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(Abridged) In a recent work we explored the dependence of galaxy stellar population properties derived from broad-band spectral energy distribution fitting on the fitting parameters, e.g. SFHs, age grid, metallicity, IMF, dust reddening, reddening law, filter setup and wavelength coverage. In this paper we consider also redshift as a free parameter in the fit and study whether one can obtain reasonable estimates of photometric redshifts and stellar population properties at once. We use mock star-forming as well as passive galaxies placed at various redshifts (0.5 to 3) as test particles. Mock star-forming galaxies are extracted from a semi-analytical galaxy formation model. We show that for high-z star-forming galaxies photometric redshifts, stellar masses and reddening can be determined simultaneously when using a broad wavelength coverage and a wide template setup in the fit. Masses are similarly well recovered (median ~ 0.2 dex) as at fixed redshift. For old galaxies with little recent star formation masses are better recovered than in the fixed redshift case, such that the median recovered stellar mass improves by up to 0.3 dex whereas the uncertainty in the redshift accuracy increases by only ~ 0.05. However, a failure in redshift recovery also means a failure in mass recovery. As at fixed redshift mismatches in SFH and degeneracies between age, dust and now also redshift cause underestimated ages, overestimated reddening and underestimated masses. Stellar masses are best determined at low redshift without reddening in the fit (median underestimation ~ 0.1 dex for similarly well recovered redshifts). Not surprisingly, the recovery of properties is substantially better for passive galaxies. In all cases, the recovery of physical parameters is crucially dependent on the wavelength coverage adopted in the fitting. Scaling relations for the transformation of stellar masses are provided.
Context. NRAO 150 is one of the brightest radio and mm AGN sources on the northern sky. It has been revealed as an interesting source where to study extreme relativistic jet phenomena. However, its cosmological distance has not been reported so far,
We compile multi-wavelength data from ultraviolet to infrared (IR) bands as well as redshift and source-type information for a large sample of 178,341 sources in the Hawaii-Hubble Deep Field-North field. A total of 145,635 sources among the full samp
We have developed an analytical method to investigate the stellar populations in a galaxy using the broad-band colours. The method enables us to determine the relative contribution, spatial distribution and age for different stellar populations and g
Our aim in this work is to answer, using simulated narrow-band photometry data, the following general question: What can we learn about galaxies from these new generation cosmological surveys? For instance, can we estimate stellar age and metallicity
We investigate a new method to recover (if any) a possible varying speed of light (VSL) signal from cosmological data. It comes as an upgrade of [1,2], where it was argued that such signal could be detected at a single redshift location only. Here, w