Detectors
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Francesco
Guzzi
,
Alessandra
Gianoncelli
,
Luigi
Stebel
,
Dario
Giuressi
,
Giuseppe
Cautero
,
Roberto
Borghes
,
Iztok
Gregori
,
Fulvio
Billè
,
Martin
Scarcia
,
Valentina
Bonanni
,
Milan
Žižić
,
Hyojung
Hyun
,
William
Nichols
,
Jonathan
Correa
,
Alessandro
Marras
,
Corenelia B.
Wunderer
,
Heinz
Graafsma
,
Ralf Hendrik
Menk
,
George
Kourousias
Open Access
Abstract: PERCIVAL is a novel soft X-ray detection system designed for the needs of modern microscopy. By integrating it into the TwinMic end-station at Elettra Sincrotrone Trieste, we conducted an exploratory computational microscopy experiment on biological samples, aiming at evaluating the entire system in a real use-case scenario. We present the methodology to convert the RAW data and our high-resolution image reconstructions.
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Jan 2025
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B16-Test Beamline
Detectors
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M. J.
Basso
,
E.
Buchanan
,
B. J.
Gallop
,
J. J.
John
,
J.
Kaplon
,
P. T.
Keener
,
P. W.
Phillips
,
L.
Poley
,
C. A.
Sawyer
,
D.
Sperlich
,
M.
Warren
Diamond Proposal Number(s):
[28368]
Open Access
Abstract: The front-end electronics of silicon detectors are typically designed to ensure optimal noise performance for the expected input charge. A combination of preamplifiers and shaper circuits result in a nontrivial response of the front-end to injected charge, and the magnitude of the response may be sizeable in readout windows subsequent to that in which the charge was initially injected. The modulation of the discriminator threshold due to the superposition of the front-end response across multiple readout windows is coined "threshold bounce". In this paper, we report a measurement of threshold bounce using silicon modules built for the Phase-II Upgrade of the ATLAS detector at the Large Hadron Collider. These modules utilize ATLAS Binary Chips for their hit readout. The measurement was performed using a micro-focused 15 keV photon beam at the Diamond Light Source synchrotron. The effect of the choice of photon flux and discriminator threshold on the magnitude of the threshold bounce is studied. A Monte Carlo simulation which accounts for the front-end behaviour of the silicon modules is developed, and its predicted hit efficiency is found to be in good agreement with the measured hit efficiency.
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Jun 2024
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Detectors
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Open Access
Abstract: The scintillation properties of cesium-zirconium hexachloride (Cs2ZrCl6) were investigated by γ-ray spectrometry and the Compton Coincidence Technique. The tested cylindrical sample had 20 mm diameter and 12 mm height. The crystal shows a high light output of 40 900 photons per MeV as measured by a spectroscopy type photomultiplier with 20 μs pulse integration time under γ-ray excitation at room temperature. A small deviation from linear response as a function of energy deposited in γ-ray absorption or Compton scattering processes, combined with a high light yield, results in good energy resolution equal to 4.3 % at 662 keV and 2.3 % at 2.6 MeV. Due to long lasting scintillation decay the sample properties were studied at different shaping time constants in an analogue spectroscopy chain or using different integration time gates when employing a digital analyzer.
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Dec 2023
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Detectors
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Abstract: A non-destructive CVD diamond X-ray beam imaging monitor has been developed for synchrotron beamlines. The device can be permanently installed in the X-ray beam path and is capable of transmissively imaging the beam profile at 100 frames per second. The response of this transmissive detector at this imaging rate is compared to synchronously acquired images using a destructive fluorescent screen. It is shown that beam position, size, and intensity measurements can be obtained with minimal disturbance to the transmitted X-ray beam. This functionality is beneficial to synchrotron beamlines as it enables them to monitor the X-ray beam focal size and position in real-time, during user experiments. This is a key enabling technology that would enable live beam size feedback, keeping the beamline’s focusing optics optimised at all times. Ground vibrations (10 Hz - 20 Hz) can cause movement of focusing optics and beamline mirrors, which disturb the X-ray beam and reduce the ultimate quality of the sample-point beam. This instrument can detect this beam motion, enabling the source to be more easily determined and mitigations to be put in place.
