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Related papers: An Error Analysis of the Geometric Baade-Wesselink…

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The projection factor (p), which converts the radial velocity to pulsational velocity, is an important parameter in the Baade-Wesselink (BW) type analysis and distance scale work. The p-factor is either adopted as a constant or linearly…

Solar and Stellar Astrophysics · Physics 2015-06-05 Chow-Choong Ngeow , Hilding R. Neilson , Nicolas Nardetto , Massimo Marengo

The inference of stellar parameters (such as radius and mass) through asteroseismic forward modelling depends on the number, accuracy, and precision of seismic and atmospheric constraints. ESA's Gaia space mission is providing precise…

Solar and Stellar Astrophysics · Physics 2024-12-09 Benard Nsamba , Achim Weiss , Juma Kamulali

Interferometric methods have been recently investigated to achieve sub-Rayleigh imaging and precision measurements of faint incoherent sources up to the ultimate quantum limit. Here we consider single-photon imaging of two point-like…

Quantum Physics · Physics 2024-02-28 Luigi Santamaria Amato , Fabrizio Sgobba , Cosmo Lupo

Baseline calibration of a stellar interferometer is a prerequisite to data reduction of astrometric operations. This technique of astrometry is triangulation of star positions. Since angles are deduced from the baseline and delay side of…

Instrumentation and Methods for Astrophysics · Physics 2009-06-16 Richard J. Mathar

In this paper, we analyze the error estimate of a wavelet frame based image restoration method from degraded and incomplete measurements. We present the error between the underlying original discrete image and the approximate solution which…

Analysis of PDEs · Mathematics 2022-08-23 Jian-Feng Cai , Jae Kyu Choi , Jianbin Yang

The Chinese Space Station Telescope (CSST) spectroscopic survey aims to deliver high-quality low-resolution ($R > 200$) slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag, distributed within a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-05 Haibo Yuan , Dingshan Deng , Yang Sun

Context. Limb darkening is an important tool for understanding stellar atmospheres, but most observations measuring limb darkening assume various parameterizations that yield no significant information about the structure of stellar…

Solar and Stellar Astrophysics · Physics 2015-06-05 Hilding R. Neilson , John B. Lester

We study nonparametric density estimation problems where error is measured in the Wasserstein distance, a metric on probability distributions popular in many areas of statistics and machine learning. We give the first minimax-optimal rates…

Statistics Theory · Mathematics 2020-04-30 Jonathan Niles-Weed , Quentin Berthet

Here we present a Bayesian method of including discrete measurements of dispersion measure due to the interstellar medium in the direction of a pulsar as prior information in the analysis of that pulsar. We use a simple simulation to show…

Instrumentation and Methods for Astrophysics · Physics 2013-12-10 Lindley Lentati , Paul Alexander , Michael P. Hobson

We explore the sensitivity of limb darkening coefficients computed from stellar atmosphere models to different least-squares fitting methods. We demonstrate that conventional methods are strongly biased to fitting the stellar limb. Our…

Astrophysics · Physics 2008-11-26 David Heyrovsky

Many machine learning problems can be seen as approximating a \textit{target} distribution using a \textit{particle} distribution by minimizing their statistical discrepancy. Wasserstein Gradient Flow can move particles along a path that…

Machine Learning · Statistics 2024-06-07 Song Liu , Jiahao Yu , Jack Simons , Mingxuan Yi , Mark Beaumont

We extend the Bayesian model fitting shape measurement method presented in Miller et al. (2007) and use the method to estimate the shear from the Shear TEsting Programme simulations (STEP). The method uses a fast model fitting algorithm…

Astrophysics · Physics 2009-11-13 T. D. Kitching , L. Miller , C. E. Heymans , L. van Waerbeke , A. F. Heavens

Galactic Cepheids are necessary tools for calibrating the period-luminosity relation, but distances to individual Galactic Cepheids are difficult to precisely measure and are limited to a small number of techniques such as direct parallax,…

Solar and Stellar Astrophysics · Physics 2015-06-11 Chow-Choong Ngeow , Hilding Neilson , Nicolas Nardetto , Massimo Marengo

The knowledge of receiver beam shapes is essential for accurate radio interferometric imaging. Traditionally, this information is obtained by holographic techniques or by numerical simulation. However, such methods are not feasible for an…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Sarod Yatawatta

We present a method, based on Bayesian statistics, to fit the dust emission parameters in the far-infrared and submillimeter wavelengths. The method estimates the dust temperature and spectral emissivity index, plus their relationship,…

Astrophysics of Galaxies · Physics 2015-06-15 M. Veneziani , F. Piacentini , A. Noriega-Crespo , S. Carey , R. Paladini , D. Paradis

We propose of an improved version of the ubiquitous symmetrization inequality making use of the Wasserstein distance between a measure and its reflection in order to quantify the symmetry of the given measure. An empirical bound on this…

Statistics Theory · Mathematics 2020-01-07 Adam B Kashlak

Uplink pre-compensation in ground-to-satellite optical links remains a problem, with an appropriate measurement of the wavefront error in the uplink path often not being available. We present a method that uses successive measurements of…

Instrumentation and Detectors · Physics 2025-09-12 Alex Frost , Nicolas Maron , Shane Walsh , Benjamin Dix-Matthews , Sascha Schediwy , Michael Hart

A limiting systematic effect in 21-cm interferometric experiments is the chromaticity due to the coupling between the sky and the instrument. This coupling is sourced by the instrument primary beam; therefore it is important to know the…

Instrumentation and Methods for Astrophysics · Physics 2022-06-22 Ainulnabilah Nasirudin , David Prelogovic , Steven G. Murray , Andrei Mesinger , Gianni Bernardi

In 21-cm experimental cosmology, accurate characterization of a radio telescope's antenna beam response is essential to measure the 21-cm signal. Computational electromagnetic (CEM) simulations estimate the antenna beam pattern and…

Instrumentation and Methods for Astrophysics · Physics 2024-08-30 Joshua J. Hibbard , Bang D. Nhan , David Rapetti , Jack O. Burns

We develop a robust technique to determine the minimum variability timescale for Gamma-ray Burst light curves, utilizing Haar wavelets. Our approach averages over the data for a given GRB, providing an aggregate measure of signal variation…

High Energy Astrophysical Phenomena · Physics 2015-06-19 V. Zach Golkhou , Nathaniel R. Butler
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