The ROSAT Data Archive lies in the subdirectory `data' of directory `archive'. The data are stored in compressed form (using the public domain utility gzip) and therefore, after network transfer, have to be decompressed at the users site (subdirectory archive/tools contains help info and gzip code for UNIX and VMS systems).
Data from a specific observation, identified by its sequence number (6 digits) and an additional identifier (`p' for PSPC, `f' for PSPC with filter and `h' for HRI data), are stored in a subdirectory of directory `archive/data'. PSPC data with sequence number 123456, for example, are stored in directory `archive/data/123456p'. Follow up observation(s) have a postfix of `-1', `-2', ... E.g., the data of the first follow up observation of the above example are in archive/data/123456p-1.
Example session (copy data of PSPC observation 200014p):
% ftp rosat_svc.mpe-garching.mpg.de connect to the Service Area
user: anonymous; password: e-mail address
ftp> cd archive/data go to RDA main directory
ftp> cd 200014p proceed to proper observation directory
ftp> bin set binary mode transfer
ftp> prompt avoid prompting using mget
ftp> mget * copy all files from the directory
ftp> bye leave ftp
% gzip -d *-gz decompress files
Now the data (in FITS format) are ready for input to one of the interactive analysis systems (EXSAS, PROS).
To receive data on tape (cassette), archive requests may also be sent via mail or e-mail to the RSDC. The proper request form is available in directory `archive'.