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Related papers: Infrared Excess in the Be Star Delta Scorpii

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We report high-precision observations of the linear polarization of the F1$\,$III star $\theta$ Scorpii. The polarization has a wavelength dependence of the form expected for a rapid rotator, but with an amplitude several times larger than…

Solar and Stellar Astrophysics · Physics 2022-04-20 Fiona Lewis , Jeremy Bailey , Daniel V. Cotton , Ian D. Howarth , Lucyna Kedziora-Chudczer , Floor van Leeuwen

Be/X-ray binaries are the most populous class of High Mass X-ray Binaries. Their X-ray duty cycle is tightly related to the optical companion wind activity, which in turn can be studied through optical spectroscopical dedicated…

Solar and Stellar Astrophysics · Physics 2017-07-05 C. Malacaria , W. Kollatschny , E. Whelan , A. Santangelo , D. Klochkov , V. McBride , L. Ducci

The gamma-ray binary LS I +61 303 is composed of a Be star and a compact companion orbiting in an eccentric orbit. Variable flux modulated with the orbital period of ~26.5 d has been detected from radio to very high-energy gamma rays. In…

High Energy Astrophysical Phenomena · Physics 2015-02-25 X. Paredes-Fortuny , M. Ribó , V. Bosch-Ramon , J. Casares , O. Fors , J. Núñez

In the last years, space missions such as COROT, Kepler or MOST have provided very accurate photometric observational data. In the particular case of $\delta$ Scuti stars, the observed frequency spectra have hundreds (if not thousands) of…

Solar and Stellar Astrophysics · Physics 2015-03-13 A. Moya , A. García Hernández , J. -C. Suárez , C. Rodríguez-López , R. Garrido

The Disk Detective project, a citizen science initiative, aims to identify circumstellar discs around stars by detecting objects with infrared (IR) excess using data from the Wide-field Infrared Survey Explorer (WISE). In this study, we…

(Abridged) We have completed the first systematic survey for disks around spectroscopically identified young brown dwarfs and very low mass stars. We have obtained L'-band (3.8 um) imaging for 38 very cool objects in IC 348 and Taurus. Our…

Astrophysics · Physics 2008-11-26 Michael C. Liu , Joan Najita , Alan T. Tokunaga

Excess infrared flux from white dwarf stars is likely to arise from a dusty debris disk or a cool companion. In this work, we present near-infrared spectroscopic observations with Keck/MOSFIRE, Gemini/GNIRS, and Gemini/Flamingos-2 of seven…

Solar and Stellar Astrophysics · Physics 2023-06-14 Dylan Owens , Siyi Xu , Elena Manjavacas , S. K. Leggett , S. L. Casewell , Erik Dennihy , Patrick Dufour , Beth L. Klein , Sherry Yeh , B. Zuckerman

Stellar infrared excesses can indicate various phenomena of interest, from protoplanetary disks to debris disks, or (more speculatively) techno-signatures along the lines of Dyson spheres. In this paper, we conduct a large search for such…

Earth and Planetary Astrophysics · Physics 2024-09-20 Gabriella Contardo , David W. Hogg

This study presents a search for IR excess in the 3.4, 4.6, 12 and 22 $\mu$m bands in a sample of 216 targets, composed of solar sibling, twin and analog stars observed by the \textit{WISE} mission. In general, an infrared excess suggests…

We have computed theoretical models of circumstellar disks for the classical Be stars $\kappa$ Dra, $\beta$ Psc, and $\upsilon$ Cyg. Models were constructed using a non-LTE radiative transfer code developed by \citet{sig07} which…

Astrophysics · Physics 2009-11-13 C. E. Jones , C. Tycner , T. A. A. Sigut , J. A. Benson , D. J. Hutter

We examine the mid-infrared fluxes and spectral energy distributions for metal-poor stars with iron abundances [Fe/H] $\lesssim-5$, as well as two CEMP-no stars, to eliminate the possibility that their low metallicities are related to the…

Solar and Stellar Astrophysics · Physics 2015-06-22 Kim A. Venn , Thomas H. Puzia , Mike Divell , Stephanie Cote , David L. Lambert , Else Starkenburg

High-precision interferometric observations of six early-type main sequence stars known to harbour cold debris discs have been obtained in the near-infrared K band with the FLUOR instrument at the CHARA Array. The measured squared…

The current knowledge of the abundance pattern in delta Scuti stars is based on the analysis of just a few field stars. We aim to determine the general chemical properties of the atmospheres of delta Scuti stars based on a statistically…

Astrophysics · Physics 2009-11-13 L. Fossati , K. Kolenberg , P. Reegen , W. Weiss

Intermediate dispersion spectroscopic observations of 37 Herbig Ae/Be stars reveal that the equivalent widths of their [OI] 6300A and Halpha emission lines, are related to their near-infrared colours in the same fashion as the T-Tauri…

Astrophysics · Physics 2007-05-23 Myles Corcoran , Thomas P. Ray

We present James Webb Space Telescope observations of the globular cluster NGC 6397 and use them to extend to infrared wavelengths the characterization of the cluster's entire white dwarf (WD) cooling sequence (CS). The data allows us to…

Solar and Stellar Astrophysics · Physics 2024-05-06 L. R. Bedin , D. Nardiello , M. Salaris , M. Libralato , P. Bergeron , A. J. Burgasser , D. Apai , M. Griggio , M. Scalco , J. Anderson , R. Gerasimov , A. Bellini

L-band data of 30 Doradus at 3.5 micron taken with SPIREX (South Pole Infrared Explorer) is presented. The photometry was combined with 2MASS JHK data at 1.25-2.2 micron. Colour-colour and colour-magnitude diagrams are constructed and used…

Astrophysics · Physics 2009-11-11 M. Maercker , M. G. Burton

The Herbig Ae/Be star LkHalpha 101 has been imaged at high angular resolution at a number of wavelengths in the near-infrared (from 1 to 3 microns) using the Keck 1 Telescope, and also observed in the mid-infrared (11.15 microns) using the…

Astrophysics · Physics 2009-11-07 P. G. Tuthill , J. D. Monnier , W. C. Danchi , D. D. S. Hale , C. H. Townes

The young open cluster NGC 6611 includes among its candidate members a class of peculiar objects with interesting properties: blue stars with infrared IR excesses. These stars show excesses in IR bands, signature of the presence of a…

Solar and Stellar Astrophysics · Physics 2015-06-16 R. Bonito , L. Prisinzano , M. G. Guarcello , G. Micela

We present the results of a high-resolution imaging survey of 12 brown dwarfs and very low mass stars in the closest (~145 pc) young (~5 Myr) OB association, Upper Scorpius. We obtained images with the Advanced Camera for Surveys/High…

Astrophysics · Physics 2009-11-13 A. L. Kraus , R. J. White , L. A. Hillenbrand

The rapidly rotating Be star phi Persei was spun up by mass and angular momentum transfer from a now stripped-down, hot subdwarf companion. Here we present the first high angular resolution images of phi Persei made possible by new…

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