Super retinal help dark matter satellite monkey
China's first satellite "monkey" dark matter particles has successfully launched.600 mm long BGO (germanium acid bismuth) crystal is like a satellite "super" retina, it can help "monkey" accurate collection of high-energy cosmic ray particles and gamma-ray photons, with a "critical" to spy out the garb of "invisibility cloak" in the universe's mysterious dark matter.
We have learned, "monkey" is internationally known observation can segment the widest range, the optimal energy resolution space probe, is also China's first large space detection device.Cas Shanghai silicate by scientific research personnel for the development of the satellite provides a prototype sample and ZhengYang totaling 640 600 mm BGO crystal, dark matter particles in China satellite payload provides important guarantee for the success of the development and launch.
By the Chinese academy of sciences Shanghai silicate Chen Junfeng Dr., "monkey" is the core of the load by the size of 25 * 25 * 600 cubic millimeter of BGO crystal and photomultiplier tubes can BGO calorimeter.In the satellite payload, the quality of BGO crystal proportion is as high as 59%, as a result, "monkey" can also be regarded as "BGO crystal satellite".
BGO crystal, is a product with possible annihilation of dark matter particles, particles of high-energy cosmic rays and the role of gamma ray photons medium directly.Chen Junfeng said, by the building of BGO can appliance has three advantages: first, read the design adopts double end, signals are integrated backup, can significantly improve the stability and reliability of the system;Second, the dosage of chips and electronics channel number greatly reduced, the corresponding power consumption is also significantly reduced;Third, the power consumption of the payload and quality has fallen dramatically.
600 mm long crystal, it is the only candidate of satellite payload BGO quantity can detect material.Previously, BGO crystals in nuclear medicine, particle physics, nuclear physics, astrophysics, and widely used oil well logging, and other areas of the radiation detection, but the longest internationally known BGO crystal only 400 mm, is still far from the 600 mm.
At present, the Chinese academy of sciences is one of the world by Shanghai silicate was developed and mass production can only 600 mm long BGO crystal suppliers, and holds the world record for the growth of BGO crystal length.
"The dark matter particles exploration satellite launch successfully
With dark matter particles probe of the long march no.2 rocket, December 17, 2015, 8 12 points at jiuquan satellite launch center in China, after successfully into orbit.The mission accomplished, marking an important step China space science exploration research.
It was named the "Monkey King" of dark matter particles probe, is the strategic space of the Chinese academy of sciences pilot project was first developed in science and technology projects, one of the four scientific experiment satellite is observed in all the world to the widest range, the optimal detection of dark matter particles energy resolution satellite.Will load on the dark matter particle detector, high energy electron and high-energy gamma rays in space missions, search for evidence of dark matter, the characteristics and spatial distribution of dark matter.
According to dark matter particles probe chief scientists, Chinese academy of sciences researcher at the purple mountain observatory, regularly to detect dark matter particles satellite orbit for high of about 500 km - the sun synchronous orbit, observed an average of 5 million high-energy particles every day, every day back the amount of data about 16 g, is equivalent to the amount of data of hd movies.Amount of satellite based on mission requirements, the use of BGO can combined with silicon array detector and plastic flash array detector, to complete the measurement of high energy particle energy, direction, charge, and neutron detector to improve the rate of electrons and protons to identify.
Dark matter particles probe is China's first development and production of satellite completely by the Chinese academy of sciences, Chinese academy of sciences national space science center is responsible for the overall satellite project.Satellite is the project demonstration in 2011, in 2012 entered the stage of project development, for satellite orbit is expected to run for three years.Space science satellite project, deputy director, director of the national space science center of Chinese academy of sciences Wu Ji revealed that in addition to the dark matter particles satellite, space science forerunner special series satellite engineering in the near future will also launch three satellites, respectively is quantum science experiment 10, recoverable satellites, practice scientific experiments, hard X-ray modulation telescope satellites.
It is reported, for the launch vehicle, by the China aerospace science and technology group, Shanghai institute of space technology development.This is the 221th long march rocket flight.
"Low profile" of dark matter Scientists in China to see you
Dark matter particles probe in the jiuquan launch on the 17th.It carries with scientists around the world, especially in physics scientists hope.
The dark matter problem is one of the core problems in particle physics and cosmology, now the world many countries in concentrate human, material and financial resources to study this problem.United States national research council, by the authority of 19 physicists and astronomers authored 2002 report, make a list of 11 scientific problem to solve in the new century, among them "what is dark matter" was listed in the first place;At the Chinese academy of sciences in 2050 planning roadmap of innovation, dark matter and dark energy exploration is listed as a revolutionary breakthrough in the basic science problems may come up first.Dark matter and dark energy is thought to be shrouded in physics in the 21st century the two new clouds, their research is likely to bring new scientific breakthrough.
Satellite about detection of dark matter, is not the world's first launch in China.So why China launch of dark matter particles probe?In China it was named "the wu is empty" of dark matter particles what probe is the innovation points?
