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Related papers: A Frequency Comb calibrated Solar Atlas

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Laser frequency combs (LFCs) are well on their way to becoming the next-generation calibration sources for precision astronomical spectroscopy. This development is considered key in the hunt for low-mass rocky exoplanets around solar-type…

The advent of the laser frequency comb as the wavelength calibration unit allows us to measure the radial velocity at $cm\ s^{-1}$ precision level with high stability in long-term, which enable the possibility of the detection of…

Instrumentation and Methods for Astrophysics · Physics 2018-10-15 Zhao Fei , Zhao Gang , Liu Yujuan , Wang Liang , Wang Huijuan , Li Hongbin , Ye Huiqi , Hao Zhibo , Xiao Dong , Zhang Junbo , Kellermann Hanna , Grupp Frank

Laser frequency combs (LFCs) are an important component of Doppler radial velocity (RV) spectroscopy that pushes fractional precision to the $10^{-10}$ level, as required to identify and characterize Earth-like exoplanets. However, large…

Instrumentation and Methods for Astrophysics · Physics 2025-02-11 Pooja Sekhar , Connor Fredrick , Peter Zhong , Abijith S Kowligy , Arman Cingöz , Scott A Diddams

Aims. We study the 2D spectral line profile of HARPS (High Accuracy Radial Velocity Planet Searcher), measuring its variation with position across the detector and with changing line intensity. The characterization of the line profile and…

We investigate a new scheme for astronomical spectrograph calibration using the laser frequency comb at the Solar Vacuum Tower Telescope on Tenerife. Our concept is based upon a single-mode fiber channel, that simultaneously feeds the…

Instrumentation and Methods for Astrophysics · Physics 2015-02-18 R A Probst , L Wang , H-P Doerr , T Steinmetz , T J Kentischer , G Zhao , T W Hänsch , Th Udem , R Holzwarth , W Schmidt

Using a turn-key Ti:sapphire femtosecond laser frequency comb, an off-the-shelf supercontinuum device, and Fabry-Perot mode filters, we report the generation of a 16 GHz frequency comb spanning a 90 nm band about a center wavelength of 566…

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such as atomic clocks. Such `frequency combs'…

A wavelength calibration system based on a laser frequency comb (LFC) was developed in a co-operation between the Kiepenheuer-Institut f\"ur Sonnenphysik, Freiburg, Germany and the Max-Planck-Institut f\"ur Quantenoptik, Garching, Germany…

Instrumentation and Methods for Astrophysics · Physics 2012-04-05 H. -P. Doerr , T. Steinmetz , R. Holzwarth , T. Kentischer und W. Schmidt

Laser frequency combs (LFCs) are a promising technology for wavelength calibration of astronomical high-resolution spectrographs requiring utmost accuracy and stability, since they directly translate the fundamental SI time standard from…

Astronomical spectrographs require frequency calibration through sources like hollow-cathode lamps or absorption-gas cells. Laser frequency combs (LFCs) provide highest accuracy but are facing operational challenges. We aim to provide a…

Instrumentation and Methods for Astrophysics · Physics 2024-09-05 Ansgar Reiners , Michael Debus , Sebastian Schäfer , Eberhard Tiemann , Mathias Zechmeister

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require measurements of Doppler velocity drifts of about 1…

Precise astronomical spectroscopic analyses routinely assume that individual pixels in charge-coupled devices (CCDs) have uniform sensitivity to photons. Intra-pixel sensitivity (IPS) variations may already cause small systematic errors in,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Michael T. Murphy , Clayton R. Locke , Philip S. Light , Andre N. Luiten , Jon S. Lawrence

Searches for extrasolar planets using the periodic Doppler shift of stellar spectral lines have recently achieved a precision of 60 cm/s (ref 1), which is sufficient to find a 5-Earth-mass planet in a Mercury-like orbit around a Sun-like…

We describe and characterize a 25 GHz laser frequency comb based on a cavity-filtered erbium fiber mode-locked laser. The comb provides a uniform array of optical frequencies spanning 1450 nm to 1700 nm, and is stabilized by use of a global…

Disk-integrated observations of the Sun provide a unique vantage point to explore stellar activity and its effect on measured radial velocities. Here, we report a new approach for disk-integrated solar spectroscopy and evaluate its…

The search for earth-like exoplanets with the Doppler radial velocity technique is an extremely challenging and multifaceted precision spectroscopy problem. Currently, one of the limiting instrumental factors in reaching the required…

Doppler spectroscopy has uncovered or confirmed all the known planets orbiting nearby stars. Two main techniques are used to obtain precision Doppler measurements at optical wavelengths. The first approach is the gas cell method, which…

Earth and Planetary Astrophysics · Physics 2015-06-04 Guillem Anglada-Escudé , R. Paul Butler

The Sun's spectrum varies with center-to-limb distance. This variation is governed by the underlying temperature-density structure of the solar atmosphere. To explore the spectrally resolved center-to-limb variation (CLV) we make use of two…

Solar and Stellar Astrophysics · Physics 2014-12-24 Jan Stenflo

Precision laser spectroscopy is key to many developments in atomic and molecular physics and the advancement of related technologies such as atomic clocks and sensors. However, in important spectroscopic scenarios, such as astronomy and…

Typical astronomical spectrographs have a resolution ranging between a few hundred to 200.000. Deconvolution and correlation techniques are being employed with a significance down to 1/1000 th of a pixel. HeAr and ThAr lamps are usually…

Astrophysics · Physics 2015-05-13 Piet O. Schmidt , Stefan Kimeswenger , Hans Ulrich Kaeufl
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