(ORDO NEWS) — The light turns on, the light turns off – this is how you can describe the behavior of a new star, called RS Ophiuchi (RS Oph).
Approximately every 15 years, a dramatic explosion occurs in the constellation of Ophiuchus. The birthplace of a new star is a system in which two very different stars live in a parasitic relationship: A white dwarf, a small, burned-out and very dense star – a teaspoon of its matter weighs about 1 ton – revolves around a red giant, an old star that will soon burn out .
A dying giant star feeds matter to the white dwarf by shedding its outer hydrogen layer, and the gas flows onto the neighboring white dwarf. This flow of matter continues until the white dwarf eats itself.
The temperature and pressure in the newly recruited stellar shells become too high, and they are ejected as a result of a giant thermonuclear explosion. The dwarf star remains intact and the cycle begins again – until the spectacle repeats itself.
Explosion in the high energy range
It was assumed that such explosions are associated with high energies. Two MAGIC telescopes detected gamma rays of 250 gigaelectronvolts (GeV), one of the highest energies ever measured in neoplasms. For comparison, this radiation is a hundred billion times more energetic than visible light.
MAGIC was able to make its observations after the first signals from other instruments measuring at different wavelengths.
“The spectacular eruption of RS Ophiuchi shows that MAGIC’s fast response really pays off: It takes them no more than 30 seconds to move to a new target,” said David Green, a scientist at the Max Planck Institute for Physics and one of the authors of the Nature paper. Astronomy.
Accelerated protons in cosmic rays
After the explosion, several shock fronts spread through the stellar wind from the red giant into the interstellar medium surrounding the binary system.
These shock waves work like a giant power plant, in which particles are accelerated to speeds close to the speed of light. The combined measurements suggest that gamma rays come from energetic protons, the nuclei of hydrogen atoms.
“It also makes the outbursts of new stars a source of cosmic rays,” explains David Green. “However, as a rule, they play the role of local heroes, that is, they contribute to cosmic rays only in the immediate environment.
Large players in cosmic rays are the remnants of supernovae. The shock fronts that occur during star explosions are much more powerful than those of new stars” .
To fully understand the complex interaction of violent events with the interstellar medium in the Milky Way, more observations like those reported now are needed. Therefore, the MAGIC collaboration will continue to search for “restless” objects in our Galaxy and beyond.
—
Online:
Contact us: [email protected]
Our Standards, Terms of Use: Standard Terms And Conditions.