Search Publications
A core in a star-forming disc as evidence of inside-out growth in the early Universe
Chevallard, Jacopo; Maseda, Michael V.; Carniani, Stefano +36 more
The physical processes that establish the morphological evolution and the structural diversity of galaxies are key unknowns in extragalactic astrophysics. Here we report the finding of the morphologically mature galaxy JADES-GS+53.18343−27.79097, which existed within the first 700 million years of the Universe's history. This star-forming galaxy w…
Multiwavelength constraints on the origin of a nearby repeating fast radio burst source in a globular cluster
Kaspi, Victoria M.; Smith, Kendrick M.; Güver, Tolga +26 more
The precise origins of fast radio bursts (FRBs) remain unknown. Multiwavelength observations of nearby FRB sources can provide important insights into the enigmatic FRB phenomenon. Here we present results from a sensitive, broadband X-ray and radio observational campaign of FRB 20200120E, the closest known extragalactic repeating FRB source (locat…
Photometric detection at 7.7 µm of a galaxy beyond redshift 14 with JWST/MIRI
Pérez-González, Pablo G.; Charlot, Stéphane; Chevallard, Jacopo +31 more
The James Webb Space Telescope (JWST) has spectroscopically confirmed numerous galaxies at z > 10. While weak rest-frame ultraviolet emission lines have only been seen in a handful of sources, the stronger rest-frame optical emission lines are highly diagnostic and accessible at mid-infrared wavelengths with the Mid-Infrared Instrument (MIRI) o…
The formation and survival of the Milky Way's oldest stellar disk
Xiang, Maosheng; Huang, Yang; Liu, Jifeng +3 more
It remains a mystery when our Milky Way first formed a stellar disk component that survived and maintained its disk structure from subsequent galaxy mergers. We present a study of the age-dependent structure and star formation rate of the Milky Way's disk using high-α stars with substantial orbital angular momentum that have precise age determinat…
Observation of super-Alfvénic slippage of reconnecting magnetic field lines on the Sun
Polito, Vanessa; De Pontieu, Bart; Aulanier, Guillaume +3 more
Slipping motions of magnetic field lines are a distinct signature of three-dimensional magnetic reconnection, a fundamental process driving solar and stellar flares. While being a key prediction of numerical experiments, the rapid super-Alfvénic field line slippage driven by the `slip-running' reconnection has remained elusive in previous observat…
Enigmatic ice leaves cold trail
Woods, Paul
Evidence for heavy-seed origin of early supermassive black holes from a z ≈ 10 X-ray quasar
Churazov, Eugene; Goulding, Andy D.; Jones, Christine +9 more
Observations of quasars reveal that many supermassive black holes (BHs) were in place less than 700 Myr after the Big Bang. However, the origin of the first BHs remains a mystery. Seeds of the first BHs are postulated to be either light (that is, 10‑100 M⊙), remnants of the first stars, or heavy (that is, 10‑105 M⊙…
A fast-rotator post-starburst galaxy quenched by supermassive black-hole feedback at z = 3
Pérez-González, Pablo G.; Chevallard, Jacopo; Parlanti, Eleonora +23 more
The most massive galaxies in the Universe stopped forming stars due to the time-integrated feedback from central supermassive black holes (SMBHs). However, the exact quenching mechanism is not yet understood, because local massive galaxies were quenched billions of years ago. Here we present JWST/NIRSpec integral-field spectroscopy observations of…
Deciphering Lyman-α emission deep into the epoch of reionization
Pérez-González, Pablo G.; Santini, Paola; Grogin, Norman A. +18 more
During the epoch of reionization, the first galaxies were enshrouded in pristine neutral gas, with one of the brightest emission lines in star-forming galaxies, Lyman α (Lyα), expected to remain undetected until the Universe became ionized. Providing an explanation for the surprising detection of Lyα in these early galaxies is a major challenge fo…
X-ray eruptions every 22 days from the nucleus of a nearby galaxy
Gendreau, Keith; van Velzen, Sjoert; Gezari, Suvi +15 more
Galactic nuclei showing recurrent phases of activity and quiescence have recently been discovered. Some have recurrence times as short as a few hours to a day and are known as quasi-periodic X-ray eruption (QPE) sources. Others have recurrence times as long as hundreds to a thousand days and are called repeating nuclear transients. Here we present…