All Topics  
Cosmic ray spallation

 

 
   Email Print
   Bookmark   Link
 

 

Cosmic ray spallation
 
 
  Topics Cosmic ray spallation Topic Home

Cosmic ray spallation is a form of naturally occurring nuclear fission
Nuclear fission

In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the atomic nucleus of an atom splits into smaller parts, often producing free neutrons and lighter atomic nucleus, which may eventually produce photons ....
 and nucleosynthesis
Nucleosynthesis

Nucleosynthesis is the process of creating new atomic nuclei from preexisting nucleons . It is thought that the primordial nucleons themselves were formed from the quark-gluon plasma from the Big Bang as it cooled below ten million degrees....
. It refers to the formation of elements
Chemical element

A chemical element is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its atomic nucleus. The term is also used to refer to a pure chemical Chemical substance composed of atoms with the same number of protons....
 from the impact of cosmic rays on an object. Cosmic rays are highly energetic charged particles
Subatomic particle

A subatomic particle is an elementary particle or composite particle particle smaller than an atom. Particle physics and nuclear physics are concerned with the study of these particles, their interactions, and non-atomic QCD matter....
  from outside of Earth
Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
 ranging from stray electrons to alpha particles . These cause spallation
Spallation

In general, spallation is a process in which fragments of material are ejected from a body due to impact or stress. In nuclear physics, it is the process in which a heavy nucleus emits a large number of nucleons as a result of being hit by a high-energy Elementary_particle, thus greatly reducing its atomic weight....
 when a cosmic ray (e.g. a proton
Proton

The proton is a subatomic particle with an electric charge of +1 elementary charge. It is found in the nucleus of each atom but is also stable by itself and has a second identity as the hydrogen ion, H+....
) impacts with matter
Matter

In common usage, matter is anything that has both mass and volume . A more rigorous definition is used in science: matter is what atoms and molecules are made of....
, including other cosmic rays. The result of the collision is the expulsion of large members of nucleons (protons and neutrons) from the object hit.






Discussion
Ask a question about 'Cosmic ray spallation'
Start a new discussion about 'Cosmic ray spallation'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Cosmic ray spallation is a form of naturally occurring nuclear fission
Nuclear fission

In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the atomic nucleus of an atom splits into smaller parts, often producing free neutrons and lighter atomic nucleus, which may eventually produce photons ....
 and nucleosynthesis
Nucleosynthesis

Nucleosynthesis is the process of creating new atomic nuclei from preexisting nucleons . It is thought that the primordial nucleons themselves were formed from the quark-gluon plasma from the Big Bang as it cooled below ten million degrees....
. It refers to the formation of elements
Chemical element

A chemical element is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its atomic nucleus. The term is also used to refer to a pure chemical Chemical substance composed of atoms with the same number of protons....
 from the impact of cosmic rays on an object. Cosmic rays are highly energetic charged particles
Subatomic particle

A subatomic particle is an elementary particle or composite particle particle smaller than an atom. Particle physics and nuclear physics are concerned with the study of these particles, their interactions, and non-atomic QCD matter....
  from outside of Earth
Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
 ranging from stray electrons to alpha particles . These cause spallation
Spallation

In general, spallation is a process in which fragments of material are ejected from a body due to impact or stress. In nuclear physics, it is the process in which a heavy nucleus emits a large number of nucleons as a result of being hit by a high-energy Elementary_particle, thus greatly reducing its atomic weight....
 when a cosmic ray (e.g. a proton
Proton

The proton is a subatomic particle with an electric charge of +1 elementary charge. It is found in the nucleus of each atom but is also stable by itself and has a second identity as the hydrogen ion, H+....
) impacts with matter
Matter

In common usage, matter is anything that has both mass and volume . A more rigorous definition is used in science: matter is what atoms and molecules are made of....
, including other cosmic rays. The result of the collision is the expulsion of large members of nucleons (protons and neutrons) from the object hit. This process goes on not only in deep space, but in our upper atmosphere due to the impact of cosmic rays.

