The ground-based data are stored in a single FITS image per file. The data are organized to have all images for a given week stored in one directory. For example, the data taken during week 47 of 1992 (from 15-Nov-92 through 21-Nov-92 inclusive) would be in the directory /yd0/gbo92_47a at the ISAS system.
The Yohkoh file naming convention for ground-based data is similar to that used for Yohkoh data. There is a three letter prefix followed by the normal file ID portion (YYMMDD.HHMM) (see the Reference Guide section defining the Yohkoh FileIDs). The first letter of the three letter prefix is always `g' to signify ground-based data. The second letter is the institute where the data was taken. The letters assigned to the institutes are:
B = Big Bear C = Boulder Colorado G = Goddard Space Flight Center H = Holloman J = CRL/Hiraiso K = Kitt Peak L = Learmonth, Australia N = NAOJ, Nobeyama, Norikura P = Palehua (SOON) R = Ramey (SOON) S = San Vito (SOON)
The last letter is the type of data that is in the file. The letters assigned to the types of images are:
C = Large Scale H-Alpha G = Green Line Image (5303 A) H = H-alpha I = HeI 10830 A K = Calcium M = Magnetogram P = Polarized Radio (17 GHz) (R-L) R = Red Line Image (6374 A) S = Spectrohelioscope T = Total Intensity Radio (17 GHz) (R+L) W = white light X = X-ray Y = Yellow Line Image (5694 A)
A sample name is /yd0/gbo93_01a/gkm930101.1657 for the ISAS system. NOTE: The GBO files online could be compressed so that there is a ``.Z'' at the end of the file name. The reading routine RFITS2 (and YODAT) will handle these compressed files automatically.