Towards a configuration for the Southern Wide-field Gamma-ray Observatory (SWGO) outer array

The Southern Wide-field Gamma-ray Observatory (SWGO) is proposed as a next-generation ground-based water Cherenkov detector array designed to study Very High-Energy gamma-rays. It will be located in the Atacama Astronomical Park in Chile, at 4770 m above sea level, with a direct view of the Galactic Center and the Southern Sky. The proposed SWGO array will consist of an inner high-density core (>60%) and an outer array with lower fill factor (<5%) devoted to the detection of the highest energy events. Various possible choices for the water-Cherenkov detector units, photosensors and electronics, together with the array layout, are being explored. Rotomolded HDPE tanks are considered as a viable alternative to steel tanks together with several configurations, in number and placement, of photosensor units. In this contribution the most promising options will be presented based on the ongoing optimization studies.