High-resolution soft x-ray spectrometry using the electron-multiplying charge-coupled device (EM-CCD)

David J. Hall; James H. Tutt; Matthew R. Soman; Andrew D. Holland; Neil J. Murray; Bernd Schmitt; Thorsten Schmitt

doi:10.1117/12.2024010

Translator Disclaimer

26 September 2013 High-resolution soft x-ray spectrometry using the electron-multiplying charge-coupled device (EM-CCD)

David J. Hall, James H. Tutt, Matthew R. Soman, Andrew D. Holland, Neil J. Murray, Bernd Schmitt, Thorsten Schmitt

Author Affiliations +

Proceedings Volume 8859, UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XVIII; 88590H (2013) https://doi.org/10.1117/12.2024010
Event: SPIE Optical Engineering + Applications, 2013, San Diego, California, United States

Abstract

The Electron-Multiplying Charge-Coupled Device (EM-CCD) shares a similar structure to the CCD except for the inclusion of a gain register that multiplies signal before the addition of read-noise, offering sub-electron effective readnoise at high frame-rates. EM-CCDs were proposed for the dispersive spectrometer on the International X-ray Observatory (IXO) to bring sub-300 eV X-rays above the noise, increasing the science yield. The high-speed, low-noise performance of the EMCCD brought added advantages of reduced dark current and stray-light per frame, reducing cooling and filtering requirements. To increase grating efficiency, several diffracted spectral orders were co-located so the inherent energy resolution of the detector was required for order separation. Although the spectral resolution of the EM-CCD is degraded by the gain process, it was shown that the EM-CCD could achieve the required separation. The RIXS spectrometer at the Advanced Resonant Spectroscopy beamline (ADRESS) of the Swiss Light Source (SLS) at the Paul Scherrer Institute currently uses a CCD, with charge spreading between pixels limiting the spatial resolution to 24 μm (FWHM). Through improving the spatial resolution below 5 μm alongside upgrading the grating, a factor of two energy resolution improvement could theoretically be made. With the high-speed, low-noise performance of the EM-CCD, photon-counting modes could allow the use of centroiding techniques to improve the resolution. Using various centroiding techniques, a spatial resolution of 2 μm (FWHM) has been achieved experimentally, demonstrating the benefits of this detector technology for soft X-ray spectrometry. This paper summarises the use of EM-CCDs from our first investigations for IXO through to our latest developments in ground-based testing for synchrotron-research and looks beyond to future possibilities.

Citation Download Citation

David J. Hall, James H. Tutt, Matthew R. Soman, Andrew D. Holland, Neil J. Murray, Bernd Schmitt, and Thorsten Schmitt "High-resolution soft x-ray spectrometry using the electron-multiplying charge-coupled device (EM-CCD)", Proc. SPIE 8859, UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XVIII, 88590H (26 September 2013); https://doi.org/10.1117/12.2024010

ACCESS THE FULL ARTICLE