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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Detectors
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F.
Orsini
,
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
,
L.
Manzanillas
,
T.
Martin
,
R.
Menk
,
M.
Porro
,
M.
Quispe
,
B.
Schmitt
,
N.
Tartoni
,
M.
Turcato
,
C.
Ward
,
E.
Welter
Abstract: The high brilliance and coherent beams resulting from recent upgraded synchrotron radiation facilities open the way for a large range of experiments, where detectors play a key role in the techniques and methods developed to fully exploit the upgraded synchrotron. For instance, one of the major limitations of XAFS experiment is the performance of the detectors. In order to be able to measure more challenging samples and to cope with the very high photon flux of the current and future (diffraction limited) sources, technological developments of detectors are necessary. In this framework, the germanium detector developed in the European project LEAPS-INNOV aims at improving several technological aspects. This type of detector represents a very important class of instruments for X-ray spectroscopy due to the fact that they enable to detect efficiently photons of considerable higher energy with respect to silicon detectors. The objective of this project consists in pushing the detector performance beyond the state-of-the-art. Preliminary layout and main choices for the design studies of this new detector are presented in this paper.
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Oct 2022
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B16-Test Beamline
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R. M.
Wheater
,
L.
Jowitt
,
S.
Richards
,
M. C.
Veale
,
M. D.
Wilson
,
O. J. L.
Fox
,
K. J. S.
Sawhney
,
A. D.
Lozinskaya
,
A.
Shemeryankina
,
O. P.
Tolbanov
,
A.
Tyazhev
,
A. N.
Zarubin
Diamond Proposal Number(s):
[23500]
Abstract: A newly supplied 80 × 80 chromium compensated GaAs sensor with a matrix of 80 × 80 pixels on a 250
m pixel pitch has been characterised utilising microbeam mapping techniques at the Diamond Light Source. The GaAs:Cr sensor was mounted to a HEXITEC DAQ system before raster scanning an x-ray beam with area 25 × 25
m
in steps of 25
m, providing sub-pixel resolution spectroscopic imaging. Scans were performed with incident x-ray energies ranging from 12 to 45 keV. Following processing of the data in MatLab 2019b an analysis of defects previously observed in etched GaAs wafers occured. Findings indicate the presence of regions with reduced charge collection efficiency where up to 88 % of incident events show significant charge loss, and changing charge carrier lifetimes across the sensor.
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Mar 2021
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B16-Test Beamline
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M.
Borri
,
C.
Cohen
,
O.
Fox
,
J.
Groves
,
W.
Helsby
,
O.
Mathon
,
L.
Mcnicholl
,
S.
Pascarelli
,
K.
Sawhney
,
R.
Torchio
,
M.
Zuvic
Diamond Proposal Number(s):
[24637]
Open Access
Abstract: Germanium micro-strip sensors were selected as the sensor technology to take data in energy dispersive X-ray spectroscopy experiments at the Extremely Brilliant Source (EBS) in Grenoble (FR). It is important for this experimental technique to use sensors with a large uniform area and a fine pitch. The former determines the range of energy detectable with a single sensor. The latter improves spectral resolution. A high stopping power is also important to perform studies with hard X-rays.
The device under test in this measurement was a germanium micro-strip sensor made of 1024 strips with
pitch. The bulk was 1.5 mm thick. The sensor was assembled into a prototype cryostat part of the XH detector system. The device was tested at the B16 beamline at the Diamond Light Source (DLS) in Didcot (UK). The objective of the test-beam was to characterise charge-sharing between strips. In fact, this effect limits the spectral resolution of the device.
To carry out this test, the sensor was scanned over a subset of strips with micro-focused X-rays under different settings. These were beam energy and intensity, sensor temperature and bias voltage. Results are presented in this paper. It was measured that the full width half maximum of the charge-sharing profile across different strips was
for settings which were indicative of the experimental conditions at the EBS. This was a signal current per unit area on the sensor of
10−8 A/
, a bias voltage of -180 V and a temperature of -159
C.
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Dec 2020
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B16-Test Beamline
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S.
Santpur
,
A. J.
Blue
,
C.
Buttar
,
V.
Fadeyev
,
B.
Gallop
,
C.
Helling
,
C.
Labitan
,
P. W.
Phillips
,
L.
Poley
,
C.
