Search Publications
Evidence for the volatile-rich composition of a 1.5-Earth-radius planet
Fortney, Jonathan J.; Knutson, Heather A.; Angus, Ruth +18 more
The population of planets smaller than approximately 1.7 Earth radii (R⊕) is widely interpreted as consisting of rocky worlds, generally referred to as super-Earths. This picture is largely corroborated by radial velocity mass measurements for close-in super-Earths but lacks constraints at lower insolations. Here we present the results …
Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky
Richard, Johan; Riddle, Reed; Wheeler, J. Craig +35 more
Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfectly aligned foreground galaxy that deflects light towards the observer. Here we describe how…
An assessment of the association between a fast radio burst and binary neutron star merger
Zhang, Bing; Moroianu, Alexandra; Wen, Linqing +4 more
Fast radio bursts (FRBs) are bright millisecond-duration radio bursts at cosmological distances. While young magnetars are the leading source candidate, recent observations suggest that there may be multiple FRB progenitor classes. Here we investigate a potential coincidence between a binary neutron star merger event, GW190425, and a bright, non-r…
Magnetar spin-down glitch clearing the way for FRB-like bursts and a pulsed radio episode
Lin, L.; Kouveliotou, C.; Baring, M. G. +16 more
Magnetars are a special subset of the isolated neutron star family, with X-ray and radio emission mainly powered by the decay of their immense magnetic fields. Many attributes of magnetars remain poorly understood: spin-down glitches or the sudden reductions in the star's angular momentum, radio bursts reminiscent of extragalactic fast radio burst…
The Milky Way's plane of satellites is consistent with ΛCDM
Jenkins, Adrian; Frenk, Carlos; Helly, John +7 more
The Milky Way is surrounded by 11 `classical' satellite galaxies in a remarkable configuration: a thin plane that is possibly rotationally supported. Such a structure is thought to be highly unlikely to arise in the standard (ΛCDM) cosmological model (Λ cold dark matter model, where Λ is the cosmological constant). While other apparent discrepanci…
A calibration point for stellar evolution from massive star asteroseismology
Bowman, Dominic M.; Vanderspek, Roland; Aerts, Conny +10 more
Massive stars are progenitors of supernovae, neutron stars and black holes. During the hydrogen-core burning phase, their convective cores are the prime drivers of their evolution, but inferences of core masses are subject to unconstrained boundary mixing processes. Moreover, uncalibrated transport mechanisms can lead to strong envelope mixing and…
Sub-per-cent determination of the brightness at the tip of the red giant branch in the Magellanic Clouds
Hoyt, Taylor J.
The value of the Hubble constant as constrained by type Ia supernovae is directly tied to the zero point of the extragalactic distance scale, which is in turn set by the calibration of astrophysical distance indicators such as the tip of the red giant branch (TRGB). In this article, a calibration of the TRGB luminosity is determined in the Magella…
A 5.3-min-period pulsing white dwarf in a binary detected from radio to X-rays
Kepler, S. O.; Heywood, I.; Dhillon, V. S. +19 more
White dwarf stars are the most common stellar fossils. When in binaries, they make up the dominant form of compact object binary within the Galaxy and can offer insight into different aspects of binary formation and evolution. One of the most remarkable white dwarf binary systems identified to date is AR Scorpii (AR Sco). AR Sco is composed of an …
Coherent radio bursts from known M-dwarf planet-host YZ Ceti
Pineda, J. Sebastian; Villadsen, Jackie
Observing magnetic star-planet interactions (SPIs) offers promise for determining the magnetic fields of exoplanets. Models of sub-Alfvénic SPIs predict that terrestrial planets in close-in orbits around M dwarfs can induce detectable stellar radio emission, manifesting as bursts of strongly polarized coherent radiation observable at specific plan…
A long-duration gamma-ray burst of dynamical origin from the nucleus of an ancient galaxy
Fruchter, Andrew S.; Heintz, Kasper E.; Jonker, Peter G. +29 more
The majority of long-duration (>2 s) gamma-ray bursts (GRBs) arise from the collapse of massive stars, with a small proportion created from the merger of compact objects. Most of these systems form via standard stellar evolution pathways. However, a fraction of GRBs may result from dynamical interactions in dense environments. These channels co…