Oh-my-god-particles

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The Oh-My-God-Particle ( borrowed from the English Oh-My-God particle ; also called OMG-Particle or OMG-Particle for short ) is a high-energy particle of cosmic rays (probably a proton ) that was released on October 15th Observed over the US state of Utah in 1991. It had an energy of 320 ± 93 EeV = 3.2 ± 0.93 x 10 20  eV ≈ 51.27 J . This corresponds to the kinetic energy of a golf ball at around 170 km / h . For comparison: normal particles of cosmic rays have energies between 10  MeV and 10 GeV. The detector used was the University of Utah 's Fly's Eye II , which is at 40 ° N, 113 ° W. This detector, built like a fly's eye, searches the night sky on moonless nights for the blue flashes of nitrogen fluorescence, which are caused by particles of cosmic rays when they hit nitrogen molecules.

description

In general, when cosmic rays collide with particles of the earth's atmosphere, only a small part of the energy is available for transformations, because because of the conservation of momentum, most of it is taken over as kinetic energy of the transformation products (see focus energy ). A transformation from the laboratory system to the center of gravity system results in a collision  energy of still around 10 15 eV for the Oh-My-God particle , around a hundred times the energy that is achieved in proton-proton collisions at the LHC (13 · 10 12  eV) .

After this about 15 other, similar observations of such high-energy particles were made with the help of this detector.

origin

Particles with extremely high kinetic energy can only travel a limited distance in space due to the GZK cutoff , an effect of their interaction with radiation, in particular the cosmic microwave background . The observed kinetic energy is assumed to be a maximum of 50 megaparsecs ( Mpc ), i.e. approx. 165 million light years. The region of origin is therefore limited. Radio galaxies , Seyfert galaxies and quasars are candidates for generating such high-energy particles , but such objects are all much further away than 50 Mpc in the region of origin.

The area of ​​origin is right ascension α = 5h 40m 48s ± 0h 2m, declination δ = 48 ° ± 6 °.

Web links

Individual evidence

  1. ↑ Oh My God: On the trail of mysterious particles from space - Heise , July 15, 2018
  2. ^ The Oh-My-God Particle (English) - fourmilab.ch , January 4, 1994
  3. ↑ The Fly's Eye Extremely High Energy Cosmic Ray Spectrum (English; PDF , ≈ 30 KB) - probably published (first) or (re) uploaded on May 11, 2012 (see also associated directory ) ; 4 pages in total (pages 34 to 37)
  4. ↑ In Search for a Source for the 320 EeV Fly's Eye Cosmic Ray (English; PS , ≈ 417 KB) - probably published (first) or (re) uploaded on June 26, 2007 (see also associated directory ) ; 39 pages in total