Search Publications
Microlensing constraints on primordial black holes with Subaru/HSC Andromeda observations
Oguri, Masamune; More, Surhud; Takada, Masahiro +8 more
Primordial black holes (PBHs) have long been suggested as a viable candidate for the elusive dark matter. The abundance of such PBHs has been constrained using a number of astrophysical observations, except for a hitherto unexplored mass window of MPBH = [10-14, 10-9] solar masses. Here we carry out a dense-cadence…
Cosmological Constraints from the Hubble Diagram of Quasars at High Redshifts
Lusso, E.; Risaliti, G.
The concordance model (Λ cold dark matter (ΛCDM) model, where Λ is the cosmological constant) reproduces the main current cosmological observations1-4 assuming the validity of general relativity at all scales and epochs and the presence of CDM and of Λ, equivalent to dark energy with a constant density in space and time. However, the ΛC…
Uncovering the birth of the Milky Way through accurate stellar ages with Gaia
Ruiz-Lara, Tomás; Hill, Vanessa; Monelli, Matteo +4 more
Knowledge of the ages of the stars formed over a galaxy's lifetime is fundamental to an understanding of its formation and evolution. However, stellar ages are difficult to obtain since they cannot be measured from observations, but require comparison with stellar models1. Alternatively, age distributions can be derived by applying the …
Water vapour in the atmosphere of the habitable-zone eight-Earth-mass planet K2-18 b
Tsiaras, Angelos; Tinetti, Giovanna; Yurchenko, Sergey N. +2 more
In the past decade, observations from space and the ground have found water to be the most abundant molecular species, after hydrogen, in the atmospheres of hot, gaseous extrasolar planets1-5. Being the main molecular carrier of oxygen, water is a tracer of the origin and the evolution mechanisms of planets. For temperate, terrestrial p…
A sub-Neptune exoplanet with a low-metallicity methane-depleted atmosphere and Mie-scattering clouds
Deming, Drake; Désert, Jean-Michel; Knutson, Heather A. +15 more
With no analogues in the Solar System, the discovery of thousands of exoplanets with masses and radii intermediate between Earth and Neptune was one of the big surprises of exoplanet science. These super-Earths and sub-Neptunes probably represent the most common outcome of planet formation1,2. Mass and radius measurements indicate a div…
Kinematic detection of a planet carving a gap in a protoplanetary disk
Pinte, C.; Ménard, F.; Duchêne, G. +10 more
We still do not understand how planets form or why extrasolar planetary systems are so different from our own Solar System. However, the past few years have dramatically changed our view of the disks of gas and dust around young stars. Observations with the Atacama Large Millimeter/submillimeter Array and extreme adaptive-optics systems have revea…
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…
A comprehensive three-dimensional radiative magnetohydrodynamic simulation of a solar flare
Cheung, M. C. M.; De Pontieu, B.; Sainz Dalda, A. +11 more
Solar and stellar flares are the most intense emitters of X-rays and extreme ultraviolet radiation in planetary systems1,2. On the Sun, strong flares are usually found in newly emerging sunspot regions3. The emergence of these magnetic sunspot groups leads to the accumulation of magnetic energy in the corona. When the magneti…
The ice composition in the disk around V883 Ori revealed by its stellar outburst
Johnstone, Doug; Lee, Jeong-Eun; Aikawa, Yuri +6 more
Complex organic molecules (COMs), which are the seeds of prebiotic material and precursors of amino acids and sugars, form in the icy mantles of circumstellar dust grains1 but cannot be detected remotely unless they are heated and released to the gas phase. Around solar-mass stars, water and COMs only sublimate in the inner few uc(au) o…
A super-Earth and two sub-Neptunes transiting the nearby and quiet M dwarf TOI-270
Vanderburg, Andrew; Latham, David W.; Quinn, Samuel N. +57 more
One of the primary goals of exoplanetary science is to detect small, temperate planets passing (transiting) in front of bright and quiet host stars. This enables the characterization of planetary sizes, orbits, bulk compositions, atmospheres and formation histories. These studies are facilitated by small and cool M dwarf host stars. Here we report…