Alpha rays
Alpha rays are also known as alpha particle beams, high-speed movement of the nucleus of helium atoms. alpha particles consist of 2 protons and 2 neutrons. It has a rest mass of 6.64*10-27 kg and a charge of 3.20*10-19 ku. He is used in physics to denote the alpha particle or helium nucleus. Rutherford first discovered natural radioactivity as several different kinds of rays. He named the positively charged rays alpha rays; the negatively charged rays beta rays. In a later series of experiments Rutherford and others confirmed that the alpha particle is the helium nucleus.
Beta rays
Beta rays: high-speed movement of the electron stream 0/-1e, through the ability to be very strong, ionization effect is weak, originally there is no left and right in the physical world, but the beta rays have a left and right. Beta particles that is, beta particles, is when the radioactive material undergoes beta decay, the release of high-energy electrons, the speed of which can reach up to 99% of the speed of light. During beta decay, a radioactive nucleus transforms into another nucleus by emitting electrons and neutrinos, and the electrons in the product are called beta particles. In positive beta decay, a proton in the nucleus is transformed into a neutron while releasing a positron, and in "negative beta decay," a neutron in the nucleus is transformed into a proton while releasing an electron, the beta particle.
Gamma rays
Gamma rays, also known as gamma particle flow, is the atomic nucleus energy level leap metamorphosis when the release of rays, is shorter than the wavelength of the electromagnetic wave 0.01 ?. Gamma rays have a very strong penetrating power, the industry can be used to detect injuries or the automatic control of the line. gamma rays of the cell has the power of killing, medical treatment is used to treat tumors. gamma rays were first discovered by the French scientists P.V. Villard, is the next step after α, β, and α-beam, and is also used for the treatment of cancer. Gamma rays were first discovered by French scientist P.V. Velarde, and are the third type of nuclear rays discovered after alpha and beta rays.
Hazards of Gamma Rays
Gamma rays have a strong penetrating ability. When the human body is irradiated by gamma rays, the gamma rays can enter into the human body and ionize with the cells in the body, and the ions produced by ionization can erode complex organic molecules, such as proteins, nucleic acids, and enzymes.
They are the main components of living cell tissues, and once they are destroyed, they can lead to interference with normal chemical processes in the body, which can lead to cell death in severe cases.
Expanded:
First, the principle of generation
Radioactive atomic nuclei in the occurrence of alpha decay, beta decay after the production of new nuclei tend to be in the high-energy level, to the low energy level of the leap, the radiation of γ photons. Atomic nuclear decay and nuclear reactions can produce γ rays. The wavelength of gamma rays is shorter than that of X-rays, so gamma rays have a stronger penetrating ability than X-rays.
Gamma rays are electromagnetic photons with a frequency higher than 1.5 gigahertz. Gamma rays do not have electric charge or static mass, so they have a weaker ionizing ability than alpha and beta particles. Gamma rays are extremely penetrating and have high energy. Gamma rays can be stopped by nuclei with high atomic numbers, such as lead or spent uranium.
Second, the measurement method
Gamma photon is not charged, so it can not be measured by magnetic deflection method of its energy, usually caused by the use of gamma photons indirectly out of the above secondary effects, such as through the measurement of photoelectrons or pairs of positron and negative electrons deduced from the energy. In addition, we can also use γ spectrometer (the use of γ rays and material interaction) to directly measure the energy of γ photons.
By the fluorescent crystal, photomultiplier tubes and electronic instruments composed of scintillation counter is to detect the intensity of γ-rays commonly used instruments.
Google Encyclopedia - Gamma rays
What are gamma rays
α-rays are streams of helium nuclei, β-radiation is streams of electrons γ-rays, electromagnetic waves with a wavelength of less than 0.1 nanometers, are a type of radiation with a higher energy than X-rays. Li Qibin proposed seven areas of astronomical research in this century.
Three of them are related to extraterrestrial energy exploration, one is and dark matter related to dark energy, a quasar with a huge radiant energy, there is a huge source of energy from the river outside the date gamma ray burst. Humans have seen only a few percent of the space material, there are more than ninety percent of the material is dark, humans did not see, which is dark matter.