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Oct 2023
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I22-Small angle scattering & Diffraction
Detectors
Diagnostics
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Open Access
Abstract: Single-crystal chemical vapour deposition (CVD) diamond detectors are an established transmissive synchrotron beamline diagnostic instrument used for beam position and beam intensity monitoring. A recently commercialized alternative is silicon carbide (4H-SiC) devices. These have the potential to provide the same diagnostic information as commercially available single-crystal CVD diamond X-ray beam position monitors, but with a much larger transmissive aperture. At Diamond Light Source an experimental comparison of the performance of single-crystal CVD diamond and 4H-SiC X-ray beam position monitors has been carried out. A quantitative comparison of their performance is presented in this paper. The single-crystal diamond and 4H-SiC beam position monitors were installed in-line along the synchrotron X-ray beam path enabling synchronous measurements at kilohertz rates of the beam motion from both devices. The results of several tests of the two position monitors' performance are presented: comparing signal uniformity across the surface of the detectors, comparing kHz intensity measurements, and comparing kHz beam position measurements from the detectors. Each test is performed with a range of applied external bias voltages. A discussion of the benefits and limitations of 4H-SiC and single-crystal CVD diamond detectors is included.
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Sep 2023
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Detectors
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Abstract: The MerlinEM/Medipix3 is a versatile detector widely used for scanned electron diffraction, precession, dynamic transmission electron microscopy (TEM) and scanning transmission electron microscopy (4D STEM). It can be used to image direct probes (up to 300kV) while still retaining the ability to count single electrons for the weaker diffraction spots [1]. It contains two 12-bit counters, enabling zero dead time acquisitions and noiseless readout. This makes MerlinEM an attractive solution for low-dose techniques in many areas of electron microscopy.
We are particularly interested in the application of micro electron diffraction (3DED, microED) techniques for structure determination of small molecules of biological and pharmaceutical importance [2]. 3DED has been growing in popularity in recent years thanks to the development of more sensitive detectors and stable automated diffraction setups. Electron diffraction has the essential advantage over X-ray crystallography when crystal size is concerned. It produced multiple medium to high resolution structures from nano crystals and from artificially thinned (by focused ion beam milling) crystals [3, 4]. Furthermore, electrons have an advantage over X-rays as they interact orders of magnitude more strongly with samples. This allows hydrogen atoms to be located within the structure to gain insights into the chemical properties of small compounds. This is essential in chemical research, pharmaceutical drug discovery and other industries [5]. Furthermore, performing electron diffraction tomography on multiple crystals in an automated manner enables efficient collection of large datasets. For this reason, we worked closely with the team at Quantum Detectors. A recently available plugin for MerlinEM to the academic SerialEM software environment [6] has enabled low-dose 3DED data collections on the MerlinEM Quad 4S installed on the FEI Tecnai F30 cryo electron microscope at the Rosalind Franklin institute. We present data obtained on small compounds of pharmaceutical interest by HeXI at Diamond Light Source using 3DED with MerlinEM.
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Aug 2023
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Detectors
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Abstract: A heterogeneous Image acquisition and processing system is presented based on commercially available components. Due to the addition of a field programmable array which is configured by the central processing unit, the system is very flexible in terms of which image sensor is used and what type and level of image processing is accomplished in hardware. The ease of use of the system is improved by a library of intellectual property cores that enable the gate array to be interfaced to other processing cores. Pipelining of the pixel data stream allows insertion of several image processing operations as frames are captured. The system is compact and can easily be integrated into the camera housing without having to introduce forced cooling of the camera.
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Jul 2023
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I18-Microfocus Spectroscopy
Detectors
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Abstract: This Thesis describes the development and experimental testing of a new type of single-crystal chemical vapour deposition (CVD) diamond diagnostic instrument for synchrotron X-ray radiation. This pixelated detector is capable of non-destructively imaging the X-ray beam, and can remain in the beam path for the duration of synchrotron experiments. The detector can measure the position, profile, and flux of an incident beam. It has applications in beam position and profile monitoring, enabling active beam feedback and stabilisation.
