Search Publications
The role of multiple images and model priors in measuring H0 from supernova Refsdal in galaxy cluster MACS J1149.5+2223
Liesenborgs, Jori; Williams, Liliya L. R.
Multiple image gravitational lensing systems with measured time delays provide a promising one-step method for determining H0. MACS J1149, which lenses SN Refsdal into a quad S1-S4, and two other widely separated images, SX and SY, is a perfect candidate. If time delays are pinned down, the remaining uncertainty arises from the mass dis…
The HST/ACS star formation history of the Tucana dwarf spheroidal galaxy: clues from the horizontal branch
Salaris, M.; Monelli, M.; Tolstoy, E. +2 more
We report a new star formation history for the Tucana dwarf spheroidal galaxy, obtained from a new look at a deep HST/ACS colour-magnitude diagram. We combined information from the main sequence turn-off and the horizontal branch to resolve the ancient star formation rates on a finer temporal scale than previously possible. We show that Tucana exp…
A Confined Partial Eruption of Double-decker Filaments
Yang, Shuhong; Chen, Yao; Zheng, Ruisheng +6 more
Filament eruptions, one of the most energetic explosions on the Sun, release large quantities of magnetized plasma into the interplanetary space. Hence, the understanding of the initiation and evolution of filament eruptions can provide broader implications for space weather and geospace climate. Here, we present a confined partial eruption of dou…
The Most Massive Galaxies with Large Depleted Cores: Structural Parameter Relations and Black Hole Masses
Dullo, Bililign T.
Luminous spheroids (M V ≲ -21.50 ± 0.75 mag) contain partially depleted cores with sizes (R b) typically 0.02-0.5 kpc. However, galaxies with R b > 0.5 kpc are rare and poorly understood. Here, we perform detailed decompositions of the composite surface brightness profiles, extracted from archival Hubble Space…
The structural properties of classical bulges and discs from z ∼ 2
Barro, Guillermo; Pérez-González, Pablo G.; Kocevski, Dale D. +19 more
We study the rest-frame optical mass-size relation of bulges and discs from z ∼ 2 to z ∼ 0 for a complete sample of massive galaxies in the CANDELS fields using two-component Sérsic models. Discs and star-forming galaxies follow similar mass-size relations. The mass-size relation of bulges is less steep than the one of quiescent galaxies (best-fit…
Rotational Light Curves of Jupiter from Ultraviolet to Mid-infrared and Implications for Brown Dwarfs and Exoplanets
Fletcher, Leigh N.; Zhang, Xi; Orton, Glenn S. +7 more
Rotational modulations are observed on brown dwarfs and directly imaged exoplanets, but the underlying mechanism is not well understood. Here we analyze Jupiter’s rotational light curves at 12 wavelengths from the ultraviolet (UV) to the mid-infrared (mid-IR). The peak-to-peak amplitudes of Jupiter’s light curves range from subpercent to 4% at mos…
Spatially Resolved Metal Loss from M31
Williams, Benjamin F.; Dalcanton, Julianne J.; Werk, Jessica K. +1 more
As galaxies evolve, they must enrich and exchange gas with the surrounding medium, but the timing of these processes and how much gas is involved remain poorly understood. In this work, we leverage metals as tracers of past gas flows to constrain the history of metal ejection and redistribution in M31. This roughly L* galaxy is a unique case where…
The CARMENES search for exoplanets around M dwarfs. The enigmatic planetary system GJ 4276: one eccentric planet or two planets in a 2:1 resonance?
Schmitt, J. H. M. M.; Nagel, E.; Amado, P. J. +25 more
We report the detection of a Neptune-mass exoplanet around the M4.0 dwarf GJ 4276 (G 232-070) based on radial velocity (RV) observations obtained with the CARMENES spectrograph. The RV variations of GJ 4276 are best explained by the presence of a planetary companion that has a minimum mass of mb sin i ≈ 16 M⊕ on a Pb
SDSS J075101.42+291419.1: A Super-Eddington Accreting Quasar with Extreme X-Ray Variability
Brandt, W. N.; Luo, B.; Gallagher, S. C. +6 more
We report the discovery of extreme X-ray variability in a type 1 quasar: SDSS J075101.42+291419.1. It has a black hole (BH) mass of 1.6 × 107 M ⊙ measured from reverberation mapping, and the BH is accreting with a super-Eddington accretion rate. Its XMM-Newton observation in 2015 May reveals a flux drop by a factor of ∼22 wit…
NOEMA maps the CO J = 2 - 1 environment of the red supergiant µ Cep
Decin, L.; Richards, A. M. S.; Royer, P. +8 more
Red supergiant stars are surrounded by a gaseous and dusty circumstellar environment created by their mass loss, which spreads heavy elements into the interstellar medium. The structure and dynamics of this envelope are crucial to understand the processes driving the red supergiant mass loss and the shaping of the pre-supernova ejecta. We have obs…