Nebular and stellar properties of a metal poor HII galaxy at z=3.36
  We have characterized the physical properties (electron temperature, density, metallicity) of the ionized gas and the ionizing population (age, metallicity, presence of WR stars) in the Lynx arc at z=3.36. This is a low metallicity (~10% solar) HII galaxy which is undergoing a burst of star formation of <5 Myr age. One possible scenario that explains the emission line spectrum of the Lynx arc, the large strength of the nitrogen lines and the HeII emission is that the object has experienced a merger event that has triggered a burst of star formation. WR stars have formed that contribute to a fast enrichment of the ISM and its overabundance of nitrogen. 
Montse Villar-Martin, Miguel Cervino, Rosa Gonzalez Delgado (IAA-CSIC,   Spain)