I20-Scanning-X-ray spectroscopy (XAS/XES)
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Diamond Proposal Number(s):
[39257]
Open Access
Abstract: We discover satellites in Zn at emission energies of 8670–8675 eV. The satellite is detected with a significance exceeding 51.6 per pixel, enabled by the exceptional signal-to-noise ratio of the new dataset and novel technique. We have created the eXtended-range high-energy-resolution fluorescence detection (XR-HERFD) technique and applied it to Zn (Z = 30) using a novel 14-crystal analyser spectrometer. For this current work, data collection developed the first DOSE-S collection macros for Discovery-Onset-Spectrometry-Evolution of new Satellite processes. The energy dependence of the discovered satellite is tracked from the onset of the process at approximately 10791.7 eV through its evolution to higher energies. The satellite exhibits a clear manifold structure, consistent with multiple shake-off processes. We develop and apply Principal Component Analysis (PCA) and independently isolate the manifold of the satellite and prove the incident-energy evolution. We also fit the evolution to theoretical quantum mechanical models of such processes to provide strong confirmation of the physical origin. These findings demonstrate XR-HERFD’s capability to resolve weak many-body features and suggest new opportunities for studying shake processes and the many-body reduction factor . By resolving these satellites in what many people believed was a nominally simple metal and revealing rich many-body behaviour, this work opens a pathway to a physically grounded understanding of many-body effects in X-ray spectroscopy.
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Jul 2026
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Open Access
Abstract: We report the technical design, implementation and operation of a newly developed X-ray emission spectrometer on the I20 beamline at Diamond Light Source. The spectrometer consists of 14 crystal analysers arranged in an up–down configuration, allowing for operation in one- or two-colour acquisition modes. Since beginning operations in 2023, the spectrometer has substantially enhanced the capability of the beamline to perform X-ray emission spectroscopy (XES) and has demonstrated high reliability with minimal operational issues during user experiments. The latter achievement is particularly significant given the complexity of the instrument, and the difficulty of maintaining the Rowland condition when scanning the energy. We show that the spectrometer can effectively measure spectra in two-colour mode and is capable of detecting weak valence-to-core emission features with a significantly improved signal-to-background ratio. We also present data taken using a newly developed quick-scanning XES acquisition mode, which enables data collection in seconds rather than minutes. This mode opens up possibilities for time-resolved studies and investigating radiation-sensitive materials.
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May 2026
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B18-Core EXAFS
I20-Scanning-X-ray spectroscopy (XAS/XES)
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Jarrod C.
Lewis
,
Joseph
Fihosy
,
Akhil
Gupta
,
James
Tufnail
,
Kirk
Adams
,
Matthew
Coulson
,
Petr
Zagura
,
William
Iliffe
,
Nianhua
Peng
,
Diego
Gianolio
,
Shusaku
Hayama
,
Rebecca J.
Nicholls
,
Sofia
Diaz-Moreno
,
Susannah C.
Speller
Diamond Proposal Number(s):
[33243]
Open Access
Abstract: Understanding how irradiation degrades superconductivity in REBCO coated conductor is a pressing field of research for the development of compact fusion devices. Here, defect formation in GdBa2Cu3O
coated conductor is studied using a high dose of 2 MeV He
ion irradiation. While laboratory based X-ray diffraction and magnetometry measurements show that the crystal structure becomes less well ordered with the loss of superconductivity in the material, transmission electron microscopy reveals a complex landscape of structural defects within the as-manufactured tape which complicate the identification and characterisation of irradiation induced structural changes. To resolve this, three sets of polarisation dependent extended X-ray absorption fine structure (EXAFS) spectroscopy experiments were carried out to map the local structure of the Gd, Ba, and Cu atomic sites within the material, providing three independent probes for studying irradiation defects within the structurally anisotropic REBCO unit cell. Here the Ba and Cu environments were the more sensitive to the irradiation treatment, with only small changes to the Gd local structure observed. Both the Ba and Cu local structures retained much of the pristine structure in the a/b-plane following irradiation, with greater shifts evident in the c-axis aligned measurements. In the irradiated Cu K edge EXAFS analysis, a shifted peak in the c-axis aligned measurements is observed that is not compatible with the REBCO local structure. This is attributed to an O site irradiation defect motif consistent with a Frenkel defect.
