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Related papers: Epoch of reionization parameter estimation with th…

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Cosmic Reionization imprints its signature on the temperature and polarization anisotropies of the cosmic microwave background (CMB). Advances in CMB telescopes have already placed a significant constraint on the history of reionization. As…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 Hina Sakamoto , Kyungjin Ahn , Kiyotomo Ichiki , Hyunjin Moon , Kenji Hasegawa

We explore the information content of 21cm intensity maps in redshift space using the 1-loop Effective Field Theory power spectrum model and the bispectrum at tree level. The 21cm signal contains signatures of dark matter, dark energy and…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 Liantsoa F. Randrianjanahary , Dionysios Karagiannis , Roy Maartens

The residual gain errors add to the systematics of the radio interferometric observations. In case of the high dynamic range observations, these systematic effects dominates over the thermal noise of the observation. In this work, we…

Instrumentation and Methods for Astrophysics · Physics 2021-01-13 Jais Kumar , Prasun Dutta , Nirupam Roy

Improvements in current instruments and the advent of next-generation instruments will soon push observational 21 cm cosmology into a new era, with high significance measurements of both the power spectrum and the mean ("global") signal of…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-08 Adrian Liu , Aaron R. Parsons

We have made a Markov Chain Monte Carlo (MCMC) analysis of primordial non-Gaussianity (f_NL) using the WMAP bispectrum and power spectrum. In our analysis, we have simultaneously constrained f_NL and cosmological parameters so that the…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-27 Jaiseung Kim

We study constraints on allowed reionization histories by comparing predictions of a physical semi-numerical model with secondary temperature and polarization anisotropies of the cosmic microwave background (CMB). Our model has four free…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-02 Tirthankar Roy Choudhury , Suvodip Mukherjee , Sourabh Paul

We present a new approach to parameter inference targeted on generic situations where the evaluation of the likelihood $\mathcal{L}$ (i.e., the probability to observe the data given a fixed model configuration) is numerically expensive.…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 Aseem Paranjape

Spatial variations in the Lyman-$\alpha$ forest opacity at $z<6$ seem to require a late end to cosmic reionization. In this picture, the universe contains neutral hydrogen 'islands' of up to 100 cMpc$/h$ in extent down to redshifts as low…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-06 Janakee Raste , Girish Kulkarni , Catherine A. Watkinson , Laura C. Keating , Martin G. Haehnelt

In this article we consider Bayesian estimation of static parameters for a class of partially observed McKean-Vlasov diffusion processes with discrete-time observations over a fixed time interval. This problem features several obstacles to…

Computation · Statistics 2025-04-23 Ajay Jasra , Amin Wu

We propose algorithms for addressing the bias of the posterior mean when used as an estimator of parameters. These algorithms build upon the recently proposed Bayesian infinitesimal jackknife approximation (Giordano and Broderick (2023))…

Methodology · Statistics 2024-09-06 Yukito Iba

BICEP1 is a millimeter-wavelength telescope designed specifically to measure the inflationary B-mode polarization of the Cosmic Microwave Background (CMB) at degree angular scales. We present results from an analysis of the data acquired…

Forthcoming cosmic shear surveys will make precise measurements of the matter density field down to very small scales, scales which are dominated by baryon feedback. The modelling of baryon feedback is crucial to ensure unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 Alessandro Maraio , Alex Hall , Andy Taylor

Isocurvature perturbations expected from multi-field inflation models can leave unique signatures in the early Universe, but remain weakly constrained, especially on small scales. In this work, we investigate the constraining power of…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-19 Zhenfei Qin , Hayato Shimabukuro

Lensing of the CMB generates a significant bispectrum, which should be detected by the Planck satellite at the 5-sigma level and is potentially a non-negligible source of bias for f_NL estimators of local non-Gaussianity. We extend current…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Antony Lewis , Anthony Challinor , Duncan Hanson

The detection of the primordial $B$-mode spectrum of the polarized cosmic microwave background (CMB) signal may provide a probe of inflation. However, observation of such a faint signal requires excellent control of systematic errors.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Ata Karakci , Le Zhang , P. M. Sutter , Emory F. Bunn , Andrei Korotkov , Peter Timbie , Gregory S. Tucker , Benjamin D. Wandelt

In this paper, we present a method for computing the marginal likelihood, also known as the model likelihood or Bayesian evidence, from Markov Chain Monte Carlo (MCMC), or other sampled posterior distributions. In order to do this, one…

A possible way to study the reionization of cosmic hydrogen is by observing the large ionized regions (bubbles) around bright individual sources, e.g., quasars, using the redshifted 21 cm signal. It has already been shown that matched…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Raghunath Ghara , T. Roy Choudhury

A large number of statistical models are "doubly-intractable": the likelihood normalising term, which is a function of the model parameters, is intractable, as well as the marginal likelihood (model evidence). This means that standard…

Methodology · Statistics 2015-12-11 Anne-Marie Lyne , Mark Girolami , Yves Atchadé , Heiko Strathmann , Daniel Simpson

We describe a Bayesian framework for estimating the time-domain noise covariance of CMB observations, typically parametrized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 I. K. Wehus , S. K. Næss , H. K. Eriksen

We compute robust lower limits on the spin temperature, $T_{\rm S}$, of the $z=8.4$ intergalactic medium (IGM), implied by the upper limits on the 21-cm power spectrum recently measured by PAPER-64. Unlike previous studies which used a…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Bradley Greig , Andrei Mesinger , Jonathan C. Pober