English
Related papers

Related papers: Skylight: a new code for general-relativistic ray-…

200 papers

In order to study transient phenomena in the Universe, existing and forthcoming imaging surveys are covering wide areas of sky repeatedly over time, with a range of cadences, point spread functions, and depths. We describe here a framework…

Instrumentation and Methods for Astrophysics · Physics 2023-08-11 D. L. Shupe , F. J. Masci , R. Chary , G. Helou , A. L. Faisst , R. M. Cutri , T. Y. Brooke , J. A. Surace , K. A. Marsh

The reconstruction of a smooth field onto a fixed grid is a necessary step for direct comparisons to various real-world observations. Projecting SPH data onto a fixed grid becomes challenging in adaptive environments, where some particles…

Astrophysics of Galaxies · Physics 2021-06-14 Josh Borrow , Ashley J. Kelly

We describe a novel adaptive ray tracing scheme to solve the equation of radiative transfer around point sources in hydrodynamical simulations. The angular resolution adapts to the local hydrodynamical resolution and hence is of use for…

Astrophysics · Physics 2009-11-07 Tom Abel , Benjamin D. Wandelt

We present a new version of the fully 3D photoionization and dust radiative transfer code, MOCASSIN, that uses a Monte Carlo approach for the transfer of radiation. The X-ray enabled MOCASSIN allows a fully geometry independent description…

Astrophysics · Physics 2009-11-13 Barbara Ercolano , Peter R. Young , Jeremy J. Drake , John C. Raymond

At low redshift, it is possible to combine spectroscopic information of galaxies with their luminosity or angular diameter distance to directly measure the projection of peculiar velocities (PV) along the line-of-sight. A PV survey probing…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-02 Mattia Pantiri , Matteo Foglieni , Enea Di Dio , Emanuele Castorina

Measuring the brightness of the night sky has become an increasingly important topic in recent years, as artificial lights and their scattering by the Earths atmosphere continue spreading around the globe. Several instruments and techniques…

We introduce a transformer-based neural network to generate high-resolution (3km) synthetic radar reflectivity fields at scale from geostationary satellite imagery. This work aims to enhance short-term convective-scale forecasts of…

Signal Processing · Electrical Eng. & Systems 2024-07-02 Jason Stock , Kyle Hilburn , Imme Ebert-Uphoff , Charles Anderson

A key science goal of large sky surveys such as those conducted by the Vera C. Rubin Observatory and precursors to the Square Kilometre Array is the identification of variable and transient objects. One approach is the statistical analysis…

Ground-based astronomical spectra are contaminated by the Earth's atmosphere to varying degrees in all spectral regions. We present a Python code that can accurately fit a model to the telluric absorption spectrum present in astronomical…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Kevin Gullikson , Sarah Dodson-Robinson , Adam Kraus

Numerical relativity is an essential tool for solving Einstein's equations of general relativity for dynamical systems characterized by high velocities and strong gravitational fields. The implementation of new algorithms that can solve…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Stuart L. Shapiro

Gravitational waves from inspiraling compact binaries are known to be an excellent absolute distance indicator, yet it is unclear whether electromagnetic counterparts of these events are securely identified for measuring their redshifts,…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Masamune Oguri

Recent advances in implicit neural representations and differentiable rendering make it possible to simultaneously recover the geometry and materials of an object from multi-view RGB images captured under unknown static illumination.…

Computer Vision and Pattern Recognition · Computer Science 2022-04-15 Yuanqing Zhang , Jiaming Sun , Xingyi He , Huan Fu , Rongfei Jia , Xiaowei Zhou

We derive solutions to transit light curves of exoplanets orbiting rapidly-rotating stars. These stars exhibit significant oblateness and gravity darkening, a phenomenon where the poles of the star have a higher temperature and luminosity…

Earth and Planetary Astrophysics · Physics 2022-02-16 Shashank Dholakia , Rodrigo Luger , Shishir Dholakia

Numerical methods for radiative transfer play a key role in modern-day astrophysics and cosmology, including study of the inhomogeneous reionization process. In this context, ray tracing methods are well-regarded for accuracy but notorious…

Instrumentation and Methods for Astrophysics · Physics 2025-12-16 Nathan X. Marshak , Kathlynn Simotas , Zarija Lukić , Hyunbae Park , James Ahrens , Chris R. Johnson

We introduce a new 1D stellar spectral synthesis Python code called stardis. stardis is a modular, open-source radiative transfer code that is capable of spectral synthesis from near-UV to IR for FGK stars. We describe the structure,…

We address the problem of converting large-scale high-dimensional image data into binary codes so that approximate nearest-neighbor search over them can be efficiently performed. Different from most of the existing unsupervised approaches…

Computer Vision and Pattern Recognition · Computer Science 2015-12-02 Tsung-Yu Lin , Tsung-Wei Ke , Tyng-Luh Liu

Modern astrometry is based on angular measurements at the micro-arcsecond level. At this accuracy a fully general relativistic treatment of the data reduction is required. This paper concludes a series of articles dedicated to the problem…

In this paper we broadly consider techniques which utilize projections on rays for data collection, with particular emphasis on optical techniques. We formulate a variety of imaging techniques as either special cases or extensions of…

Computer Vision and Pattern Recognition · Computer Science 2014-02-12 Keith Dillon , Yeshaiahu Fainman

We present a novel method to search for structures of coherently aligned patterns in ultra-high energy cosmic-ray arrival directions simultaneously across the entire sky. This method can be used to obtain information on the Galactic…

Instrumentation and Methods for Astrophysics · Physics 2022-01-31 Marcus Wirtz , Teresa Bister , Martin Erdmann

The Galactic cosmic-ray propagation code GALPROP is designed to make predictions of many kinds of data self-consistently, including direct cosmic-ray measurements, gamma rays and synchrotron radiation. In the decade since its conception it…

High Energy Astrophysical Phenomena · Physics 2009-07-06 A. W. Strong , I. V. Moskalenko , T. A. Porter , G. Jóhannesson , E. Orlando , S. W. Digel