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We present a generalisation of surface photometry to the higher-order moments of the line-of-sight velocity distribution of galaxies observed with integral-field spectrographs. The generalisation follows the approach of surface photometry…

Astrophysics · Physics 2009-11-13 Davor Krajnovic , Michele Cappellari , P. Tim de Zeeuw , Yannick Copin

Random-scan Gibbs samplers possess a natural hierarchical structure. The structure connects Gibbs samplers targeting higher dimensional distributions to those targeting lower dimensional ones. This leads to a quasi-telescoping property of…

Probability · Mathematics 2022-10-17 Qian Qin , Guanyang Wang

This paper addresses the issue of inversion in cases where (1) the observation system is modeled by a linear transformation and additive noise, (2) the problem is ill-posed and regularization is introduced in a Bayesian framework by an a…

Machine Learning · Statistics 2026-02-12 Jean-François Giovannelli

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The…

General Relativity and Quantum Cosmology · Physics 2011-09-28 Thomas P. Kling , Louis Bianchini

We demonstrate spectroscopy of incoherent light with sub-diffraction resolution. In a proof-of-principle experiment we analyze the spectrum of a pair of incoherent point-like sources whose separation is below the diffraction limit. The two…

We present a new methodology to derive the positions of the Sgr B molecular clouds (MCs) along the line of sight, as an application study of the Galactic center diffuse X-rays (GCDX). The GCDX is composed of hot plasma emission of about 7…

Astrophysics of Galaxies · Physics 2015-05-13 Syukyo G. Ryu , Katsuji Koyama , Masayoshi Nobukawa , Ryosuke Fukuoka , Takeshi Go Tsuru

Determining the redshift distribution $n(z)$ of galaxy samples is essential for several cosmological probes including weak lensing. For imaging surveys, this is usually done using photometric redshifts estimated on an object-by-object…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-31 Jörg Herbel , Tomasz Kacprzak , Adam Amara , Alexandre Refregier , Claudio Bruderer , Andrina Nicola

We introduce a new type of lens that focuses a plane wave into a spherical one, where light comes from all directions. Our method also suggests the design of ideal optical tweezers or, in the reverse direction, photo-detection of nearly all…

Optics · Physics 2025-04-01 Shay Rabani , Kirill Shvalb , Boris Malomed , Tal Carmon

This paper presents an alternative formulation of the geodesic normal distribution on the sphere, building on the work of Hauberg (2018). While the isotropic version of this distribution is naturally defined on the sphere, the anisotropic…

Statistics Theory · Mathematics 2024-11-25 José E. Chacón , Andrea Meilán-Vila

Given a parametric polynomial curve $\gamma:[a,b]\rightarrow \mathbb{R}^n$, how can we sample a random point $\mathfrak{x}\in \mathrm{im}(\gamma)$ in such a way that it is distributed uniformly with respect to the arc-length? Unfortunately,…

Computational Geometry · Computer Science 2022-09-28 Apostolos Chalkis , Christina Katsamaki , Josué Tonelli-Cueto

The light distribution on the focal surface of spheric mirrors designed for telescopes in the lens-less Schmidt configuration is calculated analytically using geometrical optics. This analysis was motivated by considerations of the design…

Instrumentation and Methods for Astrophysics · Physics 2009-09-16 Paolo Walter Cattaneo

Gravitational lensing by a spiral galaxy occurs when the line-of-sight to a background quasar passes within a few kpc from the center of the galactic disk. Since galactic disks are rich in neutral hydrogen, the quasar spectrum will likely…

Astrophysics · Physics 2016-08-30 Abraham Loeb

We develop a non--perturbative method that yields analytical expressions for the deflection angle of light in a general static and spherically symmetric metric. It is an improvement on a method previously devised by the authors, and…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Paolo Amore , Mayra Cervantes , Arturo De Pace , Francisco M. Fernandez

Hubble Space Telescope images of high-redshift galaxies selected via color and photometric redshifts are used to examine the size and axial-ratio distribution of galaxies as a function of redshift at lookback times t > 8 Gyr. These…

Optical diffraction tomography is an indispensable tool for studying objects in three-dimensions due to its ability to accurately reconstruct scattering objects. Until now this technique has been limited to coherent light because spatial…

Astronomical X-ray observatories with grazing incidence optics face the problem of pseudo-focusing of low energy protons from the mirrors towards the focal plane. Those protons constitute a variable, unpredictable component of the non X-ray…

Instrumentation and Methods for Astrophysics · Physics 2020-04-15 R. Amato , T. Mineo , A. D'Aì , S. Diebold , V. Fioretti , A. Guzman , S. Lotti , C. Macculi , S. Molendi , E. Perinati , C. Tenzer , A. Santangelo

Light scattering in random media is usually considered within the framework of the three-dimensional Anderson universality class, with modifications for the vector nature of electromagnetic waves. We propose that the linear dispersiveness…

Disordered Systems and Neural Networks · Physics 2025-08-05 Tobias Micklitz , Alexander Altland

We consider the problem of scale detection in images where a region of interest is present together with a measurement tool (e.g. a ruler). For the segmentation part, we focus on the graph based method by Flenner and Bertozzi which…

Analysis of PDEs · Mathematics 2016-09-26 Luca Calatroni , Yves van Gennip , Carola-Bibiane Schönlieb , Hannah Rowland , Arjuna Flenner

The emission of electromagnetic waves from a source within or near a non-trivial medium (with or without boundaries, crystalline or amorphous, with inhomogeneities, absorption and so on) is sometimes studied using the reciprocity principle.…

Classical Physics · Physics 2016-09-08 Ariel Caticha

In this paper alternative method for real-time 3D model rasterization is given. Surfaces are drawn in perspective-map space which acts as a virtual camera lens. It can render single-pass 360{\deg} angle of view (AOV) image of unlimited…

Graphics · Computer Science 2020-10-20 Jakub Maksymilian Fober
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