B22-Multimode InfraRed imaging And Microspectroscopy
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Diamond Proposal Number(s):
[37069]
Open Access
Abstract: Cosmic infrared emission and absorption spectra often carry a well-defined and invariant 6.2 micron band that has been proposed to emanate from very small dust grains that may carry polyaromatic hydrocarbons. Hemoglycin, a well-defined polymer of glycine that also contains iron, has been found in meteorites of the primordial CV3 class and therefore originated in the solar protoplanetary disc. Here we suggest that the polymer hemoglycin should also be considered as a source of the cosmic 6.2micron emission and absorption. In quantum calculations, the principal amide I infrared absorption band of hemoglycin is centered, before splitting, at 6.0 microns. Multiple hemoglycin polymers interact to split amide I into the strong (a-) band in the region of 6.2 microns and the much weaker (a+) band in the region of 5.8 microns. Experimentally, these two components are seen in extracts of the Sutter's Mill meteorite and in stromatolite ooid. The two 11-mer glycine anti-parallel chains of hemoglycin have an exact structural analog in antiparallel poly-L-lysine beta sheet crystals which in the laboratory have an (a-) absorption peak at 6.21 microns. This wavelength coincidence, the demonstrated propensity of hemoglycin 4.9nm rods to form accreting lattice structures, and its proven existence in the solar protoplanetary disc suggest that the cosmic 6.2 micron emission and absorption could be from small grains that are hemoglycin lattices or shell-like vesicles carrying internal organic molecules of various types. Calculated hemoglycin ultraviolet absorptions associated with iron in the molecule match the observed ultraviolet extinction feature at nominal 2175 Angstroms.
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Mar 2024
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I24-Microfocus Macromolecular Crystallography
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Diamond Proposal Number(s):
[31420]
Open Access
Abstract: Hemoglycin, a 1494 Da polymer composed of iron and glycine has been detected in several carbonaceous meteorites. Iron atoms close out the ends of a 5nm anti-parallel glycine beta sheet and contribute visible and near infrared absorptions that are not present with glycine alone. The 483nm absorption of hemoglycin was discovered in theory and then observed on beamline I24 at Diamond Light Source. Light absorption in a molecule involves a coupled lower set of states receiving light energy that causes a transition into an upper set of states. In the reverse process some energy source, such as an X-ray beam, populates the upper set of molecular states, which then radiates light as it returns to the lower "ground" set of states. We report on visible light re-emission during X-ray irradiation of a hemoglycin crystal. The emission is dominated by bands centered at 489nm and 551nm.
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Feb 2023
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I14-Hard X-ray Nanoprobe
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Takaaki
Noguchi
,
Toru
Matsumoto
,
Akira
Miyake
,
Yohei
Igami
,
Mitsutaka
Haruta
,
Hikaru
Saito
,
Satoshi
Hata
,
Yusuke
Seto
,
Masaaki
Miyahara
,
Naotaka
Tomioka
,
Hope A.
Ishii
,
John P.
Bradley
,
Kenta K.
Ohtaki
,
Elena
Dobrică
,
Hugues
Leroux
,
Corentin
Le Guillou
,
Damien
Jacob
,
Francisco
De La Peña
,
Sylvain
Laforet
,
Maya
Marinova
,
Falko
Langenhorst
,
Dennis
Harries
,
Pierre
Beck
,
Thi H. V.
Phan
,
Rolando
Rebois
,
Neyda M.
Abreu
,
Jennifer
Gray
,
Thomas
Zega
,
Pierre-M.
Zanetta
,
Michelle S.
Thompson
,
Rhonda
Stroud
,
Kate
Burgess
,
Brittany A.
Cymes
,
John C.
Bridges
,
Leon
Hicks
,
Martin R.
Lee
,
Luke
Daly
,
Phil A.
Bland
,
Michael E.
Zolensky
,
David R.
