Paramter Description

All parameters of gsf can be specified in the configuration file with the following columns. An example config file can be generated by executing the following command (TBD);

python example/get_configfile.py [name-of-config-file]

Parameters for the fitting step:

Parameter	Type	Description
NMC	int	No. of iterations for the primary MCMC step.
NWALK	int	No. of walkers for the primary MCMC step.
NMCZ	int	No. of iterations for the pre-redshift fitting step.
NWALKZ	int	No. of walkers for the pre-redshift fitting step.
FNELD	str	Minimization method with lmfit, to configure initial parameters. powell, nelder (faster), etc. The whole list can be found here.
ZVIS	int	Visual inspection of redshift fit. 1=yes, 0=no. If you are not confident with input values (ZGAL, CZ0, CZ1), then this should be set to 1 for iterative fit.

Parameters for input data:

Parameter	Type	Description
DIR_OUT	str	Directory for output products. If not exist, gsf will create one.
DIR_TEMP	str	Directory for spectral templates to be stored. If not exist, gsf will create one.
CAT_BB	str	Broadband photometry catalog. Read ‘’ for its format.
DIR_FILT	str	Directory for filter response curve files.
FILTER	str	Filters of broadband photometry. Comma-separated string, where each string should match *.fil files in DIR_FILT.
SKIPFILT	str	List of filters that are skipped in the fitting (e.g., for IRAC excess). Comma-separated string.
SNLIM	int	SN limit for data points. If the SN is below this, then eflux of the data point is used as an upper limit.
DIR_EXTR	str	Directory for spectroscopic data. If none, gsf will ignore and fit only to broadband data.
SPEC_FILE	str	Comma separated list for spectral files. Path is relative to DIR_EXTR.
MORP	str	“moffat”, “gauss”, or none. Profile shape, if grism spectra are provided. Will be used to convolve templates.
MORP_FILE	str	Ascii file for morphology parameters.
VDISP	float	Velocity dispersion in km/s. Will be used to convolve templates if MORP=none.
MAGZP	float	magnitude zeropoint of CAT_BB. Default 25.0. For Jy, use 8.9. For microJy 23.9.

Parameters for spectral templates:

Parameter	Type	Description
AGE	str	Set of age pixels, lookback time, in Gyr. Comma-separated.
AGEFIX	str	(Optional) Subset of age pixels that are used in fitting. Lookback time, in Gyr. Comma-separated.
TAU0	int	Length for star formation of each age pixel, in Gyr (0.01 to 20Gyr). If 99, CSP is applied. If negative, SSP is applied.
NIMF	int	Choice of IMF. 0=Salpeter, 1=Chabrier, 2=Kroupa, 3=van Dokkum, 4=Dave, 5=tabulated, specified in imf.dat.
ZMAX	float	Maximum value for metalicity, in logZ.
ZMIN	float	Minimum value for metalicity, in logZ.
DELZ	float	Resolution for metallicity, in logZ.
ZFIX	float	(Optional) Metallicity will be fixed to this value if specified. In logZ.
ZEVOL	int	(Optional) If 1, metallicity for each age pixel will be set as a free parameter. If not, metallicity will be universal to all age pixels (or fixed to ZFIX if provided).
AMAX	str	(Optional) Maximum value for amplitude, in normal logarithmic scale.
AMIN	str	(Optional) Minimum value for amplitude, in normal logarithmic scale.
DUST_MODEL	int	Dust attenuation model (default 0). 0 for Calzetti. 1 for MW. 2 for LCM. 3 for SMC. 4 for Kriek & Conroy (2013).
AVMAX	float	(Optional) Maximum value for Av (dust attenuation in V-band), in mag.
AVMIN	float	(Optional) Minimum value for Av (dust attenuation in V-band), in mag.
F_ZMC	int	If 1, redshift is set as a free parameter in the primary MCMC step. Otherwise, redshift is fixed to the input parameter.
F_MDYN	int	If 1, gsf uses dynamical mass (M_dyn column in CAT_BB) as a prior. Currently not supported.
ADD_NEBULAE	int	If 1, gsf adds nebular emission lines calculated within fsps.
logUMAX	float	Maximum value for ionization parameter, in log, for emission lines if ADD_NEBULAE is True.
logUMIN	float	Minimum value for ionization parameter, in log, for emission lines if ADD_NEBULAE is True.
DELlogU	float	Resolution for logU.
logUFIX	float	(Optional) logU will be fixed to this value if specified.
BPASS	int	If 1, BPASS templates will be used. Currently not supported.

Read Redshift Fitting for a caveat about making redshift a free parameter.

Parameters specific for the target:

Parameter	Type	Description
ID	str	Target ID. You can also specify this by adding “–id” argment (i.e. python run_gsf.py <config_file> <Execution-flag> –id <ID>).
ZMC	float	Initial guess of source redshift. You can skip this if “redshift” column is included in CAT_BB.
ZMCMIN	float	Minimum value for ZMC.
ZMCMAX	float	Maximum value for ZMC.
CZ0	float	Initial guess of spectral normalization for G102.
CZ1	float	Initial guess of spectral normalization for G141.

Parameters for functional-form SFHs:

Parameter	Type	Description
SFH_FORM	int	1: Tau-model, 4: Delayed tau-model, 5: Delayed tau-model with a transition, based on fsps.
NPEAK	int	Number of components for SFHs combined. (e.g., if 2, then two of SFH_FORM will be combined.)
AGEMAX	float	Maximum age for the functional form SFH, in log Gyr.
AGEMIN	float	Minimum age for the functional form SFH, in log Gyr.
DELAGE	float	Delta age for the age parameter, in log Gyr.
TAUMAX	float	Maximum tau for the functional form SFH, in log Gyr.
TAUMIN	float	Minimum tau for the functional form SFH, in log Gyr.
DELTAU	float	Delta age for the tau parameter, in log Gyr.

Parameters for far-infrared components: (Beta implimentation from version1.4)

Parameter	Type	Description
FIR_FILTER	str	Filters of FIR photometry. Comma-separated string, where each string should match *.fil files in DIR_FILT.
CAT_BB_DUST	str	Directory for the FIT photometric catalog, in the same format as for CAT_BB.
TDUST_HIG	float	Maximum temperature.
TDUST_LOW	float	Minimum temperature.
TDUST_DEL	float	Delta T for temperature paramter, in Kelvin.
DIR_DUST	str	Path to the directory where FIR templates are stored.