Search Publications
Spherical symmetry in the kilonova AT2017gfo/GW170817
Kotak, Rubina; Watson, Darach; Sim, Stuart +5 more
The mergers of neutron stars expel a heavy-element enriched fireball that can be observed as a kilonova1-4. The kilonova's geometry is a key diagnostic of the merger and is dictated by the properties of ultra-dense matter and the energetics of the collapse to a black hole. Current hydrodynamical merger models typically show aspherical e…
Outflows from the youngest stars are mostly molecular
Östlin, G.; Güdel, M.; Ray, T. P. +20 more
The formation of stars and planets is accompanied not only by the build-up of matter, namely accretion, but also by its expulsion in the form of highly supersonic jets that can stretch for several parsecs1,2. As accretion and jet activity are correlated and because young stars acquire most of their mass rapidly early on, the most powerf…
A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067
Alonso, R.; Deleuil, M.; Erikson, A. +149 more
Planets with radii between that of the Earth and Neptune (hereafter referred to as `sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate…
Intracluster light is already abundant at redshift beyond unity
Jee, M. James; Joo, Hyungjin
Intracluster light (ICL) is diffuse light from stars that are gravitationally bound not to individual member galaxies, but to the halo of galaxy clusters. Leading theories1,2 predict that the ICL fraction, defined by the ratio of the ICL to the total light, rapidly decreases with increasing redshift, to the level of a few per cent at z …
A close quasar pair in a disk-disk galaxy merger at z = 2.17
Shen, Yue; Oguri, Masamune; Chen, Yu-Ching +7 more
Galaxy mergers produce pairs of supermassive black holes (SMBHs), which may be witnessed as dual quasars if both SMBHs are rapidly accreting. The kiloparsec (kpc)-scale separation represents a physical regime sufficiently close for merger-induced effects to be important1 yet wide enough to be directly resolvable with the facilities curr…
Bipolar outflows out to 10 kpc for massive galaxies at redshift z ≈ 1
Bacon, Roland; Blaizot, Jérémy; Boogaard, Leindert A. +15 more
Galactic outflows are believed to play a critical role in the evolution of galaxies by regulating their mass build-up and star formation1. Theoretical models assume bipolar shapes for the outflows that extend well into the circumgalactic medium (CGM), up to tens of kiloparsecs (kpc) perpendicular to the galaxies. They have been directly…
Spectroscopic identification of water emission from a main-belt comet
Villanueva, Geronimo L.; Bodewits, Dennis; Hsieh, Henry H. +4 more
Main-belt comets are small Solar System bodies located in the asteroid belt that repeatedly exhibit comet-like activity (that is, dust comae or tails) during their perihelion passages, strongly indicating ice sublimation1,2. Although the existence of main-belt comets implies the presence of extant water ice in the asteroid belt, no gas …
15NH3 in the atmosphere of a cool brown dwarf
Henning, Thomas; Östlin, Göran; Colina, Luis +40 more
Brown dwarfs serve as ideal laboratories for studying the atmospheres of giant exoplanets on wide orbits, as the governing physical and chemical processes within them are nearly identical1,2. Understanding the formation of gas-giant planets is challenging, often involving the endeavour to link atmospheric abundance ratios, such as the c…
A super-massive Neptune-sized planet
Schlieder, Joshua E.; Howell, Steve B.; Cubillos, Patricio E. +54 more
Neptune-sized planets exhibit a wide range of compositions and densities, depending on factors related to their formation and evolution history, such as the distance from their host stars and atmospheric escape processes. They can vary from relatively low-density planets with thick hydrogen-helium atmospheres1,2 to higher-density planet…
Resolved imaging confirms a radiation belt around an ultracool dwarf
Kao, Melodie M.; Shkolnik, Evgenya L.; Mioduszewski, Amy J. +1 more
Radiation belts are present in all large-scale Solar System planetary magnetospheres: Earth, Jupiter, Saturn, Uranus and Neptune1. These persistent equatorial zones of relativistic particles up to tens of megaelectron volts in energy can extend further than ten times the planet's radius, emit gradually varying radio emissions2-4