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We investigate the star formation main sequence (MS) (SFR-M$_{\star}$) down to 10$^{8-9}\mathrm{M}_\odot$ using a sample of 34,061 newly-discovered ultra-faint ($27\lesssim i \lesssim 30$ mag) galaxies at $1\sim27.9$ mag), blue (UV-slope $<\beta>\sim-1.9$), star-forming (rest-frame colors $\sim0.10$ mag, $\sim0.17$ mag) galaxies. These observational characteristics are identified with young (mass-weighted age $<\mathrm{t_{M-w}}>\sim0.014$ Gyr) stellar populations subject to low attenuations ($<\mathrm{A(V)}>\sim0.30$ mag). Our sample allows us to probe the MS down to $10^{8.0}\,\mathrm{M}_\odot$ at $z=1$ and $10^{8.5}\,\mathrm{M}_\odot$ at $z=3$, around 0.6 dex deeper than previous analysis. In the low-mass galaxy regime, we find an average value for the slope of 0.97 at $1

In this series of papers, we employ several machine learning (ML) methods to classify the point-like sources from the miniJPAS catalogue, and identify quasar candidates. Since no representative sample of spectroscopically confirmed sources exists at present to train these ML algorithms, we rely on mock catalogues. In this first paper, we develop a pipeline to compute synthetic photometry of quasars, galaxies, and stars using spectra of objects targeted as quasars in the Sloan Digital Sky Survey. To match the same depths and signal-to-noise ratio distributions in all bands expected for miniJPAS point sources in the range 17.5 ≤ r < 24, we augment our sample of available spectra by shifting the original r-band magnitude distributions towards the faint end, ensure that the relative incidence rates of the different objects are distributed according to their respective luminosity functions, and perform a thorough modelling of the noise distribution in each filter, by sampling the flux variance either from Gaussian realizations with given widths, or from combinations of Gaussian functions. Finally, we also add in the mocks the patterns of non-detections which are present in all real observations. Although the mock catalogues presented in this work are a first step towards simulated data sets that match the properties of the miniJPAS observations, these mocks can be adapted to serve the purposes of other photometric surveys.

In this series of papers, we employ several machine learning (ML) methods to classify the point-like sources from the miniJPAS catalogue, and identify quasar candidates. Since no representative sample of spectroscopically confirmed sources exists at present to train these ML algorithms, we rely on mock catalogues. In this first paper we develop a pipeline to compute synthetic photometry of quasars, galaxies and stars using spectra of objects targeted as quasars in the Sloan Digital Sky Survey. To match the same depths and signal-to-noise ratio distributions in all bands expected for miniJPAS point sources in the range $17.5\leq r<24$, we augment our sample of available spectra by shifting the original $r$-band magnitude distributions towards the faint end, ensure that the relative incidence rates of the different objects are distributed according to their respective luminosity functions, and perform a thorough modeling of the noise distribution in each filter, by sampling the flux variance either from Gaussian realizations with given widths, or from combinations of Gaussian functions. Finally, we also add in the mocks the patterns of non-detections which are present in all real observations. Although the mock catalogues presented in this work are a first step towards simulated data sets that match the properties of the miniJPAS observations, these mocks can be adapted to serve the purposes of other photometric surveys., Comment: 20 pages, 18 figures, submitted to MNRAS

In this series of papers, we employ several machine learning (ML) methods to classify the point-like sources from the miniJPAS catalogue, and identify quasar candidates. Since no representative sample of spectroscopically confirmed sources exists at present to train these ML algorithms, we rely on mock catalogues. In this first paper we develop a pipeline to compute synthetic photometry of quasars, galaxies and stars using spectra of objects targeted as quasars in the Sloan Digital Sky Survey. To match the same depths and signal-to-noise ratio distributions in all bands expected for miniJPAS point sources in the range $17.5\leq r<24$, we augment our sample of available spectra by shifting the original $r$-band magnitude distributions towards the faint end, ensure that the relative incidence rates of the different objects are distributed according to their respective luminosity functions, and perform a thorough modeling of the noise distribution in each filter, by sampling the flux variance either from Gaussian realizations with given widths, or from combinations of Gaussian functions. Finally, we also add in the mocks the patterns of non-detections which are present in all real observations. Although the mock catalogues presented in this work are a first step towards simulated data sets that match the properties of the miniJPAS observations, these mocks can be adapted to serve the purposes of other photometric surveys., Comment: 20 pages, 18 figures, submitted to MNRAS

