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Related papers: Polarization measurements of Vega-like stars

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We report observations of the linear polarization of a sample of 49 nearby bright stars measured to sensitivities of between ~1 and 4 x 10^-6. The majority of stars in the sample show measurable polarization, but most polarizations are…

Solar and Stellar Astrophysics · Physics 2015-05-18 Jeremy Bailey , P. W. Lucas , J. H. Hough

Vega, the second brightest star in the northern hemisphere, serves as a primary spectral type standard. While its spectrum is dominated by broad hydrogen lines, the narrower lines of the heavy elements suggested slow to moderate rotation,…

We carried out a search for M-type Vega-like stars by correlating the IRAS Faint Source Catalog with Hipparcos selected M-type stars. Three stars with apparent IRAS 25mu excess emission are shown instead to be non-IR-excess stars from…

Astrophysics · Physics 2009-11-07 Inseok Song , A. Weinberger , E. Becklin , B. Zuckerman , C. Chen

Mira and semi-regular variable stars have been studied for centuries but continue to be enigmatic. One unsolved mystery is the presence of polarization from these stars. In particular, we present 40 years of polarization measurements for…

Solar and Stellar Astrophysics · Physics 2015-06-17 Hilding R. Neilson , Richard Ignace , Gary D. Henson

We report observations of the linear polarisation of a sample of 50 nearby southern bright stars measured to a median sensitivity of $\sim$4.4 $\times 10^{-6}$. We find larger polarisations and more highly polarised stars than in the…

Solar and Stellar Astrophysics · Physics 2017-03-29 Daniel V. Cotton , Jeremy Bailey , Lucyna Kedziora-Chudczer , Kimberly Bott , P. W. Lucas , J. H. Hough , Jonathan P. Marshall

In this work we present a revised measurement of the phase-averaged optical polarisation of the Vela pulsar (PSR B0833-45), for which only one value has been published so far (Wagner & Seifert 2000). Our measurement has been obtained…

Astrophysics · Physics 2009-11-13 R. P. Mignani , S. Bagnulo , J. Dyks , G. Lo Curto , A. Slowikowska

Galactic dust emission is polarized at unexpectedly high levels, as revealed by Planck. The origin of the observed $\simeq 20\%$ polarization fractions can be identified by characterizing the properties of optical starlight polarization in…

Astrophysics of Galaxies · Physics 2019-04-17 G. V. Panopoulou , B. S. Hensley , R. Skalidis , D. Blinov , K. Tassis

Polarization is a powerful tool for understanding stellar atmospheres and circumstellar environments. Mira and semi-regular variable stars have been observed for decades and some are known to be polarimetrically variable, however, the…

Solar and Stellar Astrophysics · Physics 2015-06-22 Hilding R. Neilson , Richard Ignace , Beverly J. Smith , Gary Henson , Alyssa M. Adams

We calculate the degree of linear polarization of radiation from stars having planets that may not be resolved spatially. We assume single scattering by water and silicate particulates in the planetary atmosphere. The dilution of the…

Astrophysics · Physics 2009-11-13 Sujan Sengupta , Malay Maiti

The recent discovery of a weak surface magnetic field on the normal intermediate-mass star Vega raises the question of the origin of this magnetism in a class of stars that was not known to host magnetic fields. We aim to confirm the field…

Solar and Stellar Astrophysics · Physics 2015-05-19 P. Petit , F. Lignières , G. A. Wade , M. Aurière , T. Böhm , S. Bagnulo , B. Dintrans , A. Fumel , J. Grunhut , J. Lanoux , A. Morgenthaler , V. Van Grootel

New-generation X-ray polarimeters currently under development promise to open a new window in the study of high-energy astrophysical sources. Among them, neutron stars appear particularly suited for polarization measurements. Radiation from…

High Energy Astrophysical Phenomena · Physics 2015-09-24 Roberto Taverna , Roberto Turolla , Denis Gonzalez Caniulef , Silvia Zane , Fabio Muleri , Paolo Soffitta

Aligned interstellar grains produce polarized extinction (observed at wavelengths from the far-ultraviolet to the mid-infrared), and polarized thermal emission (observed at far-infrared and submm wavelengths). The grains must be quite…

Astrophysics of Galaxies · Physics 2025-04-07 B. T. Draine

We report the detection of a magnetic field on Vega through spectropolarimetric observations. We acquired 257 Stokes V, high signal-to-noise and high-resolution echelle spectra during four consecutive nights with the NARVAL…

Solar and Stellar Astrophysics · Physics 2015-05-13 F. Lignieres , P. Petit , T. Bohm , M. Auriere

Recently we have demonstrated that high-precision polarization observations can detect the polarization resulting from the rotational distortion of a rapidly rotating B-type star. Here we investigate the extension of this approach to an…

Solar and Stellar Astrophysics · Physics 2020-04-01 Jeremy Bailey , Daniel V. Cotton , Ian D. Howarth , Fiona Lewis , Lucyna Kedziora-Chudczer

As is known, resonant scattering can distort the surface-brightness profiles of clusters of galaxies in X-ray lines. We demonstrate that the scattered line emission should be polarized and possibly detectable with near-future X-ray…

Astrophysics · Physics 2009-11-07 S. Sazonov , E. Churazov , R. Sunyaev

This paper presents optical UBVRI broadband photo-polarimetry of the EXPORT sample obtained at the 2.5m Nordic Optical Telescope. The database consists of multi-epoch photo-polarimetry of 68 pre-main-sequence and main-sequence stars. An…

Astrophysics · Physics 2009-11-07 R. D. Oudmaijer , J. Palacios , C. Eiroa , the EXPORT collaboration

We investigate the linear polarization in the light of extrasolar planetary systems that may arise as a result of an occultation of the star by a transiting planet. Such an occultation breaks any spherical symmetry over the projected…

Astrophysics · Physics 2009-11-13 A. C. Carciofi , A. M. Magalhaes

New observations of 9 of the brightest northern O stars have been made with the Breger polarimeter on the 0.9~m telescope at McDonald Observatory and the AnyPol polarimeter on the 0.4~m telescope at Limber Observatory, using the…

Astrophysics · Physics 2009-10-31 David McDavid

We present optical (UBVRI) linear polarimetric observations of 8 Wolf-Rayet (WR) massive binaries and single stars. We have corrected the observed values for the interstellar extinction and polarization by the interstellar medium to obtain…

Astrophysics of Galaxies · Physics 2013-09-05 Stavros Akras , Julio Ramirez-Velez , David Hiriart , Jose Manuel Lopez

We have measured the optical linear polarization of quasars belonging to Gpc-scale quasar groups at redshift z ~ 1.3. Out of 93 quasars observed, 19 are significantly polarized. We found that quasar polarization vectors are either parallel…

Astrophysics of Galaxies · Physics 2014-11-19 Damien Hutsemékers , Lorraine Braibant , Vincent Pelgrims , Dominique Sluse
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