Category: Ricerca

The XUV emission of the star HIP67522 and the evolution of its exoplanet. The study: “XUV irradiation of young planetary atmospheres. Results from a joint XMM-Newton and HST observation of HIP67522” of A. Maggio (INAF-OAPA) appeared on A&A

Ricerca

Despite the wide array of telescopes and satellites available to the astronomical community, there is a type of radiation to which we are virtually blind: the extreme UV band. This is high-energy radiation with a wavelength that ranges from the Lyman-α emission, caused by hydrogen atoms whose electron transitions from the innermost orbital (the ground state) to the second (n=2),

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Sub-neptunian planets and photoevaporation for BD+40 2790. The study: “The GAPS Programme at TNG. LIX: A characterisation study of the ∼300 Myr old multi-planetary system orbiting the star BD+40 2790 (TOI-2076)” of M. Damasso (INAF – OATo) appeared on A&A

Ricerca

The study of exoplanetary systems of stars with an age of a few hundred million years can teach us a great deal about the early and crucial evolutionary phases of planetary systems. Processes such as planetary migration, which causes planets to modify their distance from the central star, the circularization of orbits, and planetary photoevaporation play a fundamental role in

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The acceleration of cosmic rays in supernova remnants depends on the interaction with the surrounding medium. The study: “Time evolution of the synchrotron X-ray emission in Kepler’s SNR: the effects of turbulence and shock velocity” of V. Sapienza (UNIPA/INAF-OAPA) appeared on ApJ

Ricerca

The role of supernova remnants (expanding clouds produced by supernovae) in the acceleration of cosmic rays (high-energy particles present in various astrophysical environments) has been known since 1995. The discovery, made by astronomers from Kyoto University, was made possible by identifying the presence of non-thermal X-ray emission in the supernova remnant SN 1006. X-rays are a type of high-energy radiation

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X-ray analysis of the Wolf Rayet of Westerlund 1. The study: “EWOCS-II: X-ray properties of the Wolf-Rayet stars in the young Galactic super star cluster Westerlund 1” of K. Anastasopoulou (INAF-OAPA/CfA) appeared on A&A

Ricerca

Massive stars live short and violent lives. Mainly during the later stages of their evolution, these stars undergo significant changes in their structure and lose a large fraction of their initial mass into the surrounding environment as stellar winds. In particular, during the Wolf-Rayet phase, which lasts only a few hundred thousand years, massive stars eject their outer layers, which

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New Study on Thermalization of X-IFU Instrument’s Ultra-Thin Al-Coated Filters led by N. Montinaro (INAF – OAPA)

Ricerca

X-ray astronomy is aimed at the understanding of the high-energy phenomena occurring in the Universe. Since our atmosphere blocks the X-ray photons, this branch of astronomy relies on observations made with satellites. In the past 30 years, X-ray astronomical observations had two main actors: the NASA satellite Chandra and XMM/Newton of the European Space Agency (ESA). The future, instead, goes

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Ammonia and water in the atmosphere of the warm Neptune HAT-P-11 b. The study described in the paper: “The GAPS Programme at TNG LV. Multiple molecular species in the atmosphere of HAT-P-11 b and review of the HAT-P-11 planetary system” of M. Basilicata (Università di Tor Vergata)

Ricerca

One of the most interesting possibilities offered by the research on exoplanets is the ability to study types of planets that are not present in the Solar System. Among these are the “hot” and “warm” Neptunes. These are planets the size of Neptune that orbit very close to their stars (with an orbital period shorter than 10 days), with an

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Fifteen spectral indices to select planetary-mass objects. The study: “Spectral characterization of young LT dwarfs” of L. Piscarreta (CENTRA, ESO) appeared on A&A

Ricerca

Understanding the star formation process also means acquiring a full understanding of its final products, such as the mass distribution of the stars formed in a single star-formation event (which is the initial mass function). In particular, it is still not clear what the dominant mechanism responsible for the formation of the less massive sources is: the planetary-mass objects, with

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A study on the processes responsible for the acceleration of particles in shocks. The study: “Individual particle approach to the diffusive shock acceleration. Effect of the non-uniform flow velocity downstream of the shock” of O. Petruk (INAF-OAPA) appeared on A&A

Ricerca

Our planet is constantly bombarded by highly energetic particles known as ‘cosmic rays‘. The spectrum of cosmic rays up to energies of 1015 electronvolts (eV) is formed by the sources in our Galaxy, while particles with observed energies up to 1021 eV should have extra-galactic origin. The cosmic ray spectrum follows a power law, meaning that the flux of particles with a given

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Four planets (at least) for two stars. The study: “The GAPS Programme at TNG. LIII. New insights on the peculiar XO-2 system” of A. Ruggieri (Università di Padova) appeared on A&A

Ricerca

Every sci-fi enthusiast, especially Star Wars fans, has wondered whether planets orbiting two stars, like Tatooine, can exist in reality. This is actually an important question in astronomy: It has been estimated that in the Milky Way, one-third of low-mass stars are in binary systems. Therefore, to fully understand the population of planets in our Galaxy, it is necessary to

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Water or stellar activity? The study: “A reanalysis of the LHS 1140 b atmosphere observed with the Hubble Space Telescope” of A. Biagini (INAF-OAPA/UNIPA) appeared on MNRAS

Ricerca

To date, April 1st 2024, 74.4% of the 5602 confirmed exoplanets have been discovered through transit observations. This technique involves observing the imperceptible and periodic dimming of the luminosity of the central star during each transit of their planets in front of the star with respect to our line of sight. Furthermore, by comparing spectroscopic observations of the star outside

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