English
Related papers

Related papers: How to avoid X'es around point sources in maximum …

200 papers

Time-ordered data (TOD) from ground-based CMB experiments are generally filtered before map-making to remove or reduce the contamination from the ground and the atmospheric emissions. However, when the observation region contains strong…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-28 Zhaoxuan Zhang , Lu Huang , Yang Liu , Si-Yu Li , Le Zhang , Hao Liu

Point-source contamination in high-precision Cosmic Microwave Background (CMB) maps severely affects the precision of cosmological parameter estimates. Among the methods that have been proposed for source detection, wavelet techniques based…

Astrophysics · Physics 2009-11-07 R. Vio , L. Tenorio , W. Wamsteker

We discuss point sources foregrounds for the MAP experiment. We consider several possible strategies for removing them and we assess how the statistics of the CMB signal are affected by the residual sources. Assuming a power law…

Astrophysics · Physics 2009-11-07 Elena Pierpaoli

Map-making presents a significant computational challenge to the next generation of kilopixel CMB polarisation experiments. Years worth of time ordered data (TOD) from thousands of detectors will need to be compressed into maps of the T, Q…

Astrophysics · Physics 2009-02-16 D. Sutton , B. R. Johnson , M. L. Brown , P. Cabella , P. G. Ferreira , K. M. Smith

We address in this work the instrumental systematic errors that can potentially affect the forthcoming and future Cosmic Microwave Background experiments aimed at observing its polarized emission. In particular, we focus on the systematics…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-14 Giuseppe Puglisi , Reijo Keskitalo , Ted Kisner , Julian D. Borrill

A maximum likelihood (ML) technique for detecting compact sources in images of the x-ray sky is examined. Such images, in the relatively low exposure regime accessible to present x-ray observatories, exhibit Poissonian noise at background…

Instrumentation and Methods for Astrophysics · Physics 2009-11-13 I. M. Stewart

For high-precision cosmic microwave background (CMB) experiments, contamination from extragalactic point sources is a major concern. It is therefore useful to be able to detect and discard point source contaminated pixels using the map…

Astrophysics · Physics 2009-10-30 Max Tegmark , Angelica de Oliveira-Costa

Noise maps from CMB experiments are generally statistically anisotropic, due to scanning strategies, atmospheric conditions, or instrumental effects. Any mis-modeling of this complex noise can bias the reconstruction of the lensing…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-03 Louis Legrand , Blake Sherwin , Anthony Challinor , Julien Carron , Gerrit S. Farren

Many surveys use maximum-likelihood (ML) methods to fit models when extracting photometry from images. We show these ML estimators systematically overestimate the flux as a function of the signal-to-noise ratio and the number of model…

Instrumentation and Methods for Astrophysics · Physics 2020-03-25 Stephen K. N. Portillo , Joshua S. Speagle , Douglas P. Finkbeiner

Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

Astrophysics · Physics 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

The detection and flux estimation of point sources in cosmic microwave background (CMB) maps is a very important task in order to clean the maps and also to obtain relevant astrophysical information. In this paper we propose a maximum a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 F. Argueso , E. Salerno , D. Herranz , J. L. Sanz , E. E. Kuruoglu , K. Kayabol

CMB data analysis is in general done through two main steps : map-making of the time data streams and power spectrum extraction from the maps. The latter basically consists in the separation between the variance of the CMB and that of the…

Astrophysics · Physics 2007-05-23 J. -Ch. Hamilton

Pointwise maximal leakage (PML) is an operationally meaningful privacy measure that quantifies the amount of information leaking about a secret $X$ to a single outcome of a related random variable $Y$. In this paper, we extend the notion of…

Information Theory · Computer Science 2023-04-18 Sara Saeidian , Giulia Cervia , Tobias J. Oechtering , Mikael Skoglund

We study the information leakage to a guessing adversary in zero-error source coding. The source coding problem is defined by a confusion graph capturing the distinguishability between source symbols. The information leakage is measured by…

Information Theory · Computer Science 2021-02-04 Yucheng Liu , Lawrence Ong , Sarah Johnson , Joerg Kliewer , Parastoo Sadeghi , Phee Lep Yeoh

AIMS. The maximum-likelihood method is the standard approach to obtain model fits to observational data and the corresponding confidence regions. We investigate possible sources of bias in the log-likelihood function and its subsequent…

Astrophysics · Physics 2009-11-11 J. Hartlap , P. Simon , P. Schneider

Future Cosmic Microwave Background (CMB) satellite missions aim at using the B-mode polarisation signal to measure the tensor-to-scalar ratio $r$ with a sensitivity $\sigma(r)$ of the order of $\leq 10^{-3}$. Small uncertainties in the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-07 Ranajoy Banerji , Guillaume Patanchon , Jacques Delabrouille , Masashi Hazumi , Duc Thuong Hoang , Hirokazu Ishino , Tomotake Matsumura

CMB mapmaking relies on a data model to solve for the sky map, and this process is vulnerable to bias if the data model cannot capture the full behavior of the signal. We demonstrate that this bias is not just limited to small-scale effects…

Instrumentation and Methods for Astrophysics · Physics 2024-08-30 Sigurd Naess , Thibaut Louis

The next generation of CMB experiments can measure cosmological parameters with unprecedented accuracy - in principle. To achieve this in practice when faced with such gigantic data sets, elaborate data analysis methods are needed to make…

Astrophysics · Physics 2009-10-28 Max Tegmark

The detection of point-sources in microwave maps is a critical step in the analysis of the Cosmic Microwave Background (CMB) data. If not properly removed, these sources have adverse effects on the estimation of the power-spectrum and/or…

Astrophysics · Physics 2009-07-14 R. Vio , P. Andreani

Maximal leakage quantifies the leakage of information from data $X \in \mathcal{X}$ due to an observation $Y$. While fundamental properties of maximal leakage, such as data processing, sub-additivity, and its connection to mutual…

Information Theory · Computer Science 2025-12-24 Anuran Makur , Japneet Singh
‹ Prev 1 2 3 10 Next ›