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Related papers: A New Method of Deriving Doppler Velocities for So…

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We present a new method of removing PSF artifacts and improving the resolution of multidimensional data sources including imagers and spectrographs. Rather than deconvolution, which is translationally invariant, this method is based on…

NASA's Solar Dynamics Observatory is delivering vector field observations of the full solar disk with unprecedented temporal and spatial resolution; however, the satellite is in a highly inclined geostationary orbit. The relative…

Solar and Stellar Astrophysics · Physics 2016-06-01 P. W. Schuck , Spiro Antiochos , K. D. Leka , Graham Barnes

Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity measurements, which limit efforts to discover and measure…

Common signal-processing approximations produce artefacts when timing pulsars in relativistic binary systems, especially edge-on systems with tight orbits, such as the Double Pulsar. In this paper, we use extensive simulations to explore…

High Energy Astrophysical Phenomena · Physics 2025-02-19 Huanchen Hu , Nataliya K. Porayko , Willem van Straten , Michael Kramer , David J. Champion , Michael J. Keith

The measurement of Doppler velocity shifts in spectra is a ubiquitous theme in astronomy, usually handled by computing the cross-correlation of the signals, and finding the location of its maximum. This paper addresses the problem of the…

Astrophysics · Physics 2008-11-26 Carlos Allende Prieto

The zero point of measured photospheric Doppler shifts is uncertain for at least two reasons: instrumental variations (from, e.g., thermal drifts), and the convective blueshift, a known correlation between intensity and upflows. Calibrated…

Solar and Stellar Astrophysics · Physics 2015-06-03 Brian T. Welsch , George H. Fisher , Xudong Sun

The derivation of radial velocities from large numbers of spectra that typically result from survey work, requires automation. However, except for the classical cases of slowly rotating late-type spectra, existing methods of measuring…

Instrumentation and Methods for Astrophysics · Physics 2014-05-20 M. David , R. Blomme , Y. Frémat , Y. Damerdji , C. Delle Luche , E. Gosset , D. Katz , Y. Viala

When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. van Noort

Imaging systems based on a narrow-band tunable filter are used to obtain Doppler velocity maps of solar features. These velocity maps are created by taking the difference between the blue- and red-wing intensity images of a chosen spectral…

Solar and Stellar Astrophysics · Physics 2010-09-16 Sreejith Padinhatteeri , R. Sridharan , K. Sankarasubramanian

context: The combination of image restoration and a Fabry-P\'{e}rot interferometer (FPI) based instrument in solar observations results in specific calibration issues. FPIs generally show variations over the field-of-view, while in the…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. S. Schnerr , J. de la Cruz Rodriguez , M. van Noort

Some pulsating stars are good clocks. When they are found in binary stars, the frequencies of their luminosity variations are modulated by the Doppler effect caused by orbital motion. For each pulsation frequency this manifests itself as a…

Solar and Stellar Astrophysics · Physics 2015-06-04 Hiromoto Shibahashi , Donald W. Kurtz

Doppler orbitography uses the Doppler shift in a transmitted signal to determine the orbital parameters of satellites including range and range-rate (or radial velocity). We describe two techniques for atmospheric-limited optical Doppler…

Instrumentation and Methods for Astrophysics · Physics 2020-06-09 Benjamin P. Dix-Matthews , Sascha W. Schediwy , David R. Gozzard , Simon Driver , Karl Ulrich Schreibe , Randall Carman , Michael Tobar

The Solar Orbiter mission, with an orbit outside the Sun Earth line and leaving the ecliptic plane, opens up opportunities for the combined analysis of measurements obtained by solar imagers and spectrometers. For the first time, different…

Solar and Stellar Astrophysics · Physics 2021-11-24 O. Podladchikova , L. Harra , K. Barczynski , C. H. Mandrini , F. Auchere , D. Berghmans , E. Buchlin , L. Dolla , M. Mierla , S. Parenti , L. Rodriguez

We present new periodograms that are effective in distinguishing Doppler shift from spectral shape variability in astronomical spectra. These periodograms, building upon the concept of partial distance correlation, separate the periodic…

Instrumentation and Methods for Astrophysics · Physics 2022-04-06 Avraham Binnenfeld , Sahar Shahaf , Richard I. Anderson , Shay Zucker

Cross-correlation of consecutive Doppler images is one of the most common techniques used to detect surface differential rotation (hereafter DR) on spotted stars. The disadvantage of a single cross-correlation is, however, that the expected…

Solar and Stellar Astrophysics · Physics 2015-06-17 Zsolt Kővári , János Bartus , Levente Kriskovics , Krisztián Vida , Katalin Oláh

Access to knowledge of the point spread function (PSF) of adaptive optics(AO)-assisted observations is still a major limitation when processing AO data. This limitation is particularly important when image analysis requires the use of…

Instrumentation and Methods for Astrophysics · Physics 2023-05-10 A. Lau , R. JL. Fétick , B. Neichel , O. Beltramo-Martin , T. Fusco

We present a new technique based on fixed-delay interferometry for high throughput, high precision and multi-object Doppler radial velocity (RV) surveys for extra-solar planets. The Doppler measurements are conducted through monitoring the…

Astrophysics · Physics 2016-08-30 Jian Ge

We provide formulae for the calculation of precise Doppler velocities of sunlight, in both the case of direct observations of the Sun and in reflection from the surfaces of solar system objects such as the Moon or asteroids. We discuss the…

Earth and Planetary Astrophysics · Physics 2020-08-17 Jason T. Wright , Shubham Kanodia

The precise radial velocity technique is a cornerstone of exoplanetary astronomy. Astronomers measure Doppler shifts in the star's spectral features, which track the line-of/sight gravitational accelerations of a star caused by the planets…

Earth and Planetary Astrophysics · Physics 2019-02-06 Jason T. Wright

The Doppler effect of light was implemented by interference with a reference wave to infer linear velocities in early manifestations, and more recently lateral and angular velocities with scalar phase structured light. A consequence of the…

Optics · Physics 2019-12-10 Liang Fang , Zhenyu Wan , Andrew Forbes , Jian Wang
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