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OAUNI astronomical photometry: stellar variability of FO Aqr on 2016 low state
(IOP Publishing, 2020)
This work reports a photometric monitoring of the intermediate polar cataclysmic variable star FO Aqr. This is part of the ongoing OAUNI stellar variability program. Around 1200 individual measurements (or ∼ 9 hrs of ...
A note on the star order in Hilbert spaces
(Taylor & Francis Ltd, 2010-04)
We study the star order on the algebra L(H) of bounded operators on a Hilbert space H. We present a new interpretation of this order which allows to generalize to this setting many known results for matrices: functional ...
Cyclic variability of the circumstellar disk of the Be star zeta Tauri II. Testing the 2D global disk oscillation model
(EDP SCIENCES S A, 2009)
Context. About 2/3 of the Be stars present the so-called V/R variations, a phenomenon characterized by the quasi-cyclic variation in the ratio between the violet and red emission peaks of the HI emission lines. These ...
Cyclic variability of the circumstellar disk of the Be star zeta Tauri I. Long-term monitoring observations
(EDP SCIENCES S A, 2009)
Context. Emission lines formed in decretion disks of Be stars often undergo long-term cyclic variations, especially in the violet-to-red (V/R) ratio of their primary components. The underlying structural and dynamical ...
Exploring dust around HD 142527 down to 0.025 (4au) using SPHERE/ZIMPOL
(IOP Publishing Ltd., 2017)
We have observed the protoplanetary disk of the well-known young Herbig star HD 142527 using ZIMPOL polarimetric differential imaging with the very broad band (similar to 600-900 nm) filter. We obtained two data sets in ...
Probing the properties of Be star discs with spectroastrometry and NLTE radiative transfer modelling: beta CMi
(WILEY-BLACKWELLHOBOKEN, 2012)
While the presence of discs around classical Be stars is well established, their origin is still uncertain. To understand what processes result in the creation of these discs and how angular momentum is transported within ...
The qWR star HD 45166 - II. Fundamental stellar parameters and evidence of a latitude-dependent wind
(EDP SCIENCES S A, 2008)
Context. The enigmatic object HD 45166 is a qWR star in a binary system with an orbital period of 1.596 day, and presents a rich emission-line spectrum in addition to absorption lines from the companion star (B7 V). As the ...
The dust disk and companion of the nearby AGB star L-2 Puppis SPHERE/ZIMPOL polarimetric imaging at visible wavelengths
(ESO, 2015)
The bright southern star L-2 Pup is a particularly prominent asymptotic giant branch (AGB) star, located at a distance of only 64 pc. We report new adaptive optics observations of L2 Pup at visible wavelengths with the ...