Magnetic alpha spectrometer ( Eng. Alpha Magnetic Spectrometer , AMS) is a physical device designed to study the composition of cosmic rays , search for antimatter and dark matter [1] . The first version of such an instrument ( AMS-01 ) was installed on the Shuttle Discovery , which visited the Mir orbital station in 1998 as part of the STS-91 mission. AMS-01 registered about one million helium nuclei and confirmed the operability of the concept, which made it possible to create a new improved version of the device. The second version ( AMS-02 ) was launched on May 16, 2011 [2] as part of the STS-134 mission, and on May 19 it was installed on the ISS [3] . The operation of the device will last 3 years, [4] for which it must register about one billion helium and other nuclei. The main researcher of the project is the Nobel laureate Samuel Ting . The cost of the device is estimated at 2 billion US dollars [5] .
Content
AMS Objective
Testing the fundamental hypotheses of the structure of matter and the origin of the universe .
Description
Magnetic Alpha Spectrometer (AMS-02) is the most advanced physical particle detector . Built and tested by an international team of scientists from 16 countries. The project is sponsored by the US Department of Energy . AMS-02 is designed to lead humanity to an understanding of the origin of the universe . It is planned to study cosmic radiation and prove the existence of antimatter and dark matter.
On AMS-02, a permanent magnet is installed instead of superconducting on liquid helium . Due to this, the service life of the device is at least 15 years.
Experimental data show that our galaxy is made up of matter . There are more than 100 billion galaxies in the universe. The Big Bang Theory assumes an equal amount of matter and antimatter. But theories that explain this apparent asymmetry contradict experimental data. The existence of antimatter is one of the fundamental questions of the origin and nature of the universe . Any observations of antihelium nuclei will be evidence of the existence of antimatter. In 1998, AMS-01 set an upper limit on the ratio of antihelium and helium in cosmic radiation: 10 −6 . The sensitivity of AMS-02 is 10 −9 . Increasing this value by three orders of magnitude is enough to reach the edge of the expanding Universe, which will solve the problem completely.
Visible matter, mainly consisting of stars , makes up no more than 5% of the total observed mass of the Universe. The remaining 95% is dark matter, the mass of which is estimated at 20% of the mass of the Universe, and dark energy , which determines the balance. Their exact nature is still not known. One of the leading hypotheses is that dark matter is neutralino . If neutralinos exist, they must collide with each other, resulting in the creation of charged particles that AMS-02 detects. Any peak in the background positron -, antiproton -, or gamma- streams can indicate the presence of neutralino.
Six types of quarks (u, d, s, c, b, and t) were discovered experimentally , but all life on Earth consists of two types of quarks (u and d). This is another fundamental question - is there matter consisting of three types of quarks (u, d and s)? The hypothetical particle of this matter, the staple , can have an extremely large mass and a very small charge to mass ratio. This is a completely new form of matter. AMS-02 will give a definitive answer to the question of the existence of this matter.
Cosmic radiation is a significant obstacle to manned flights to Mars . Accurate measurements of cosmic radiation are necessary to plan appropriate protective measures. Most cosmic radiation studies have been done by balloon satellites, whose flight time is measured in days; the results of these studies were very inaccurate. AMS-02 will work on the ISS for 3 years, collecting a huge amount of accurate data. This will allow you to measure long-term changes in the flux of cosmic rays in a wide range of energies, for particles from protons to iron nuclei. After a nominal mission, AMS-02 can continue to measure. In addition to the knowledge about radiation protection needed for manned interplanetary flights, this data will allow you to learn all about the interstellar propagation and origin of cosmic radiation.
Results obtained
The first results of a magnetic alpha spectrometer were published in early April 2013. Project leader Samuel Ting at the CERN seminar said that they managed to detect an increase in the proportion of positrons in cosmic rays with an increase in their energy: if for particles with an energy of 10 GeV, the proportion of positrons was about 5%, then for particles with an energy of 350 GeV - more than 15%. This became an independent confirmation of the results obtained earlier by the PAMELA experiment (published in April 2009) and the Fermi telescope (published in January 2012). A possible explanation for this effect may be the emission of pulsars or the annihilation of hypothetical particles of dark matter , WIMPs [5] [6] .
Notes
- ↑ Alpha Magnetic Spectrometer - 02 (AMS-02) on the NASA website (inaccessible link) . Date of treatment August 16, 2009. Archived August 16, 2009.
- ↑ STS-134 BRIEFING AND EVENTS SCHEDULE
- ↑ AT HOME, AT LAST . AMS collaboration (May 19, 2011). Date of treatment August 22, 2011. Archived March 16, 2012.
- ↑ AMS experiment mission overview (link unavailable) . Date of treatment September 3, 2009. Archived March 17, 2012.
- ↑ 1 2 Adrian Cho . Two Billion Dollar Cosmic Ray Detector Confirms Possible Signs of Dark Matter (Eng.) , Science NOW (April 3, 2013). Archived on April 6, 2013. Date of treatment April 3, 2013.
- ↑ The first results of the AMS-02 experiment are interesting, but did not bring sensations
Links
- Official site AMS-02 (inaccessible link) . Date of treatment April 24, 2011. Archived on April 18, 2012.
- STS-134 mission animated film showing the installation of AMS-02 (72MB)
- 2011 Missions: Magnetic Alpha Spectrometer