Acceptance Criteria.docx

XSD-CMS acceptance criteria for EIGER2S 9M for 12-ID-E

I. Acceptance for the EIGER2 S 9M for 12-ID-E The staff at 12-ID-E will independently verify the performance of the EIGER2 S 9M and determine if the product delivered by DECTRIS will be acceptable according to the criteria outlined in this document.

The staff will make a good faith attempt to complete those tests within 30 days of installation and certification by the vendor, provided there is delivered beam in the end station of this time. The results of these tests can be made available to the vendor. The vendor will have the right to repeat the test if the results are deemed unsatisfactory. The 12-ID-E staff reserves the right to refuse acceptance of the instrument in the event of failure of the acceptance testing. However, the 12-ID-E staff reserves the right to accept the detector even if its performance is less than specified. If the detector does not meet specifications, the contractor shall submit a "get well" plan that will show how future technological improvements will bring the detector up to the specifications in this contract. If the plan is acceptable to the 12-ID-E staff, the detector will be conditionally accepted based on the contractor implementing all future, relevant improvements to allow the detector to meet the specifications. Should it be determined that the detector cannot meet the contract specifications the 12-ID-E reserves the right to accept the detectors with a negotiated credit to the contract amount.

II. EIGER2 S 9M specifications

a. Detector specifications

b. Vacuum compatibility

III. Process for measuring detector parameters

a. Detector specifications 1 and 2. The active area and the gaps between modules will be determined as follows. A diffuse scatterer will be used to generate flood-field images. A fiducial plate in front of the detector will be used to calibrate the pixel spacing into mm. The calibration will allow the overall dimensions of the detector active area to be determined in units of mm. The gap between modules will calculated from these scaled images. Comparison to the detector area will provide the fractional gap between modules.

3. The vendor will provide a dead pixel map and a mask file to prevent dead pixels from being integrated and thereby compromising data quality. Flood field images with at least 100 counts per live-pixel will be recorded. The images will be analyzed and pixels with zero counts will be counted as dead and compared to the vendor provided dead pixel map. The dead pixel fraction will be calculated as the ratio of the dead pixels to the number of physical pixels.

4. The frame rate will be verified by recording flood-field and/or scattering images from glassy carbon using the vendor supplied software to request at least 200 sequential frames at rates of 1, 50 and 100 Hz. File header and file time stamp information will be used to verify the framing-rate.

5. Measuring the full dynamic range of the detector requires that one or more channels record 220 (1,048,576) counts while simultaneously one or more channels record zero counts. The maximum number of counts into a pixel can readily be achieved with a Silicon crystal. However, background scattering from the sample and beamline may not allow one to measure zero counts in a pixel (except for possible behind the beamstop). This can be overcome by masking part of the detector to block X-rays from reaching the detector so that some pixels see no X-rays.

6 and7. The maximum count rate and linearity of response of a pixel will be measured by using either a strongly scatterer (Silicon and/or glassy carbon) or a highly attenuated direct beam. Measurements will be made at several incident count rates between 1 kHz and 20 MHz. The incident count rate will be measured with a calibrated X-ray photon counting system. Deviation of the measured count rate from the incident count rate at 10^6 photons/sec/pixel should be less than 1% when proper consideration is given to undulator harmonics and particle beam timing mode.

8. The point spread function will be measured by placing a 5 – 20 micron diameter pin hole just in front of the detector to limit the beam size to significantly less than the dimensions of a pixel. The detector will be translated to center a pixel on the beam. Images at the centered location should only show counts in the centered pixel and not the neighboring pixels. The process will be repeated a few locations on the detector surface.

9. The Quantum Efficiency (QE) will be determined by recording the incident and measured intensities as described in 6 and 7 above at the specified energies. The QE = (measure counts)/(incident counts). Ratio of detected and incident photons will be calculated. Care must be taken to avoid harmonic contamination.

10. The uniformity among sensor modules will be verified by recording flood-field and/or scattering images and comparing signals between modules. The response difference between modules should be <5%.

11. Dark current or readout noise will be verified by collecting images without X-ray beam. The readout noise or dark current measured under no x-ray beam condition should be zero.

b. Vacuum compatibility This EIGER2 S 9M is engineered to being vacuum compatible. This will be tested by the manufacturer before delivery and a leak test certificate should accompany the detector as a part of its documentation. The detector will be housed in a medium vacuum flight tube that maintains a pressure of <5.0 x 10-3 mbar.

12. The detector performance will be verified at 1 atm and < 5x10^-3 mbar. The performance specified in 1-11 listed above should not significantly vary under 1 atm and < 5x10^-3 mbar.

13. The feedthrough parts provided by Dectris should be tested by the manufacturer and a leak test certificate should accompany the detector as a part of its documentation. Those parts will be tested on the vacuum flight tube. They should be able to maintain a pressure of <= 5.0 x 10-3 mbar for at least 2 days.