Cosmic ray spallation produces some light elements such as lithium
Lithium

Lithium is a chemical element with the symbol Li and atomic number 3. It is a soft alkali metal with a silver-white color. Under standard conditions for temperature and pressure, it is the lightest metal and the least dense solid element....
 and boron
Boron

Boron is a chemical element with atomic number 5 and the chemical symbol B. Boron is a trivalent metalloid element which occurs abundantly in the evaporite ores borax and ulexite....
. This process was discovered somewhat by accident during the 1970s. Models of big bang nucleosynthesis
Big Bang nucleosynthesis

In physical cosmology, Big Bang nucleosynthesis refers to the production of nuclei other than those of H-1 during the early phases of the universe....
 suggested that the amount of deuterium
Deuterium

Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen ....
 was too large to be consistent with the expansion rate of the universe and there was therefore great interest in processes that could generate deuterium
Deuterium

Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen ....
 after the big bang.

Cosmic ray spallation was investigated as a possible process to generate deuterium. As it turned out, spallation could not generate much deuterium, and the excess deuterium in the universe could be explained by assuming the existence of non-baryonic dark matter
Dark matter

In astronomy and physical cosmology, dark matter is Hypothesis matter that is undetectable by its emitted electromagnetic radiation, but whose presence can be inferred from gravity effects on visible matter....
. However, studies of spallation showed that it could generate lithium and boron. Isotopes of aluminum, beryllium
Beryllium

Beryllium is a chemical element with the symbol Be and atomic number 4.A Bivalent element, beryllium is found naturally only combined with other elements in minerals....
, carbon
Carbon

Carbon is a chemical element with chemical symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalence?making four electrons available to form covalent bond chemical bonds....
 (carbon-14
Carbon-14

Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California, though its existence had been suggested already in 1934 by Franz Kurie....
), chlorine
Chlorine

Chlorine...
, iodine
Iodine

Iodine , is a chemical element that has the symbol I and atomic number 53. Naturally-occurring iodine is a single isotope with 74 neutrons....
 and neon
Neon

Neon is the chemical element that has the symbol Ne and atomic number 10. Although a very common element in the universe, it is rare on Earth....
, are also formed through cosmic ray spallation.

See also


  • Astrophysics
    Astrophysics

    Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties of astronomical objects such as galaxy, stars, planets, exoplanets, and the interstellar medium, as well as their interactions....
  • Cosmic rays
  • Nuclear fission
    Nuclear fission

    In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the atomic nucleus of an atom splits into smaller parts, often producing free neutrons and lighter atomic nucleus, which may eventually produce photons ....
  • Nucleosynthesis
    Nucleosynthesis

    Nucleosynthesis is the process of creating new atomic nuclei from preexisting nucleons . It is thought that the primordial nucleons themselves were formed from the quark-gluon plasma from the Big Bang as it cooled below ten million degrees....
  • Spall
    Spall

    Spall are flakes of a material that are broken off a larger solid body and can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure ....
    , or spalling
  • Spallation
    Spallation

    In general, spallation is a process in which fragments of material are ejected from a body due to impact or stress. In nuclear physics, it is the process in which a heavy nucleus emits a large number of nucleons as a result of being hit by a high-energy Elementary_particle, thus greatly reducing its atomic weight....
  • Spallation Neutron Source
    Spallation Neutron Source

    The Spallation Neutron Source is an accelerator-based neutron source being built in Oak Ridge, Tennessee , USA, at the site of Oak Ridge National Laboratory by the United States Department of Energy ....
  • ISIS neutron source
    ISIS neutron source

    ISIS is a world leading pulsed neutron and muon source. It is situated at the Rutherford Appleton Laboratory in Oxfordshire, United Kingdom and is part of the Science and Technology Facilities Council ....
  • PSI Spallation Neutron Source (SINQ)
    Paul Scherrer Institute

    The Paul Scherrer Institute is a multi-disciplinary research institute which belongs to the Swiss ETH-Komplex covering also the ETH Zurich and EPFL....


External links