Tag: kepler

Different regimes of particle acceleration in supernova remnants. The study: “A Spatially Resolved Study of Hard X-Ray Emission in Kepler’s Supernova Remnant: Indications of Different Regimes of Particle Acceleration” of V. Sapienza (UNIPA/OAPA) appeared on ApJ

Ricerca

Cosmic rays are high-energy charged particles which continuously hit our planet. These particles are accelerated up to such high velocities in different astronomical environments, among which supernova remnants seems to be particularly important. These objects are nebulae in rapid expansion generated by the explosions of very massive stars. In supernova remnants, particle acceleration seems to occurr along the expanding shock

» Read more
, , , , , , , ,

How to correct from systematics high-precision photometric data. The study: “Principal component analysis to correct data systematics. Case study: K2 light curves” of A. Petralia (INAF-OAPA) recently appeared on Experimental Astronomy

Ricerca

Several fields in modern astronomy rely on high-precision photometric data. This is true, in particular, for the search of exoplanets with the method of transits. This method consists in searching very small periodic dimming of stellar emission due to the transit of planets along the line of sight during their orbits. For instance, the transit due to a Hot Jupiter (a gaseous

» Read more
, , , ,

Planets with ultra-short period. The study: “An ultra-short period rocky super-Earth orbiting the G2-star HD 80653” of G. Frustagli (INAF – Astronomical Observatory of Brera) recently appeared on A&A

Ricerca

The “Ultra-Short Period” (USP) exoplanets have very close orbits and orbital periods shorter than one day. These planets typically have a radius smaller than 2 Earth radii and a terrestrial composition, sometime with an excess of iron.   Four hypotheses have been made to explain the formation and evolution of USP planets. The main hypothesis is that these planets originate

» Read more
, , ,

Super-flares in the Pleiades. The study: “Simultaneous Kepler/K2 and XMM-Newton observations of superflares in the Pleiades” of M. G. Guarcello (INAF-OAPA) recently appeared on A&A

Ricerca

Observations of the Sun show that our star hosts transient and violent phenomena which are due to the interaction between the plasma and the magnetic field produced in the interior of the Sun. Typical examples of this “magnetic activity” are the sunspots in the photosphere and the protuberances in the chromosphere. The solar flares are among those phenomena associated with

» Read more
, , , , , ,

A sub-Neptunian planet discovered around a G9 star. Published on MNRAS: “K2-263 b: a 50 d period sub-Neptune with a mass measurement using HARPS-N” of A. Mortier (University of St. Andrews)

Ricerca

The search of exoplanets relies mainly on two techniques: transits and radial velocity. With the former method exoplanets are revealed thanks to small and periodic dimming of the light of stars when their planets orbit across the stellar disk, producing a small eclipse. The method of radial velocity consists in revealing the oscillations of stars around the center of mass

» Read more
, , , , ,