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Related papers: The limb-darkened Arcturus; Imaging with the IOTA/…

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A 13x13 degree image of Balmer H-alpha emission at galactic latitude -65 degrees is presented. Sensitivity is limited in part by confusion: the peak-to-valley anisotropy of the H-alpha surface brightness is 0.2 Rayleighs on angular scales…

Astrophysics · Physics 2009-10-30 Peter R. McCullough

We propose a method for measuring the temperature of fermionic atoms in an optical lattice potential from the intensity of the scattered light in the far-field diffraction pattern. We consider a single-component gas in a tightly-confined…

Quantum Gases · Physics 2009-10-24 J. Ruostekoski , C. J. Foot , A. B. Deb

Long-baseline interferometry at optical and near-infrared wavelengths is an emerging technology which is quickly becoming a useful tool to investigate stellar atmospheres and to compare observations with models. Stellar atmosphere models…

Astrophysics · Physics 2007-05-23 Markus Wittkowski

Asgard/NOTT (previously Hi-5) is a European Research Council (ERC)-funded project hosted at KU Leuven and a new visitor instrument for the Very Large Telescope Interferometer (VLTI). Its primary goal is to image the snow line region around…

We present a three dimensional hot Jupiter model, extending from 200 bar to 1 mbar, using the Intermediate General Circulation Model from the University of Reading. Our horizontal spectral resolution is T31 (equivalent to a grid of 48x96),…

Earth and Planetary Astrophysics · Physics 2015-05-13 Emily Rauscher , Kristen Menou

Benchmark stars with known angular diameters are key to calibrating interferometric observations. With the advent of optical interferometry, there is a need for suitably bright, well-vetted calibrator stars over a large portion of the sky.…

Solar and Stellar Astrophysics · Physics 2017-06-20 Samuel J. Swihart , E. Victor Garcia , Keivan G. Stassun , Gerard van Belle , Matthew W. Mutterspaugh , Nicholas Elias

In order to perform high resolution astrometry of the solar diameter from the ground, through the observations of eclipses, the study of the limb darkening profile is described. Knowing the profile of the solar limb is useful both to…

Solar and Stellar Astrophysics · Physics 2015-06-03 Andrea Raponi , Costantino Sigismondi , Konrad Guhl , Richard Nugent , Andreas Tegtmeier

Dense high-precision photometry of microlensed stars during a fold-caustic passage can be used to reveal their intensity profiles from which the temperature of the stellar atmosphere as function of fractional radius can be derived. While…

Astrophysics · Physics 2009-11-10 M. Dominik

We introduce a novel technique using closure amplitudes, inspired by radio interferometry, to determine with high angular resolution the two-dimensional profile of a light beam using an interferogram from a non-redundantly masked aperture.…

We have built and operated an atom interferometer of the Mach-Zehnder type. The atomic wave is a supersonic beam of lithium seeded in argon and the mirrors and beam-splitters for the atomic wave are based on elastic Bragg diffraction on…

Quantum Physics · Physics 2016-08-16 Alain Miffre , Marion Jacquey , Matthias Büchner , Gérard Trenec , Jacques Vigue

Photometric maps, obtained with Spitzer's Infrared Array Camera (IRAC), can provide a valuable probe of warm molecular hydrogen within the interstellar medium. IRAC maps of the supernova remnant IC443, extracted from the Spitzer archive,…

Astrophysics · Physics 2009-11-13 David Neufeld , Yuan Yuan

We are conducting a study on the imprint of the ISM on optical spectra based on two types of ongoing spectroscopic massive-star surveys: on the one hand, intermediate-resolution (R = 2500) green-blue spectra for ~3000 stars obtained with…

Astrophysics of Galaxies · Physics 2012-10-09 M Penadés Ordaz , J. Maíz Apellániz , A. Sota

A long-held vision has been to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, and reveal interacting gas flows in binary systems. An…

Instrumentation and Methods for Astrophysics · Physics 2015-08-12 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

Optical interferometers increasingly use single-mode fibers as spatial filters to convert varying wavefront distortion into intensity fluctuations which can be monitored for accurate calibration of fringe amplitudes. Here I propose using an…

Astrophysics · Physics 2009-11-06 J. D. Monnier

We present results from a spectro-interferometric study of the Miras o Cet, R Leo and W Hya obtained with the Keck Aperture Masking Experiment from 1998 Sep to 2002 Jul. The spectrally dispersed visibility data permit fitting with…

The disk of FU Orionis is marginally resolved with MATISSE, suggesting that the region emitting in the thermal infrared is rather compact. An upper limit of $\sim1.3\pm0.1$ mas (in $L$) can be given for the diameter of the disk region…

The study of protoplanetary disks, where the planets are believed to form, will certainly allow the formation of our Solar System to be understood. To conduct observations of these objects at the milli-arcsecond scale, infrared…

Astrophysics · Physics 2009-11-13 S. Renard , F. Malbet , E. Thiebaut , J. -P. Berger

The redshifted 21 cm brightness distribution from neutral hydrogen is a promising probe into the cosmic dark ages, cosmic dawn, and re-ionization. LOFAR's Low Band Antennas (LBA) may be used in the frequency range 45 MHz to 85 MHz (30>z>16)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 H. K. Vedantham , L. V. E. Koopmans , A. G. de Bruyn , S. J. Wijnholds , B. Ciardi , M. A. Brentjens

Differential Interferometry allows to obtain the differential visibility and phase, in addition to the spectrum. The differential phase contains important information about the structure and motion of stellar photosphere such as stellar…

We report on observations of the extended environment of the bright Be star $\gamma$-Cas performed using intensity interferometry measurements within its H$\alpha$ emission line. These observations were performed using a modified version of…

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