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Cosmic rays are high-energy particles in space that is thought to have come from the remains of dead stars. However, IceCube detects that the particles arrive not in a "uniform" from all directions. Recent research suggests that galactic cosmic rays may change the Earth's climate, affecting weather, triggering a storm and cloud cover. As reported Livescience.com, edition July 30, 2010, the study showed that the excess of cosmic rays coming from one part of the sky, and cosmic rays are less levels come from other parts.
ENERGY SPECTRUM FOR COSMIC RAYS
Energy cosmic rays are charged subatomic particles, originating in outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. Long beam is historical as cosmic rays are considered to electromagnetic radiation. The most primary cosmic rays (those that enter the atmosphere from space inside) consists of unstable subatomic particles familiar that usually occurs on Earth, such as protons, nuclei, or electrons. However, a small portion is stable antimatter particles, such as positron or antiproton, and the exact nature of the fraction that remains is an area of active research. Approximately 89% of cosmic rays simple proton or nucleus of hydrogen, 10% are helium nuclei or alpha particles, and 1% are the core of heavy elements. This core is 99% of cosmic rays. Lone (such as beta particles, although their main source unknown) is more than 1% is left.
Various particle energies reflects a variety of sources. The range of the origin of the processes in the Sun (and possibly other stars), for as yet unknown physical mechanisms in the farthest observable universe. There is evidence that cosmic rays are very high energy produced over a period far longer than the explosion of a single star or galaxy sudden event, showing some acceleration process that covers great distances in terms of the size of the star. No clear mechanism of production of cosmic rays at a distance of galaxies is partly the result of the fact that (unlike other radiation) in the magnetic field of our galaxy and other galaxies bends toward cosmic rays seriously, so that they arrive almost at random from all directions, to hide any hint of the direction their initial source. Cosmic rays can have energies more than 1020 eV, is much higher than that from 1012 to 1013 eV Terrestrial particle accelerators can produce.
Cosmic rays are enriched with lithium, beryllium, and boron related to the relative abundance of the elements in the universe than the hydrogen and helium, and thus are considered to have a major role in the synthesis of these three elements through the process of 'nucleosynthesis cosmic rays ". They also produce some called cosmogenic radioisotopes and stable isotopes on Earth, such as carbon-14. In the history of particle physics, the discovery of cosmic rays is a source of positrons, muons, and pi mesons.
Cosmic rays to write part of the natural background radiation in the Earth, on average, about 10-15% of it. However, people who live at higher altitudes can earn several times more cosmic radiation than the sea surface, and a long-distance flight crews can double their annual exposure to ionizing radiation. Because of the intensity of cosmic rays is much greater outside the Earth's atmosphere and magnetic field, is expected to have a major impact on the design of spacecraft that can safely transporting humans in interplanetary space.
COMPOSITION OF COSMIC RAYS
Cosmic rays can be broadly divided into two categories: primary and secondary. Cosmic rays coming from astrophysical sources is the primary cosmic rays. The primary cosmic rays interact with interstellar matter creating secondary cosmic rays. The sun also emits low energy cosmic rays associated with solar flares. Almost 90% of cosmic rays of protons, about 9% are helium nuclei (alpha particles) and nearly 1% are electrons. The ratio of hydrogen to helium nucleus (28%) is the same as the primordial element abundance ratios of these elements (24%). The remaining fraction consisting of heavy nuclei other end products of nuclear synthesis, the product of the Big Bang, especially lithium, beryllium, and boron.Ini light nuclei appear in cosmic rays in much greater abundance (~ 1%) than in the solar atmosphere, where their abundance is about 10-9% that helium.
Differences in abundance is the result of the way secondary cosmic rays are formed. Carbon and oxygen nucleus collides with interstellar matter to form lithium, beryllium and boron in a process called spallation cosmic rays. Spallation is also responsible for the amount of ions scandium, titanium, vanadium, and manganese in the cosmic rays produced by collisions of iron and nickel core with interstellar matter.