Frank
,
James
Martinez
,
Akira
Tsuchiyama
,
Masahiro
Yasutake
,
Junya
Matsuno
,
Shota
Okumura
,
Itaru
Mitsukawa
,
Kentaro
Uesugi
,
Masayuki
Uesugi
,
Akihisa
Takeuchi
,
Mingqi
Sun
,
Satomi
Enju
,
Aki
Takigawa
,
Tatsuhiro
Michikami
,
Tomoki
Nakamura
,
Megumi
Matsumoto
,
Yusuke
Nakauchi
,
Masanao
Abe
,
Masahiko
Arakawa
,
Atsushi
Fujii
,
Masahiko
Hayakawa
,
Naru
Hirata
,
Naoyuki
Hirata
,
Rie
Honda
,
Chikatoshi
Honda
,
Satoshi
Hosoda
,
Yu-Ichi
Iijima
,
Hitoshi
Ikeda
,
Masateru
Ishiguro
,
Yoshiaki
Ishihara
,
Takahiro
Iwata
,
Kousuke
Kawahara
,
Shota
Kikuchi
,
Kohei
Kitazato
,
Koji
Matsumoto
,
Moe
Matsuoka
,
Yuya
Mimasu
,
Akira
Miura
,
Tomokatsu
Morota
,
Satoru
Nakazawa
,
Noriyuki
Namiki
,
Hirotomo
Noda
,
Rina
Noguchi
,
Naoko
Ogawa
,
Kazunori
Ogawa
,
Tatsuaki
Okada
,
Chisato
Okamoto
,
Go
Ono
,
Masanobu
Ozaki
,
Takanao
Saiki
,
Naoya
Sakatani
,
Hirotaka
Sawada
,
Hiroki
Senshu
,
Yuri
Shimaki
,
Kei
Shirai
,
Seiji
Sugita
,
Yuto
Takei
,
Hiroshi
Takeuchi
,
Satoshi
Tanaka
,
Eri
Tatsumi
,
Fuyuto
Terui
,
Ryudo
Tsukizaki
,
Koji
Wada
,
Manabu
Yamada
,
Tetsuya
Yamada
,
Yukio
Yamamoto
,
Hajime
Yano
,
Yasuhiro
Yokota
,
Keisuke
Yoshihara
,
Makoto
Yoshikawa
,
Kent
Yoshikawa
,
Ryohta
Fukai
,
Shizuho
Furuya
,
Kentaro
Hatakeda
,
Tasuku
Hayashi
,
Yuya
Hitomi
,
Kazuya
Kumagai
,
Akiko
Miyazaki
,
Aiko
Nakato
,
Masahiro
Nishimura
,
Hiromichi
Soejima
,
Ayako I.
Suzuki
,
Tomohiro
Usui
,
Toru
Yada
,
Daiki
Yamamoto
,
Kasumi
Yogata
,
Miwa
Yoshitake
,
Harold C.
Connolly
,
Dante S.
Lauretta
,
Hisayoshi
Yurimoto
,
Kazuhide
Nagashima
,
Noriyuki
Kawasaki
,
Naoya
Sakamoto
,
Ryuji
Okazaki
,
Hikaru
Yabuta
,
Hiroshi
Naraoka
,
Kanako
Sakamoto
,
Shogo
Tachibana
,
Sei-Ichiro
Watanabe
,
Yuichi
Tsuda
Open Access
Abstract: Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (–OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.
