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The low density nuclear matter equation of state is strongly constrained by nuclear properties, however, for constraining the high density equation of state it is necessary to resort to indirect information obtained from the observation of…

Nuclear Theory · Physics 2021-10-04 Márcio Ferreira , Constança Providência

We investigate the ability of basis function expansions to reproduce the evolution of a Milky Way-like dark matter halo, extracted from a cosmological zoom-in simulation. For each snapshot, the density of the halo is reduced to a basis…

Astrophysics of Galaxies · Physics 2020-10-14 J. L. Sanders , E. J. Lilley , E. Vasiliev , N. W. Evans , D. Erkal

This paper studies ordered weighted L1 (OWL) norm regularization for sparse estimation problems with strongly correlated variables. We prove sufficient conditions for clustering based on the correlation/colinearity of variables using the…

Machine Learning · Statistics 2014-09-16 Mario A. T. Figueiredo , Robert D. Nowak

We consider three extensions of the Navarro, Frenk and White (NFW) profile and investigate the intrinsic degeneracies among the density profile parameters on the gravitational lensing effect of satellite galaxies on highly magnified…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Simona Vegetti , Mark Vogelsberger

Context. Recently our ability to study stars using asteroseismic techniques has increased dramatically, largely through the use of space based photometric observations. Work has also been done using ground based spectroscopic observations…

Solar and Stellar Astrophysics · Physics 2018-10-03 Jesper Schou

Next-generation cosmological surveys will observe larger cosmic volumes than ever before, enabling us to access information on the primordial Universe, as well as on relativistic effects. We consider forthcoming 21cm intensity mapping…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-08 Jan-Albert Viljoen , José Fonseca , Roy Maartens

To mitigate inter-satellite interference and payload limits in LEO mega-constellations, satellite clusters, groups of small cooperative satellites have been proposed to improve performance and reduce interference. The typical configuration…

Information Theory · Computer Science 2026-04-03 Juanjuan Ru , Ruibo Wang , Mohamed-Slim Alouini

Aiming to extract cosmological information from linear scales of the WISE$\times$SuperCOSMOS photometric redshift catalog, we perform a characterization of the systematic effects associated with stellar content, evidencing the presence of…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-11 H. S. Xavier , M. V. Costa-Duarte , A. Balaguera-Antolínez , M. Bilicki

Effective ground station selection is critical for low Earth orbiting (LEO) satellite constellations to minimize operational costs, maximize data downlink volume, and reduce communication gaps between access windows. Traditional ground…

Networking and Internet Architecture · Computer Science 2025-10-07 Grace Ra Kim , Duncan Eddy , Vedant Srinivas , Mykel J. Kochenderfer

We consider the problem of covert communication over continuous-time additive white Gaussian noise (AWGN) channels under spectral mask constraints, wherein two legitimate parties attempt to communicate reliably in the presence of an…

Information Theory · Computer Science 2020-01-07 Qiaosheng , Zhang , Matthieu R. Bloch , Mayank Bakshi , Sidharth Jaggi

This paper investigates the maximum achievable downlink spectral efficiency of low Earth orbit (LEO) satellite constellations. Spectral efficiency is defined here as the total network sum rate per unit bandwidth per unit area of Earth's…

Signal Processing · Electrical Eng. & Systems 2025-11-11 Cuneyd Ozturk , Dongning Guo , Randall A. Berry , Michael L. Honig

Loop percolation, also known as the dense O(1) loop model, is a variant of critical bond percolation in the square lattice Z^2 whose graph structure consists of a disjoint union of cycles. We study its connectivity pattern, which is a…

Probability · Mathematics 2015-06-15 Dan Romik

End-to-end latency in large low-Earth-orbit (LEO) constellations is dominated by propagation delay, making total delay roughly proportional to the network diameter, the longest shortest path in hops. Current inter-satellite link (ISL)…

Networking and Internet Architecture · Computer Science 2026-01-12 Arman Mollakhani , Jerayu Tiamraj , Shu-Jie Cao , Dongning Guo

Simple parameter-free analytic bias functions for the two-point correlation of densities in spheres at large separation are presented. These bias functions generalize the so-called Kaiser bias to the mildly non-linear regime for arbitrary…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-19 C. Uhlemann , S. Codis , J. Kim , C. Pichon , F. Bernardeau , D. Pogosyan , C. Park , B. L'Huillier

With the ever-increasing lunar missions, a growing interest develops in designing data relay satellite constellations for cislunar communications, which is challenged by the constrained visibility and huge distance between the earth and…

Networking and Internet Architecture · Computer Science 2024-11-11 Afang Yuan , Zhouyong Hu , Zhili Sun , Qinyu Zhang , Zhihua Yang

Injecting artificial noise (AN) along the tangent space of a curved constellation makes each transmitted symbol induce a Gaussian observation with a symbol-dependent rank-one covariance, so the matched maximum-likelihood (ML) decoder…

Information Theory · Computer Science 2026-04-29 Bin Han , Muxia Sun , H. Vincent Poor , Hans D. Schotten

Delivering broadband connectivity to unconnected areas is extremely challenging. The emergence of Low Earth Orbit (LEO) satellite systems has been seen as a potential solution for connecting remote areas. Despite the hype around these new…

Systems and Control · Electrical Eng. & Systems 2021-08-25 Osoro B. Ogutu , Edward J. Oughton

Low Earth orbit (LEO) mega-constellations greatly extend the coverage and resilience of future wireless systems. Within the mega-constellations, laser inter-satellite links (LISLs) enable high-capacity, long-range connectivity. Existing…

Signal Processing · Electrical Eng. & Systems 2026-01-30 Zhouyou Gu , Jihong Park , Jinho Choi

AIMS. We calculate the stellar density using star counts obtained from Gaia DR2 up to a Galactocentric distance R=20 kpc with a deconvolution technique for the parallax errors. Then we analyse the density in order to study the structure of…

Astrophysics of Galaxies · Physics 2020-05-27 Z. Chrobakova , R. Nagy , M. Lopez-Corredoira

The need to carry out analytical studies of wireless systems often motivates the usage of simplified models which, despite their tractability, can easily lead to an overestimation of the achievable performance. In the case of dense small…

Information Theory · Computer Science 2015-06-08 Carlo Galiotto , Nuno K. Pratas , Nicola Marchetti , Linda Doyle