Related papers: Dynamical Mass Measurement of the Young Spectrosco…
We present moderate resolution (R $\sim$ 3575) optical spectra of 19 known or suspected members of the AB Doradus and $\beta$ Pictoris Moving Groups, obtained with the DeVeny Spectrograph on the 72-inch Perkins telescope at Lowell…
There is evidence in the 125-Myr Pleiades cluster, and more recently in the 5-Myr NGC 2264 cluster, that rotation plays a key role in the Lithium (Li) depletion processes among low-mass stars. Fast rotators appear to be less Li-depleted…
We have carried out high contrast imaging of 70 young, nearby B and A stars to search for brown dwarf and planetary companions as part of the Gemini NICI Planet-Finding Campaign. Our survey represents the largest, deepest survey for planets…
We present a photometric $J$-band variability study of GU Psc b, a T3.5 co-moving planetary-mass companion (9-13$M_{\rm{Jup}}$) to a young ($\sim$150 Myr) M3 member of the AB Doradus Moving Group. The large separation between GU Psc b and…
We present Keck laser guide star adaptive optics imaging of the M8+M8 binary 2MASS J2206-2047AB. Together with archival HST, Gemini-North, and VLT data, our observations span 8.3 years of the binary's 35 year orbital period, and we…
New uvby-\beta data are provided for 442 high-velocity and metal-poor stars; 90 of these stars have been observed previously by us, and 352 are new. When combined with our previous two photometric catalogues, the data base is now made up of…
We present new observations of the low-mass companion to HD 984 taken with the Gemini Planet Imager as a part of the Gemini Planet Imager Exoplanet Survey campaign. Images of HD 984 B were obtained in the J (1.12--1.3 micron) and H…
We analyze new/archival VLT/NaCo and Gemini/NICI high-contrast imaging of the young, self-luminous planet $\beta$ Pictoris b in seven near-to-mid IR photometric filters, using advanced image processing methods to achieve high…
Measuring the chemical and isotopic compositions of gas giants and brown dwarfs provides insights into their formation pathways and birth environments. 2MASS J0249-0557 c is an L2-type planetary mass companion ($\sim 12 M_{\mathrm{Jup}}$)…
The identification and characterisation of low-mass binaries is of importance for a range of astrophysical investigations. Low-mass binaries in young ($\sim10 - 100 $ Myr) moving groups (YMGs) are of particular significance as they provide…
We present and analyze long-term optical photometric measurements of the three active stars V2253 Oph, IT Com and IS Vir. All three systems are single-lined spectroscopic binaries with an early K giant as primary component but in different…
Context. Intrinsic H$\alpha$ emission can be advantageously used to detect substellar companions because it improves contrasts in direct imaging. Characterising this emission from accreting exoplanets allows for the testing of planet…
The third body is expected to shape the formation and evolution of close binary systems. In this work, we develop a method to detect and characterize the tertiary companion around eclipsing binaries through the combined analysis of eclipse…
Nearly 15 years of radial velocity (RV) monitoring and direct imaging enabled the detection of two giant planets orbiting the young, nearby star $\beta$ Pictoris. The $\delta$ Scuti pulsations of the star, overwhelming planetary signals,…
We have obtained a Gemini South T-ReCS Qa-band (18.3 micron) image and a Spitzer MIPS SED-mode observation of HD181327, an F5/F6V member of the ~12 Myr old beta Pictoris moving group. We resolve the disk in thermal-emission for the first…
We present recent measurements of the orbital motion in the binaries, DF Tau and ZZ Tau, and in the triples, Elias 12, T Tau, and V853 Oph. We observed these systems with the Fine Guidance Sensors on the Hubble Space Telescope and with…
We analyze photometry and spectra of the "redback" millisecond pulsar binary J2339$-$0533. These observations include new measurements from Keck and GROND, as well as archival measurements from the OISTER, WIYN, SOAR, and HET telescopes.…
Very Long Baseline Interferometry (VLBI) provides high angular resolution images and has been used for stellar astrometry for decades. The DYNAMO-VLBA project utilizes the Very Long Baseline Array (VLBA) to study tight binary and multiple…
$\beta$ Pictoris is a young nearby A5V star, about 20 Myr old, embedded in a prominent debris disc. For the past 40 years, variable absorption features have been observed in the stellar spectrum, produced by the gaseous tails of exocomets…
Aims. Measuring dynamical masses of substellar companions is a powerful tool to test models of mass-luminosity-age relations, as well as determining observational features that constrain the boundary between stellar and substellar…