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Dec 2022
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I24-Microfocus Macromolecular Crystallography
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Diamond Proposal Number(s):
[31420]
Open Access
Abstract: A 1494 Dalton hemoglycin space polymer of Glycine18 Hydroxy-glycine4 Fe2O4 termed the “core unit” is part of a polymer of Glycine, Si, Fe and O that forms tubes, vesicles and a lattice structure. It has been isolated from four different CV3 meteorites and characterized by mass spectrometry, FIB/SIMS and X-ray analysis. In quantum calculations (HF and DF wB97X-D 6-31G) the polymer has an absorption at 480 nm that is dependent on rectus “R” (= dextro D) chirality in a hydroxy glycine residue whose C-terminus is bonded to an iron atom. The absorption originates in the Fe II state as a consequence of chiral symmetry breaking. In confirmation of theory, measurements at Diamond Light Source UK, on crystals of hemoglycin derived from Acfer-086 and Sutter’s Mill meteorites have shown a strong 483 ± 3 nm absorption that confirms the proposed location of hydroxy glycine residues within the polymer. A high 483 nm to 580 nm absorption ratio points to an “R” chirality excess in hemoglycin, suggesting that 480 nm photons could have provided the energy for its replication in the protoplanetary disc.
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Sep 2022
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I13-1-Coherence
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Abstract: In this work, a characterization and optimization of phase-sensitive X-ray imaging techniques with a focus
on the field of laboratory astrophysics is given. Here, the advent of hard X-ray free electron lasers offers
novel opportunities as single-pulse imaging with sub-picosecond temporal resolution becomes possible. The
use of phase-sensitive techniques is often mandatory as micro- and nanoscopic samples show little or no attenuation
contrast. In order to fully benefit from the short pulse lengths at X-ray free electron lasers, these
methods should be reconcilable with single-exposure acquisition schemes. This task is complicated by zeroes
in the respective transfer functions of the imaging systems. Therefore, direct inversions are typically not
possible and sophisticated algorithms are required for the image reconstruction. Overall, this thesis mainly
focuses upon the grating-based X-ray imaging technique, also known as Talbot interferometry. For comparison,
propagation-based phase contrast imaging will also be considered. The investigations are divided into
analytical considerations, numerical simulations, and experimental implementations of the respective imaging
techniques.
An analytical examination of the image formation within a Talbot interferometer is presented. This process
can become complicated, especially for applications in X-ray microscopes. Here, transverse shifts of the
interference pattern in general depend nonlinearly on the phase differences across the X-ray wave field. Existing
reconstruction methods on the basis of deconvolutions then rely on idealized conditions, thus limiting
the experimental applicability of the method. In addition, the achievable spatial resolution of Talbot interferometry
in single-exposure applications is typically limited to the demagnified fringe period of the interference
pattern.
In order to resolve the limitations regarding the applicability, three novel reconstruction methods for Talbot
interferometry are conceptualized and implemented: the design of a beam-splitting diffraction grating featuring
only two diffraction orders, a two-stage deconvolution approach, and a statistical image reconstruction
method based on an analytical forward model of the imaging process and a regularized maximum likelihood
approach. The three schemes are validated on the basis of simulated data. They all prove advantageous when
the premises for standard deconvolution-based reconstructions are not met. The statistical image reconstruction
technique seems most promising as it achieves the best reconstruction quality at low photon numbers and
also circumvents the abovementioned limitations regarding the spatial resolution.
Building up on the simulative studies, two experimental realizations of Talbot interferometry at synchrotron
light sources are presented. In the first experiment, the single-exposure phase imaging capabilities
of Talbot interferometry in conjunction with the statistical image reconstruction method are investigated and
characterized on the basis of simple test samples. The broadened experimental applicability is demonstrated
through the retrieval of Fresnel diffraction images in an X-ray projection microscope. While a comparative
implementation of propagation-based phase contrast imaging at the same instrument still yields a superior
spatial resolution, the mitigation of limitations due to the fringe period is also verified experimentally. In the
second experiment, single-exposure phase imaging with both the grating-based and the propagation-based
approach is employed in order to monitor the moistening process of wood on the level of single wood cells...
