English
Related papers

Related papers: A Frequency Comb calibrated Solar Atlas

200 papers

In this paper, we investigate the relationship between 150MHz luminosity and star formation rate (the SFR-L150 relation) using 150MHz measurements for a near-infrared selected sample of 118,517 $z<1$ galaxies. New radio survey data offer…

Wavefront stabilization is a fundamental challenge to high contrast imaging of exoplanets. For both space and ground observations, wavefront control performance is ultimately limited by the finite amount of starlight available for sensing,…

Instrumentation and Methods for Astrophysics · Physics 2017-06-23 Olivier Guyon , Kelsey Miller , Jared Males , Ruslan Belikov , Brian Kern

The Low Frequency Array (LOFAR) is the only existing radio interferometer able to observe at ultra-low frequencies (<100 MHz) with high resolution (<15") and high sensitivity (<1 mJy/beam). To exploit these capabilities, the LOFAR Surveys…

The measurement of Doppler velocities in spectroscopic solar observations requires a reference for the local frame of rest. The rotational and radial velocities of the Earth and the rotation of the Sun introduce velocity offsets in the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Jaime de la Cruz Rodríguez , Dan Kiselman , Mats Carlsson

A large spectroscopic survey is constructed of galaxies in the Coma cluster. The survey covers a wide area (1 deg$^2$) to deep magnitudes (R ~ 19.5), covering both the core (high density) and outskirts (intermediate to low density) of the…

Slightly underdoped high-Tc system La(1.86)Sr(0.14)CuO(4) (LSCO) is studied by means of high energy high resolution angular resolved photoemission spectroscopy (ARPES) and combined computational scheme LDA+DMFT+Sk. Corresponding one band…

Strongly Correlated Electrons · Physics 2010-09-28 I. A. Nekrasov , E. E. Kokorina , E. Z. Kuchinskii , M. V. Sadovskii , S. Kasai , A. Sekiyama , S. Suga

Transmission spectroscopy has greatly advanced the study of exoplanet atmospheres, but stellar surface heterogeneities can contaminate transit spectra. Characterising how stellar spectra vary across the stellar disc is therefore essential…

Solar and Stellar Astrophysics · Physics 2026-04-29 E. C. Gonçalves , E. Cristo , W. Dethier , N. C. Santos , S. G. Sousa , P. T. P. Viana , T. Azevedo Silva , R. Allart , V. Bourrier

We have carried out dual-comb spectroscopy and observed in a simultaneous acquisition a 140-THz-wide spectrum from 1.0 to 1.9 {\mu}m using two fiber-based frequency combs phase-locked to each other. This ultra-broad wavelength bandwidth is…

Bisectors of the HARPS cross-correlation function (CCF) can discern between planetary radial-velocity (RV) signals and spurious RV signals from stellar magnetic activity variations. However, little is known about the effects of the stellar…

Solar and Stellar Astrophysics · Physics 2011-10-06 O. Basturk , T. H. Dall , R. Collet , G. Lo Curto , S. O. Selam

We present the design concept of the wavelength calibration system for the Habitable-zone Planet Finder instrument (HPF), a precision radial velocity (RV) spectrograph designed to detect terrestrial-mass planets around M-dwarfs. HPF is a…

Instrumentation and Methods for Astrophysics · Physics 2014-08-19 Samuel Halverson , Suvrath Mahadevan , Lawrence Ramsey , Ryan Terrien , Arpita Roy , Christian Schwab , Chad Bender , Fred Hearty , Eric Levi , Steve Osterman , Gabe Ycas , Scott Diddams

Optical frequency combs are increasingly used in applications such as optical communications, radio signal processing, and dual-comb spectroscopy. Many of these applications require a broad, flat spectrum with tunable center wavelength and…

Optics · Physics 2025-05-06 Yijia Cai , Zhixin Liu

Aims. We present a new list of thorium and argon emission lines in the visible obtained by analyzing high-resolution (R=110,000) spectra of a ThAr hollow cathode lamp. The aim of this new line list is to allow significant improvements in…

Astrophysics · Physics 2009-11-13 C. Lovis , F. Pepe

LOFAR is a new and sensitive radio interferometer that can be used for dynamic high-resolution imaging spectroscopy at low radio frequencies from 10 to 90 and 110 to 250 MHz. Here we describe its usage for observations of the Sun and in…

Instrumentation and Methods for Astrophysics · Physics 2016-03-22 Frank Breitling , Gottfried Mann , Christian Vocks , Matthias Steinmetz , Klaus G. Strassmeier

The performance of adaptive optics systems employing sodium laser guide stars can be improved by continuously monitoring the vertical density structure of mesospheric sodium along the line of sight. We demonstrate that sodium density…

Instrumentation and Methods for Astrophysics · Physics 2020-04-01 Joschua A. Hellemeier , Domenico Bonaccini Calia , Paul Hickson , Angel Otarola , Thomas Pfrommer

The latest generation of high-resolution spectrograph instruments on 10m-class telescopes continue to pursue challenging science cases. Consequently, ever more precise calibration methods are necessary to enable trail-blazing science…

We present parameterized broadband spectral models valid at frequencies between 30-300 MHz for six bright radio sources selected from the 3C survey, spread in Right Ascension from 0-24 hours. For each source, data from the literature are…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Anna M. M. Scaife , George H. Heald

Quantitative helio- and asteroseismology require very precise measurements of the frequencies, amplitudes, and lifetimes of the global modes of stellar oscillation. It is common knowledge that the precision of these measurements depends on…

Astrophysics · Physics 2009-11-13 Thorsten Stahn , Laurent Gizon

A fieldable dual-comb spectrometer is described based on a "bootstrapped" frequency referencing scheme in which short-term optical phase coherence between combs is attained by referencing each to a free-running diode laser, whilst high…

We present a detailed analysis of a very high resolution (R\approx 112,000) spectrum of the quasar HE 0515-4414 obtained using the High Accuracy Radial velocity Planet Searcher (HARPS) mounted on the ESO 3.6 m telescope at the La Silla…

At Pic du Midi observatory we carry out a solar survey with images of the photosphere, prominences and corona. This survey, named CLIMSO (CLIch\'es Multiples du SOleil), is in the following spectral lines: Fe XIII corona (1.075 micron),…

Instrumentation and Methods for Astrophysics · Physics 2019-10-23 Laurent Koechlin , Luc Dettwiller , Maurice Audejean , Mael Valais , Arturo Lopez Ariste
‹ Prev 1 3 4 5 6 7 10 Next ›