Data Quality

SAXS data interpretation is tough

Interpreting SAXS data is very often about coaxing structural information from loosely organized materials that scatter only weakly….using everything you previously knew about your sample to establish a conceptual model …and then refining the physical parameters of the model to agree with the SAXS data.

Even in cases where the basic signal is strong, researchers will go to the limit of the data integrity to pull out additional structural information: “Nice to know the average particle size, but what I’d really like to know is the distribution!”, “Knowing the average structural repeat distance is fine … but what about the correlation length?”

Data quality is #1

Given this nature of SAXS and the researchers using it, data-quality is obviously one of the most important evaluation criteria for any SAXS instrument.

The things one does

So, at SAXSLAB we have designed our instruments to provide you with the very best data quality possible, which has required

  • Maximizing the available X-ray flux
  • Providing the best resolution for any given choice of x-ray flux
  • Minimizing the noise and background level

These criteria are achieved by

  • exclusively using high brilliance micro-focus x-ray sources, so that the highest combination of flux and resolution can be achieved
  • using a quasi-focusing multilayer monochromator, that keeps the x-rays collimated within a narrow cone
  • employing the scatterless blade geometry, which inherently increases the available flux for any qmin
  • operating under vacuum and removing all unnecessary windows from the source to the detector, so that as few x-rays as possible are absorbed or scattered
  • and finally using a detector with an efficiency of ~ 100% and single-pixel point-spread function, so that no x-ray is left unaccounted for and each x-ray gets registered, where it first lands

And the things we do…extra

Now admittedly, most instrument manufacturers are doing these things…because they make sense and the required high end components are readily available…but where we really believe we differentiate ourselves from the rest, is our attention to minimizing the noise and the background, which we do by:

  • Employing proprietary pattern recognition software to recognize and remove cosmic background in the detector images.
  • Placing our detector INSIDE the vacuum chamber, in order to minimize absorption and scattering from windows separating the vacuum from the detector, as well as assist in blocking a significant proportion of the cosmic background radiation.

In this way, we achieve a reduction of a factor of 15 in the “natural” unavoidable cosmic background, which in terms of data-quality for weakly scattering systems is equivalent to a very costly factor of 15 increase in intensity.

We are committed to data quality

As we strive to provide our customers with the very best SAXS instrumentation available, you can rest assured that we will continue to lead the field in the drive towards ever better data-quality.