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Aug 2022
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I11-High Resolution Powder Diffraction
I22-Small angle scattering & Diffraction
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Diamond Proposal Number(s):
[15125]
Abstract: Cosmic dust is the key to the chemical evolution of stars, planets, and life itself, but its composition is not well understood, and we can't currently collect samples for analysis. A few examples have arrived on Earth as interplanetary dust particles and comet dust, in meteorites, but their complicated history means they may not be representative. Our primary methods of investigating the properties of cosmic dust, therefore, are astronomical observations and laboratory experiments on analogue materials. Cosmic dust broadly divides into soot-like carbon grains and the more abundant refractory silicate grains, both of which are ejected from dying stars. Observations tell us that both amorphous and crystalline silicates form in the dust around Red Giant stars in varying proportions, but that the interstellar medium (ISM) contains only amorphous silicates. In work recently published in Astronomy & Astrophysics, a team of Diamond researchers led by Dr Stephen Thompson demonstrated that microwave drying can be used to cheaply and easily produce amorphous Mg–Fe silicates. They then investigated their crystallisation by in situ thermal annealing and considered the results in the context of modelling dust grains in protoplanetary disks.
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Jan 2020
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Metrology
Optics
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Carolyn
Atkins
,
William
Brzozowski
,
Naomi
Dobson
,
Maria
Milanova
,
Stephen
Todd
,
David
Pearson
,
Cyril J.
Bourgenot
,
David
Brooks
,
Robert M.
Snell
,
Wenjuan
Sun
,
Peter
Cooper
,
Simon G.
Alcock
,
Ioana-Theodora
Nistea
Abstract: Additive manufacturing (AM; 3D printing) is a fabrication process that builds an object layer-upon-layer and promotes the use of structures that would not be possible via subtractive machining. Prototype AM metal mirrors are increasingly being studied in order to exploit the advantage of the broad AM design-space to develop intricate lightweight structures that are more optimised for function than traditional open-back mirror lightweighting. This paper describes a UK Space Agency funded project to design and manufacture a series of lightweighted AM mirrors to fit within a 3U CubeSat chassis. Six AM mirrors of identical design will be presented: two in aluminium (AlSi10Mg), two in nickel phosphorous (NiP) coated AlSi10Mg, and two in titanium (Ti64). For each material mirror pair, one is hand-polished and the other is diamond turned. Metrology data, surface form error and surface roughness, will be presented to compare and contrast the different materials and post-processing methods. To assess the presence of porosity, a frequent concern for AM materials, X-ray computed tomography measurements will be presented to highlight the location and density of pores within the mirror substrates; methods to mitigate the distribution of pores near the optical surface will be described. As a metric for success the AlSi10Mg + NiP and AlSi10Mg mirrors should be suitable for visible and infrared applications respectively.
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Sep 2019
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Metrology
Optics
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Carolyn
Atkins
,
William
Brzozowski
,
Naomi
Dobson
,
Maria
Milanova
,
Stephen
Todd
,
David
Pearson
,
Cyril J.
Bourgenot
,
David
Brooks
,
Robert M.
Snell
,
Wenjuan
Sun
,
Peter
Cooper
,
Simon G.
Alcock
,
Ioana
Nistea
Abstract: Design for additive manufacture (AM; 3D printing) is significantly different than design for subtractive machining. Although there are some limitations on the designs that can be printed, the increase in the AM design-space removes some of the existing challenges faced by the traditional lightweight mirror designs; for example, sandwich mirrors are just as easy to fabricate as open-back mirrors via AM, and they provide an improvement in structural rigidity. However, the ability to print a sandwich mirror as a single component does come with extra considerations; such as orientation upon the build plate and access to remove any temporary support material. This paper describes the iterations in optimisation applied to the lightweighting of a small, 84mm diameter by 20mm height, spherical concave mirror intended for CubeSat applications. The initial design, which was fabricated, is discussed in terms of the internal lightweighting design and the design constraints that were imposed by printing and post-processing. Iterations on the initial design are presented; these include the use of topology optimisation to minimise the total internal strain energy during mirror polishing and the use of lattices combined with thickness variation i.e. having a thicker lattice in strategic support locations. To assess the suitability of each design, finite element analysis is presented to quantify the print-through of the lightweighting upon the optical surface for a given mass reduction.
