C1XS is a micro-technology demonstrator of a planetary X-ray spectrometer. It is based on the proven heritage of D-CIXS which successfully demonstrated the technological capabilities of this technique when it flew around the Moon on ESAs SMART-1 spacecraft. The accompanying X-ray Solar Monitor (XSM) will study the sun for changes in X-ray flux and X-ray spectrum emission and will be used to calibrate the C1XS lunar data.

The C1XS front end component consists of three facets, all looking in the same direction, with a defined 11 degree FOV (left). Each facet consists of 8 swept charge devices (SCD) X-ray detectors (see below). These detectors are based around e2v technology’s CCD54. Swept Charge Devices are a development on normal X-ray CCD sensors which require much less cooling and have a central read-out channel which takes the collected charge to single output amplifier circuit. The SCDs are mounted behind low profile gold/copper
collimators (a new technological innovation). This combination has the virtue of providing superior X-ray energy resolution in an instrument that is compact and low mass.

Detectors: 24 swept charge devices of 1 cm2 each
Energy range: 1 – 10 keV
Spectral resolution: <110 eV @ 6.4 keV (pre-launch calibration)
Ground Pixel: 25 km × 25 km FWHM
Mass: 5.7 kg
Power supply: 35 – 42 V
In-flight calibration: door mounted X-ray sources
Filters: Al filters used to block sunlight
Elemental Range: Mg, Al, Si, Ca (Ti, Fe)

XSM Detector: Si-PIN
Energy range: 1 – 20 keV
Spectral resolution: ~200 eV @ 6 keV (pre-launch calibration)
FOV: 105°