Satellite experiments have found evidence of some antiprotons and positrons in cosmic rays primary, although there is no evidence of antimatter nuclei complexes, such as anti-helium nucleus (anti-alpha) particles. Antiproton arrives on Earth with a maximum energy of 2 GeV characteristics, showing their production process differs fundamentally from cosmic ray protons.
FLOW COSMIC RAYS
The flux of cosmic rays that enter the upper atmosphere depends on the solar wind, the Earth's magnetic field, and the energy of cosmic rays. Decelerates solar wind particles that enter and block some particles with energies below about 1 GeV. Total solar wind is not constant due to changes in solar activity. Thus, the rate of cosmic ray flux varies with solar activity. Earth's magnetic field divert some of the cosmic rays, giving rise to the observation that this flux is apparently dependent on latitude, longitude, and azimuth angles. The magnetic field lines deflect cosmic rays toward the poles, causing aurora.
At a distance of ~ 94 AU from the Sun, the solar wind in transition, called the termination shock, from supersonic to subsonic speeds. The area between the termination shock and heliopause act as a barrier to cosmic rays, a decrease in the flux of lower energy about 90%.
In the past, it was believed that the cosmic ray flux has remained fairly constant over time. However, recent research suggests 1.5 to 2-fold millennium-timescale changes in the cosmic ray flux forty thousand years. The amount of energy flux of cosmic rays in the interstellar space is very comparable to other energy in the room: the average energy density of cosmic rays around one electron-volts per cubic centimeter of interstellar space, or ~ 1 eV / cm3, which is comparable to the energy density of light Star seen at 0.3 eV / cm3, the magnetic field energy density of galaxies (assumed to be 3 microgauss) which is ~ 0.25 eV / cm3, or the cosmic microwave background (CMB) radiation energy density at ~ 0.25 eV / cm3 ,
However, cosmic rays, unlike other energy components above, consists of ionizing particles, and this is much more destructive biological processes from simple energy suggest. As noted below, cosmic rays make an average of 10 to 15% of background ionizing radiation on humans on Earth, but this component can be several times greater for people who live at higher altitudes.
COSMIC RAYS DETECTION
In the shadow of cosmic rays, as seen in secondary muons detected 700 m below ground, in the Soudan 2 detector Moon as seen by the Compton Gamma Ray Observatory, the gamma rays of greater than 20 MeV. It is produced by cosmic rays shooting from the surface.
Core cosmic rays collide with atmospheric gases, generating rain, among others, pions and kaons, the muon decay. It muons can reach the Earth's surface, and even penetrated for some distance into the shallow mines. Muon easily detected by various types of particle detectors as a cloud chamber or a bubble chamber or scintillation detectors. Muon Some observed by separate detectors at the same time indicates that they have been produced in the same shower event. Cosmic rays impacting the other planetary bodies in the solar system were detected indirectly by observing the emission of high-energy gamma rays to gamma-ray telescope. It is distinguished from the process of radioactive decay by their higher energies above about 10 MeV.
DETECTION OF COSMIC RAYS
Ø particle detection by track-etch technique
Cosmic rays can also be detected directly by the particle detector aboard satellites or high altitude balloons. In a pioneering technique developed by Robert Fleischer, P. Buford Price, and Robert M. Walker, sheets of clear plastic, such as Lexan polycarbonate 1/4 mile, stacked together and directly exposed to cosmic rays in space or core .Muatan plateau causing chemical breaking the bonds or ionization in the upper plastik.Di pile of plastic, less ionization due to high speed cosmic rays. As the speed of cosmic rays decreased due to the slowdown in the stack, the ionization increases along the way. Plastic sheet produced "scratched" or slowly dissolved in warm caustic sodium hydroxide solution, which removes the surface material at a slow rate that dikenal.Para caustic sodium hydroxide dissolved in a faster rate along the path of ionized plastic. The end result is a cone-shaped hole or etch holes in the plastic. Etch hole is measured in a high-power microscope (usually 1600X oil immersion), and the etch rate of plotted as a function of depth in the stacked plastic. It generates a unique curve for each atomic nucleus of Z 1-92, allows the identification of both the cost and energy of cosmic rays passing through vast stacks plastik.Semakin ionization along the road, the higher the cost.
