English
Related papers

Related papers: Systematics mitigation for catalogue-based angular…

200 papers

The reconstruction of the CMBR power spectrum from a map represents a major computational challenge to which much effort has been applied. However, once the power spectrum has been recovered there still remains the problem of extracting…

Astrophysics · Physics 2009-12-30 Steen Hannestad

We introduce a formalism to solve the problem of photon scattering from a system of multi-level quantum emitters. Our approach provides a direct solution of the scattering dynamics. As such the formalism gives the scattered fields…

Quantum Physics · Physics 2018-04-25 Sumanta Das , Vincent E. Elfving , Florentin Reiter , Anders S. Sørensen

In this paper we derive a full expression for the propagation of weak lensing shape measurement biases into cosmic shear power spectra including the effect of missing data. We show using simulations that terms higher than first order in…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-16 T. D. Kitching , A. C. Deshpande , P. L. Taylor

Real photonic devices are subject to photon losses that can decohere quantum information encoded in the system. In the absence of full fault tolerance, quantum error mitigation techniques have been introduced to help manage errors in noisy…

Quantum Physics · Physics 2025-01-16 Adam Taylor , Gabriele Bressanini , Hyukjoon Kwon , M. S. Kim

In a companion paper we have reported a $>5\sigma$ detection of degree scale $B $-mode polarization at 150 GHz by the BICEP2 experiment. Here we provide a detailed study of potential instrumental systematic contamination to that…

Polarisation amplitude estimation is affected by a positive noise bias, particularly important in regions with low signal-to-noise ratio (SNR). We present a new approach to correct for this bias in the case there is additional information…

Instrumentation and Methods for Astrophysics · Physics 2016-06-29 Matias Vidal , J. P. Leahy , C. Dickinson

Upcoming Large Scale Structure surveys aim to achieve an unprecedented level of precision in measuring galaxy clustering. However, accurately modeling these statistics may require theoretical templates that go beyond second-order…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-21 M. Icaza-Lizaola , Yong-Seon Song , Minji Oh , Yi Zheng

We use numerical simulations of ray tracing through N-body simulations to investigate weak lensing by large-scale structure. These are needed for testing the analytic predictions of two-point correlators, to set error estimates on them and…

Astrophysics · Physics 2007-05-23 Bhuvnesh Jain , Uros Seljak , Simon White

Shadowing trajectories are model trajectories consistent with a sequence of observations of a system, given a distribution of observational noise. The existence of such trajectories is a desirable property of any forecast model. Gradient…

Data Analysis, Statistics and Probability · Physics 2019-09-16 Roland M. B. Young , Roman Binter , Falk Niehörster , Peter L. Read , Leonard A. Smith

We present a framework for inferring an atmospheric transmission profile from a spectral scene. This framework leverages a lightweight, physics-based simulator that is automatically tuned - by virtue of autodifferentiation and…

Machine Learning · Computer Science 2024-05-01 James Koch , Brenda Forland , Bruce Bernacki , Timothy Doster , Tegan Emerson

I present a new technique for the measurement of the growth of cosmic structures via the power spectrum of weak lensing cosmic shear. It is based on a template-fitting approach, where a redshift-dependent amplitude of lensing modulates a…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-09 Stefano Camera

We present a novel projection-based model reduction framework for parametric linear time-invariant systems that allows interpolating the transfer function at a given frequency point along parameter-dependent curves as opposed to the…

Numerical Analysis · Mathematics 2021-04-05 Ion Victor Gosea , Serkan Gugercin , Benjamin Unger

Welch's method provides an estimator of the power spectral density that is statistically consistent. This is achieved by averaging over periodograms calculated from overlapping segments of a time series. For a finite length time series,…

Methodology · Statistics 2024-04-12 Lachlan C. Astfalck , Adam M. Sykulski , Edward J. Cripps

We describe a method for computing the biases that systematic signals introduce in parameter estimation using a simple extension of the Fisher matrix formalism. This allows us to calculate the offset of the best fit parameters relative to…

Astrophysics · Physics 2009-11-13 Adam Amara , Alexandre Refregier

A new formalism is derived for the analysis and exact reconstruction of band-limited signals on the sphere with directional wavelets. It represents an evolution of the wavelet formalism developed by Antoine & Vandergheynst (1999) and Wiaux…

Astrophysics · Physics 2008-12-09 Y. Wiaux , J. D. McEwen , P. Vandergheynst , O. Blanc

This work concerns noise reduction for one-dimensional spectra in the case that the signal is corrupted by an additive white noise. The proposed method starts with mapping the noisy spectrum to a partial circulant matrix. In virtue of…

Data Analysis, Statistics and Probability · Physics 2020-10-29 X. C. Chen , Yu. A. Litvinov , M. Wang , Q. Wang , Y. H. Zhang

Estimation of the B-mode angular power spectrum of polarized anisotropies of the cosmic microwave background (CMB) is a key step towards a full exploitation of the scientific potential of this probe. In the context of pseudo-spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-05 A. Ferte , J. Grain , M. Tristram , R. Stompor

The topology and dynamics of the solar chromosphere are greatly affected by the presence of magnetic fields. The magnetic field can be inferred by analyzing polarimetric observations of spectral lines. Polarimetric signals induced by…

Solar and Stellar Astrophysics · Physics 2019-09-11 C. J. Díaz Baso , J. de la Cruz Rodríguez , S. Danilovic

In this paper we describe a self-contained method for performing the spectral-imaging deconvolution of X-ray data on clusters of galaxies observed by the ASCA satellite. Spatially-resolved spectral studies of data from this satellite…

Astrophysics · Physics 2009-10-31 D. A. White , D. Buote

We develop a formalism based on a time-dependent wave-function ansatz to study correlations of photons emitted from a collection of two-level quantum emitters. We show how to simulate the system dynamics and evaluate the intensity of the…

‹ Prev 1 8 9 10 Next ›