2019A&A...621A..52L


Query : 2019A&A...621A..52L

2019A&A...621A..52L - Astronomy and Astrophysics, volume 621A, 52-52 (2019/1-1)

Star-forming galaxies at low-redshift in the SHARDS survey.

LUMBRERAS-CALLE A., MUNOZ-TUNON C., MENDEZ-ABREU J., MAS-HESSE J.M., PEREZ-GONZALEZ P.G., ALCALDE PAMPLIEGA B., ARRABAL HARO P., CAVA A., DOMINGUEZ SANCHEZ H., ELICHE-MORAL M.C., ALONSO-HERRERO A., BORLAFF A., GALLEGO J., HERNAN-CABALLERO A., KOEKEMOER A.M. and RODRIGUEZ-MUNOZ L.

Abstract (from CDS):


Context. The physical processes driving the evolution of star formation (SF) in galaxies over cosmic time still present many open questions. Recent galaxy surveys allow now to study these processes in great detail at intermediate redshift (0≤z≤0.5).
Aims. We build a complete sample of star-forming galaxies and analyze their properties, reaching systems with low stellar masses and low star formation rates (SFRs) at intermediate-to-low redshift.
Methods. We use data from the SHARDS multiband survey in the GOODS-North field. Its depth (up to magnitude <m≳26.5) and its spectro-photometric resolution (R∼50) provides us with an ideal dataset to search for emission line galaxies (ELGs). We develop a new algorithm to identify low-redshift (z<0.36) ELGs by detecting the [OIII]5007 and Hα emission lines simultaneously. We fit the spectral energy distribution (SED) of the selected sample, using a model with two single stellar populations.
Results. We find 160 star-forming galaxies for which we derive equivalent widths (EWs) and absolute fluxes of both emission lines. We detect EWs as low as 12Å, with median values for the sample of ∼35Å in [OIII]5007 and ∼56Å in Hα, respectively. Results from the SED fitting show a young stellar population with low median metallicity (36% of the solar value) and extinction (AV∼0.37), with median galaxy stellar mass ∼108.5M. Gas-phase metallicities measured from available spectra are also low. ELGs in our sample present bluer colours in the UVJ plane than the median colour-selected star-forming galaxy in SHARDS. We suggest a new V-J colour criterion to separate ELGs from non-ELGs in blue galaxy samples. In addition, several galaxies present high densities of O-type stars, possibly producing galactic superwinds, which makes them interesting targets for follow-up spectroscopy.
Conclusions. We have demonstrated the efficiency of SHARDS in detecting low-mass ELGs (∼2 magnitudes deeper than previous spectroscopic surveys in the same field). The selected sample accounts for 20% of the global galaxy population at this redshift and luminosity, and is characterized by young SF bursts with sub-solar metallicities and low extinction. However, robust fits to the full SEDs can only be obtained including an old stellar population, suggesting the young component is built up by a recent burst of SF in an otherwise old galaxy.

Abstract Copyright: © ESO 2019

Journal keyword(s): galaxies: star formation - galaxies: photometry - galaxies: fundamental parameters - galaxies: stellar content - galaxies: starburst

Simbad objects: 8

goto Full paper

goto View the references in ADS

Number of rows : 8
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2022
#notes
1 NAME SMC G 00 52 38.0 -72 48 01   2.79 2.2     ~ 10317 1
2 NAME Magellanic Clouds GrG 03 00 -71.0           ~ 6373 1
3 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 16158 1
4 NAME 30 Dor Nebula SFR 05 38 36.0 -69 05 11           ~ 1114 2
5 RMC 136 Cl* 05 38 42.396 -69 06 03.36           ~ 1872 1
6 NAME Sex A H2G 10 11 00.5 -04 41 30 12.48 12.13 11.93 11.78   ~ 692 2
7 NAME Hubble Deep Field reg 12 36 49.5 +62 12 58           ~ 1877 1
8 NAME GOODS-N Field reg 12 36 55.0 +62 14 15           ~ 1038 1

To bookmark this query, right click on this link: simbad:objects in 2019A&A...621A..52L and select 'bookmark this link' or equivalent in the popup menu


2022.08.15-14:21:25

© Université de Strasbourg/CNRS

    • Contact