Search Publications
Slowly cooling white dwarfs in M13 from stable hydrogen burning
Cadelano, Mario; Pallanca, Cristina; Dalessandro, Emanuele +5 more
White dwarfs (WDs) are the final evolutionary product of the vast majority of stars in the Universe. They are electron-degenerate structures characterized by no stable thermonuclear activity, and their evolution is generally described as a pure cooling process. Their cooling rate is adopted as cosmic chronometer to constrain the age of several Gal…
Optical and ultraviolet pulsed emission from an accreting millisecond pulsar
D'Avanzo, P.; Campana, S.; Stella, L. +28 more
Millisecond spinning, low-magnetic-field neutron stars are believed to attain their fast rotation in a 0.1-1-Gyr-long phase during which they accrete matter endowed with angular momentum from a low-mass companion star1. Despite extensive searches, coherent periodicities originating from accreting neutron star magnetospheres have been de…
A titanic interstellar medium ejection from a massive starburst galaxy at redshift 1.4
Calabrò, Antonello; Circosta, Chiara; Perna, Michele +12 more
Feedback-driven winds from star formation or active galactic nuclei might be a relevant channel for the abrupt quenching of star formation in massive galaxies. However, both observations and simulations support the idea that these processes are non-conflictingly co-evolving and self-regulating. Furthermore, evidence of disruptive events that are c…
Infrared spectropolarimetric detection of intrinsic polarization from a core-collapse supernova
Tinyanont, Samaporn; Leonard, Douglas C.; De, Kishalay +8 more
Massive stars die an explosive death as a core-collapse supernova (CCSN). The exact physical processes that cause the collapsing star to rebound into an explosion are not well understood1-3, and the key to resolving this issue may lie in the measurement of the shape of CCSNe ejecta. Spectropolarimetry is the only way to perform this mea…
A possible bright ultraviolet flash from a galaxy at redshift z ≈ 11
Ho, Luis C.; Jiang, Linhua; Cai, Zheng +8 more
In the optical sky, minutes-duration transients from cosmological distances are rare. Known objects that give rise to such transients include gamma-ray bursts (GRBs), the most luminous explosions in the Universe1 that have been detected at redshifts as high as z ≈ 9.4 (refs. 2-4). These high-redshift GRBs and their associated…
A [C II] 158 µm emitter associated with an O I absorber at the end of the reionization epoch
Hennawi, Joseph F.; Fan, Xiaohui; Prochaska, J. Xavier +11 more
The physical and chemical properties of the circumgalactic medium at z ≳ 6 have been studied successfully through the absorption in the spectra of background quasi-stellar objects1-3. One of the most crucial questions is to investigate the nature and location of the source galaxies that give rise to these early metal absorbers4-6
A possible planet candidate in an external galaxy detected through X-ray transit
Soria, Roberto; Urquhart, Ryan; Kashyap, Vinay L. +4 more
Many lines of reasoning suggest that external galaxies should host planetary systems, but detecting them by methods typically used in our own Galaxy is not possible. An alternative approach is to study the temporal behaviour of X-rays emitted by bright extragalactic X-ray sources, where an orbiting planet would temporarily block the X-rays and cau…
Optical reconstruction of dust in the region of supernova remnant RX J1713.7−3946 from astrometric data
Krone-Martins, A.; Rowell, G.; Fukui, Y. +5 more
The origin of the radiation observed in the region of the supernova remnant RX J1713.7−3946, one of the brightest TeV emitters, has been debated since its discovery. The existence of atomic and molecular clouds in this object supports the idea that part of the GeV gamma-ray emission in this region originates from proton-proton collisions. However,…
The recurrent impact of the Sagittarius dwarf on the star formation history of the Milky Way
Ruiz-Lara, Tomás; Bernard, Edouard J.; Cassisi, Santi +1 more
Satellites orbiting disk galaxies can induce phase space features such as spirality, vertical heating and phase-mixing in their disks. Such features have also been observed in our own Galaxy, but the complexity of the Milky Way disk has only recently been fully mapped by Gaia Data Release 2 (DR2) data. This complex behaviour is mainly ascribed to …
Resonance locking in giant planets indicated by the rapid orbital expansion of Titan
Fuller, Jim; Modenini, Dario; Tortora, Paolo +8 more
Saturn is orbited by dozens of moons, and the intricate dynamics of this complex system provide clues about its formation and evolution. Tidal friction within Saturn causes its moons to migrate outwards, driving them into orbital resonances that pump their eccentricities or inclinations, which in turn leads to tidal heating of the moons. However, …