This technique has been used with great success not only to detect cosmic rays, but the core fission products for neutron detectors.
ENERGY SPECTRUM FOR COSMIC RAYS
Energy cosmic rays are charged subatomic particles, originating in outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. Long beam is historical as cosmic rays are considered to electromagnetic radiation. The most primary cosmic rays (those that enter the atmosphere from space inside) consists of unstable subatomic particles familiar that usually occurs on Earth, such as protons, nuclei, or electrons. However, a small portion is stable antimatter particles, such as positron or antiproton, and the exact nature of the fraction that remains is an area of active research. Approximately 89% of cosmic rays simple proton or nucleus of hydrogen, 10% are helium nuclei or alpha particles, and 1% are the core of heavy elements. This core is 99% of cosmic rays. Lone (such as beta particles, although their main source unknown) is more than 1% is left.
Various particle energies reflects a variety of sources. The range of the origin of the processes in the Sun (and possibly other stars), for as yet unknown physical mechanisms in the farthest observable universe. There is evidence that cosmic rays are very high energy produced over a period far longer than the explosion of a single star or galaxy sudden event, showing some acceleration process that covers great distances in terms of the size of the star. No clear mechanism of production of cosmic rays at a distance of galaxies is partly the result of the fact that (unlike other radiation) in the magnetic field of our galaxy and other galaxies bends toward cosmic rays seriously, so that they arrive almost at random from all directions, to hide any hint of the direction their initial source. Cosmic rays can have energies more than 1020 eV, is much higher than that from 1012 to 1013 eV Terrestrial particle accelerators can produce.
Cosmic rays are enriched with lithium, beryllium, and boron related to the relative abundance of the elements in the universe than the hydrogen and helium, and thus are considered to have a major role in the synthesis of these three elements through the process of 'nucleosynthesis cosmic rays ". They also produce some called cosmogenic radioisotopes and stable isotopes on Earth, such as carbon-14. In the history of particle physics, the discovery of cosmic rays is a source of positrons, muons, and pi mesons.
Cosmic rays to write part of the natural background radiation in the Earth, on average, about 10-15% of it. However, people who live at higher altitudes can earn several times more cosmic radiation than the sea surface, and a long-distance flight crews can double their annual exposure to ionizing radiation. Because of the intensity of cosmic rays is much greater outside the Earth's atmosphere and magnetic field, is expected to have a major impact on the design of spacecraft that can safely transporting humans in interplanetary space.
COMPOSITION OF COSMIC RAYS
Cosmic rays can be broadly divided into two categories: primary and secondary. Cosmic rays coming from astrophysical sources is the primary cosmic rays. The primary cosmic rays interact with interstellar matter creating secondary cosmic rays. The sun also emits low energy cosmic rays associated with solar flares. Almost 90% of cosmic rays of protons, about 9% are helium nuclei (alpha particles) and nearly 1% are electrons. The ratio of hydrogen to helium nucleus (28%) is the same as the primordial element abundance ratios of these elements (24%). The remaining fraction consisting of heavy nuclei other end products of nuclear synthesis, the product of the Big Bang, especially lithium, beryllium, and boron.Ini light nuclei appear in cosmic rays in much greater abundance (~ 1%) than in the solar atmosphere, where their abundance is about 10-9% that helium.
Differences in abundance is the result of the way secondary cosmic rays are formed. Carbon and oxygen nucleus collides with interstellar matter to form lithium, beryllium and boron in a process called spallation cosmic rays. Spallation is also responsible for the amount of ions scandium, titanium, vanadium, and manganese in the cosmic rays produced by collisions of iron and nickel core with interstellar matter.
Satellite experiments have found evidence of some antiprotons and positrons in cosmic rays primary, although there is no evidence of antimatter nuclei complexes, such as anti-helium nucleus (anti-alpha) particles. Antiproton arrives on Earth with a maximum energy of 2 GeV characteristics, showing their production process differs fundamentally from cosmic ray protons.