The instrument utilises a single-crystal CVD diamond plate as the detector material, with laser-written conductive graphitic tracks embedded within the bulk diamond used as electrodes. The resulting instrument is an all-carbon X-ray imaging detector. Within the instrument’s transmissive aperture there is no surface metal- lization that could absorb X-rays, and no surface structures that could be damaged by exposure to synchrotron X-ray beams. The all-carbon design ensures that there is no danger of electrode materials introducing new absorption edges that may affect synchrotron experiments.
A novel modulation lock-in readout scheme enables each pixel of the detec- tor to be read out simultaneously. X-rays passing through the detector generate charge carriers within the bulk diamond through photoionisation, and these charge carriers travel to the nearest readout electrode under the influence of the modulated electrical bias. The signals from individual pixels are acquired by applying different modulation frequencies to different ‘bias’ electrodes, and measuring the resulting signal amplitude of those frequencies on perpendicular ‘readout’ electrodes. The system is designed to provide 100 frames per second image acquisition.
This instrument overcomes many of the issues associated with current gen- eration synchrotron diagnostic instruments, enabling real-time and non-destructive X-ray beam profile measurements to be obtained.
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Jun 2023
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Detectors
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J.
Correa
,
M.
Mehrjoo
,
R.
Battistelli
,
F.
Lehmkühler
,
A.
Marras
,
C. B.
Wunderer
,
T.
Hirono
,
V.
Felk
,
F.
Krivan
,
S.
Lange
,
I.
Shevyakov
,
V.
Vardanyan
,
M.
Zimmer
,
M.
Hoesch
,
K.
Bagschik
,
N.
Guerrini
,
B.
Marsh
,
I.
Sedgwick
,
G.
Cautero
,
L.
Stebel
,
D.
Giuressi
,
R. H.
Menk
,
A.
Greer
,
T.
Nicholls
,
W.
Nichols
,
U.
Pedersen
,
P.
Shikhaliev
,
N.
Tartoni
,
H. J.
Hyun
,
S. H.
Kim
,
S. Y.
Park
,
K. S.
Kim
,
F.
Orsini
,
F. J.
Iguaz
,
F.
Büttner
,
B.
Pfau
,
E.
Plönjes
,
K.
Kharitonov
,
M.
Ruiz-Lopez
,
R.
Pan
,
S.
Gang
,
B.
Keitel
,
H.
Graafsma
Open Access
Abstract: The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science.
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Jan 2023
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Detectors
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L.
Manzanillas
,
S.
Aplin
,
A.
Balerna
,
P.
Bell
,
J.
Casas
,
M.
Cascella
,
S.
Chatterji
,
C.
Cohen
,
G.
Dennis
,
P.
Fajardo
,
H.
Graafsma
,
H.
Hirsemann
,
F. J.
Iguaz
,
K.
Klementiev
,
T.
Kołodziej
,
T.
Martin
,
R.
Menk
,
F.
Orsini
,
M.
Porro
,
M.
Quispe
,
B.
Schmitt
,
N.
Tartoni
,
M.
Turcato
,
C.
Ward
,
E.
Welter
Abstract: In past years efforts have concentrated on the development of arrays of Silicon Drift Detectors for X-ray spectroscopy. This is in stark contrast to the little effort that has been devoted to the improvement of germanium detectors, in particular for synchrotron applications. Germanium detectors have better energy resolution and are more efficient in detecting high energy photons than silicon detectors. In this context, the detector consortium of the European project LEAPS-INNOV has set an ambitious R&D program devoted to the development of a new generation of multi-element monolithic germanium detectors for X-ray detection. In order to improve the performance of the detector under development, simulations of the different detector design options have been performed. In this contribution, the efforts in terms of R&D are outlined with a focus on the modelization of the detector geometry and first performance results. These performance results show that a signal-to-background ratio larger than 1000 can be achieved in the energy range of interest from 5 keV to 100 keV.
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Dec 2022
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