Parameters

The input parameters contained in make_catalog that are different from hyperz are:

• FILTERS_FILE: the name of the file containing in the first column the identification of filters and in the following columns the information needed to compute photometric errors, according to the error type selected by the parameter NOISE_TYPE. In this file lines beginning with a # are not considered.
• MODEL_CAT_FILE: the name of file that will contain the random catalogue obtained from the templates. Its format will be:
id, z, SpT, [$m(i),i=1,n_{\rm filt}$], $A_V$.
• NOISE_CAT_FILE: the name of file that will contain the random catalogue obtained from the MODEL_CAT_FILE adding a random noise. This is the simulated catalogue that can be used as photometric catalogue for hyperz. Its format will be:
id, [$m(i),i=1,n_{\rm filt}$], [$\Delta m(i),i=1,n_{\rm filt}$]
• REF_FILTER: the number of the filter (to be checked in the filters.log file) that will have a magnitude in the range between MAG_MIN and MAG_MAX.
• MAG_MIN and MAG_MAX: the magnitudes defining the range of apparent magnitudes attributed to the REF_FILTER.
• N_OBJ: the number of objects in the simulated catalogue.
• Z_FORM: the formation redshift of galaxies.
• Z_MIN and Z_MAX: the limits of the range of redshift where the redshift of the simulated galaxies z have to be selected.
• AGE_RANDOM: the option for the galaxy ages computation. Setting the value 0 the age is assumed to be equal to the age of a galaxy at the redshift z chosen randomly between Z_MIN and Z_MAX, taking into account that galaxy formation occurs at redshift Z_FORM. The value 1 produces ages of galaxies between 0 and the maximum value allowed according to Z_FORM.
• NOISE_TYPE: the type of noise adopted to compute the magnitudes in NOISE_CAT_FILE from MODEL_CAT_FILE: if NOISE_TYPE is 0, random noise with fixed sigma in magnitudes will be applied to magnitudes. Selecting 1, the noise $\Delta m$ will be computed as a function of $m$ following the approximation

$$\Delta m (m) \simeq\sqrt{\left[2.5 \log \left(1+\frac{1}{S/N}\right)\right]^2+{\tt ERR\_MAG\_MIN}^2} \:,$$ (4)

where $S/N$ is the signal to noise ratio, which is given as a function of the apparent magnitude through

$$S/N = (S/N)_0 10^{-0.4(m-m_0)}\: .$$ (5)

$(S/N)_0$ is the signal to noise ratio at a given reference magnitude $m_0$. In the case NOISE_TYPE = 0, in the file FILTERS_FILE the column two must correspond to the sigma of the errors distribution; in the second case the columns two and three are the value of $(S/N)_0$ and $m_0$ respectively. If you chose the latter option, during the run of the program, the limiting magnitudes in each filter will be showed. We assume as limiting magnitudes the value at which the signal to noise ratio fall down 1. You can use these magnitudes in the FILTERS_FILE for hyperz. The magnitudes exceeding the limiting magnitudes will be set to 99.
• ERR_MAG_MIN: this a kind of zeropoint error, added quadratically to the error estimate (see equation 4).

Here we report an example of the parameter files. The catalog.param file with all the parameters, and the filter's parameter file filter_UBVRI.param, with the two possible choices to compute the photometric noise:

::::::::::::::
catalog.param
:::::::::::::: 

A0VSED	~/ZPHOT/filters/A0V_KUR_BB.SED	# Vega SED
FILTERS_RES	~/ZPHOT/filters/FILTER.RES	# filters' transmission
FILTERS_FILE	filter_UBVRI.param	# filter's file
TEMPLATES_FILE	spectra1.param	# templates
MODEL_CAT_FILE	~/ZPHOT/models/UBVRI.model	# random catalogue
NOISE_CAT_FILE	~/ZPHOT/models/UBVRI.cat	# catalogue with noise
REF_FILTER	113	# reference filter
MAG_MIN	22.	# minimum apparent magnitude in REF_FILTER
MAG_MAX	25.	# maximum apparent magnitude in REF_FILTER
N_OBJ	1000	# number of objects
Z_FORM	10.	# formation redshift
Z_MIN	0.	# minimum redshift
Z_MAX	6.	# maximum redshift
AGE_RANDOM	0	# 0 age = age of universe - T(z_form)
		# 1 age = random between 0 and T(z)-T(z_form)
REDDENING_LAW	5	# reddening law
		# 0 no reddening
		# 1 Allen (1976) MW
		# 2 Seaton (1979) MW
		# 3 Fitzpatrick (1983) LMC
		# 4 Prevot (1984) Bouchet (1985) SMC
		# 5 Calzetti (2000)
AV_MIN	0.0	# minimum A_v
AV_MAX	1.2	# maximum A_v
NOISE_TYPE	1	# 0 random with fixed sigma in magnitudes
		# 1 dm(m)
ERR_MAG_MIN	0.05	# minimum error (if NOISE_TYPE=1)
H0	50.	# Hubble constant
OMEGA_M	1.	# density parameter (matter)
OMEGA_V	0.	# density parameter (Lambda)
RAND_SEED	3010	# seed for random generator (max 4 figures)

::::::::::::::
filter_UBVRI.param
:::::::::::::: 

# n.filter	sigma		(if NOISE_TYPE=0)
# 12	0.1
# 108	0.1
# 111	0.1
# 112	0.1
# 113	0.1
# n.filter	s/n	mag0	(if NOISE_TYPE=1)
12	10.	27.0
108	10.	27.5
111	10.	27.5
112	10.	27.5
113	10.	28.0

The UBVRI.cat have been shown in the previuos chapter, whereas the model catalog, containing the SED characteristics, looks like this example:

::::::::::::::
UBVRI.model
:::::::::::::: 

1	0.515	5	6.641	24.617	25.217	24.576	23.537	22.729	0.578
2	5.209	7	0.486	99.000	99.000	28.886	25.752	23.181	0.396
3	0.230	3	9.204	27.559	27.588	25.958	25.119	24.196	0.766
4	3.183	5	1.167	28.435	26.258	24.680	24.142	23.524	0.956
5	4.342	4	0.699	99.000	40.169	27.079	25.269	24.045	1.070

2000-12-10