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Related papers: Dynamical Surface Imaging of lambda Andromedae

200 papers

[Abridged] We present a new deep 21-cm survey of the Andromeda galaxy, based on high resolution observations performed with the Synthesis Telescope and the 26-m antenna at DRAO. The HI distribution and kinematics of the disc are analyzed…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Laurent Chemin , Claude Carignan , Tyler Foster

We present interferometric angular sizes for 12 stars with known planetary companions, for comparison with 28 additional main-sequence stars not known to host planets. For all objects we estimate bolometric fluxes and reddenings through…

Solar and Stellar Astrophysics · Physics 2011-02-11 Gerard T. van Belle , Kaspar von Braun

Diffuse envelopes around Mira variables are among the most important sources influencing the chemical evolution of galaxies. However they represent an observational challenge because of their complex spectral features and their rapid…

Solar and Stellar Astrophysics · Physics 2009-11-13 Jean-Baptiste Le Bouquin , Sylvestre Lacour , Stephanie Renard , Eric Thiebaut , Antoine Merand , Tijl Verhoelst

We use data from the ARGO cosmic microwave background (CMB) anisotropy experiment to constrain cosmogonies. We account for the ARGO beamwidth and calibration uncertainties, and marginalize over the offset removed from the data. Our derived…

Model stellar atmospheres are fundamental tools for understanding stellar observations from interferometry, microlensing, eclipsing binaries and planetary transits. However, the calculations also include assumptions, such as the geometry of…

Solar and Stellar Astrophysics · Physics 2015-06-15 Hilding R. Neilson , John B. Lester

e present 4 very low mass stars radii measured with the VLTI using the 2.2 microns VINCI test instrument. The observations were carried out during the commissioning of the 104-meter-baseline with two 8-meter-telescopes. We measure angular…

Astrophysics · Physics 2009-11-07 D. Segransan , P. Kervella , T. Forveille , D. Queloz

The parameters of cosmological model with cold dark matter and cosmological constant (Lambda CDM) have been determined on a basis of three-year cosmic microwave background observations by space mission WMAP, as well as the data on the…

Astrophysics · Physics 2009-06-23 S. Apunevych , B. Venhlovska , Yu. Kulinich , B. Novosyadlyj

In this study, a W Ursae Majoris (W UMa) type system LO Andromedae (LO And) was observed over nine nights at Durham to fully investigate its physical properties and update its stellar parameters. After obtaining the observational data in…

Solar and Stellar Astrophysics · Physics 2024-12-03 Peifeng Peng

Using the Planetary Nebula Spectrograph, we have observed and measured the velocities for some 2764 PNe in the disk and halo of the Andromeda galaxy. Preliminary analysis using a basic ring model shows a rotation curve in good agreement…

We present novel observations utilising the Cassini spacecraft to conduct an observing campaign for stellar astronomy from a vantage point in the outer solar system. By exploiting occultation events in which Mira passed behind the Saturnian…

Instrumentation and Methods for Astrophysics · Physics 2013-06-24 Paul N. Stewart , Peter G. Tuthill , Matthew M. Hedman , Philip D. Nicholson , James P. Lloyd

We present HST/ACS observations of RR Lyrae variable stars in six ultra deep fields of the Andromeda galaxy (M31), including parts of the halo, disk, and giant stellar stream. Past work on the RR Lyrae stars in M31 has focused on various…

We have used Suprime-Cam on the Subaru Telescope to conduct a V- and I-band imaging survey of fields sampling the spheroid of the Andromeda galaxy along its south-east minor axis. Our photometric data are deep enough to resolve stars down…

Astrophysics · Physics 2007-05-23 Mikito Tanaka , Masashi Chiba , Yutaka Komiyama , Masanori Iye , Puragra Guhathakurta

The dynamics and thermal structure of the surface layers of stars with outer convection zones can be studied in some detail by means of numerical simulations of time-dependent compressible convection. In an effort to investigate the…

Astrophysics · Physics 2007-05-23 Matthias Steffen

We have executed a survey of nearby, main sequence A, F, and G-type stars with the CHARA Array, successfully measuring the angular diameters of fortyfour stars with an average precision of ~ 1.5%. We present new measures of the bolometric…

We analyse interferometric data obtained for Regulus with AMBER (Astronomical Multi- BEam combineR) at high spectral resolution ($\lambda/\delta\lambda \approx 12000$) across the Br$\gamma$ spectral line. The study of the photocentre…

Solar and Stellar Astrophysics · Physics 2018-08-07 M. Hadjara , R. G. Petrov , S. Jankov , P. Cruzalèbes , A. Spang , S. Lagarde

We present K-band observations of five Mira stars with the IOTA interferometer. The interferograms were obtained with the FLUOR fiber optics beam combiner which provides high-accuracy visibility measurements in spite of time-variable…

We have developed a three-dimensional radiation hydrodynamics code to simulate the interaction of convection and radial pulsation in classical variable stars. One key goal is the ability to carry these simulations to full amplitude in order…

Solar and Stellar Astrophysics · Physics 2015-06-16 Chris M. Geroux , Robert G. Deupree

Context. The surface structures and dynamics of cool stars are characterized by the presence of convective motions and turbulent flows which shape the emergent spectrum. Aims. We used realistic three-dimensional radiative hydrodynamical…

Solar and Stellar Astrophysics · Physics 2018-03-14 A. Chiavassa , L. Casagrande , R. Collet , Z. Magic , L. Bigot , F. Thevenin , M. Asplund

We present new interferometer molecular observations of R Leo taken at 1.2 mm with the Atacama Large Millimeter Array with an angular resolution up to ~0.026 arcsec. These observations permit us to resolve the innermost envelope of this…

Solar and Stellar Astrophysics · Physics 2019-02-20 J. P. Fonfría , M. Santander-García , J. Cernicharo , L. Velilla-Prieto , M. Agúndez , N. Marcelino , G. Quintana-Lacaci

We developed an Inverse Photometric method (IPM) to determine global physical parameters of RR Lyrae stars exclusively from multicolor light curves (S\'odor, Jurcsik & Szeidl, 2009, MNRAS, 394, 261). We showed that for good quality…

Solar and Stellar Astrophysics · Physics 2010-04-13 Á. Sódor