Dark matter emits no light, no electromagnetic wave, has never been directly to "see".According to the latest astronomical observations, the universe is composed of 27% 68%, 68% of dark energy and dark matter composed of normal matter.For the mysterious dark matter, scientists are eager to know exactly what it is.
Dark matter probe is based on the assumption of the annihilation or decay of dark matter particles, namely the annihilation or decay of dark matter particles can form all kinds of particles and antiparticles to, these particles in space spread is a part of the cosmic rays, and gamma rays.Dark matter probe is to collect high energy cosmic ray particles and gamma-ray photons, through the analysis of the energy spectrum and spatial distribution in search of evidence of the existence of dark matter particles.
Dark matter before the satellite launch in China, Chinese scientists had dark matter detection.Dark matter particles probe chief scientists, Chinese academy of sciences researcher at the purple mountain observatory, has been developed before regularly into a small probe, carrying a long stay in the United States over the atmosphere of the balloon, experimented with two months.Observed in the experiments, the probe in high energy spectrum has some strange phenomenon, scientists speculate that dark matter could be collision produced bright material, located in the very high spectrum.Said, regularly to the observed high energy spectrum, it is necessary to launch a satellite, detector to larger, can see more clearly;And in space, under the interference minimum, satellite flight two to three years, to be able to accumulate a lot of data, you can see the distribution of the energy spectrum is way usually understand and determine the existence of dark matter.
We cannot always do scientific analysis, using data from a other people also can't always rely on satellites carry others do what we want to do science experiments."China's first man-made earth satellite, the east is a launch for 45 years, but so far, China's space science satellite has not yet become series."Space science satellite project, deputy director, director of the national space science center of Chinese academy of sciences said Wu Ji, by contrast, the United States, Europe, Russia, Japan and other countries have done a lot of space exploration targets in science.As a space power, China has not own scientific satellite series.If you want to space powers, you can't do without space science satellite series.We now put forward innovation driven development, cannot always follow behind the others.
On December 17, 2015, probe into dark matter particles is China's first independently by the Chinese academy of sciences research and production of satellites.Compared with previous and international similar satellites, it is innovative.
First of all, the moon's structure is different from the past, China has launched a satellite, it is at the center of the load integration structure design., dark matter, a professor at the university of science and technology of China satellite, deputy chief designer of AnQi said the satellite is to design a platform, the equivalent of a container, then put the payload in among them, the payload can you adapt to the container.Load (detector) and the design of the dark matter satellite is as the center, take the payload centralized place, put the rest of the satellite sail "Mosaic" on the
side of the payload.This design makes the payload of 1410 kg, platform is only 440 kg, the two reached 3.2:1.The load ratio is very high in the world.
Second, it is now the most wide observation can segment in the world scope, space and energy resolution of the world's leading high-energy particle detector.According to regularly, dark matter particle detector belong to large space high-energy observation equipment, it can accurately measure cosmic high-energy particles (electrons, gamma, cosmic rays nuclide, etc.) of the physical characteristics and spatial distribution.Satellite flash array detector is mainly composed of plastic, silicon, can amount of BGO detector array detector and neutron detector of four scientific detection payload.The observation period of covering 0.5 GeV - 10 tev, energy resolution is better than that of 1.5%, more than all the similar detector in the world.It can segment is the international "alpha magnetic spectrometer" 10 times of experiments, the detector energy resolution more than three times higher than the international same kind of detector.
To discover the unknown of the universe -- scientists explanation of dark matter particles probe
When we look up at the starry sky, actually see only the tip of the iceberg of the universe, for the most part of the universe for humans is hidden.Astronomers estimate hat more than 95% in the universe is a human has yet to understand dark matter and t
dark energy, less than 5% of ordinary matter is known.
Dark matter, the invisibility cloak "ghost" the universe, scientists know that they exist, only can't detect them.China's scientific satellite series starting probe - dark matter particles "monkey" the successful launch at the jiuquan satellite launch base, its mission is to use "critical" to search for evidence of the existence of dark matter particles.
"This is the first time Chinese scientists placed their high resolution in space high-energy space telescope."Dark matter, vice head of the purple mountain observatory satellite's chief scientist said regularly, "it will profoundly change the world outlook of human, achieve a major breakthrough in space science."
Why do you want to look for dark matter?
For frequent, dark matter is like a friend who have never met, is cordial and familiar.
"Matter in the universe, we can see, because with electric and can" glow ", we can touch a table, a wall, feel their existence, because of the interaction of electromagnetic field. The dark matter is without charge, nor the interaction of
electromagnetic field, and can penetrate the blockage, like a ghost without trace from flies."Regularly said. "so although there is dark matter around us, for example, the average 1 cubic centimeter might have thousands of dark matter particles in the air, but we can't see or feel it."