When it comes to dark matter, humans can easily think of "black holes". Black holes are a type of dark matter.
The gravitational force of a black hole is so great that a satellite launched from the Earth has to reach the first cosmic speed of 7.8 kilometers per second before it can break out of the atmosphere, and it is still impossible to exceed the huge gravitational force of a black hole when it is launched at the speed of light. According to Hawking's theory of black holes, a black hole can be identified based on observations of things around it.
If things around it fall down, then it emits X-rays, creating an X-ray halo, and the black hole can be determined based on observations of the X-rays. If a star is observed to keep rotating around a hollow center, then it can also be assumed that there is a black hole in the middle of its orbit.
The exploration of quasars belongs to the observation of the field of celestial activity. Li Qibin explained that the mystery of quasars is that they radiate more energy per second than the entire Milky Way galaxy of 100 billion stars combined.
Astronomers speculate that there must be a unique method of delivering that energy. The discovery of gamma-ray bursts was dramatic.
People first observed gamma rays to monitor nuclear tests, and when instruments were accidentally pointed in the air, gamma rays from space were detected. This led to the discovery of stars that emit gamma rays, some of them in bursts.
Observations by space probes have shown that gamma-ray bursts are frequent, on average, once a day. Gamma-ray bursts are as energetic as quasars.
Li Qibin optimistic that if you can observe and analyze the source of their energy, may be able to solve the human energy crisis and at the expense of the destruction of the environment, energy exploitation. 2003, the end of the U.S. "Science" magazine, the top ten scientific and technological achievements of the year, the study of cosmic gamma rays were selected among them.
This research has improved the understanding of cosmic gamma-ray bursts and confirmed the link between gamma-ray bursts and supernovae. 65 million years ago, an asteroid that crashed into Earth caused the extinction of the dinosaurs.
However, according to the British magazine New Scientist in 2003, the killer from outer space is not only an asteroid, the latest scientific research shows that as early as 400 million years ago, the Earth has experienced another biological extinction, and the culprit is the Milky Way galaxy stars collapsed after the outbreak of "gamma rays"! In astronomy, gamma ray bursts are called "gamma ray bursts". What is a gamma-ray burst? Where does it come from? Why does it produce so much energy? "A gamma-ray burst is a phenomenon in the universe in which a gamma ray is suddenly enhanced."
Zhao Yongheng, a researcher at the National Astronomical Observatory of the Chinese Academy of Sciences, told reporters that gamma rays are electromagnetic waves with a wavelength of less than 0.1 nanometers, and are a type of radiation with higher energy than X-rays. But most gamma rays are blocked by the Earth's atmosphere, and observations must be made outside the Earth.
During the Cold War, the United States launched a series of military satellites to monitor nuclear explosion tests around the world, and on these satellites were installed gamma-ray detectors to monitor the large amounts of high-energy rays produced by nuclear explosions. Reconnaissance satellites in 1967 detected a sudden increase in gamma rays from the vastness of space over a short period of time, which was called a "gamma ray burst".
Because of military secrecy, the discovery was not publicized until 1973. It is a phenomenon that baffles astronomers: some gamma-ray sources suddenly appear for a few seconds and then disappear.
Such bursts release energy at a very high power. The "brightness" of a single gamma-ray burst is equal to the "brightness" of all the gamma-ray sources throughout the day combined.
Subsequently, gamma-ray bursts are constantly monitored by high-energy astronomical satellites, and are observed once or twice a day. The energy released by gamma-ray bursts can even be compared to the Big Bang.
According to researcher Yongheng Zhao, the duration of gamma-ray bursts is very short, the long ones are usually tens of seconds, and the short ones are only a few tenths of a second. And its brightness changes are also complex and irregular.
