The spatial extent and distribution of star formation in 3D-HST mergers at z ∼ 1.5

摘要: We present an analysis of the spatial distribution star formation in a sample 60 visually identified galaxy merger candidates at z > 1. Our sample, drawn from 3D-HST survey, is flux-limited and was selected to have high rates based on fits their broad-band, low resolution spectral energy distributions. It includes plausible pre-merger (close pairs) post-merger (single objects with tidal features) systems,with total stellar masses derived multi-wavelength photometry. Here we use near-infrared slitless spectra which produce H or [OIII] emission line maps as proxies for star-formation maps. This provides first comprehensive high-resolution, empirical picture where occurred mergers epoch peak cosmic rate. find that detectable can occur one both centres, tails. The most common case (58%) largely concentrated single, compact region, coincident centre (one of) components. No correlations between morphology redshift, mass, rate are found. A restricted set hydrodynamical simulations similarly massive gas-rich implies should be components, when gas fractions individual components same. suggests thatz 1:5 typically galaxies whose fractions, masses, and/or distinctly different another.