SWAP (Sun Watcher with Active Pixels and Image Processing) is a single-band EUV telescope which observes the solar corona in a passband centered on 17.4 nm and with a 54×54 arcmin FOV, has a novel off-axis Ritchey–Chretien design with two mirrors with multilayer coatings for EUV reflectivity and a complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS). A scintillator coating (P43) converts EUV photons into visible photons to which the detector is sensitive. Spectral selection is achieved by the combination of multilayer coatings and two Al-foil filters, one of which is located at the entrance aperture and the other in front of the focal-plane assembly.
SWAP has operated essentially continuously since shortly after PROBA2’s injection into its polar Sun-syn chronous orbit in November 2009 at an approximate altitude of 725 km.
- Characterisation of the HAS detector (SWAP) at DeMeLab
- SWAP instrument calibration (PTB/BESSY II)