But the energy released by gamma-ray bursts is very huge, in a number of seconds the energy of the gamma rays radiated is equivalent to hundreds of the Sun in its lifetime (10 billion years) in the total energy released! In December 14, 1997 the gamma ray burst, it is as far away as 12 billion light years from the Earth, the release of energy than the supernova burst is hundreds of times larger, in 50 seconds the release of gamma rays is equivalent to the entire Milky Way Galaxy 200 years of the total radiation energy. This gamma-ray burst is as bright as the entire universe except for it in a second or two.
Within a few hundred kilometers of it, the high temperatures and high densities of a thousandth of a second after the Big Bang were reproduced. However, the gamma-ray burst that occurred on January 23, 1999, was even more powerful than this one, emitting ten times the energy of the one in 1997, and was the most powerful gamma-ray burst known to mankind to date.
The cause of gamma-ray bursts has been a subject of great debate, and the world has yet to come to a conclusion about their cause. Some people speculate that it is generated when two neutron stars or two black holes collide; others guess that it is generated during the process of generating a black hole in the death of a massive star, but this process is much more violent than the supernova outburst, and therefore, some people also call it a "supernova".
Zhao Yongheng researcher said, in order to explore the causes of gamma-ray bursts, triggered a big debate between two astronomers. In the 1970s and 1980s, it was widely believed that gamma-ray bursts were phenomena occurring within the Milky Way, and it was hypothesized that they were related to physical processes on the surface of neutron stars.
However, Polish-American astronomer Paczynski stood alone. He proposed in the mid-1980s that gamma-ray bursts are objects located at cosmological distances as far away as quasars, effectively saying that they occur outside the Milky Way.
By that time, however, people had already been ruled by the theory that gamma-ray bursts occur within the Milky Way for many years, so they were not convinced by Paczynski's view.
What are gamma rays?
Gamma rays, also known as gamma particle streams, are phonetically translated as gamma rays in Chinese. Electromagnetic waves with wavelengths shorter than 0.2 angstroms [1]. First discovered by the French scientist P.V. Velarde, is following the alpha and beta rays after the discovery of the third kind of atomic nuclear rays. Atomic nuclear decay and nuclear reactions can produce γ-rays. γ-rays have a stronger penetrating ability than X-rays. When γ rays through the material and interact with atoms will produce photoelectric effect, Compton effect and positive and negative electron pairs of three effects. Atomic nucleus released γ photons and nuclear electrons touch, will give all the energy to the electron, so that the electron ionization into photoelectric, this is the photoelectric effect. As the shell layer of electrons outside the nucleus appeared empty space, will produce the inner layer of electrons jump and emit X-ray identification spectrum. High-energy γ photon (>2 mega electron volt) photoelectric effect is weak. γ photon energy is higher, in addition to the above photoelectric effect, but also with the nuclear electrons may be elastic collision, γ photon energy and the direction of the movement have changed, thus producing the Compton effect. When the energy of γ photon is greater than twice the static mass of electrons, due to the role of the nucleus and the transformation into a positive and negative electron pairs, this effect with the increase in the energy of γ photons and enhance the γ photon is not electrically charged, so it can not be measured with the magnetic deflection method of its energy, usually caused by the use of γ photon of the above secondary effects indirectly, such as through the measurement of photoelectrons or positron-negative electron pairs of the energy is deduced. In addition, the energy of γ photon can be measured directly by γ spectrometer (using crystal diffraction of γ rays). A scintillation counter consisting of a fluorescent crystal, a photomultiplier tube and electronics is a common instrument for detecting the intensity of γ-rays.
Through the study of the gamma ray spectrum can understand the energy structure of the nucleus. gamma rays have a strong penetrating power, the industry can be used to detect injuries or the automatic control of the assembly line. gamma rays on the cell has the power to kill, medical treatment is used to treat tumors.
The detection of gamma rays helps in the study of astronomy.
When humans look into space, they see "visible light", but most of the electromagnetic spectrum is composed of different types of radiation, some of which have longer or shorter wavelengths than visible light, and most of which can't be seen with the naked eye alone. Detecting gamma rays can provide images of space that are invisible to the naked eye.
