Related papers: Orbits in the T Tauri triple system observed with …

Nearby associations are excellent objects for the study of the initial spin up phase during the PMS evolution. An empirical approach is adopted here to infer their rotations properties and relations to X-ray emission. Three nearby…

It is now accepted that accretion onto classical T Tauri stars is controlled by the stellar magnetosphere, yet to date most accretion models have assumed that their magnetic fields are dipolar. By considering a simple steady state accretion…

Measurements of masses and ages of young stars from their location in the HR diagram are limited by not only the typical observational uncertainties that apply to field stars, but also by large systematic uncertainties related to…

TWA 3A is the most recent addition to a small group of young binary systems that both actively accrete from a circumbinary disk and have spectroscopic orbital solutions. As such, it provides a unique opportunity to test binary accretion…

Sylvia is a triple asteroid system located in the main belt. We report new adaptive optics observations of this system that extend the baseline of existing astrometric observations to a decade. We present the first fully dynamical 3-body…

How T Tauri stars remain slowly rotating while still accreting material is a long-standing puzzle. Current models suggest that these stars may lose angular momentum through magnetospheric ejections of disk material (MEs) and…

We re-analyze the global orbital architecture and dynamical stability of the $\mu$ Arae planetary system. We have updated the best-fit elements and minimal masses of the planets based on literature radial velocity (RV) measurements, now…

The YY Ori stars are T Tauri stars with prominent time-variable redshifted absorption components that flank certain emission lines. One of the brightest in this class is S CrA, a visual double star. We have obtained a series of…

We report the analysis, conducted as part of the MaTYSSE programme, of a spectropolarimetric monitoring of the ~0.8 Myr, ~1.4 MSun disc-less weak-line T Tauri star V410 Tau with the ESPaDOnS instrument at the Canada-France-Hawaii Telescope…

The SHINE project is a 500-star survey performed with SPHERE on the VLT for the purpose of directly detecting new substellar companions and understanding their formation and early evolution. Here we present an initial statistical analysis…

We present Halpha spectropolarimetry observations of a sample of 10 bright T Tauri stars, supplemented with new Herbig Ae/Be star data. A change in the linear polarisation across Halpha is detected in most of the T Tauri (9/10) and Herbig…

Mass accretion from the circumstellar disk onto the protostar is a fundamental process during star formation. Measuring the mass accretion rate is particularly challenging for stars belonging to binary systems, because it is often difficult…

We present orbital elements, orbital parallaxes and individual component masses, for fourteen spatially resolved double-line spectroscopic binaries derived doing a simultaneous fit of their visual orbit and radial velocity curve. This was…

The alignment of planetary orbits with respect to the stellar rotation preserves information on their dynamical histories. Measuring this angle for young planets help illuminate the mechanisms that create misaligned orbits for older…

New high-resolution adaptive optics systems provide an unprecedentedly detailed view of nearby star forming regions. In particular, young nearby T Tauri stars can be probed at much smaller physical scales (a few AU) than possible just a…

We successfully measured the trigonometric parallax of Sagittarius A* (Sgr A*) to be $117\pm17$ micro-arcseconds ($\mu$as) using the VLBI Exploration of Radio Astrometry (VERA) with the newly developed broad-band signal-processing system…

A radial velocity study by Donati et al. (2016) reported the detection of a close-in giant planet in a 4.93 d orbit around the ~2 Myr old weak-lined T Tauri star V830 Tau. Because of the stringent timescale constraints that a very young…

Classical T Tauri stars are newly formed, low mass stars which may display both periodic and random variations in their brightness. The interaction between the star and its circumstellar disk is time-dependent, leading to short or long-term…

SPHERE is the high-contrast exoplanet imager and spectrograph installed at the Unit Telescope 3 of the Very Large Telescope. After more than two years of regular operations, we analyse statistically the performance of the adaptive optics…

From observations collected with the ESPaDOnS and NARVAL spectropolarimeters, we report the detection of Zeeman signatures on the classical T Tauri star BP Tau. Circular polarisation signatures in photospheric lines and in narrow emission…