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Related papers: Analysis of microroughness evolution in X-ray astr…

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To enhance the reflectivity of X-ray mirrors beyond the critical angle, multilayer coatings are required. Interface imperfections in the multilayer growth process are known to cause non-specular scattering and degrade the mirror optical…

Optics · Physics 2013-04-05 B. Salmaso , D. Spiga , R. Canestrari , L. Raimondi

The focusing performance of X-ray optics (conveniently expressed in terms of HEW, Half Energy Width) strongly depend on both mirrors deformations and photon scattering caused by the microroughness of reflecting surfaces. In particular, the…

Astrophysics · Physics 2007-11-28 Daniele Spiga

The imaging performance of X-ray optics (expressed in terms of HEW, Half-Energy-Width) can be severely affected by X-ray scattering caused by the surface roughness of the mirrors. The impact of X-ray scattering has an increasing relevance…

Astrophysics · Physics 2008-01-16 D. Spiga , G. Pareschi , R. Canestrari , V. Cotroneo

Future hard (10 -100 keV) X-ray telescopes (SIMBOL-X, Con-X, HEXIT-SAT, XEUS) will implement focusing optics with multilayer coatings: in view of the production of these optics we are exploring several deposition techniques for the…

Instrumentation and Methods for Astrophysics · Physics 2015-09-09 D. Spiga , A. Mirone , G. Pareschi , R. Canestrari , V. Cotroneo , C. Ferrari , C. Ferrero , L. Lazzarini , D. Vernani

Future X-ray telescopes like SIMBOL-X will operate in a wide band of the X-ray spectrum (from 0.1 to 80 keV); these telescopes will extend the optical performances of the existing soft X-ray telescopes to the hard X-ray band, and in…

Instrumentation and Methods for Astrophysics · Physics 2015-09-10 D. Spiga , G. Cusumano , G. Pareschi

One of the most important parameters defining the angular resolution of an X-ray optical module is its Half-Energy Width (HEW) as a function of the photon energy. Future X-ray telescopes with imaging capabilities (SIMBOL-X, Constellation-X,…

Instrumentation and Methods for Astrophysics · Physics 2015-09-10 D. Spiga

The imaging sharpness of an X-ray telescope is chiefly determined by the optical quality of its focusing optics, which in turn mostly depends on the shape accuracy and the surface finishing of the grazing-incidence X-ray mirrors that…

Instrumentation and Methods for Astrophysics · Physics 2014-12-10 Lorenzo Raimondi , Daniele Spiga

Multilayer X-ray mirrors consist of a coating of a large number of alternate layers of high Z and low Z materials with a typical thickness of 10-100 Angstrom, on a suitable substrate. Such coatings play an important role in enhancing the…

X-ray mirrors with high focusing performances are in use in both mirror modules for X-ray telescopes and in synchrotron and FEL (Free Electron Laser) beamlines. A degradation of the focus sharpness arises in general from geometrical…

Optics · Physics 2013-04-05 D. Spiga , L. Raimondi , C. Svetina , M. Zangrando

Incoherent surface scattering yields a statistical description of the surface, due to the ensemble averaging over many independently sampled volumes. Depending on the state of the surface and direction of the scattering vector relative to…

Statistical Mechanics · Physics 2009-11-11 Darren Dale , Aaron Fleet , Y. Suzuki , J. D. Brock

Uniform powder spreading is a requisite for creating consistent, high-quality components via powder bed additive manufacturing (AM), wherein layer density and uniformity are complex functions of powder characteristics, spreading kinematics,…

Sophisticated thin film growth techniques increasingly rely on the addition of a plasma component to open or widen a processing window, particularly at low temperatures. However, the addition of the plasma into the growth environment also…

The surface figure of x-ray mirrors can be improved by differential deposition of thin films. To achieve the required corrections, WSi2 layers of variable thickness were deposited through beam-defining apertures of different openings. The…

Optics · Physics 2025-06-03 Ch. Morawe , S. Labouré , F. Perrin , A. Vivo , R. Barrett

High resolution X-ray spectroscopy has revealed soft X-rays from high density plasma in Classical T-Tauri stars (CTTSs), probably arising from the accretion shock region. However, the mass accretion rates derived from the X-ray observations…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. L. Curran , C. Argiroffi , G. G. Sacco , S. Orlando , G. Peres , F. Reale , A. Maggio , .

To take advantage of high-resolution optics sensitive to a broad energy range, future X-ray imaging instruments will require thick detectors with small pixels. This pixel aspect ratio affects spectral response in the soft X-ray band, vital…

X-ray reflectometry (XRR) provides researchers and manufacturers with a non-destructive way to determine thickness, roughness, and density of thin films deposited on smooth substrates. Due to the nested nature of equations modeling this…

Materials Science · Physics 2015-06-12 Donald Windover , David L. Gil , Yasushi Azuma , Toshiyuki Fujimoto

Improving angular resolution is one of X-ray astronomy's big challenges. While X-ray interferometry should eventually vastly improve broad-band angular resolution, in the near-term, X-ray telescopes will sacrifice angular resolution for…

Astrophysics · Physics 2007-05-23 Craig J. Copi , Glenn D. Starkman

Many nano and quantum devices, with their sizes often spanning from millimeters down to sub-nanometer, have intricate low-dimensional, non-uniform, or hierarchical structures on surfaces and interfaces. Since their functionalities are…

Field-of-view and resolution trade-offs in X-Ray micro-computed tomography (micro-CT) imaging limit the characterization, analysis and model development of multi-scale porous systems. To this end, we developed an applied methodology…

XEUS, the X-ray Evolving Universe Spectroscopy mission, is at present an ESA-ISAS initiative for the study of the evolution of the hot Universe in the post-Chandra/XMM-Newton era. The key science objectives of XEUS are: Search for the…

Astrophysics · Physics 2016-08-30 Johan Bleeker , Mariano Mendez
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