Gamma rays generated in space are produced by nuclear fusion at the core of stars, and because they cannot penetrate the Earth's atmosphere, they cannot reach the Earth's lower atmosphere and can only be detected in space. Gamma rays in space were first observed in 1967 by an artificial satellite called Vilas. Images of gamma rays detected by various satellites from the early 1970s provided information about hundreds of previously undiscovered stars and possible black holes. Artificial satellites launched in the 1990s (including the Compton Gamma Ray Observatory) have provided astronomical information on supernovae, young star clusters, quasars, and much more.
Gamma rays are a strong electromagnetic wave, which has a shorter wavelength than X-rays, and the general wavelength gamma rays have an extremely strong penetrating ability. When the human body is irradiated by gamma rays, gamma rays can enter the body's interior, and with the body cell ionization, ionization of ions can erode complex organic molecules, such as proteins, nucleic acids, and enzymes, which are composed of living cells and tissues of the main components, once they are destroyed, will lead to the normal chemical processes in the body to be interfered with, and serious cell death
What is gamma radiation? What are Gamma Rays
Scientists observed a Gamma Ray Burst (GRB) just after it occurred, witnessing the destruction of a massive star and the birth of what is believed to be a rotating black hole. The observation is the most detailed record of a Gamma Ray Burst to date, and the results are published in the March 20 issue of the journal Nature. Gamma bursts are the most powerful explosions known in the Universe, with a single gamma burst releasing hundreds of times the energy of a supernova explosion, and peaking at 10 billion billion times the brightness of the Sun. Scientists on the observation of gamma bursts show that gamma bursts are very frequent, uniform and randomly distributed in the universe, so scientists believe that gamma bursts are born in the celestial bodies quite far away from us. One of the main reasons scientists are interested in gamma bursts is to know the origin of these powerful explosions, which are now thought to be caused by two black holes or neutron stars colliding with each other, or by massive stars collapsing into black holes as they die. Gamma bursts are very frequent, but it is not easy to observe a gamma burst instantly, because it is unpredictable in terms of location and direction, and the duration is very short, usually gamma bursts of large-scale gamma ray emission lasts only a few seconds or even as short as a few milliseconds. The successful observation was made possible by NASA's High-Energy Transient Explorer (HETE), ground-based robotic telescopes and responsive researchers around the world. The gamma burst, named GRB021004, occurred at 8:06 a.m. EST on October 4, 2002, and was immediately observed by HETE, which notified observers around the world of the event's location and bearing seconds later, while the gamma burst was still in progress. A few minutes later, observers around the world observed the afterglow of the gamma burst. During the observation, scientists found that the afterglow lasted for more than half an hour. This gave scientists a new understanding of the power of gamma bursts. "Gamma bursts must be many times more powerful than we originally thought," said George Ricker of the Massachusetts Institute of Technology. Gamma rays may be just the tip of the iceberg in terms of the energy of a gamma burst," said Dr. George Ricker of the Massachusetts Institute of Technology (MIT). Scientists believe this observation of a gamma burst was created when the core of a star 15 times more massive than the Sun collapsed into a black hole ....
What is a gamma-ray burst?
A gamma ray burst (GRB), also known as a gamma storm, is a sudden increase in the intensity of gamma rays from the sky in one direction for a short period of time, followed by a rapid weakening of the phenomenon, the duration of which is 0.1-1000 seconds, and the radiation is mainly concentrated in the 0.1-100 MeV energy band.
Gamma storms were discovered in 1967, and their nature has not been well understood for decades, but they are basically recognized as an outburst process that occurs in stellar-scale objects on cosmological scales. Gamma storms are currently one of the most active research areas in astronomy, and have twice been named among the top ten scientific and technological advances of the year by the U.S. journal Science, in 1997 and 1999.
Basic Introduction Gamma-ray bursts, or simply "gamma bursts", are sudden increases in gamma rays in the universe. Gamma rays are electromagnetic waves with a wavelength of less than 0.1 nanometers, and are more energetic than X-rays. Gamma ray bursts are very energetic, and the amount of energy they release can be compared to that of the Big Bang, but they are very short-lived, lasting from a few tens of seconds to a few tenths of a second, and their brightness varies in complex and erratic ways.