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Apr 2026
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Open Access
Abstract: Nucleophosmin (NPM1) is a nucleolar protein commonly mutated in ~30% of newly diagnosed acute myeloid leukemia (AML) cases. These mutations occur in the terminal exon of the NPM1 gene, affecting the C-terminal DNA-binding domain of the protein and causing its delocalization to the cytoplasm—a hallmark of NPM1-mutated AML. NPM1 shuttling to the nucleoplasm is tightly regulated by posttranslational modifications, such as phosphorylation of Ser254, Ser260, and Tyr271 of the DNA-binding domain. However, the structural mechanisms underlying this process remain unclear. In this work, we show that Ser-to-Asp (S254D–S260D) and Tyr-to-pCMF (para-carboxymethyl phenylalanine) (Y271pCMF) phosphomimetic mutations induce significant structural and dynamical rearrangements, as well as drastic modifications in electrostatic surface potential. These changes compromise recognition of a G-quadruplex sequence from the c-MYC promoter by reducing DNA-binding affinity, reshape histone capturing dynamics, and fade charge segregation in the histone-binding domain. Combination of such substitutions in a triple phosphomimetic variant (S254D–S260D–Y271pCMF) further destabilizes the domain’s structure and triggers protein aggregation. Altogether, these findings suggest that phosphorylation of Ser254, Ser260, and Tyr271 of the C-end DNA-binding domain weakens both DNA affinity and charge block-driven liquid–liquid phase separation, offering a molecular explanation for the delocalization of NPM1 outside of the nucleolus.
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Mar 2026
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I14-Hard X-ray Nanoprobe
I20-Scanning-X-ray spectroscopy (XAS/XES)
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Diamond Proposal Number(s):
[34837, 38234, 38452]
Open Access
Abstract: Metals play an essential role in cellular homeostasis and are key components of several formulations currently used in the clinic. Synchrotron-based X-ray microscopy at submicron resolution is a powerful approach to map intracellular elemental distributions and to monitor how these patterns change upon genetic or pharmacological perturbations. However, existing sample-preparation protocols often rely on costly and highly specialized equipment for vitrification and dehydration, limiting their widespread adoption. Here, we present an adapted plunge-freezing and freeze-drying workflow that enables the preparation of mammalian cell samples for X-ray fluorescence (XRF) and X-ray absorption spectroscopy (XAS) studies with submicron resolution in a cost-effective and versatile manner. Furthermore, we define acquisition parameters optimized for the reliable detection of low-abundance metals, such as endogenous iron. We anticipate that this accessible protocol will facilitate the broader implementation of synchrotron-based inner-shell spectromicroscopy in cell biology.
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Mar 2026
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Diamond Proposal Number(s):
[31940]
Abstract: Epitaxial YBa 2 Cu3O7−δ/MgO thin films fabricated with pulsed laser deposition are grown as idealised epitaxial systems with a minimal number of different elements for X-ray absorption spectroscopy studies of irradiation damage. These films are characterised in terms of their superconducting performance, crystallinity, surface morphology, and Cu local environment. This reveals a structural heterogeneity of [100] oriented material, referred to as “a-axis grains”, decorating the desired [001] oriented phase of the thin film, coinciding with suppressed superconducting performance.
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Jan 2026
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Open Access
Abstract: We report the first experimental discovery of Hidden Satellites within the Kemission lines of manganese metal (Mn, ) with a total integrated statistical significance exceeding 270 (standard error), far beyond the discovery threshold. Experimental data were collected at the I20-Scanning beamline at the Diamond Light Source using our new eXtended-Range High-Energy-Resolution Fluorescence Detection (XR-HERFD) technique. The Hidden Satellites, embedded in the core emission structure, represent novel quantum many-body processes that evolve systematically as the incident photon energy increases. Principal Component Analysis (PCA) was applied to extract the major separable physical processes and validate the significance of the observed Hidden Satellites. The application of physical insight to the PCA method allowed us to isolate the satellites, and measure the evolutionary profile. Our paper reveals that the total intensity of shake-off satellites can reach as high as 20–25%. Although these are hidden, they are very significant. These results directly challenge the traditional treatment of the many-body reduction factor, , as a constant in the standard XAFS equation. Our findings demonstrate that this term must be modelled as an energy-dependent function, reflecting its variation with incident photon energy and highlighting its role in many-body interactions. This deeper understanding of fundamental atomic processes directly impacts relativistic quantum mechanics, in theory and application. Also, this develops the two most popular experimental techniques at synchrotrons: X-ray absorption and X-ray emission spectroscopy, responsible for some 12,000 papers per annum, and all applications of these techniques in chemistry, physics, and biology. It offers insights into the evolution of satellites and underscores the broader implications of hidden features in X-ray spectra.
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Dec 2025
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Jack
Stephens
,
Ramesh
Rijal
,
Daniel
Sier
,
Nicholas T. T.
