Cosmic-ray observatory

Cosmic-ray observatory
Shower detection.png

A cosmic-ray observatory is a scientific installation built to detect high-energy-particles coming from space called cosmic rays. This typically includes photons (high-energy light), electrons, protons, and some heavier nuclei, as well as antimatter particles. About 90% of cosmic rays are protons, 9% are alpha particles, and the rest are other particles including but not limited to lithium, beryllium and boron.[1] About .01% of incoming cosmic rays are made of antimatter.[2]

It is not yet possible to build image forming optics for cosmic rays, like a Wolter telescope for lower energy X-rays,[3][4] although some cosmic-ray observatories also look for high energy gamma rays and x-rays. Ultra-high-energy cosmic rays (UHEC) pose further detection problems. One way of learning about cosmic rays is using different detectors to observe aspects of a cosmic ray air shower.

Contents

Gamma-ray detection

Methods of detection for Gamma-rays.[5]

  • Scintillation Detectors
  • Solid State Detectors
  • Compton Scattering
  • Pair Telescopes
  • Air Cerenkov Detectors

For example, while a visible light photon may have an energy of a few eV, a cosmic gamma ray may exceed a TeV (1,000,000,000,000 eV).[5] Sometimes cosmic gamma rays (photons) are not grouped with nuclei cosmic rays.[5]

History

The Explorer 1 satellite launched in 1958 measured cosmic rays.[6] Anton 314 omnidirectional Geiger-Müller tube, designed by Dr. George Ludwig of Iowa's Cosmic Ray Laboratory, detected cosmic rays. It could detect protons with E > 30 MeV and electrons with E > 3 MeV. Most of the time the instrument was saturated;[7]

Sometimes the instrumentation would report the expected cosmic ray count (approximately thirty counts per second) but sometimes it would show a peculiar zero counts per second. The University of Iowa (under Van Allen) noted that all of the zero counts per second reports were from an altitude of 2,000+ km (1,250+ miles) over South America, while passes at 500 km (310 mi) would show the expected level of cosmic rays. Later, after Explorer 3, it was concluded that the original Geiger counter had been overwhelmed ("saturated") by strong radiation coming from a belt of charged particles trapped in space by the Earth's magnetic field. This belt of charged particles is now known as the Van Allen radiation belt.[8]

Cosmic rays were studied aboard the space station Mir in the late 20th century, such as with the SilEye experiment.[9] This studied the relationship between flashes seen by astronauts in space and cosmic rays, the cosmic ray visual phenomena.[9]

Observatories and experiments

There are a number of cosmic ray research initiatives. These include, but are not limited to:

Ultra high energy cosmic rays

Observatories for ultra-high-energy cosmic rays:

See also

References

Further reading

External links


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Monopole, Astrophysics and Cosmic Ray Observatory — MACRO, or the Monopole, Astrophysics and Cosmic Ray Observatory, is a particle physics experiment located at the Laboratori Nazionali del Gran Sasso in Abruzzo, Italy. A number of universities contributed personnel and equipment, including Boston …   Wikipedia

  • Cosmic ray — For the film, see Cosmic Ray (film). Cosmic radiation redirects here. For some background types of cosmic radiation, see cosmic background radiation and cosmic background. The energy spectrum for cosmic rays Cosmic rays are energetic charged… …   Wikipedia

  • Ultra-high-energy cosmic ray — Unsolved problems in physics Why is it that some cosmic rays appear to possess energies that are theoretically too high? In high energy physics, an ultra high energy cosmic ray (UHECR) or extreme energy cosmic ray (EECR) is a cosmic ray with an… …   Wikipedia

  • High Resolution Fly's Eye Cosmic Ray Detector — The High Resolution Fly s Eye or HiRes detector was an ultra high energy cosmic ray observatory that operated in the western Utah desert from May 1997 until April 2006. HiRes utilized the atmospheric fluorescence technique that was pioneered by… …   Wikipedia

  • Compton Gamma Ray Observatory — General information NSSDC ID 1991 027B Organization NASA …   Wikipedia

  • International X-ray Observatory — The International X ray Observatory (IXO) est un observatoire spatial à rayons X qui doit être développé par la NASA, l Agence spatiale européenne et la JAXA (agence spatiale japonaise). Il est prévu que IXO soit lancé en 2021. IXO doit remplacer …   Wikipédia en Français

  • Institute for Cosmic Ray Research — The Institute for Cosmic Ray Research (ICRR) of the University of Tokyo (東京大学宇宙線研究所 Tōkyōdaigaku Uchūsen Kenkyūjo ) was established in 1976 for the study of cosmic rays. [ [http://www.icrr.u tokyo.ac.jp/intro/intro e.html ICRR / About ICRR ] ]… …   Wikipedia

  • International X-ray Observatory — Эта статья или часть статьи содержит информацию об ожидаемых событиях. Здесь описываются события, которые ещё не произошли …   Википедия

  • Extragalactic cosmic ray — Extragalactic cosmic rays are very high energy particles that flow into our solar system from beyond our galaxy. The energies these particles possess are in excess of 1015 eV. Origin Unlike solar or galactic cosmic rays, little is known about the …   Wikipedia

  • Compton Gamma-Ray Observatory — Vue d artiste du Compton Gamma Ray Observatory Caractéristiques Organisation NASA …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”