FFIT
Solves for T, theta, E(B-V) for one or two stars by fitting theoretical flux distributions to observed fluxes and/or photometry.Input file structure:
command
or
command{ subcommand [ subcommand [ parameter [...]]] }
or
command subcommand [ subcommand [ parameter [...]]] end_command
- In general lines can be broken anywhere, but there are some exceptions.
- Strings beginning ! are treated as comments and ignored.
- Some commands can be broken up and/or placed in any order, but others (models and wavelength) must appear in order at the start of the input.
Command Summary
models sets up model spectrum grid adjusts model wavelength grid parameters initialize spectrum fit parameters method select solution method data input observational data solve pursue solution by interpolation in grid end finish gracefully
Example 1. Fit Teff, theta and E(B-V) to IUE spectrum and uvby photometry using a grid of helium-rich model flux distributions.
models{
2
t01980001 Helium-rich constant g
11 1 1
0 0 0
/sim../../models/01980001/19325he90L.s
/sim../../models/01980001/20325he90L.s
/simon/models/01980001/21325he90L.s
/sim../../models/01980001/22325he90L.s
/simon/models/01980001/23325he90L.s
/sim../../models/01980001/24325he90L.s
/simon/models/01980001/25325he90L.s
/sim../../models/01980001/26325he90L.s
/simon/models/01980001/27325he90L.s
/sim../../models/01980001/28325he90L.s
}!---! define model spectrum grid
! file format specifier
! grid title
! grid dimensions
! grid wavelength (use defaults)
! grid filenames
wavelengths{
iue
phot 4 uvby
}!---! define photmetric system
! use standard IUE wavelength range
! use Stromgren magnitudesparameters{
3
20.0 1.0 'Teff kK'
0.03 0.01 'Ebv'
3.0E-11 0.5E-11 'theta'
}data{
folder .
iue 059x.sp2
phot 10.487 10.516 10.501 10.559
errors 0.03 0.03 0.03 0.001
}!---! read spectrum to fit
! data in current folder
! IUE data file in "spectrum format 2"
! uvby magnitudes
! uvby errors (in mag.)solve
end! compute a solution
This page is maintained by:
Simon Jeffery (csj@star.arm.ac.uk)
Last modified: 06/06/01