Sawyer
,
M.
Ullán
,
Y.
Unno
Diamond Proposal Number(s):
[18807, 22002]
Abstract: Silicon strip sensors for the ATLAS Inner Tracker (ITk) have been designed to provide reliable particle detection in the high-radiation environment of the High-Luminosity Large Hadron Collider. One important design criterion for their development is the minimization of inactive sensor areas, which affect the hermiticity of particle detection inside the detector. In previous measurements of ATLAS silicon strip sensors, the charge-collecting area of individual strip implants has been mapped and found to agree with the sensor strip pitch and strip length. For strip implants next to the sensor bias ring, the extent of their charge-collecting area towards the inactive sensor area was previously unknown, which limited the accuracy of both overall detector hermiticity estimates and the position resolution for particle detection at the sensor edge. Therefore, measurements were conducted to map the area of charge collection for sensor strips at the edge of the active sensor area using a micro-focused X-ray beam. This publication presents measurements showing the extent of charge collection in the edge strips of silicon strip sensors for two generations of ATLAS ITk strip sensor modules. The measurements confirmed that charge deposited in a strip implant that is neither connected nor grounded leads to capacitive coupling to the adjacent strip, where it is indistinguishable from a hit in that strip.
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Sep 2020
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B16-Test Beamline
|
L.
Poley
,
A. J.
Blue
,
C.
Buttar
,
V.
Cindro
,
C.
Darroch
,
V.
Fadeyev
,
J.
Fernandez-Tejero
,
C.
Fleta
,
C.
Helling
,
C.
Labitan
,
I.
Mandić
,
S. Ne.
Santpur
,
D.
Sperlich
,
M.
Ullán
,
Y.
Unno
Diamond Proposal Number(s):
[18807, 22002]
Abstract: A significant aspect of the Phase-II Upgrade of the ATLAS detector is the replacement of the current Inner Detector with the ATLAS Inner Tracker (ITk). The ATLAS ITk is an all-silicon detector consisting of a pixel tracker and a strip tracker. Sensors for the ITk strip tracker have been developed to withstand the high radiation environment in the ATLAS detector after the High Luminosity Upgrade of the Large Hadron Collider at CERN, which will significantly increase the rate of particle collisions and resulting particle tracks. During their operation in the ATLAS detector, sensors for the ITk strip tracker are expected to accumulate fluences up to 1.6
1015neq/cm2 (including a safety factor of 1.5), which will significantly affect their performance. One characteristic of interest for highly irradiated sensors is the shape and homogeneity of the electric field inside its active area. For the results presented here, diodes with edge structures similar to full size ATLAS sensors were irradiated up to fluences comparable to those in the ATLAS ITk strip tracker and their electric fields mapped using a micro-focused X-ray beam (beam diameter 2
3
m2). This study shows the extension and shape of the electric field inside highly irradiated diodes over a range of applied bias voltages. Additionally, measurements of the outline of the depleted sensor areas allow a comparison of the measured leakage current for different fluences with expectations for the corresponding active areas.
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Aug 2020
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B16-Test Beamline
Detectors
|
K.
Metodiev
,
M.
Mironova
,
D.
Bortoletto
,
R.
Plackett
,
P.
Allport
,
I.
Asensi Tortajada
,
R.
Cardella
,
F.
Dachs
,
V.
Dao
,
M.
Dyndal
,
L.
Flores Sanz De Acedo
,
P.
Freeman
,
A.
Gabrielli
,
L.
Gonella
,
M.
Munker
,
H.
Pernegger
,
F.
Piro
,
P.
Riedler
,
A.
Sharma
,
E. J.
Schioppa
,
I.
Shipsey
,
W.
Snoeys
,
C.
Solans Sanchez
,
H.
Wennloef
,
D. P.
Weatherill
,
D.
Wood
,
S.
Worm
Diamond Proposal Number(s):
[2206]
Abstract: Detector prototypes are commonly characterised in testbeams, either using charged particles or X-rays. Charged particles are used to quantify detector performance in terms of absolute efficiency, while X-rays can provide additional information about the detector structure. This paper presents an alternative approach to calculating charged particle efficiencies, using the results of an X-ray testbeam of the mini-MALTA CMOS prototype at Diamond Light Source, and additional laboratory measurements. Results are presented for an unirradiated and an irradiated sample and compared to the results of charged particle testbeams at SPS and ELSA. The extrapolated efficiencies are in agreement with the measured values. Additionally, the extrapolated efficiency maps provide more insight about the location of the pixel inefficiencies, due to the better spatial resolution of the X-ray testbeam.
