Identification and characterisation of emission line galaxies with J-PAS

The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) is expected to map thousands of square degrees of the northern sky with 56 narrow band filters (spectral resolution of R around 60) in the upcoming years. This resolution allows to study emission line galaxies (ELG) with equivalent widths of a few armstrongs. Meanwhile the Pathfinder J-PAS camera observed 1 deg^2 with the same photometric system than J-PAS, named the miniJPAS survey. In this work we identify and characterise a sample of emission line galaxies from miniJPAS with redshifts below 0.35 using a method based on artificial neural networks. By means of the WHAN and the BPT diagram we are able to determine its main ionisation mechanism. From the flux of H_alpha emission line, we characterise the star formation main sequence (SFMS) and we derive the cosmic evolution of the star formation rate density (rho_SFR) up to z=0.35.