Related papers: Optimization of compact Soller collimator
In this work the concept of a novel slow neutron collimator and the way to operate it are presented. The idea is based on the possibility to decouple the device field-of-view from its collimation power. A multi-channel geometry is proposed…
The use of the minus identity lenses with the angle-cut collimator can achieve high contrast image in high-energy proton radiography. This article presents the principle of choosing the angle-cut aperture of the collimator for the different…
Radio-selected samples of quasars with complete optical identifications offer an ideal dataset with which to investigate dust bias associated with intervening absorption systems. Here, we review our work on the Complete Optical and Radio…
The effect of capture of X-ray beam into narrow submicron capillary was investigated with account for diffraction and decay of coherency by roughness scattering in transitional boundary layer. In contrast to well-known Andronov-Leontovich…
The Large Observatory For X-ray Timing (LOFT) is one of the candidate missions selected by the European Space Agency for an initial assessment phase in the Cosmic Vision programme. It is proposed for the M3 launch slot and has broad…
We consider a dimer formed by two particles with an attractive contact interaction in one dimension, colliding with a hard wall. We compute the scattering phase shifts and the reflection coefficients for various collision energies and…
Based on a paper published in 2019 by the FCAL Collaboration, this talk is giving an update of the Collaboration's effort to design prototype of highly compact calorimeter to instrument the very forward region of a detector at future…
Using a blue detuned laser shaped in a Laguerre-Gaussian donut mode we highly collimate the output of a two dimensional magneto-optical trap. The resulting atomic beam has a 1 mm diameter, its divergence is reduced from 40 down to 3 mrad…
This paper presents the analysis and characterization of the surface scattering process for both specular and diffused components. The study is focused on the investigation of various building materials each having a different roughness, at…
We study oblique incident light absorption in opaque media with rough surfaces. An analytical approach with modified boundary conditions taking into account the surface roughness in metallic or dielectric films has been discussed. Our…
We present methods and results of the testing of an inexpensive home-made diffraction limited lens system, the design of which was proposed in a recent paper and which has since been used (with slight alterations) by several research…
We have studied the correlation among X-ray absorption, optical reddening and nuclear dust morphology in Seyfert 2 galaxies. Two main conclusions emerge: a) the Balmer decrement and the amount of X-ray absorption are anticorrelated on a…
By combining the data from surveys for HI 21-cm absorption at various impact parameters in near-by galaxies, we report an anti-correlation between the 21-cm absorption strength (velocity integrated optical depth) and the impact parameter.…
Astronomical imaging with micro-arcsecond ($\mu$as) angular resolution could enable breakthrough scientific discoveries. Previously-proposed $\mu$as X-ray imager designs have been interferometers with limited effective collecting area. Here…
A study has been performed to understand the effects of radiation damage on various plastic scintillator tiles considered for a possible upgrade of the hadron calorimeter of the CMS detector. Measurements were made with unirradiated tiles…
We consider the inverse problem of in-line holography, applied to minimally-destructive imaging of cold atom clouds. Absorption imaging near-resonance provides a simple, but destructive measurement of atom column density. Imaging off…
We are developing instrumentation for a telescope design capable of measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics. Multilayer-coated mirrors are key to this approach, being used as Bragg…
Recent observations of Broad Absorption Line (BAL) quasars demonstrated that the soft X-ray emission of these objects is extremely weak and convincing evidence for very strong absorption by a high column density (~ 10^23.5 cm^-2) was…
We present results of an extensive suite of numerical simulations that probe square-tiled microwave absorber performance as a function of material properties, frequency, geometry, and unit cell size. The work, which probes both specular…
We describe measurements of the X-ray reflectance in the range 2 to 10 keV of samples representative of coated silicon wafers that are proposed for the fabrication of the XEUS (X-ray Evolving Universe Spectrometer) mission. We compare the…