At the origin of gamma-ray bursts

in #science7 years ago (edited)

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Gamma-ray bursts are catastrophic events related to the explosion of stars 50 times more massive than our Sun. "If you classify all the explosions in the universe based on their power, the gamma-ray bursts come immediately after the big bang. In a couple of seconds, the process can emit as much energy as a star the size of our Sun throughout its life", explains Eleonora Troja, of NASA's Goddard Space Flight Center and co-author of the study.

Because they have a very short duration, from a few milliseconds to a minute, their study is extremely difficult. However, on June 25, 2016, a gamma-ray burst, called GRB160625B, was observed with numerous telescopes, including the Fermi Gamma-ray Space Telescope from NASA, the Russian MASTER-IAC robotized telescope hosted by the Teide Observatory in the Canary Islands. Australia Telescope Compact Array, and the Very Large Array in New Mexico.

The collected data indicate that the flash begins with the sudden development of an extremely intense magnetic field; but as the energy jets grow, the magnetic field fades, and its place is taken by the emission of matter, according to a scheme that unifies two hypotheses that were previously considered alternatives.

The research has also clarified what is the mechanism that feeds the extremely bright initial phase of the lightning, known as the "prompt" phase. So far, three hypotheses have been advanced: black body radiation, which derives from the emission of heat from an object, the so-called reverse Compton effect, which occurs when an extremely energetic particle transfers its energy to a photon, and synchrotron radiation, which occurs when the electrons are accelerated in a curved or spiral path.

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Now here is the power of a GRB
Normally the frequency of this radiation is greater than 10^20 Hz, therefore it has an energy over 100 keV and a wavelength less than 3x10^-13 m, much lower than the diameter of an atom.

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interessante la roba correlata all'universo :)

Hi, I found some acronyms/abbreviations in this post. This is how they expand:

AcronymExplanation
GRBGamma-Ray Burst
IACInternational Astronautical Congress, annual meeting of IAF members,In-Air Capture of space-flown hardware
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