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The unsurpassed sensitivity and resolution of the Square Kilometer Array (SKA) will make it possible for the first time to probe the continuum emission of normal star forming galaxies out to the edges of the universe. This opens the…

Here we present a new non-parametric approach to density estimation and classification derived from theory in Radon transforms and image reconstruction. We start by constructing a "forward problem" in which the unknown density is mapped to…

Numerical Analysis · Mathematics 2024-12-20 James Webber , Erika Hussey , Eric Miller , Shuchin Aeron

We propose a new non-parametric method to constrain the cosmological model through the growth factor of large-scale structure. To constrain the cosmological model from observations such as cosmic microwave background or large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-19 Kiichi Yoshida , Kiyotomo Ichiki , Atsushi J. Nishizawa

We present the results of a new, non-parametric method to reconstruct the Galactic dark matter profile directly from observations. Using the latest kinematic data to track the total gravitational potential and the observed distribution of…

Astrophysics of Galaxies · Physics 2015-05-07 Miguel Pato , Fabio Iocco

The future new-generation radio telescope SKA (Square Kilometre Array) and its precursors will provide a rapidly growing number of polarized radio sources. Hundred and thousands polarized background sources can be measured towards nearby…

Astrophysics · Physics 2007-12-03 T. G. Arshakian , R. Stepanov , R. Beck , P. Frick , M. Krause

The practical success of density functional theory (DFT) is largely credited to the Kohn-Sham approach, which enables the exact calculation of the non-interacting electron kinetic energy via an auxiliary noninteracting system. Yet, the…

Computational Physics · Physics 2025-03-21 Sangita Majumdar , Zekun Shi , Giovanni Vignale

The Square Kilometre Array (SKA) will transform our understanding of the role of the cold, atomic gas in galaxy evolution. The interstellar medium (ISM) is the repository of stellar ejecta and the birthsite of new stars and, hence, a key…

We present a method to constrain galaxy parameters directly from three-dimensional data cubes. The algorithm compares directly the data with a parametric model mapped in $x,y,\lambda$ coordinates. It uses the spectral lines-spread function…

Instrumentation and Methods for Astrophysics · Physics 2015-09-01 N. Bouché , H. Carfantan , I. Schroetter , L. Michel-Dansac , T. Contini

The overwhelming foreground contamination hinders the accurate detection of the 21-cm signal of neutral hydrogen during the Epoch of Reionization (EoR). Among various foreground components, the Galactic free-free emission is less studied,…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-11 Xiaoli Lian , Haiguang Xu , Zhenghao Zhu , Dan Hu

A three-component Stackel model of the Galaxy, including the bulge, disk, and halo, is constructed. Parameter estimates of the potential are obtained as a result of fitting the model rotation curve to azimuthal velocities found from data on…

Astrophysics of Galaxies · Physics 2021-11-03 A. O. Gromov , I. I. Nikiforov

We present a cosmography analysis of the Local Universe based on the recently released Two-Micron All-Sky Redshift Survey (2MRS). Our method is based on a Bayesian Networks Machine Learning algorithm (the Kigen-code) which self-consistently…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-08 Francisco-Shu Kitaura , Pirin Erdogdu , Sebastian E. Nuza , Arman Khalatyan , Raul E. Angulo , Yehuda Hoffman , Stefan Gottloeber

The Square Kilometer Array (SKA) would be the world's largest radio telescope with eventually over a square kilometer of collecting area. However, there are enormous challenges in its data processing. The using of modern distributed…

Instrumentation and Methods for Astrophysics · Physics 2021-06-02 Shoulin Wei , Kaida Luo , Feng Wang , Hui Deng , Ying Mei

We present an extended morphometric system to automatically classify galaxies from astronomical images. The new system includes the original and modified versions of the CASGM coefficients (Concentration $C_1$, Asymmetry $A_3$, and…

Astrophysics of Galaxies · Physics 2015-09-21 Fabricio Ferrari , Reinaldo Ramos de Carvalho , Marina Trevisan

The Gridding algorithm has shown great utility for reconstructing images from non-uniformly spaced samples in the Fourier domain in several imaging modalities. Due to the non-uniform spacing, some correction for the variable density of the…

Image and Video Processing · Electrical Eng. & Systems 2021-06-17 Nicholas Dwork , Daniel O'Connor , Ethan M. I. Johnson , Corey A. Baron , Jeremy W. Gordon , John M. Pauly , Peder E. Z. Larson

Parallax measurements of pulsars allow for accurate measurements of the interstellar electron density and contribute to accurate tests of general relativity using binary systems. The Square Kilometre Array (SKA) will be an ideal instrument…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 R. Smits , S. J. Tingay , N. Wex , M. Kramer , B. Stappers

We present a self-consistent Bayesian formalism to sample the primordial density fields compatible with a set of dark matter density tracers after cosmic evolution observed in redshift space. Previous works on density reconstruction did not…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-09 E. G. Patrick Bos , Francisco-Shu Kitaura , Rien van de Weygaert

The Square Kilometre Array (SKA) will produce spectroscopic surveys of tens to hundreds of millions of HI galaxies, eventually covering 30,000 sq. deg. and reaching out to redshift z~2. The huge volumes probed by the SKA will allow for some…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-25 Stefano Camera , Mario G. Santos , Roy Maartens

Spectroscopic surveys such as the Dark Energy Spectroscopic Instrument (DESI) and Euclid are mapping the spatial distribution of millions of galaxies, with Emission Line Galaxies (ELGs) serving as the dominant tracer in the redshift range…

We present a new Bayesian non-parametric deprojection algorithm DOPING (Deprojection of Observed Photometry using and INverse Gambit), that is designed to extract 3-D luminosity density distributions $\rho$ from observed surface brightness…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Dalia Chakrabarty

Most observational studies of galactic-scale magnetic fields using Faraday rotation rely on estimates of thermal electron densities in galaxies and their radial variations. However, the spatial distribution of electrons in the interstellar…

Astrophysics of Galaxies · Physics 2026-02-23 Shivam Burman , Sunil Malik , Suprit Singh , Yogesh Wadadekar