English
Related papers

Related papers: A six-apertures discrete beam combiners for J-band…

200 papers

Infrared interferometry is currently in a rapid development phase, with new instrumentation soon achieving milliarcsecond spatial resolutions for faint sources and astrometry on the order of 10 microarcseconds. For jet studies in…

Astrophysics · Physics 2009-06-25 Sera Markoff

A device based on a three-block Fresnel zone plate interferometer is proposed for hard X-ray phase-contrast imaging. The device combines a low requirement for the coherence of the initial radiation (the interferometer operates in the…

Instrumentation and Detectors · Physics 2021-04-22 L. A. Haroutunyan

Energy consumption and hardware cost of signal digitization together with the management of the resulting data volume form serious issues for high-rate measurement systems with multiple sensors. Switching to binary sensing front-ends…

Instrumentation and Methods for Astrophysics · Physics 2019-07-16 Manuel S. Stein

Hot exozodiacal dust emission was detected in recent surveys around two dozen main sequence stars at distances of less than $1\,\text{au}$ using H and K band interferometry. Due to the high contrast as well as the small angular distance…

Solar and Stellar Astrophysics · Physics 2017-11-15 Florian Kirchschlager , Sebastian Wolf , Robert Brunngräber , Alexis Matter , Alexander V. Krivov , Aaron Labdon

A multi-chord fiber-coupled interferometer [Merritt et al., Rev. Sci. Instrum. 83, 033506 (2012)] is being used to make time-resolved density measurements of supersonic argon plasma jets on the Plasma Liner Experiment [Hsu et al., Bull.…

In this contribution, we review the results of the ALSI project (Advanced Laser-writing for Stellar Interferometry), aimed at assessing the potential of ultrafast laser writing to fabricate mid-infared integrated optics (IO) devices with…

Instrumentation and Methods for Astrophysics · Physics 2020-03-06 L. Labadie , S. Minardi , J. Tepper , R. Diener , B. Muthusubramanian , J. -U. Pott , S. Nolte , S. Gross , A. Arriola , M. J. Withford

This paper presents a non-zoned discrete dielectric lens comprising two or three matching layers to reduce the 50-110 GHz frequency range reflections. Based on Chebyshev and binomial multi-section transformers, the designed models use…

Signal Processing · Electrical Eng. & Systems 2023-11-27 Juan Andrés Vásquez-Peralvo , José Manuel Fernández-González , Thomas Wong

We report on the fabrication and characterization of composite multimode waveguide structures that consist of a stack of single-mode waveguides fabricated by ultrafast laser inscription. We explore 2 types of composite structures; those…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Nemanja Jovanovic , Izabela Spaleniak , Simon Gross , Michael Ireland , Jon S. Lawrence , Christopher Miese , Alexander Fuerbach , Michael J. Withford

There are numerous advantages to exploiting diffraction-limited instrumentation at astronomical observatories, which include smaller footprints, less mechanical and thermal instabilities and high levels of performance. To realize such…

Instrumentation and Methods for Astrophysics · Physics 2013-11-05 Izabela Spaleniak , Nemanja Jovanovic , Simon Gross , Michael J. Ireland , Jon S. Lawrence , Michael J. Withford

Multi-wavelength imaging polarimetry at far-infrared wavelengths has proven to be an excellent tool for studying the physical properties of dust, molecular clouds, and magnetic fields in the interstellar medium. Although these wavelengths…

Improved quantum sensing of photons from astronomical objects could provide high resolution observations in the optical benefiting numerous fields, including general relativity, dark matter studies, and cosmology. It has been recently…

Instrumentation and Methods for Astrophysics · Physics 2022-11-03 Paul Stankus , Andrei Nomerotski , Anže Slosar , Stephen Vintskevich

Stellar amplitude interferometry is limited by the need to have optical distances fixed and known to a fraction of the wavelength. We suggest reviving intensity interferometry, which requires hardware which is many orders of magnitude less…

Astrophysics · Physics 2009-11-11 Aviv Ofir , Erez N. Ribak

We present observations of the T Tauri stars BP Tau, DG Tau, DI Tau, GM Aur, LkCa 15, RW Aur and V830 Tau, using long baseline infrared interferometry at K band (2.2 microns) from the Keck Interferometer. The target sources have a range of…

Photonic integration offers the potential to bring complex high-performance optical systems to the form factor of a compact semiconductor chip. However, the range of system functions accessible critically depends on the extent to which…

Diffuse interstellar bands (DIBs) hold a lot of information about the state and the structure of the ISM. Structure can most directly be observed by extensive spectroscopic surveys, including surveys of stars where DIBs are especially…

Astrophysics of Galaxies · Physics 2017-05-10 Janez Kos

Discovered almost a century ago, the Diffuse Interstellar Bands (DIBs) still lack convincing and comprehensive identification. Hundreds of DIBs have now been observed in the near-ultraviolet (NUV), visible and near-infrared (NIR). They are…

Astrophysics of Galaxies · Physics 2019-03-20 M. G. Rawlings , A. J. Adamson , C. C. M. Marshall , P. J. Sarre

We report the first use of Michelson interferometry on the Keck I telescope for diffraction-limited imaging in the near infrared JHK and L bands. By using an aperture mask located close to the f/25 secondary, the 10 m Keck primary mirror…

Astrophysics · Physics 2009-10-31 P. G. Tuthill , J. D. Monnier , W. C. Danchi , E. H. Wishnow , C. A. Haniff

Echelle spectra of the double-lined spectroscopic binary HD 204827 were obtained on five nights, at a resolving power R = 38,000 and with a S/N ratio = 750 near 6000 A in the final, combined spectrum. The stars show E(B-V) = 1.11 and…

Microcombs - optical frequency combs generated in microresonators - have advanced tremendously in the last decade, and are advantageous for applications in frequency metrology, navigation, spectroscopy, telecommunications, and microwave…

Radial velocity (RV) surveys supported by high precision wavelength references (notably ThAr lamps and I2 cells) have successfully identified hundreds of exoplanets; however, as the search for exoplanets moves to cooler, lower mass stars,…

‹ Prev 1 4 5 6 7 8 10 Next ›