Search Publications
The Evolution and Origin of Ionized Gas Velocity Dispersion from z ∼ 2.6 to z ∼ 0.6 with KMOS3D
Lutz, D.; Wuyts, S.; Förster Schreiber, N. M. +27 more
We present the 0.6 < z < 2.6 evolution of the ionized gas velocity dispersion in 175 star-forming disk galaxies based on data from the full KMOS3D integral field spectroscopic survey. In a forward-modeling Bayesian framework including instrumental effects and beam-smearing, we fit simultaneously the observed galaxy velocity and ve…
Low-frequency gravity waves in blue supergiants revealed by high-precision space photometry
Bowman, Dominic M.; Pope, Benjamin J. S.; White, Timothy R. +14 more
Almost all massive stars explode as supernovae and form a black hole or neutron star. The remnant mass and the impact of the chemical yield on subsequent star formation and galactic evolution strongly depend on the internal physics of the progenitor star, which is currently not well understood. The theoretical uncertainties of stellar interiors ac…
Distances and parallax bias in Gaia DR2
Schönrich, Ralph; Eyer, Laurent; McMillan, Paul
We derive Bayesian distances for all stars in the radial velocity sample of Gaia DR2, and use the statistical method of Schönrich, Binney & Asplund to validate the distances and test the Gaia parallaxes. In contrast to other methods, which rely on special sources, our method directly tests the distances to all stars in our sample. We find clea…
K2 Rotation Periods for Low-mass Hyads and a Quantitative Comparison of the Distribution of Slow Rotators in the Hyades and Praesepe
Cargile, P. A.; Agüeros, M. A.; Douglas, S. T. +4 more
We analyze K2 light curves for 132 low-mass (1 M ⊙ ≳ M * ≳ 0.1 M ⊙) members of the 600-800 Myr old Hyades cluster and measure rotation periods ({P}rot}) for 116 of these stars. These include 93 stars with no prior {P}rot} measurements; the total number of Hyads with a known {P}rot} …
Short GRB 160821B: A Reverse Shock, a Refreshed Shock, and a Well-sampled Kilonova
Pian, E.; Greiner, J.; Fruchter, A. S. +31 more
We report our identification of the optical afterglow and host galaxy of the short-duration gamma-ray burst sGRB 160821B. The spectroscopic redshift of the host is z = 0.162, making it one of the lowest redshift short-duration gamma-ray bursts (sGRBs) identified by Swift. Our intensive follow-up campaign using a range of ground-based facilities as…
TESS Hunt for Young and Maturing Exoplanets (THYME): A Planet in the 45 Myr Tucana-Horologium Association
Barclay, Thomas; Vanderburg, Andrew; Hellier, Coel +49 more
Young exoplanets are snapshots of the planetary evolution process. Planets that orbit stars in young associations are particularly important because the age of the planetary system is well constrained. We present the discovery of a transiting planet larger than Neptune but smaller than Saturn in the 45 Myr Tucana-Horologium young moving group. The…
The discovery of weak coherent pulsations in the ultraluminous X-ray source NGC 1313 X-2
Fabian, A. C.; Pinto, C.; Bachetti, M. +8 more
We report the detection of weak pulsations from the archetypal ultraluminous X-ray source (ULX) NGC 1313 X-2. Acceleration searches reveal sinusoidal pulsations in segments of two out of six new deep observations of this object, with a period of ∼1.5 s and a pulsed fraction of ∼ 5 per cent. We use Monte Carlo simulations to demonstrate that the in…
Evolution of the galaxy stellar mass functions and UV luminosity functions at z = 6-9 in the Hubble Frontier Fields
Conselice, Christopher J.; Bhatawdekar, Rachana; Duncan, Kenneth +1 more
We present new measurements of the evolution of the galaxy stellar mass functions (GSMFs) and ultraviolet luminosity functions (UV LFs) for galaxies from z = 6-9 within the Frontier Field cluster MACSJ0416.1-2403 and its parallel field. To obtain these results, we derive the stellar masses of our sample by fitting synthetic stellar population mode…
A planetesimal orbiting within the debris disc around a white dwarf star
Reffert, Sabine; Toonen, Silvia; Villaver, Eva +29 more
Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We report a stable 123.4-minute periodic variation in the strength and shape of the Ca II emission line profiles originating from the debri…
Protoplanetary Disk Rings and Gaps across Ages and Luminosities
Dong, Ruobing; Williams, Jonathan P.; van der Marel, Nienke +2 more
Since the discovery of the multiring structure of the HL Tau disk, ALMA data suggest that the dust continuum emission of many, if not all, protoplanetary disks consists of rings and gaps, no matter their spectral type or age. The origin of these gaps so far remains unclear. We present a sample study of 16 disks with multiple ring-like structures i…