Temperature and density in coronal holes-results from CDS/SOHO

The high speed solar wind stream comes from coronal hole regions, and it is thought that non-plume areas may provide the dominant contribution. Constraints on density and temperature in these regions are extremely important for understanding the heating and acceleration of the solar wind. Measurements are presented here from the Coronal Diagnostic Spectrometer (CDS) on SOHO, which can resolve spectral and spatial dimensions and so allow the study of individual features on the solar surface.