Gamma-ray bursts (GRBs) can be divided into two distinct types, and astronomers have long suspected that they arise from two different causes. The more common long gamma bursts (lasting anywhere from 2 seconds to a few minutes) have pretty much been explained away.
In the current picture, they are produced when a hot, supermassive Wolf-Rayet star collapses to form a black hole. Although short gamma-ray bursts are fleeting, Rainbird now captures 10 of them per year, providing an invaluable source of information for our research.
Our research now suggests that short gamma-ray bursts may arise from the merger of two stars in a binary system and the simultaneous creation of a black hole. The energy mechanism of gamma-ray bursts is still far from being resolved, and this is the central question in gamma-ray burst research.
As technology advances, mankind's understanding of the universe will be more in-depth, and many of the problems that now seem to be a mystery may be solved in the future, exploring the mysteries of the universe is not only the pursuit of scientific progress is necessary for mankind, these mysteries will be solved will also benefit mankind itself. Causes Astronomers' previous theory: it may be that such gamma-ray bursts are too far away to be observed in the visual wavelength range.
A recent study reveals that interstellar dust absorbs almost all visible light, but higher-energy gamma rays and X-rays penetrate the dust and are captured by telescopes on Earth. Gamma ray bursts Gamma ray bursts However the idea that the death of a massive star produces a gamma burst has been generally accepted.
Astronomers believe that most of these gamma bursts occur when supermassive stars run out of nuclear fuel. When the core of the star collapses into a black hole, jets of material rush outward at nearly the speed of light.
The jet surges past the collapsing star and continues to travel out into cosmic space, where it interacts with gas previously illuminated by the star, producing a bright afterglow that decays with time. Most gamma rays will appear bright in the visible range.
Some gamma-ray bursts, however, are dark, and they are undetectable in optical telescopes. A recent study shows that dark gamma-ray bursts are not actually unobservable due to distance, but rather their inability to emit light is due to absorption of most of the visible light by interstellar dust clusters, which may be the birthplaces of stars.
Once triggered a biological mass extinction 400 million years ago. It may arise from the thunder, but also involved in the formation of lightning drought new research suggests that the gamma and gamma rays released in the thunder may be the main original on the island of lightning * horse rays may be the main reason for the formation of lightning.
This conjecture. Four years ago the Florida Technological Associates cause. Compton Gamma Ray Observatory in the last century will be astrophysicist Joseph Dwyer on the early 1990s from the ground lightning found proposed.
Gamma rays. At that time, Dwyer from some related academic reports gamma rays are wavelengths of less than 0.1 nanometers of electricity found that gamma rays and lightning have a relationship, in order to prove that the magnetic wave, the radiation energy is higher than x-rays.
Gamma shot this relationship, he established a high-energy radiation lines in a short period of time suddenly enhance the formation of ray bursts. The model was used to describe the formation of the electric field in the Earth's atmosphere. Gamma ray bursts are equivalent to the Big Bang in terms of energy release.
The gamma ray results found that these gamma ray bursts in the electric field, the reason for the formation of the storm, in the end, is the release of high-speed electrons from the two neutron stars and other particles in the atmosphere when the collision occurs, or a massive star in the death crash, can produce a powerful thunder. Simultaneously released when the process of generating a black hole produced . So far no charge has come out. In thunderstorms . Upward air currents and down there is definitive.
But there is one thing that scientists have recognized that the descending air currents push water molecules interact with each other. The strength of the electric field that is when there is a huge cosmic energy generated than increases and eventually releases electrons at close to the speed of light as in the process of generating thunderstorms. Gamma rays are produced . Velocity through the air. Although at the time Dwyer's conjecture mysterious lightning flashes may be formed by gamma rays released by thunderstorms.
Naturally, it was only a guess. Ultimately, it was not conclusive. The real simulation and the closest neighboring gamma ray formation lightning simulation. It was a joint study this year by the Tokyo Institute of Technology and the Institute of Physics and Chemistry in Japan.
