The BaSeL Libraries ------------------- Format of the BaSeL 2.2 (Lejeune, Cuisiner, and Buser, 1998 A&AS, 130, 65) and BaSeL 3.1 (Westera, Lejeune, Buser, Cuisinier, and Bruzual A., 2002 A&A, 381, 524) libraries. The files are in the Kurucz format, which is as follows: The (ascii) files are subdivided in blocks: The first block (lines 1-153) contains the 1221 wavelengths of the spectra in nm (in the FORTRAN format 8f10.1). Since for each file, all spectra are on the same wavelength grid, they appear only once, at the beginning of the file.: 9.1 9.4 9.6 9.8 10.0 10.2 10.4 10.6 10.8 11.0 11.4 11.8 12.1 12.5 12.7 12.8 . . . . 9860.0 9900.0 9940.0 9980.0 10020.0 20000.0 40000.0 60000.0 80000.0 100000.0 120000.0 140000.0 160000.0 The other blocks (176 lines each) contain the individual spectra. The first line of each such block contains the parameters of the spectrum given in that block: the spectrum number, the effective temperature T_eff, the surface gravity log(g), the metallicity [Fe/H], the turbulent velocity (which is not used, so it is always zero), and the number fraction of hydrogen (also not used) in the FORTRAN format (2i6,4f6.2): 1 2000 3.50 -0.50 0.00 0.00 The other 175 lines of each block contain the (1221) flux values at the wavelengths of the grid in erg/s/cm/cm/Hz (FORTRAN format 7e11.4). 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 . . . . 0.5088E-07 0.5056E-07 0.1542E-07 0.4235E-08 0.1942E-08 0.1109E-08 0.7161E-09 0.5003E-09 0.3692E-09 0.2836E-09 There is some confusion about the flux unit, though. In the paper, where the format is defined, the text suggests there's an additional 1/steradian (making it erg/s/cm^2/Hz/steradian), so depending on your application you might have to multiply or divide by 4pi. If you have any doubts or suggestions, please don't hesitate to contact me. Pieter Westera