Search Publications
Infrared-excess white dwarfs in the Gaia 100 pc sample
Solano, E.; Rebassa-Mansergas, A.; Torres, S. +3 more
We analyse the 100 pc Gaia white dwarf volume-limited sample by means of VOSA (Virtual Observatory SED Analyser) with the aim of identifying candidates for displaying infrared excesses. Our search focuses on the study of the spectral energy distribution (SED) of 3733 white dwarfs with reliable infrared photometry and GBP - GRP
Exploring the M-dwarf Luminosity-Temperature-Radius relationships using Gaia DR2
Naylor, Tim; Morrell, Sam
There is growing evidence that M-dwarf stars suffer radius inflation when compared to theoretical models, suggesting that models are missing some key physics required to completely describe stars at effective temperatures less than about 4000 K. The advent of Gaia DR2 distances finally makes available large data sets to determine the nature and ex…
The metal-rich atmosphere of the exo-Neptune HAT-P-26b
Madhusudhan, Nikku; MacDonald, Ryan J.
Transmission spectroscopy is enabling precise measurements of atmospheric H2O abundances for numerous giant exoplanets. For hot Jupiters, relating H2O abundances to metallicities provides a powerful probe of their formation conditions. However, metallicity measurements for Neptune-mass exoplanets are only now becoming viable.…
Warm FIRE: simulating galaxy formation with resonant sterile neutrino dark matter
Faucher-Giguère, Claude-André; Hopkins, Philip F.; Wetzel, Andrew +8 more
We study the impact of a warm dark matter (WDM) cosmology on dwarf galaxy formation through a suite of cosmological hydrodynamical zoom-in simulations of M_halo ≈ 10^{10} M_{⊙} dark matter haloes as part of the Feedback in Realistic Environments (FIRE) project. A main focus of this paper is to evaluate the combined effects of dark matter physics a…
Host galaxies of high-redshift extremely red and obscured quasars
Brandt, W. N.; Ross, Nicholas P.; Strauss, Michael A. +9 more
We present Hubble Space Telescope 1.4-1.6 µm images of the hosts of 10 extremely red quasars (ERQs) and six type 2 quasar candidates at z = 2-3. ERQs, whose bolometric luminosities range between 1047 and 1048 erg s-1, show spectroscopic signs of powerful ionized winds, whereas type 2 quasar candidates are les…
Spectral variations of Lyman α emission within strongly lensed sources observed with MUSE
Richard, J.; Verhamme, A.; Clément, B. +13 more
We present an analysis of H I Lyman α emission in deep VLT/MUSE observations of two highly magnified and extended galaxies at z=3.5 and 4.03, including a newly discovered, almost complete Einstein ring. While these Lyman α haloes are intrinsically similar to the ones typically seen in other MUSE deep fields, the benefits of gravitational lensing a…
Probing the origin of stellar flares on M dwarfs using TESS data sectors 1-3
Doyle, J. G.; Ramsay, G.; Wu, K. +1 more
Detailed studies of the Sun have shown that sunspots and solar flares are closely correlated. Photometric data from Kepler/K2 has allowed similar studies to be carried out on other stars. Here, we utilize Transiting Exoplanet Survey Satellite (TESS) photometric 2-min cadence of 167 low-mass stars from Sectors 1 to 3 to investigate the relationship…
Overcast on Osiris: 3D radiative-hydrodynamical simulations of a cloudy hot Jupiter using the parametrized, phase-equilibrium cloud formation code EDDYSED
Sing, D. K.; Mikal-Evans, T.; Mayne, N. J. +5 more
We present results from 3D radiative-hydrodynamical simulations of HD 209458b with a fully coupled treatment of clouds using the EDDYSED code, critically, including cloud radiative feedback via absorption and scattering. We demonstrate that the thermal and optical structure of the simulated atmosphere is markedly different, for the majority of our…
Systematic errors in Gaia DR2 astrometry and their impact on measurements of internal kinematics of star clusters
Vasiliev, Eugene
We use stellar proper motions (PM) from Gaia Data Release 2 for studying the internal kinematics of Milky Way globular clusters. In addition to statistical measurement errors, there are significant spatially correlated systematic errors, which cannot be ignored when studying the internal kinematics. We develop a mathematically consistent procedure…
Signatures of an eccentric disc cavity: Dust and gas in IRS 48
Pinte, Christophe; Christiaens, Valentin; van der Marel, Nienke +5 more
We test the hypothesis that the disc cavity in the `transition disc' Oph IRS 48 is carved by an unseen binary companion. We use 3D dust-gas smoothed-particle hydrodynamics simulations to demonstrate that marginally coupled dust grains concentrate in the gas overdensity that forms in the cavity around a low binary mass ratio binary. This produces h…