Single photon x-ray detection with a CCD image sensor

Area of Science:

• Astrophysics
• Solid-state physics
• X-ray astronomy instrumentation

Background:

• X-ray astronomy relies on sensitive detectors for imaging and spectral analysis.
• Current detectors face limitations in spatial resolution and energy discrimination.
• Charge-coupled devices (CCDs) are widely used in digital imaging but their application in X-ray spectroscopy is an area of active research.

Purpose of the Study:

• To investigate the capability of individual pixels in a CCD image sensor to detect and perform energy analysis of individual X-rays.
• To evaluate the potential of CCDs as high-resolution, energy-discriminating sensors for X-ray astronomy.

Main Methods:

• Individual X-ray photons with energies of 5.9 keV and 22.4 keV were directed at a CCD image sensor.
• The energy of each detected X-ray was analyzed on a pixel-by-pixel basis.
• The spatial resolution and energy discrimination capabilities of the CCD pixels were assessed.

Main Results:

• The CCD image sensor successfully detected individual X-ray photons at specified energies.
• Each pixel of the CCD demonstrated the ability to discriminate the energy of the detected X-rays.
• The results confirm that CCDs function as an array of micro solid-state detectors.

Conclusions:

• CCD image sensors can serve as effective X-ray detectors with both high spatial resolution and energy discrimination capabilities.
• These findings highlight the suitability of CCDs for use as sensors at the focal plane of future X-ray telescopes.
• The demonstrated performance suggests a promising avenue for advancing X-ray astronomy instrumentation.