Proton (blue symbols) and helium (magenta symbols) energy spectra during the time period from 13 to 17 UT as measured by the STEREO SIT (Mason et al. 2008). In comparison the black and dark magenta lines show our results from analyzing SEPT measurements. Here, the solid lines represent the part of the fitted spectra that contributes to all SEPT channels. The part marked by the dashed lines contributes to the proton channels only.