English
Related papers

Related papers: A Generative Reconstruction of Low-$\ell$ CMB B-Mo…

200 papers

We evaluate the ability of SPIDER, a balloon-borne polarimeter, to detect a divergence-free polarization pattern ("B-modes") in the Cosmic Microwave Background (CMB). In the inflationary scenario, the amplitude of this signal is…

Searching for the signal of primordial gravitational waves in the B-modes (BB) power spectrum is one of the key scientific aims of the cosmic microwave background (CMB) polarization experiments. However, this could be easily contaminated by…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Si-Yu Li , Jun-Qing Xia , Mingzhe Li , Hong Li , Xinmin Zhang

Cosmological Birefringence (CB), a rotation of the polarization plane of radiation coming to us from distant astrophysical sources, may reveal parity violation in either the electromagnetic or gravitational sectors of the fundamental…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Amit P. S. Yadav , Meir Shimon , Brian G. Keating

Diffusion models now set the benchmark in high-fidelity generative sampling, yet they can, in principle, be prone to memorization. In this case, their learned score overfits the finite dataset so that the reverse-time SDE samples are mostly…

Machine Learning · Computer Science 2025-05-30 Franck Gabriel , François Ged , Maria Han Veiga , Emmanuel Schertzer

One of the main goals of modern cosmology is to search for primordial gravitational waves by looking on their imprints in the B-type polarization in the cosmic microwave background radiation. However, this signal is contaminated by various…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Larissa Santos , Kai Wang , Yangrui Hu , Wenjuan Fang , Wen Zhao

Foreground masking and incomplete sky coverage complicate CMB polarization analyses by inducing mode coupling and imperfect E/B separation, with particularly strong impact on searches for primordial $B$-modes. We present SkyReconNet-P, a…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-17 Reyhan D. Lambaga , Vipin Sudevan , Pisin Chen

A new spin wavelet transform on the sphere is proposed to analyse the polarisation of the cosmic microwave background (CMB), a spin $\pm 2$ signal observed on the celestial sphere. The scalar directional scale-discretised wavelet transform…

Instrumentation and Methods for Astrophysics · Physics 2014-12-04 Jason D. McEwen , Martin Büttner , Boris Leistedt , Hiranya V. Peiris , Pierre Vandergheynst , Yves Wiaux

Score-based diffusion models learn to reverse a stochastic differential equation that maps data to noise. However, for complex tasks, numerical error can compound and result in highly unnatural samples. Previous work mitigates this drift…

Machine Learning · Statistics 2023-06-12 Aaron Lou , Stefano Ermon

We present a novel approach to reconstruct gas and dark matter projected density maps of galaxy clusters using score-based generative modeling. Our diffusion model takes in mock SZ and X-ray images as conditional inputs, and generates…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-16 Alan Hsu , Matthew Ho , Joyce Lin , Carleen Markey , Michelle Ntampaka , Hy Trac , Barnabás Póczos

Gravitational waves from inflation induce polarization patterns in the cosmic microwave background (CMB). It is known that there are only two types of non-Gaussianities of the gravitaional waves in the most general scalar field theories…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 Hiroaki W. H. Tahara , Jun'ichi Yokoyama

Incomplete sky analysis of cosmic microwave background (CMB) polarization spectra poses a major problem of leakage between $E$- and $B$-modes. We present a machine learning approach to remove this $E$-to-$B$ leakage using a convolutional…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-02 Srikanta Pal , Rajib Saha

Contamination by polarized foregrounds is one of the biggest challenges for future polarized cosmic microwave background (CMB) surveys and the potential detection of primordial $B$-modes. Future experiments, such as Simons Observatory (SO)…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-12 Carlos Hervías-Caimapo , Anna Bonaldi , Michael L. Brown , Kevin M. Huffenberger

The detection of primordial $B$-mode polarisation of the Cosmic Microwave Background (CMB) is a major observational goal in modern Cosmology, offering a potential window into inflationary physics through the measurement of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-22 Claudio Ranucci , Alessandro Carones , Léo Vacher , Nicoletta Krachmalnicoff , Carlo Baccigalupi

We present measurements of large-scale cosmic microwave background (CMB) E-mode polarization from the Cosmology Large Angular Scale Surveyor (CLASS) 90 GHz data. Using 115 det-yr of observations collected through 2024 with a variable-delay…

String models can produce successful inflationary scenarios in the context of brane collisions and in many of these models cosmic strings may also be produced. In scenarios such as KKLMMT the string contribution is naturally predicted to be…

Astrophysics · Physics 2009-11-11 Uros Seljak , Anze Slosar

We analyze the possibility of delensing CMB polarization maps using foreground weak lensing (WL) information. We build an estimator of the CMB lensing potential out of optimally combined projected potential estimators to different source…

Astrophysics · Physics 2008-11-26 Laura Marian , Gary M. Bernstein

Future Cosmic Microwave Background (CMB) satellite missions aim to use the $B$ mode polarization to measure the tensor-to-scalar ratio $r$ with a sensitivity of about $10^{-3}$. Achieving this goal will not only require sufficient detector…

The detection of the magnetic type $B$-mode polarization is the main goal of future cosmic microwave background (CMB) experiments. In the standard model, the $B$-mode map is a strongly non-gaussian field due to the lensed component. Besides…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-20 Larissa Santos , Kai Wang , Wen Zhao

Cosmic Microwave Background (CMB) lensing is a powerful probe of the matter distribution in the Universe. The standard quadratic estimator, which is typically used to measure the lensing signal, is known to be suboptimal for low-noise…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-26 Benjamin Horowitz , Simone Ferraro , Blake D. Sherwin
‹ Prev 1 8 9 10 Next ›