The detector group at the Swiss Light Source at PSI has been one of the pioneers in the development of custom-made hybrid pixel array detectors (HPADs) for synchrotron applications. In a paper published recently [Jungmann-Smith et al. (2016). J. Synchrotron Rad. 23, 385-394; doi:10.1107/S1600577515023541], this group shows that it is now possible to develop HPADs with sufficient low noise to allow single-photon detection below 1 keV as well as to perform spectroscopic imaging. A commentary has also been written about the work [Graafsma (2016). J. Synchrotron Rad. 23, 383-384; doi:10.1107/S1600577516002721].
For decades, detectors have been a limiting factor in experiments at synchrotron radiation facilities. Even though imaging detectors evolved over time, the evolution of the source always outran the evolution of the detector. This situation started to change with the introduction of the so-called hybrid pixel array detectors, which contain a pixelated readout chip custom-designed for a well-defined experiment or technique.
One of the revolutionising advantages offered by this technology is that every single pixel contains all necessary electronics, including for instance counters, for X-ray detection. This massive parallelisation increased the overall efficiency of the detector by several orders of magnitude as compared with the charge-coupled-device-based system.
There are now various examples of HPADs, specifically developed for X-ray experiments at storage-ring synchrotron sources, as well as various spin-off companies commercialising them. Most of these systems are so-called photon-counting detectors, where each incoming photon is processed by the readout electronics in the pixel and individually counted.
The advantage of photon counting is that electronic noise, present in any system, can be efficiently discriminated against, yielding `noise-free' detectors. An application for such low-noise systems is in energy-dispersive measurements.
The researchers show in their paper that, with the use of a proper mask to shield the edge regions between pixels, very good fluorescence spectra can be obtained. This capability was subsequently used for multi-colour imaging at the SOLEIL synchrotron.
The innovative aspect of the work contained in this paper does not lie in the spectroscopic results obtained as they could very well have been obtained with other detectors. But what is truly impressive is that these results were obtained with an HPAD using a standard planar diode array as sensor.
This means that the system uses relatively standard and thus easy-to-manufacture components, making it possible to envision building larger and/or further-optimised systems in the near future. And with that, low-noise HPADs have entered a field formally reserved for silicon drift detectors and complementary metal-oxide semiconductor imagers.
Jonathan Agbenyega | EurekAlert!
Epoxy compound gets a graphene bump
14.11.2018 | Rice University
Automated adhesive film placement and stringer integration for aircraft manufacture
15.11.2018 | Fraunhofer IFAM
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
15.11.2018 | Earth Sciences
15.11.2018 | Physics and Astronomy
15.11.2018 | Physics and Astronomy