Tran
,
Jonathan W.
Dean
,
Paul
Di Pasquale
,
Tony
Kirk
,
Minh
Dao
,
Chanh Q.
Tran
,
Shusaku
Hayama
,
Sofia
Diaz-Moreno
,
Christopher T.
Chantler
Diamond Proposal Number(s):
[39257]
Open Access
Abstract: The discovery of the novel n = 2 satellite transition in the Kβ emission spectrum of manganese and its evolution with incident photon energy are presented. Using the XR-HERFD (extended-range high-energy-resolution fluorescence detection) technique, we conclusively demonstrate the existence of this phenomenon with a statistical significance corresponding to 652 σse across the measured spectrum, far above the discovery threshold of 3–6 σse. We apply principal component analysis (PCA) to the XR-HERFD data to extract advanced structural insights. The evolution of this novel spectral feature and physical process are quantified by incorporating regression, revealing the increase in intensity over a wide range of incident photon energies. We validate these findings through independent test data. These results directly challenge the conventional treatment of the many-body reduction factor S02 as a constant independent of incident photon energy in the standard XAFS (X-ray absorption fine structure) equation. Thereby, these results present compelling evidence that S02 should be modelled as a varying function of incident photon energy, marking the first observation of this behaviour in Kβ spectra. This facilitates a greater quantitative understanding of HERFD spectra and a comprehensive representation of many-body effects in condensed matter systems.
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Sep 2025
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Ramesh
Rijal
,
Jack
Stephens
,
Daniel
Sier
,
Nicholas T. T.
Tran
,
Truong V. B.
Nguyen
,
Jonathan W.
Dean
,
Pierce
Bowman
,
Minh
Dao
,
Paul
Di Pasquale
,
Tony
Kirk
,
Chanh Q.
Tran
,
Shusaku
Hayama
,
Matteo
Aramini
,
Nitya
Ramanan
,
Sofia
Diaz-Moreno
,
Christopher T.
Chantler
Open Access
Abstract: This study of manganese (Mn, Z = 25) introduces a novel combination of extended-range high energy resolution fluorescence detection (XR-HERFD), multiple-crystal spectrometers and advanced binary data splicing techniques to address challenges in X-ray emission spectroscopy. XR-HERFD enhances spectral precision by utilizing high-resolution crystal analysers and optimized detector configurations. The systematic application of these methods using multiple Bragg crystal analysers at Diamond Light Source has led to substantial improvements in data quality. Simultaneously, advanced binary data splicing integrates multiple datasets to correct distortions and improve resolution, resulting in sharper spectral features. Our results show a significant increase in peak counts and a notable reduction in full width at half-maximum (FWHM), with peak amplitudes increasing by 83% and resolution improving by 46%. These developments provide greater detail for X-ray absorption or emission spectra, offering valuable insights into complex materials, and permitting advances and breakthroughs in atomic relativistic quantum mechanics, chemical sensitivity of atomic transitions and modelling of solid-state effects.
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Jul 2025
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I20-Scanning-X-ray spectroscopy (XAS/XES)
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Diamond Proposal Number(s):
[19223]
Abstract: High-charge micas exhibit improved adsorption properties and are a promising alternative clay material for the engineered barrier in deep geological repositories. When combined with Eu3+ cations, they serve as an in situ luminescent probe for tracking the physical–chemical changes occurring in this engineered barrier over the long term. Therefore, a better understanding of the local environment of the lanthanide is highly desirable to comprehend the specific behavior of these systems. A combination of different techniques, (X-ray diffraction, thermogravimetry, fluorescence, and X-ray absorption spectroscopy), has allowed the study of the local environment of two luminescent lanthanide cations, Eu3+ and Gd3+, embedded in the galleries of two high-charge micas with different Si/Al tetrahedral ratio. The results show that the hydration state of these cations is primarily influenced by the layer charge of the aluminosilicate, and secondarily by the cation’s hydration enthalpy. High-charge micas doped with trivalent lanthanide cations are more hydrated compared to the original clays with Na+ in the interlayer. Nevertheless, both Eu3+ and Gd3+ are adsorbed as inner-sphere complexes in the galleries of high-charge micas. They are located inside the distorted hexagonal cavity in all cases, coordinated by 3 oxygens from the tetragonal sheet, one fluorine from the octahedral sheet, and by 2–4 oxygens from water molecules, all at distances around 2.4 Å. An additional oxygen atom at a distance of 3.45–3.50 Å, is proposed from an H2O molecule in the second coordination shell.
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Jan 2025
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