There is no continuum (SUBCONT=F) and the spectrum is linear in wavelength (DC-FLAG=0). Both it and an object spectrum to be correlated against it need to be low-pass filtered; high-pass filtering removes emission line information (FI-FILT=3). The EMLINEn parameters give the name, rest and file center wavelenghts, height, width, two zeroes, area, and weight for each emission line in the spectrum.
Here is the header of this image:
archive$templates/femtemp[20001][real]: FAST Emission line Template No bad pixels, min=unknown, max=unknown Line storage mode, physdim [20001], length of user area 1256 s.u. Created Tue 09:45:25 27-May-97, Last modified Tue 09:45:25 27-May-97 Pixel file "HDR$femtemp.pix" [ok] EXPTIME = 1. DISPAXIS= 1 DC-FLAG = 0 CRPIX1 = 1. CRVAL1 = 3000. CDELT1 = 0.25 W0 = 3000. WPC = 0.25 NP1 = 1 NP2 = 20001 VELOCITY= 0. BCV = 0. CHOPEM = F EMCHOP = F SUBCONT = F OVERLAP = T FRACPEAK= 0.7 ZEROPAD = T FI_FLAG = 3 EMLINE1 = ' MgII 2798.00 2798.00 20.00 2.90 0.00 0.00 145.38 1.000' EMLINE2 = ' OII 3727.30 3727.30 60.00 2.90 0.00 0.00 436.15 1.000' EMLINE3 = ' Hb 4861.33 4861.33 115.00 2.50 0.00 0.00 720.66 1.000' EMLINE4 = ' OIII 4958.91 4958.91 50.00 2.60 0.00 0.00 325.86 1.000' EMLINE5 = ' OIII 5006.84 5006.84 127.00 2.70 0.00 0.00 859.52 1.000' EMLINE6 = ' OI 6300.23 6300.23 32.00 2.40 0.00 0.00 192.51 1.000' EMLINE7 = ' N1 6548.06 6548.06 67.00 2.70 0.00 0.00 453.45 1.000' EMLINE8 = ' Ha 6562.82 6562.82 700.00 2.60 0.00 0.00 4562.06 1.000' EMLINE9 = ' N2 6583.57 6583.57 194.00 2.60 0.00 0.00 1264.34 1.000' EMLINE10= ' S1 6717.00 6717.00 132.00 2.70 0.00 0.00 893.36 1.000' EMLINE11= ' S2 6731.30 6731.30 100.00 2.70 0.00 0.00 676.79 1.000' HISTORY rvsao.linespec 2.0b 27-May-1997 09:45, 11 lines