In this nightmare scenario, 100,000 members of the rescue teams looking for survivors or bodies. There are areas that have not even been able to reach hundreds of miles of coastline destroyed, thousands of people they do not have news and apocalyptic landscapes, such as that offered by the city of Sendai, in which looks for signs of life. "It's hard to imagine something. I came to Miyagi to help in the latest quake, but then there was no water. This is something completely different. Unimaginable, "says a member of the rescue teams.
More than 200 bodies have been found in the coastal town of Higashimatsushima, between 300 and 400 in the port of Rikuzentakata, 300 Sendai beach and do not have any news of 10,000 people, more than half of the population, the coastal town of Minamisanriku. Missing
also four trains integers. Boats stranded in the middle of nowhere are witnessing a tsunami that swept away more than 20,000 buildings and penetrated five kilometers into the mainland. Hundreds of thousands of people have been evacuated. Many expect hungry emergency centers help arrives.
More than 10,000 dead in Miyagi, according to Japanese police smith: IceCube Observatory There
big big engineering work during construction to go unnoticed by most of the world. The IceCube Neutrino Observatory
is a good example of this: buried under the South Pole has been kept away from reporters during the 10 years that has lasted construction. This "telescope " which was completed late last year, is responsible for observing the universe, but instead of using radio waves or visible light, it will detect (see) neutrinos. The problem that exhibit this type of equipment (detectors) is that neutrinos are extremely difficult to detect particles as hardly interact with matter. Trillions of them pass through our planet every second, every square meter of surface, but by its very small mass (Slightly less than one billionth the mass of a hydrogen atom) rarely collide with any atom, so they are virtually undetectable. Are particles so small they slip between the particles of the nucleus and electrons revolving around it, without hitting them.
Neutrinos are the smallest known particles. The high energy have caused by various astronomical phenomena such as black holes or supernova remnants (explosions that are created with the death of some stars), among other causes. The low energy is produced from different processes, such as nuclear reactions or astronomical bodies like the sun, resulting in about 1,000 trillion trillion neutrinos of low energy per second. would take a lead wall a light year thick (about 10 trillion kilometers) to stop the course of a neutrino. This elusive particle is what a scientist has called the smallest amount of reality that humans can imagine. They originated, along with the rest of the universe, about 13,000 million years, but are also produced by nuclear plants, particle accelerators, atmospheric and astronomical phenomena. A neutrino is so, so tiny, so much so that at first physicists thought they had no mass, then found itself. But interact with matter so little that cross without causing any change in her. And that is why they are so difficult to detect. 
The observation of these tiny pieces of the universe is useful to know more about issues of concern to scientists as cosmic rays, supersymmetry or weakly interacting particles, as well as various aspects of particle physics and dark matter. In other words, neutrinos may help to better understand how the universe is made and what are their origins.
These particles are so tiny they interact very little with matter, namely that cross without causing any effect on him, and without which neither she nor interference, affect them. Therefore, despite the distance between our planet comentadosy astronomical phenomena, neutrinos can travel millions of miles between for example the explosion of a supernova and the Earth at a speed approaching that of the light without being affected by anything in its path. Cross the globe continuously at a rate of a few trillion of them per square meter per second. Pass through everything, including the magazine you hold in your hands, and yourself, and follow their path without being detected.
not all get to pass through matter and a few, very few among the many trillions, clash with some atom from time to time. The collision is what scientists, thanks to technology, are able to detect, so that statistics can draw some conclusions about that fact. The effects of collisions with atoms are not easy to observe and therefore need to have technology very special to do so: a good option that scientists have found is to use an ice cube size of 1 km3 sewn by a network of 4,800 sensors, in turn, are connected to a laboratory equipped with powerful computers. While it does not seem from the description, it is a telescope. 
In the clash of atoms produce neutrinos and other particles called muons. They generate a radiation, called Cherenkov, which emits blue light. Because the sensors
mesh is placed in a transparent medium, the ice, they can detect that flash when the muon passes them. Not all muon neutrinos are generated by source cosmic, which are of interest to scientists, so they need to deduce the direction and angle of the muons to determine their origin and discard the impacts that they are responsible for their studies. Since the sensors are a three dimensional mesh of points and their clocks are synchronized very accurately with other central, according to data collected from position and time, it is possible to know where the muon has passed along a timeline and, therefore, to know its history.