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Aug 2020
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J.-N.
Gruse
,
M. J. V.
Streeter
,
C.
Thornton
,
C.d.
Armstrong
,
C. D.
Baird
,
N.
Bourgeois
,
S.
Cipiccia
,
O. J.
Finlay
,
C. D.
Gregory
,
Y.
Katzir
,
N.c.
Lopes
,
S. P. D.
Mangles
,
Z.
Najmudin
,
D.
Neely
,
L. R.
Pickard
,
K. D.
Potter
,
P. P.
Rajeev
,
D. R.
Rusby
,
C. I. D.
Underwood
,
J.m.
Warnett
,
M.a.
Williams
,
J. C.
Wood
,
C. D.
Murphy
,
C. M.
Brenner
,
D. R.
Symes
Open Access
Abstract: X-rays generated by betatron oscillations of electrons in a laser-driven plasma accelerator were characterised and applied to imaging industrial samples. With a 125 TW laser, a low divergence beam with 7.5
2.6
108 photons mrad−2 per pulse was produced with a synchrotron spectrum with a critical energy of 14.6
1.3 keV. Radiographs were obtained of a metrology test sample, battery electrodes, and a damage site in a composite material. These results demonstrate the suitability of the source for non-destructive evaluation applications. The potential for industrial implementation of plasma accelerators is discussed.
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Jul 2020
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Abstract: We present experimental results and FLUKA Monte-Carlo simulations reproducing the counting efficiency and the energy resolution of the cerium-activated yttrium-aluminium-perovskite photon detectors installed on the VESUVIO neutron spectrometer at the ISIS Pulsed Neutron and Muon Source. In particular, we investigate the performance of these detectors in the energy range between 100 keV and 300 keV. In this range, the
-emission of the 197Au resonant analyser foils, installed on VESUVIO to select the energy of scattered neutrons, is predominant. Such photons are currently discarded by the low-level discrimination threshold of the acquisition electronics set to 600 keV. Here, we model the detector crystals for a series of thickness values, and we discuss how 2-cm-thick crystals would significantly reduce the acquisition times with respect to the 6-mm-thick crystals employed at present. Additionally, we show how the signal-to-background ratio can be substantially enhanced by shielding the scintillators with 0.5-mm-thick Pb foils. We finally discuss the improved detection performance on a model sample of interest for Cultural-Heritage applications.
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Apr 2020
|
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B16-Test Beamline
|
M.
Mironova
,
K.
Metodiev
,
P.
Allport
,
I.
Berdalovic
,
Daniela
Bortoletto
,
C.
Buttar
,
R.
Cardella
,
V.
Dao
,
M.
Dyndal
,
P.
Freeman
,
L.
Flores Sanz De Acedo
,
L.
Gonella
,
T.
Kugathasan
,
H.
Pernegger
,
F.
Piro
,
R.
Plackett
,
P.
Riedler
,
A.
Sharma
,
E. J.
Schioppa
,
I.
Shipsey
,
C.
Solans Sanchez
,
W.
Snoeys
,
H.
Wennlöf
,
D.
Weatherill
,
D.
Wood
,
S.
Worm
Diamond Proposal Number(s):
[2206]
Abstract: This paper outlines the results of investigations into the effects of radiation damage in the mini-MALTA depleted monolithic pixel sensor prototype. Measurements were carried out at Diamond Light Source using a micro-focus X-ray beam, which scanned across the surface of the device in 2
μm
steps. This allowed the in-pixel photon response to be measured directly with high statistics. Three pixel design variations were considered: one with the standard continuous
n−
layer layout and front-end, and extra deep p-well and
n−
gap designs with a modified front-end. Five chips were measured: one unirradiated, one neutron irradiated, and three proton irradiated. The standard design showed a decrease of 12% in pixel response after irradiation to 1e15
neq∕cm2
. For the two new designs the pixel response did not decrease significantly after irradiation. A decrease of pixel response at high biasing voltages was observed. The charge sharing in the chip was quantified and found to be in agreement with expectations.
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Mar 2020
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