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Related papers: Momentum ray transforms

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Implicit Regularization (IReg) is a candidate to become an invariant framework in momentum space to perform Feynman diagram calculations to arbitrary loop order. In this work we present a systematic implementation of our method that…

High Energy Physics - Theory · Physics 2011-06-20 A. L. Cherchiglia , Marcos Sampaio , M. C. Nemes

Goos-Hanchen (GH) and Imbert-Fedorov (IF) shifts are lateral and transverse displacements of a wavepacket reflecting off a surface. A dramatic real-space manifestation of wavepacket phases, they have traditionally been analyzed in a model…

Mesoscale and Nanoscale Physics · Physics 2019-11-27 Li-kun Shi , Justin C. W. Song

Magnetic reconnection provides the primary source for explosive energy release, plasma heating and particle acceleration in many astrophysical environments. The last years witnessed a revival of interest in the MHD tearing instability as a…

Plasma Physics · Physics 2019-11-13 Emanuele Papini , Simone Landi , Luca Del Zanna

Recovering a function from integrals over conical surfaces recently got significant interest. It is relevant for emission tomography with Compton cameras and other imaging applications. In this paper, we consider the weighted conical Radon…

Numerical Analysis · Mathematics 2018-12-05 Markus Haltmeier , Daniela Schiefeneder

We introduce a technique for recovering a sufficiently smooth function from its ray transform over a wide class of curves in a general region of Euclidean space. The method is based on a complexification of the underlying vector fields…

Complex Variables · Mathematics 2010-11-12 Nicholas Hoell , Guillaume Bal

The hypothesis that the Lorentz transformations may be modified at Planck scale energies is further explored. We present a general formalism for theories which preserve the relativity of inertial frames with a non-linear action of the…

General Relativity and Quantum Cosmology · Physics 2011-05-05 Joao Magueijo , Lee Smolin

Let $\bbK=\mathbb R, \mathbb C, \mathbb H$ be the field of real, complex or quaternionic numbers and $M_{p, q}(\bbK)$ the vector space of all $p\times q$-matrices. Let $X$ be the matrix unit ball in $M_{n-r, r}(\bbK)$ consisting of…

Functional Analysis · Mathematics 2007-11-12 Genkai Zhang

We present observations of a new group of structures in the diffuse Galactic ISM: slender, linear HI features we dub "fibers" that extend for many degrees at high Galactic latitude. To characterize and measure the extent and strength of…

Astrophysics of Galaxies · Physics 2014-06-19 S E Clark , J E G Peek , M E Putman

Several novel imaging applications have lead recently to a variety of Radon type transforms, where integration is done over a family of conical surfaces. We call them \emph{cone transforms} (in 2D they are also called \emph{V-line} or…

Functional Analysis · Mathematics 2015-09-24 Fatma Terzioglu

Energetic particle transport in a finite amplitude magnetosonic and Alfvenic turbulence is considered using Monte Carlo particle simulations, which involve an integration of particle equation of motion. We show that in a low-Betha plasma…

Astrophysics · Physics 2008-02-03 G. Michalek , M. Ostrowski , R. Schlickeiser

In this paper, we investigate the recovery of the absorption coefficient from boundary data assuming that the region of interest is illuminated at an initial time. We consider a sufficiently strong and isotropic, but otherwise unknown…

Analysis of PDEs · Mathematics 2015-03-30 Sebastian Acosta

In this article, we study the problem of recovering symmetric $m$-tensor fields (including vector fields) supported in a unit disk $\mathbb{D}$ from a set of generalized V-line transforms, namely longitudinal, transverse, and mixed V-line…

Numerical Analysis · Mathematics 2024-11-08 Rohit Kumar Mishra , Anamika Purohit , Indrani Zamindar

Methods from soft-collinear effective theory are used to perform the threshold resummation of Sudakov logarithms for the deep-inelastic structure function F_2(x,Q^2) in the endpoint region x->1 directly in momentum space. An explicit…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Becher , Matthias Neubert

This report examines the thickness dependence of the reorientation phase transition in ferromagnetic films with perpendicular anisotropy. That is, we find the exact boundary of metastability of uniformly magnetized in-plane states as the…

Materials Science · Physics 2007-05-23 David Clarke

Although the \emph{residual method}, or \emph{constrained regularization}, is frequently used in applications, a detailed study of its properties is still missing. This sharply contrasts the progress of the theory of Tikhonov…

Optimization and Control · Mathematics 2012-12-06 Markus Grasmair , Markus Haltmeier , Otmar Scherzer

If $f(x,k)$ is the Jost solution and $f(x) = f(0,k)$, then the $I$-function is $I(k) := \frac{f^\prime(0,k)}{f(k)}$. It is proved that $I(k)$ is in one-to-one correspondence with the scattering triple ${\mathcal S} :=\{S(k), k_j, s_j, \quad…

Mathematical Physics · Physics 2007-05-23 A. G. Ramm

We first give a constructive answer to the attenuated tensor tomography problem on simple surfaces. We then use this result to propose two approaches to produce vector-valued integral transforms which are fully injective over tensor fields.…

Differential Geometry · Mathematics 2018-11-30 Venkateswaran P. Krishnan , Rohit Kumar Mishra , François Monard

We explain the main concepts centered around Sharafutdinov's ray transform, its kernel, and the extent to which it can be inverted. It is shown how the ray transform emerges naturally in any attempt to reconstruct optical and stress tensors…

Optics · Physics 2007-05-23 H. Hammer , B. Lionheart

High-redshift 21-cm observations will provide crucial insights into the physical processes of the Epoch of Reionization. Next-generation interferometers such as the Square Kilometer Array will have enough sensitivity to directly image the…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Simon Gazagnes , Léon V. E. Koopmans , Michael H. F. Wilkinson

In this paper we consider the problem of recovering the conformal factor in a conformal class of Riemannian metrics from the boundary measurement of one wave field. More precisely, using boundary control operators, we derive an explicit…

Analysis of PDEs · Mathematics 2015-03-30 Sebastian Acosta