In addition the system is also called IceTop installed, a network of 320 sensors on the surface around the perimeter of area that displays the IceCube. Its function is to detect air showers, atmospheric muons analyze and calibrate IceCube. Digital Optical Module (DOM or digital optical module) is the name given to each of the sensors that detect blue light emitted by the radiation of muons when the telescope observe the universe. These sensors are the size of basketballs. Its housing is a glass sphere of 35.6 cm in diameter that protects the external pressures exerted by the ice, as well as any potential foreign aggression.
The photomultiplier tube is the most important part of the DOM, since it is concerned to see the light emitted by the radiation from muons. Is 25 cm in diameter and is manufactured by Hamamatsu, a specialist in this type of light detectors. Without access to the modules once led to its final position, these are engineered to last about 15 years ago, being able to gauge for themselves the photomultiplier tube and the timer which incorporate, manage data collected and packaged for shipment, as well as receive and process orders from the surface. 
To send and receive data to the laboratory installed at ground level (which is the real brains of the whole project) uses a cable that also serves to provide the electricity needed for the operation of the DOM, namely 3.5 W for each of them. This link also sends copper pair calibration signals for the timers, a fundamental system-wide view of the precision with which is essential to work.
drum assembly to pick up the hose used to drill water heaters.
develop these special detectors is only part of the work to get them working. The other task has been installed under the floor of Polosur, some so deep as 2.4 km. It should, therefore, drill a hole 50 cm in diameter on ice. It may seem small, but when the water is frozen and have to reach the 2,400 m depth, the issue is complicated. 
First of all is essential to reach the ice. In Antarctica you have to cross a layer of 50 feet of snow to drill water heaters, because otherwise the liquid would spread and could not do the job. To practice this first hole using a probe designed for this purpose. Once it has reached the ice starts to apply pressure hot water. With it melts the ice water, which in turn is recirculated to the surface, heated and reused for further drilling. To run a single hole of 2.4 km depth necessary to melt more than 757,000 liters of ice and liquid extract, which gives an idea of \u200b\u200bthe size and difficulty of the operation. To make that amount of liquid water ice is required to spend nearly 26,500 liters of fuel (fuel has been used aircraft engines) in order to operate multiple systems. One of them is devoted to the production of electricity. It consists of two 400 kW generators and two of 60 Kw. The big serve to provide all the electricity needed when you are drilling and small only when it is not boring and does not require much electrical power. Another
reservation system for preheating water. It can raise the temperature of the liquid from a temperature close to freezing (which is just liquefy and remove the hole that was being practiced at that time) to just over 21 ° C at a rate of 757 liters per minute . There is another water heating system, which is the main, which raises the temperature to about 88 ° C. Finally, a system consisting of four high pressure pumps electrically driven, which are responsible for promoting the water with the force required to perform the work through a hose 6.35 cm in diameter.
Celebrating the end of the telescope.
whole system depended on the surface of two drilling rigs. While one was busy digging a hole and installing the sensors, the other moved to a new location and prepared for the job. In this way, they can maintain a production pace that allows them to practice and implement a hole 2,400 meters depth in three díasy medium. In that period, between 40 and 48 hours are only drilling. Despite this ability to drill, just like the weather only allowed to work in the Antarctic summer, from November to mid February, had to use mandatory several years to complete the entire project. 
When finished each well, the drilling head mounted devices ", including a pressure sensor, which sends data to the technicians on the depth reached and the size of the hole, in order to determine whether it qualifies for the installation of digital optical modules. In total they had to play 80 of these holes. After drilling and testing of the opening in the ice is necessary to place the sensors that detect radiation from muons, as a result of collisions of neutrinos.
For every hole that is practiced on the ice introducing a communication cable and power to which they are attached a total of 60 DOM, so they are like beads on a huge rosary in the frozen water, using an umbilical cord attached to a host system that reaches the project lab. The installation of the sensors must be done carefully to avoid damaging them. The procedure involves placing in position and only seven people fixing to phase the main communication cable and power requires the efforts of three of them, although the outcome depends largely on previous work of a fourth, a coordinator. This manager has to calculate the time it takes to perform this operation and decide according to how wide it is necessary to drill hole without oversize and, therefore, no need to spend more fuel. Once over to pierce the ice starts the countdown, so it is imperative not to exceed the estimated time, and that as it advances the well begins to freeze again and gradually narrows. If a delay is possible then the possibility that the sensor cable to get stuck without reaching your destination and let the DOM frozen in a position to perform their work useless.
in communication with drilling rigs and installation are air-conditioned barracks that provide access to the computer network and electrical power. In these units is necessary to prepare the sensors to connect with a good rhythm and to develop some final tests. The batch of 60 DOM that is located in each hole comes from the central laboratory, where it has been checked for proper functioning of electronic and mechanical. The sensors are joining the main cable into groups of four, after which he proceeds to do some final checking of communication before placing the next group.
