about 510,000 entries are searchable, either individually or in affinity groups. This exceeds by several times the amount of radio-source data available from any other on-line service, and most of the tables are not (yet) archived at the established data centers. Some 10,000 lines of documentation have been prepared by the EOLS team, but further submissions of data must be accompanied by appropriate documentation provided by the authors to guarantee their incorporation into EOLS.
Log on to EOLS via telnet to einline.harvard.edu (128.103.40.204), via SET HOST EINLINE (6714) or else via the WWW under URL http://hea-www.harvard.edu/einline/einline.html. Login as user einline; no password is required. Documentation for the catalogs can be e-mailed directly from within the EOLS or downloaded with FTP from the directories einline.harvard.edu:Doc/.... Documents for any of the catalogs can serve as templates for new contributions. For questions, contact Dan Harris (harris@cfa.harvard.edu) or Carolyn Stern Grant (stern@cfa.harvard.edu). [References: HEAO Newsletters (subscribe to edpo@head-cfa.harvard.edu), Andernach (1992), Harris et al. (1992), Andernach (1994), Andernach et al. 1994.]