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Recently a symmetry-based method to test for statistical isotropy of the cosmic microwave background was developed. We apply the method to template-cleaned 3-year and 5-year WMAP-$DA$ maps. We examine a wide range of angular multipoles from…

Astrophysics · Physics 2010-11-02 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

The Cosmic Radio Dipole is of fundamental interest to cosmology. Recent studies revealed open questions about the nature of the observed Cosmic Radio Dipole. We use simulated source count maps to test a linear and a quadratic estimator for…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-07 Thilo M. Siewert , Matthias Schmidt-Rubart , Dominik J. Schwarz

A new smoothing method for the improvement on the identification and quantification of spectral functions based on the previous knowledge of the signals that are expected to be quantified, is presented. These signals are used as weighted…

Atomic Physics · Physics 2017-01-31 Leonardo Bennun

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…

Astrophysics · Physics 2008-11-26 Wayne Hu , Martin White

Electromagnetic interaction between a sub-wavelength particle (the `probe') and a material surface (the `sample') is studied theoretically. The interaction is shown to be governed by a series of resonances corresponding to surface polariton…

Mesoscale and Nanoscale Physics · Physics 2016-02-11 B. -Y. Jiang , L. M. Zhang , A. H. Castro Neto , D. N. Basov , M. M. Fogler

Results on the spectral behavior of random matrices as the dimension increases are applied to the problem of detecting the number of sources impinging on an array of sensors. A common strategy to solve this problem is to estimate the…

Statistics Theory · Mathematics 2022-12-09 J. W. Silverstein , P. L. Combettes

Aims. We present simulations of the perfomances of the future SPHERE IFS instrument designed for imaging extrasolar planets in the near infrared (Y, J, and H bands). Methods. We used the IDL package code for adaptive optics simulation…

Instrumentation and Methods for Astrophysics · Physics 2018-12-05 D. Mesa , R. Gratton , A. Berton , J. Antichi , C. Verinaud , A. Boccaletti , M. Kasper , R. U. Claudi , S. Desidera , E. Giro , J. -L. Beuzit , K. Dohlen , M. Feldt , D. Mouillet , G. Chauvin , A. Vigan

The integrating sphere (IS) is an indispensable tool for measuring transmission and scattering of materials and their colorimetry, as well as other photometric tasks. The accuracy of its data depends critically on port sizes used for…

Optics · Physics 2023-09-28 A. M. Bratkovsky

A lighting-based multispectral imaging system using an RGB camera and a projector is one of the most practical and low-cost systems to acquire multispectral observations for estimating the scene's spectral reflectance information. However,…

Image and Video Processing · Electrical Eng. & Systems 2020-12-21 Hironori Hidaka , Yusuke Monno , Masatoshi Okutomi

We propose a decomposition method for the spectral peaks in an observed frequency spectrum, which is efficiently acquired by utilizing the Fast Fourier Transform. In contrast to the traditional methods of waveform fitting on the spectrum,…

Signal Processing · Electrical Eng. & Systems 2022-04-19 Kaan Gokcesu , Hakan Gokcesu

The currently operating space missions, as well as those that will be launched in the near future, (will) deliver high-quality data for millions of stellar objects. Since the majority of stellar astrophysical applications still (at least…

Solar and Stellar Astrophysics · Physics 2015-09-23 Andrew Tkachenko

Microscopy research often requires recovering particle-size distributions in three dimensions from only a few (10 - 200) profile measurements in the section. This problem is especially relevant for petrographic and mineralogical studies,…

Methodology · Statistics 2022-02-16 Ekaterina Poliakova

Spectral retrieval techniques are currently our best tool to interpret the observed exoplanet atmospheric data. Said techniques retrieve the optimal atmospheric components and parameters by identifying the best fit to an observed…

Earth and Planetary Astrophysics · Physics 2020-10-21 Kai Hou Yip , Ingo P. Waldmann , Angelos Tsiaras , Giovanna Tinetti

We discuss methods for estimating EB and TB spectra of the Cosmic Microwave Background anisotropy maps covering limited sky area. Such odd-parity correlations are expected to vanish whenever parity is not broken. As this is indeed the case…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-18 Julien Grain , Matthieu Tristram , Radek Stompor

We discuss the effects of finite sky coverage and the uncertainty in extracting information about the power spectrum from experiments on small angular scales. In general the cosmic variance is enhanced by a factor of $4\pi/A$, where $A$ is…

Astrophysics · Physics 2009-10-22 Douglas Scott , Mark Srednicki , Martin White

Band-trellis enumerative sphere shaping is proposed to decrease the energy variations in channel input sequences. Against sphere shaping, 0.74 dB SNR gain and up to 9% increase in data rates are demonstrated for single-span systems.

Signal Processing · Electrical Eng. & Systems 2022-01-11 Yunus Can Gültekin , Alex Alvarado , Olga Vassilieva , Inwoong Kim , Paparao Palacharla , Chigo Okonkwo , Frans M. J. Willems

Within the well-established optical response function formalism, a new strategy with the central idea of employing the forward-backward stochastic Schr\"{o}dinger equations in a segmented way to accurately obtain the two-dimensional (2D)…

Chemical Physics · Physics 2018-08-08 Yaling Ke , Yi Zhao

The COBE satellite has provided the only comprehensive multi-frequency full-sky observations of the microwave sky available today. Assessment of the observations requires a detailed likelihood analysis to extract the maximum amount of…

Astrophysics · Physics 2007-05-23 K. M. Gorski

We compute the spectra of the adjacency matrices of the semi-regular polytopes. A few different techniques are employed: the most sophisticated, which relates the 1-skeleton of the polytope to a Cayley graph, is based on methods akin to…

Combinatorics · Mathematics 2007-05-23 Nicolau C. Saldanha , Carlos Tomei
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