FLOW COSMIC RAYS
The flux of cosmic rays that enter the upper atmosphere depends on the solar wind, the Earth's magnetic field, and the energy of cosmic rays. Decelerates solar wind particles that enter and block some particles with energies below about 1 GeV. Total solar wind is not constant due to changes in solar activity. Thus, the rate of cosmic ray flux varies with solar activity. Earth's magnetic field divert some of the cosmic rays, giving rise to the observation that this flux is apparently dependent on latitude, longitude, and azimuth angles. The magnetic field lines deflect cosmic rays toward the poles, causing aurora.
At a distance of ~ 94 AU from the Sun, the solar wind in transition, called the termination shock, from supersonic to subsonic speeds. The area between the termination shock and heliopause act as a barrier to cosmic rays, a decrease in the flux of lower energy about 90%.
In the past, it was believed that the cosmic ray flux has remained fairly constant over time. However, recent research suggests 1.5 to 2-fold millennium-timescale changes in the cosmic ray flux forty thousand years. The amount of energy flux of cosmic rays in the interstellar space is very comparable to other energy in the room: the average energy density of cosmic rays around one electron-volts per cubic centimeter of interstellar space, or ~ 1 eV / cm3, which is comparable to the energy density of light Star seen at 0.3 eV / cm3, the magnetic field energy density of galaxies (assumed to be 3 microgauss) which is ~ 0.25 eV / cm3, or the cosmic microwave background (CMB) radiation energy density at ~ 0.25 eV / cm3 ,
However, cosmic rays, unlike other energy components above, consists of ionizing particles, and this is much more destructive biological processes from simple energy suggest. As noted below, cosmic rays make an average of 10 to 15% of background ionizing radiation on humans on Earth, but this component can be several times greater for people who live at higher altitudes.
COSMIC RAYS DETECTION
In the shadow of cosmic rays, as seen in secondary muons detected 700 m below ground, in the Soudan 2 detector Moon as seen by the Compton Gamma Ray Observatory, the gamma rays of greater than 20 MeV. It is produced by cosmic rays shooting from the surface.
Core cosmic rays collide with atmospheric gases, generating rain, among others, pions and kaons, the muon decay. It muons can reach the Earth's surface, and even penetrated for some distance into the shallow mines. Muon easily detected by various types of particle detectors as a cloud chamber or a bubble chamber or scintillation detectors. Muon Some observed by separate detectors at the same time indicates that they have been produced in the same shower event. Cosmic rays impacting the other planetary bodies in the solar system were detected indirectly by observing the emission of high-energy gamma rays to gamma-ray telescope. It is distinguished from the process of radioactive decay by their higher energies above about 10 MeV.
DETECTION OF COSMIC RAYS
Ø particle detection by track-etch technique
Cosmic rays can also be detected directly by the particle detector aboard satellites or high altitude balloons. In a pioneering technique developed by Robert Fleischer, P. Buford Price, and Robert M. Walker, sheets of clear plastic, such as Lexan polycarbonate 1/4 mile, stacked together and directly exposed to cosmic rays in space or core .Muatan plateau causing chemical breaking the bonds or ionization in the upper plastik.Di pile of plastic, less ionization due to high speed cosmic rays. As the speed of cosmic rays decreased due to the slowdown in the stack, the ionization increases along the way. Plastic sheet produced "scratched" or slowly dissolved in warm caustic sodium hydroxide solution, which removes the surface material at a slow rate that dikenal.Para caustic sodium hydroxide dissolved in a faster rate along the path of ionized plastic. The end result is a cone-shaped hole or etch holes in the plastic. Etch hole is measured in a high-power microscope (usually 1600X oil immersion), and the etch rate of plotted as a function of depth in the stacked plastic. It generates a unique curve for each atomic nucleus of Z 1-92, allows the identification of both the cost and energy of cosmic rays passing through vast stacks plastik.Semakin ionization along the road, the higher the cost.
This technique has been used with great success not only to detect cosmic rays, but the core fission products for neutron detectors.
nice, info pendidikannya :D
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