The group sent a gamma ray research team to the Sea of Japan to observe gamma rays formed in lightning at low altitudes. Physical Discovery Gamma-ray bursts were inadvertently discovered in 1967 by Klebesadel and others during the monitoring of nuclear explosions by the U.S. Vela satellite.
The birth of stars and the death of old stars are linked. The supermassive star rapidly ages, explodes, and gives off interstellar dust that rapidly fills the nebula, and the new material from the supermassive explosion is ejected into the nebula, which becomes dense enough to support the birth of a new star.
In galaxies filled with interstellar dust, a great deal of stellar life and death is taking place. Because stars form in regions of interstellar dust, it is hypothesized that the dust clusters that encapsulate dark gamma-ray bursts may be the birthplaces of stars.
Gamma-ray bursts During the Cold War, the United States launched a series of military satellites to monitor the world's nuclei.
What are gamma rays
(Reference reading) Gamma rays, also known as gamma particle streams, are rays released when the atomic nuclei leap metamorphosis of the energy level, is the wavelength of the electromagnetic wave shorter than 0.2 ?. Gamma rays have a strong penetration, can be used to detect injuries in the industry or the automated control of the assembly line. gamma rays have a lethal effect on the cells, and are medically used for the treatment of tumors. 2011 Strathclyde University research in Britain invented the Earth's largest gamma ray, which is used for the treatment of tumors. University of Strathclyde (UK) research invented the brightest gamma rays on earth - 1 trillion times brighter than the sun. This will open a new era of medical research. Gamma rays are electromagnetic waves with wavelengths shorter than 0.2 angstroms [1]. Radioactive atomic nuclei in the occurrence of α-decay, β-decay after the creation of new nuclei are often in the high-energy level, to the low energy level of the leap, the radiation of γ-photons. First discovered by the French scientist P.V. Villard, it is the third type of atomic nucleus ray discovered after α and β rays. Atomic nuclear decay and nuclear reactions can produce γ-rays Y-rays - internal structure model diagram Y-rays - internal structure model diagram . γ-rays have a shorter wavelength than X-rays, so γ-rays have a stronger penetrating ability than X-rays. They can pass through lead plates several centimeters thick. When γ-rays pass through a substance and interact with atoms, they produce the photoelectric effect, the Compton effect, and positive and negative electron pairs. Atomic nucleus released γ photons and nuclear electrons touch, will give all the energy to the electrons, so that the electrons become ionized photoelectrons, this is the photoelectric effect. As the shell layer of the outer shell of electrons appear empty space, will produce the inner layer of electrons jump and emit X-ray identification spectrum. High-energy γ photons (>2 MeV) of the photoelectric effect is weak. γ photon energy is higher, in addition to the photoelectric effect, may also be with the nuclear electrons in the elastic collision, γ photon energy and direction of motion have changed, resulting in the Compton effect. When the energy of the γ photon is greater than twice the static mass of the electron, due to the role of the nucleus and transformed into a pair of positive and negative electrons, the effect of γ photon energy with the increase and enhancement of the γ photon energy. γ photon is not electrically charged, so it can not be measured by the magnetic deflection method of its energy, usually caused by the use of γ photon of the above secondary effects indirectly, such as through the measurement of photoelectrons or pairs of positron energy is deduced. In addition, the energy of γ photons can be measured directly by γ spectroscopy (using the diffraction of γ rays by crystals). Scintillation counters consisting of fluorescent crystals, photomultiplier tubes and electronics are commonly used to detect the intensity of γ-rays. Through the study of γ-ray spectrum can understand the nuclear energy structure. γ rays have a strong penetrating power, industry can be used to detect injuries or automatic control of the assembly line. γ rays on the cell has the power to kill, medical treatment is used to treat tumors. Gamma rays are electromagnetic photons with a frequency higher than 1.5 gigahertz. [1] Gamma rays have no charge or static mass, and therefore have a weaker ionizing ability than alpha and beta particles. Gamma rays are extremely penetrating and carry high energy. Gamma rays can be stopped by nuclei with high atomic number, such as lead or spent uranium.