Parameters¶
If one needs a new config file, run the following script;
python get_configfile.py
Paramter Description¶
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 | int | Minimization method in lmfit. For initial values. 0=Powell, 1=Nelder (faster). |
| ZVIS | int | Visual inspection of redshift. 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 | Profile shape, if grism spectra are provided. Will be used to convolve templates. “moffat”, “gauss”, or none. |
| MORP_FILE | str | Ascii file for morphology parameters. |
| VDISP | float | Velocity dispersion in km/s. Will be used to convolve templates if MORP=none. |
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. |
| ADD_LINES | int | If 1, emission lines will be added to spectral templates. 0=no, 1=yes. Only supported for fsps. |
| LOGU | float | Ionizing parameter U, in log, only effective when ADD_LINES==1. |
| 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 if ZFIX is provided). |
| AMAX | str | (Optional) Maximum value for amplitude, in normal logarithmic scale. |
| AMIN | str | (Optional) Minimum value for amplitude, in normal logarithmic scale. |
| 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. |
| 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. |
| BPASS | int | If 1, BPASS templates will be used. Currently not supported. |
Parameters for a specific 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> <Executing-flag> –id <ID>). |
| ZGAL | float | Initial guess of source redshift. You can skip this if “redshift” column is included in CAT_BB. |
| CZ0 | float | Initial guess of spectral normalization for G102. |
| CZ1 | float | Initial guess of spectral normalization for G141. |
Parameters for far-infrared components (Support starts 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 | Directory for FIR templates. |
Parameters for functional-form SFHs (Support starts from version1.4)
| 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. |