The connection of each DOM is done through a process to facilitate safe handling, passing the main cable tension (When fixing the sensor) to the winch of the drilling rig. Once the connections have been made precise, is passed back to the main cable tension and allowed to fall through the hole. The cable is straight into the hole, even before the first sensor pair, thanks to a drag of 2.27 kg which is set at its lower end.
As soon as we have introduced 60 DOM in the well, this is closed with a lid and makes a data connection and power cable to a network installed on the surface, which in turn is connected to the main lab project . The network is available even before they drill the ice, so that within a few hours to finish to set each line of sensors are already beginning to receive data.
The network consists of hubs (hubs) to which are attached several DOM. The hubs of the same line of sensors bound to a processor, which is responsible for collecting the data for each DOM string of each hole. All online processors in turn send their data to mainframes event builders called
(rebuilders of events), whose function is basically to analyze the information in search of that is relevant to the project.
The event builders are housed in the ICL (IceCube Laboratory), a building which also houses the offices of the project, the Boards of electronic maintenance and logistics units. From this building the information collected is sent, via a NASA satellite, a center Data from the University of Wisconsin (USA), while that ruled stored on disks that physically transport the return trip to the U.S. team at the end of each drilling season.
data arriving in Wisconsin from the South Pole 326 is copied to hard drives totaling 120TB (about 120,000 GB of capacity.) A dozen powerful servers are responsible to share this enormous amount of information to the workstations. Finally the results are saved to tape high capacity of 500 GB each. They stored each night every night what could be termed as the voice of the stars. Conceptually, the IceCube project strategy is simple, but behind her is a whole scientific development leading up to and execution, a remarkable technical display. Also important has been the experience of other similar initiatives installed in the same place as the new telescope: the
AMANDA (Antarctic Muon
Neutrino Detector Array or in Castilian, matrix Antarctic Muon detection and neutrinos). The center of all the IceCube project is based on a tool consisting of a mesh or matrix in which detectors are fine, as was already using AMANDA, only this used 677 sensors divided into 19 lines that reach a depth of 1,900 meters . All of them are now part and integrated into the new IceCube. The construction project has involved 400 people and have spent $ 271 million. The IceCube Neutrino Observatory
is in Antarctica. To be a remote possibility that a neutrino "clash" with a detector, the observatory needs to have a huge size. The assembly of the IceCube Neutrino Detector Observatory occupies about one cubic kilometer. So that its operation is not affected by other particles or radiation, has installed 1,400 meters below the surface of the ice covering the South Pole. In its design and construction have involved scientists United States, Belgium, Germany and Sweden, and the device will be operated by the University of Wisconsin-Madison and the National Science Foundation. drill head heated with hot water.
The graph shows the cable lines that hold the detectors 
in wells shows the Eiffel Tower, to compare its size. It has taken about 10 years of work to get it ready, on 18 December, introduced the past 86 photodetectors and their cables to a depth of two miles and a half, assuming completion of the work that has cost 270 million dollars. Each these sensors has been put in place within the block of ice through deep holes. These holes were made using a special drill did his job by a special head turned to hot water, extracted total cubic ice 757 meters, for each of the wells of 2.4 kilometers. Had to perform hundreds of wells with a depth between 1,400 and 2,400 meters to install each of the sensors and connecting cables.
Here is one of the wells with the cable that connects the sensors hanging from it.
This is the first sensor is lowered to the ice well.
Neutrinos can not be observed directly. Instead, it follows neutrino kinematics information through the detection of rare collisions that occur between a neutrino and an atom, a molecule of water within the ice. Estimates predict current to be detected close to a thousand of these collisions per day.
Due to the high density of ice, almost all detected products of the initial collision will be muons. Therefore this experiment is more sensitive to flow
muon neutrinos through its volume. However, there are also plenty of background muon neutrinos created not only by cosmic rays impacting the atmosphere above the detector, most of these can be immediately rejected by the fact that from the top of the detector. Most of the neutrinos 'upstream' the remaining come from cosmic rays striking the opposite side of the earth, but an unknown fraction may be of astronomical origin.
ZexonaZ. Things happen.
0 comments:
Post a Comment