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Sep 2019
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I11-High Resolution Powder Diffraction
I22-Small angle scattering & Diffraction
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Diamond Proposal Number(s):
[15125]
Open Access
Abstract: Context. Laboratory analogues can provide physical constraints to the interpretation of astronomical observations of cosmic dust but clearly do not experience the same formation conditions. To distinguish between properties intrinsic to the material and properties imprinted by their means of formation requires extensive characterisation. Aims. Sol-gel methods can produce amorphous silicates with potentially high reproducibility, but often require long drying times (24+ hours) at elevated temperatures in air, controlled atmosphere, or vacuum. We investigate the possibility that microwave drying can be used to form amorphous silicate on a timescale of ∼10 minutes and characterise their structural and spectroscopic properties relative to silicates produced by other drying methods. Methods. Microwave-dried amorphous MgSiO3, Fe 0.1Mg0.9SiO3 and Mg2SiO4 are characterised using X-ray powder diffraction, total X-ray scattering, small angle X-ray scattering and mid-IR FTIR spectroscopy, and compared to samples produced from the same gels, but dried in-air and under vacuum. The development of crystalline structure in the microwave-dried silicates via thermal annealing up to 999 ◦C is also investigated using in situ X-ray powder diffraction. Results. At the inter-atomic level the silicate structures are largely independent of drying method, however largerscale structured domains, ranging from a ∼few×10 ˚A to∼100’s ˚A in size, are observed. These are ordered as mass fractals with discernible variation caused by the drying processes. The mid-IR 10 μm band profile is also found to be influenced by the drying process, likely due to the way removal of water and bonded OH influences the distribution of tetrahedral species. However, microwave drying also allows Fe to be easily incorporated into the silicate structure. In situ annealing shows that for amorphous MgSiO3 crystalline forsterite, enstatite and cristobalite are high temperature phases, while for Mg2SiO4 forsterite crystallises at lower temperatures followed by cristobalite at high temperature. For Fe0.1Mg0.9SiO3 the crystallisation temperature is significantly increased and only forsterite is observed. Crystalline SiO2 may be diagnostic of Mg-rich, Fe-poor grain mineralogies. The results are discussed in relation to the different thermal conditions required for dust to crystallise within protoplanetary disk lifetimes. Conclusions. Sol-gel microwave drying provides a fast and easy method of producing amorphous Mg- and Fe,Mg-silicates of both pyroxene and olivine compositions. Their structure and spectroscopic characteristics although similar to silicates produced using other drying methods, exhibit subtle variations which are particularly manifest spectroscopically in the mid-IR, and structurally over medium- and long-range length scales.
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Mar 2019
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I06-Nanoscience (XPEEM)
Optics
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Diamond Proposal Number(s):
[5028]
Abstract: X-ray reflection near 45° via multilayer mirrors can be used for astronomical polarization measurements. A Cr/C multilayer mirror (designed for X-ray polarimetry at 250 eV), with a period thickness of 3.86 nm and a bi-layer number of 100, was fabricated using direct current magnetron sputtering. Grazing incidence X-ray reflectometry at 8 keV and transmission electron microscopy were used to investigate the multilayer structure. Different models were introduced to fit the hard X-ray reflectivity curve, which indicates that the layer thickness of two materials slightly drifts from the bottom to the top of the stack. Both the chromium and carbon layers are amorphous with asymmetric interfaces, while the Cr-on-C interface is slightly wider. Based on the good quality of the multilayer structure, a high reflectivity of 21.8% for the s-polarized light was obtained at 250 eV at a grazing incidence angle of 40.7°. The fabricated Cr/C multilayer mirror exhibits high reflectivity and polarization levels in the energy region of 240 eV–260 eV.
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Jun 2015
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