Related papers: Concept of a Double Tilted Rowland Spectrograph fo…
Tunable Diode Laser Absorption Spectroscopy (TDLAS) tomography has been widely used for in situ combustion diagnostics, yielding images of both species concentration and temperature. The temperature image is generally obtained from the…
The R~300-1000 grating spectra from XMM-Newton and Chandra are a radical advance, allowing spectroscopic physics techniques to be applied to X-ray astronomy, revolutionizing a wide range of research. Ten years on these spectra will be…
To enable non-line-of-sight (NLoS) sensing and communications, dual-function radar-communications (DFRC) systems have recently proposed employing reconfigurable intelligent surface (RIS) as a reflector in wireless media. However, in the…
This paper develops a theoretical framework for the design of Active Split-Ring Resonators (ASRRs). An ASRR is a Split-Ring Resonator (SRR) equipped with a tunable negative resistor, enabling both switchability and quality factor boosting…
AGN are known to have complex X-ray spectra that depend on both the properties of the accreting SMBH (e.g. mass, accretion rate) and the distribution of obscuring material in its vicinity ("torus"). Often however, simple and even unphysical…
Defocused speckle photography has long been used to measure rotations of rough surfaces. This paper explains how, by adding a suitably perforated mask, some measurement properties, such as range or lateral resolution, may be changed at…
Maximizing the grating efficiency is a key goal for the first light instrument IRIS (Infrared Imaging Spectrograph) currently being designed to sample the diffraction limit of the TMT (Thirty Meter Telescope). Volume Phase Holographic (VPH)…
IRIS is a near-infrared (0.84 to 2.4 microns) integral field spectrograph and wide-field imager being developed for first light with the Thirty Meter (TMT). It mounts to the advanced optics (AO) system NFIRAOS and has integrated…
3D Gaussian Splatting (3DGS) has recently revolutionized radiance field reconstruction, achieving high quality novel view synthesis and fast rendering speed without baking. However, 3DGS fails to accurately represent surfaces due to the…
Operation of an X-ray spectrometer based on a spherical variable line spacing grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and spectrometer geometry. The analysis is…
The soft X-ray band hosts a larger, more diverse range of variable sources than any other region of the electromagnetic spectrum. They are stars, compact binaries, SMBH's, the X-ray components of Gamma-Ray Bursts, their X-ray afterglows,…
Interferometry provides one of the possible routes to ultra-high angular resolution for X-ray and gamma-ray astronomy. Sub-micro-arc-second angular resolution, necessary to achieve objectives such as imaging the regions around the event…
Douglas-Rachford Splitting (DRS) methods based on the proximal point algorithms for the Poisson and Gaussian log-likelihood functions are proposed for ptychography and phase retrieval. Fixed point analysis shows that the DRS iterated…
We present new developments of the laser-induced transient grating spectroscopy (TGS) technique that enable the measurement of large area 2D maps of thermal diffusivity and surface acoustic wave speed. Additional capabilities include…
We developed a 2-mm-thick CdTe double-sided strip detector (CdTe-DSD) with a 250 um strip pitch, which has high spatial resolution with a uniform large imaging area of 10 cm$^2$ and high energy resolution with high detection efficiency in…
Achieving reliable and quantifiable performance in large-area surface-enhanced Raman spectroscopy (SERS) substrates has long been a formidable challenge. It requires substantial signal enhancement while maintaining a reproducible and…
X-ray reflection generates much of the spectral complexity in the X-ray spectra of AGN. It is argued that strong relativistic blurring of the reflection spectrum should commonly be expected from objects accreting at a high Eddington rate.…
Angle-resolved Raman spectroscopy (ARRS) is an effective method to analyze the symmetry of phonons and other excitations in molecules and solid-state crystals. While there are several configurations of ARRS instruments, the measurement…
Coherent x-ray diffractive imaging is extended to high resolution strain analysis in crystalline nanostructured devices. The application potential is demonstrated by determining the strain distribution in (Ga,Mn)As/GaAs nanowires. By…
We review the current state of efforts to use resonant soft x-ray scattering (RSXS), which is an elastic, momentum-resolved, valence band probe of strongly correlated electron systems, to study stripe-like phenomena in copper-oxide…