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We present a novel application of partial convolutional neural networks (PCNN) that can inpaint masked images of the cosmic microwave background. The network can reconstruct both the maps and the power spectra to a few percent for circular…

天体物理仪器与方法 · 物理学 2021-03-19 Gabriele Montefalcone , Maximilian H. Abitbol , Darsh Kodwani , R. D. P. Grumitt

Recovering the polarized cosmic microwave background (CMB) is essential for shedding light on the exponential expansion of the very early Universe, known as cosmic inflation. Achieving this goal requires not only improved instrumental…

Next-generation cosmic microwave background (CMB) surveys are expected to provide valuable information about the primordial universe by creating maps of the mass along the line of sight. Traditional tools for creating these lensing…

宇宙学与河外天体物理 · 物理学 2022-05-17 Peikai Li , Ipek Ilayda Onur , Scott Dodelson , Shreyas Chaudhari

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

One of the principle efforts in cosmic microwave background (CMB) research is measurement of the parameter fnl that quantifies the departure from Gaussianity in a large class of non-minimal inflationary (and other) models. Estimators for…

宇宙学与河外天体物理 · 物理学 2015-05-27 Tristan L. Smith , Marc Kamionkowski , Benjamin D. Wandelt

We use Minkowski Functionals to explore the presence of non-Gaussian signatures in simulated cosmic microwave background (CMB) maps. Precisely, we analyse the non-Gaussianities produced from the angular power spectra emerging from a class…

宇宙学与河外天体物理 · 物理学 2023-03-08 Camila P. Novaes , Micol Benetti , Armando Bernui

Primordial non-Gaussianity is a sensitive probe of the inflationary era, with a number of important theoretical targets living an order of magnitude beyond the reach of current CMB constraints. Maps of the large-scale structure of the…

宇宙学与河外天体物理 · 物理学 2022-09-07 Daniel Baumann , Daniel Green

In order to extract cosmological information from observations of the millimeter and submillimeter sky, foreground components must first be removed to produce an estimate of the cosmic microwave background (CMB). We developed a…

宇宙学与河外天体物理 · 物理学 2020-11-10 Matthew A. Petroff , Graeme E. Addison , Charles L. Bennett , Janet L. Weiland

The fluctuations produced during cosmic inflation may exhibit non-Gaussian characteristics that are imprinted in the large-scale structure of the Universe. This non-Gaussian imprint is an ultra-large scale signal that can be detected using…

宇宙学与河外天体物理 · 物理学 2025-06-11 Mponeng Kopana , Sheean Jolicoeur , Roy Maartens

We present a novel method for Cosmic Microwave Background (CMB) foreground removal based on deep learning techniques. This method employs a Transformer model, referred to as \texttt{TCMB}, which is specifically designed to effectively…

宇宙学与河外天体物理 · 物理学 2025-10-09 Ye-Peng Yan , Si-Yu Li , Yang Liu , Jun-Qing Xia , Hong Li

We analyze non-Gaussianity (NG) due to the primordial bispectrum and trispectrum using CMB temperature maps of WMAP 7-year data. We first apply the perturbative formulae of Minkowski functionals up to second-order NG derived by Matsubara…

宇宙学与河外天体物理 · 物理学 2012-09-28 Chiaki Hikage , Takahiko Matsubara

Although cosmological observations suggest that the fluctuations of seed fields are almost Gaussian, the possibility of a small deviation of their fields from Gaussianity is widely discussed. Theoretically, there exist numerous inflationary…

宇宙学与河外天体物理 · 物理学 2022-09-21 Maresuke Shiraishi

The detection of primordial non-Gaussianity could provide a powerful means to test various inflationary scenarios. Although scale-invariant non-Gaussianity (often described by the $f_{NL}$ formalism) is currently best constrained by the…

天体物理学 · 物理学 2009-06-23 Marilena LoVerde , Amber Miller , Sarah Shandera , Licia Verde

Local non-Gaussianities in the initial conditions of the Universe, parameterized by $f_{\rm NL}$, induce a scale-dependence in the large-scale bias of halos in the late Universe. This effect is a promising path to constrain multi-field…

宇宙学与河外天体物理 · 物理学 2022-10-04 Fiona McCarthy , Mathew S. Madhavacheril , Abhishek S. Maniyar

The 21-cm brightness temperature fluctuation from the Dark Ages ($z \simeq 30-100$) will allow us to probe the inflationary epoch on very small scales ($>0.1 \, \mbox{Mpc}^{-1}$), inaccessible to cosmic microwave background experiments.…

宇宙学与河外天体物理 · 物理学 2023-07-28 Giorgio Orlando , Thomas Flöss , P. Daniel Meerburg , Joseph Silk

Primordial magnetic fields (PMFs) create a large squeezed-type non-Gaussianity in tensor perturbation, which generates non-Gaussian temperature fluctuations in the cosmic microwave background (CMB). We for the first time derive an…

宇宙学与河外天体物理 · 物理学 2014-11-13 Maresuke Shiraishi , Toyokazu Sekiguchi

Local primordial non-Gaussianity (LPNG) couples long-wavelength cosmological fluctuations to the short-wavelength behavior of galaxies. This coupling is encoded in bias parameters including $b_{\phi}$ and $b_{\delta\phi}$ at linear and…

宇宙学与河外天体物理 · 物理学 2025-02-11 James M. Sullivan , Shi-Fan Chen

Component separation is the process of extracting one or more emission sources in astrophysical maps. It is therefore crucial to develop models that can accurately clean the cosmic microwave background (CMB) in current and future…

宇宙学与河外天体物理 · 物理学 2025-04-17 J. M. Casas , L. Bonavera , J. González-Nuevo , G. Puglisi , C. Baccigalupi

We describe the subject of Cosmic Microwave Background (CMB) analysis - its past, present and future. The theory of Gaussian primary anisotropies, those arising from linear physics operating in the early Universe, is in reasonably good…

天体物理学 · 物理学 2010-05-12 J. Richard Bond , Robert G. Crittenden

Astrophysical images in the GeV band are challenging to analyze due to the strong contribution of the background and foreground astrophysical diffuse emission and relatively broad point spread function of modern space-based instruments. In…

计算机视觉与模式识别 · 计算机科学 2020-12-09 Mariia Drozdova , Anton Broilovskiy , Andrey Ustyuzhanin , Denys Malyshev
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