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We present ECLIPSE (Efficient Cmb poLarization and Intensity Power Spectra Estimator), an optimized implementation of the Quadratic Maximum Likelihood (QML) method for the estimation of the power spectra of the Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-02 J. D. Bilbao-Ahedo , R. B. Barreiro , P. Vielva , E. Martínez-González , D. Herranz

Computer model calibration is a crucial step in building a reliable computer model. In the face of massive physical observations, a fast estimation for the calibration parameters is urgently needed. To alleviate the computational burden, we…

Statistics Theory · Mathematics 2022-11-24 Shurui Lv , Yan Wang , Jun Yu

The $\Lambda$ cold dark matter ($\Lambda\textrm{CDM}$) model is currently known as the simplest cosmology model that best describes observations with minimal number of parameters. Here we introduce a cosmology model that is preferred over…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Chan-Gyung Park

We present a fully parallelized grid-based parameter estimation algorithm for investigating multidimensional likelihoods called Snake, and apply it to cosmological parameter estimation. The basic idea is to map out the likelihood grid-cell…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 K. Mikkelsen , S. K. Næss , H. K. Eriksen

To improve the accuracy and efficiency of high-dimensional stellar parameter inference in large spectroscopic datasets, we propose a projection-assisted parameter-inference framework -- Projected-Space Inference of Stellar Parameters…

Numerical heating in particle-in-cell (PIC) codes currently precludes the accurate simulation of cold, relativistic plasma over long periods, severely limiting their applications in astrophysical environments. We present a spatially…

The Standard Model of Particle Physics (SMPP) is an enormously successful description of high energy physics, driving ever more precise measurements to find "physics beyond the standard model", as well as providing motivation for developing…

Astrophysics · Physics 2015-06-24 Douglas Scott

Aims: The interactive software package iCosmo, designed to perform cosmological calculations is described. Methods: iCosmo is a software package to perform interactive cosmological calculations for the low redshift universe. Computing…

Astrophysics · Physics 2015-05-13 Alexandre Refregier , Adam Amara , Thomas Kitching , Anais Rassat

Constructing a fast and efficient estimator for the B-mode power spectrum of cosmic microwave background (CMB) is of critical importance for CMB science. For a general CMB survey, the Quadratic Maximum Likelihood (QML) estimator for CMB…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Jiming Chen , Shamik Ghosh , Hao Liu , Larissa Santos , Wenjuan Fang , Siyu Li , Yang Liu , Hong Li , Jiaxin Wang , Le Zhang , Bin Hu , Wen Zhao

We discuss the problem of constraining cosmological parameters with cosmic microwave background band--power estimates. Because these latter are variances, they do not have gaussian distribution functions and, hence, the standard…

Astrophysics · Physics 2007-05-23 J. G. Bartlett , A. Blanchard , M. Douspis , M. Le Dour

In a previous paper (part I), the mathematical properties of the cosmic microwave background radiation power spectrum which presents oscillations were discussed. Here, we discuss the physical interpretation: a power spectrum with…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-28 Martin Lopez-Corredoira

The internal linear combination (ILC) method is a popular approach for constructing component-separated maps in cosmic microwave background (CMB) analyses. It optimally combines observed maps at different frequencies to produce an unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-05 Kristen M. Surrao , J. Colin Hill

We propose a new high dimensional semiparametric principal component analysis (PCA) method, named Copula Component Analysis (COCA). The semiparametric model assumes that, after unspecified marginally monotone transformations, the…

Machine Learning · Statistics 2014-02-20 Fang Han , Han Liu

Determination of cosmological parameters is a major goal in cosmology at present. The availability of improved data sets necessitates the development of novel statistical tools to interpret the inference from a cosmological model. In this…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Ranbir Sharma , H K Jassal

Using COBE-DMR 4-year data, we find a general expression yielding the likelihood distribution in the 3-dimensional parameter space spanned by the spectral index $n$, the spectral amplitude $a_{10}$ and the false-vacuum density parameter…

Astrophysics · Physics 2009-11-06 Marco Tucci , Angela Contaldo , Silvio Bonometto

We undertake a thorough search for signatures of sharp oscillatory features in the WMAP9 power spectrum and bispectrum as well as in the Planck power spectrum. For the first time, we carry out searches in both the power spectrum and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-27 J. R. Fergusson , H. F. Gruetjen , E. P. S. Shellard , B. Wallisch

Although cosmic microwave background (CMB) anisotropy data alone cannot constrain simultaneously the spatial curvature and the equation of state of dark energy, CMB data provide a valuable addition to other experimental results. However…

Astrophysics · Physics 2008-11-26 Pia Mukherjee , Martin Kunz , David Parkinson , Yun Wang

We use an iterative generalized least squares map-making algorithm, in conjunction with Monte Carlo techniques, to obtain estimates of the angular power spectrum from cosmic microwave background (CMB) maps. This is achieved by…

Astrophysics · Physics 2009-11-07 A. Balbi , G. de Gasperis , P. Natoli , N. Vittorio

Recently, two issues concerning the three-year WMAP likelihood code were pointed out. On large angular scales ($l \lesssim 30$), a sub-optimal likelihood approximation resulted in a small power excess. On small angular scales ($l \gtrsim…

Astrophysics · Physics 2007-05-23 Jostein R. Kristiansen , Hans Kristian Eriksen , Oystein Elgaroy

In the following article we provide an exposition of exact computational methods to perform parameter inference from partially observed network models. In particular, we consider the duplication attachment (DA) model which has a likelihood…

Computation · Statistics 2013-06-20 Junshan Wang , Ajay Jasra , Maria De Iorio
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