© ESO 2018. We thank the anonymous referee for their detailed comments and suggestions to the original version of this manuscript, which helped to improve it considerably. Supported by the Ministerio de Economía y Competitividad del Gobierno de España (MINECO) under project AYA2012-31277 and project P3/86 of the Instituto de Astrofísica de Canarias. PGP-G acknowledges support from MINECO grants AYA2015-70815-ERC and AYA2015-63650-P. NCL acknowledges support from MINECO grants AYA2013-46724-P and AYA2016-75808-R. This work has made use of the Rainbow Cosmological Surveys Database, which is operated by the Universidad Complutense de Madrid (UCM) partnered with the University of California Observatories at Santa Cruz (UCO/Lick, UCSC). We are deeply grateful to the SHARDS team, since this work would not have been possible without their efforts. Based on observations made with the Gran Telescopio Canarias (GTC) installed at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, in the island of La Palma. This paper made use of R: A language and environment for statistical computing (R Core Team 2017, https://www.R-project.org/) and Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013, 2018). We thank all the GTC Staff for their support and enthusiasm with the SHARDS project. This work is based on observations taken by the 3D-HST Treasury Program (GO 12177 and 12328) with the NASA/ESA HST, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555., Context. Anti-truncated lenticular galaxies (Type-III S0s) present tight scaling relations between their surface brightness photometric and structural parameters. Although several evolutionary models have been proposed for the formation of these structures, the observations of Type-III S0 galaxies are usually limited to the local Universe. Aims. We aim to compare the properties of Type-III discs in a sample of S0 galaxies at 0.2 < z < 0.6with those of the local Universe. In this paper, we study the evolution of the photometric and structural scaling relations measured in the rest-frame R-band with z and the possible differences between the rest-frame (B - R) colours of the inner and outer disc profiles. Methods. We make use of a sample of 14 Type-III E/ S0-S0 galaxies at 0.2 < z < 0 : 6 from the GOODS-N field identified and characterised in a previous paper. We study whether or not the correlations found in local Type-III S0 galaxies were present similar to 6 Gyr ago. We analyse the distribution of the surface brightness characteristic parameters (R-break, mu(break), h(i), h(o), mu(0;) i and mu(0; o)) as a function of the stellar mass and look to see if there is a significant change with z. We also derive their rest-frame (B - R) colour profiles. Finally, we compare these results with the predictions from a grid of SSP models. Results. We find that the inner and outer scale-lengths of Type-III S0 galaxies at 0.4 < z < 0.6follow compatible trends and scaling relations with those observed in local S0 galaxies as a function of the break radius, R-break. We do not detect any significant differences between the location of R-break between z similar to 0.6 and z similar to 0 for a fixed stellar mass of the object, whereas the surface brightness at the break radius mu(break) is similar to 1.5 mag arcsec 2 dimmer in the local Universe than at z similar to 0.6 for a fixed stellar mass. We find no significant differences in the (B - R) colour between the inner and outer profi, Ministerio de Economía y Competitividad (MINECO), Instituto de Astrofísica de Canarias, 3D-HST Treasury Program, NASA/ESA HST under NASA, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

Type-III S0 galaxies present tight scaling relations between their surface brightness photometric and structural parameters. Several evolutionary models have been proposed for the formation of Type-III S0 galaxies but the observations of are usually limited to the local Universe. We study the evolution of the photometric and structural scaling relations found between the parameters of the surface brightness profiles in the rest-frame R-band of Type-III S0 galaxies with z and the possible differences between the rest-frame (B-R) colours of the inner and outer disc profiles. We make use of a sample of 14 Type-III E/S0--S0 galaxies at 0.2

Type-III S0 galaxies present tight scaling relations between their surface brightness photometric and structural parameters. Several evolutionary models have been proposed for the formation of Type-III S0 galaxies but the observations of are usually limited to the local Universe. We study the evolution of the photometric and structural scaling relations found between the parameters of the surface brightness profiles in the rest-frame R-band of Type-III S0 galaxies with z and the possible differences between the rest-frame (B-R) colours of the inner and outer disc profiles. We make use of a sample of 14 Type-III E/S0--S0 galaxies at 0.2