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Yafit can understand model data in a number of formats as written
by various spectral simulation codes. This list will probably need
to be expanded in the future. You can contact the author if a format
that you need is not here, but note that some well-defined description
of a format must be available in order for a handler to be written.
-
YModel
- YModel is the name given to the 'native' format used by Yafit for
model data. It is in fact a FITS or VOTable table in which each
row represents one model spectrum. The first column contains a vector
of X values, and the second a vector (of the same size) of Y values,
and these two therefore
together define a function Y(X) which represents the spectrum.
There may be any number of additional columns present,
giving other information about each model.
It is possible to write YModel files directly and to manipulate them
using TOPCAT or STILTS, but in most cases YModel files will be
written using the
copymodel
task.
-
Galaxev
- Spectra extracted into files by Galaxev's
galaxevpl
(a.k.a. gpl
) tool can be used.
These look something like this:
# Output file name = bc2003_hr_m42_salp_ssp_exp200.a1
# Input file name = bc2003_hr_m42_salp_ssp_exp200.ised
# Column 2 3 4
# Record 106 107 108
# Age (yr) 4.500E+07 4.750E+07 5.000E+07
# Lambda(A) Flux Flux Flux
9.100000E+01 6.685E-19 6.602E-19 6.520E-19
9.400000E+01 7.586E-19 7.491E-19 7.398E-19
...
-
Starburst99
- Output files written by the Starburst99 program
can be used. These look something like this:
MODEL DESIGNATION: eyles01100FM2
MODEL GENERATED ON 20060527 AT 035003.6
COMPUTED SYNTHETIC SPECTRUM
TIME [YR] WAVELENGTH [A] LOG TOTAL LOG STELLAR LOG NEBULAR [ERG/SEC/A]
.10000E+05 91.00 25.60479 25.60479 -15.00000
.10000E+05 94.00 26.34040 26.34040 -15.00000
...
-
SvoTar
- The Spanish Virtual Observatory (SVO) provides a service from the
web page http://svo.laeff.esa.es/theory/db2vo/html/
which returns grids of model spectra given certain criteria entered
in an HTML form. The result it returns is a tar archive containing
a number of VOTable files each of which holds a single calculated
spectrum. These tar files (compressed or uncompressed)
can be understood directly by Yafit as a list of model spectra.
-
SidewaysVOT
- This is an ad-hoc format which can be used to store model data in
a standard tabular format as a VOTable.
The first column of the table is used to
store X (wavelength) values, and each subsequent column stores
the Y (flux) values for a different model spectrum. All the Y values
in the Nth row correspond to the X value in that row and so on.
An M-column sideways table contains M-1 model spectra.
The only additional information about each spectrum is a name or label,
which is supplied by the column name of the column which it represents.
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