Scientists believe that dark matter is the product of the big bang, plays a decisive role in the evolution of the universe, also decides the fate of the universe in the future.At the same time, the dark matter and dark energy's research also has important significance in fundamental physics, because of the scientific community accepted standard model of particle physics can explain only 4.9% of the universe ordinary matter, but can't explain the dark matter and dark energy.
Thus, dark matter and dark energy is thought to be enveloped in physics in the 21st century's two "black clouds".Scientists in the United States are listed in a report in the 21st century to solve the 11 scientific question, "what is dark matter" was listed in the first place.
The scientific community recognized, the mystery of dark matter will be the heliocentric theory, the law of universal gravitation, relative deals with quantum mechanics after another major leap, will bring another revolution in physics.
Wu Ji said, director of the national space science center of Chinese academy of sciences, particle of dark matter detection is currently the most competitive international science frontier field of study, scientists all over the world in spare no effort to search for dark matter, dark energy and the great scientific treasure hidden.
"But so far, people find also are some suspected evidence."Wu Ji said, "human haven't found it yet, and I don't know its quality, properties, and can't use the standard model to explain physics."
Dark matter is human life is so far away, why spend so much time, effort and cost to look for?Scientists answer, which on the one hand, stems from the human for unknown curiosity and thirst for knowledge, and on the other hand, the value and significance of scientific research although sometimes can't appear in the short term, but will often bring some "by-products", to science and technology and life bring change.
How to search for "ghost" the universe?
At present, the world of dark matter detection way is mainly divided into three classes.The first is through two beam of high-energy particle collisions on the accelerator to "create" dark matter particles, such as CERN's large hadron collider (LHC);Direct detection of the second class was conducted in underground, where they have a lot of such experimental projects, including sichuan of China kam screen underground laboratory is currently the world's deepest dark matter research laboratory;The third kind is indirect detection in space.
China's dark matter particles orbiter belongs to the third method.The method how to looking for dark matter?Explained that regularly into the world of matter with antimatter, when a substance meet a antimatter, will both be destroyed, the resulting huge amount of energy.But the dark matter is very unique, it is antimatter itself, if dark matter particles and their antimatter particles collide, more energy is generated.
"If can detect dark matter particles collision produced by high energy particles, such as gamma rays, such as positrons and antiprotons, neutrinos, and be able to accurately measure the particle energy spectrum, can indirectly prove the existence of dark matter."The handiest said.
Using the same method and Nobel laureate Samuel ting developed and placed on the international space station of the alpha magnetic spectrometer 2 (AMS02) and the amount of Japan was launched in 2015, to implement electronic telescope, etc.The AMS02 has observed some exceptions, but because of the limitation of observation can segment, fewer data, and also can't jump to conclusions.
"China is so far of dark matter satellite can segment the widest range, the optimal energy resolution space probe, more than all the similar detector in the world."Scientific satellite application system architect Ken ng said, the period of 10 times the alpha magnetic spectrometer, covers the electronic energy spectrum and the photon energy spectrum anomaly takes place;Its energy resolution more than three times higher than international similar detector.
"Is the last of human space lab, the highest energy cosmic rays is higher than the biggest accelerator has more than 100 million times."Regularly said, "put forward by the dark matter of China satellite observation object and observation can area are so far for the first time in the world."
"Human each first observation, there are many scientific discoveries can't foresee, we expect this observation can also be found that many humans' first 'unknown."The handiest said.
"The wu is empty" how to use "avatar"?
Dark matter satellite "monkey" the width is only 1.5 meters high, 1.5 meters, 1.5 meters, not much bigger than a desk.
"Its volume is small, the function is very powerful."Introduced regularly, satellite payload prototype sample three times in CERN beam experiment to test the physical performance index, shows that it has high energy resolution, measuring energy range and background suppression 3 big advantage.
Chief designer hua-wang li satellite system, satellite consists of four scientific detection payload, flash array detector are plastic, silicon array detector, BGO quantity can implement and neutron detectors, constitute a high-energy particle detector telescope.Four detector stack from top to bottom, is like a four layer "big cake", they do their job, and the joint mission, can accurately measure the type, direction, the energy of incident particles and charge.
After entering the space, "the wu is empty" will be 500 km sun-synchronous orbit.It will take two observation models: adopt the survey mode during the first two
years, because of the dark matter may exist Yu Quantian in any area, so the first stage to scan all day;Directional observation satellite into mode after two years, according to the area to detect all day out of the dark matter is most likely the result of analysis of region, and aims at these areas to carry out directional observation.
Satellite every day will be back about 16 g data volume, the ground more than 100 people in the team of scientists will conduct analysis of data.The first scientific results may be published after 6 months to 1 years.
Many teams in the world in search of dark matter, but so far have never detected dark matter clear signal.Regularly admitted that the basic physical properties of dark matter has not been made clear, no one can guarantee one hundred percent find dark matter."But as long as the satellite working properly, it will open a door for our observations of the universe new window, will find a lot of novel phenomenon."The handiest said, looking for dark matter needs efforts from scientists around the world.