Scientists have said recently that a new generation of technology is more advanced LIGO equipment, a search for gravitational waves trace amount of days-foot laser at breakneck speed is promoting the construction.
The first generation of LIGO facilities during the run up to 10 years failed to detect any signal of gravitational waves
Gravitational waves are considered from some very high-energy events, such as the merging of two neutron stars
According to the British Broadcasting Corporation (BBC) website reported, scientists said recently that a new generation of technology is more advanced LIGO equipment, a search for gravitational-wave laser trail foot is the amount of days at breakneck speed to promote the construction.
The first generation of LIGO facilities during the 2001-2010 run, but its observations to zero. In the past four years, scientists have designed a more sensitive detector, and achieve fully formed in June of this year, earlier than the scheduled time node.
Research group reported that the new device currently on the sensitivity has to be more than 30 percent higher than the original equipment, and plans to begin summer 2015 observations. LIGO is “Laser Interferometer Gravitational Wave Observatory,” the abbreviation, which is located within the United States two locations, one in Livingston, Louisiana, is another Hanford in Washington State.
Ripples in space
During the British Science Festival, Professor of Physics and Astronomy, University of Birmingham School of Andreas Friis (Andreas Freise) said: “In June, we reached this level, we call ‘locked’, which means that the whole system boot and run a short time, about 10 minutes or so, during which were run according to scientific observation mode. ”
Gravitational waves are ripples in space and time exist in, and it passes through space, like sound waves spread around after the earthquake.
Just for gravitational waves, it’s “source” are some very high-energy events, such as supernovae (stellar death explosions), rapidly rotating neutron stars (extremely dense body of massive stars wreckage), also, or a black hole or Because the track is very close between the neutron star and eventually lead to mutual collision and so on.
With LIGO equipment currently possess the precise extent of this interferometer should be able to detect the occurrence of the Earth at a distance of approximately 27Mpc, namely gravitational wave signal neutron star or black hole binary system to produce approximately 88 million light-years from.
Current research group is still working to improve the system precision optical systems and detection equipment, so as to gradually improve their observation accuracy. Professor Frith said: “Our objective observer can far beyond 200Mpc, than the previous generation of devices that enhance more than 10 times.”
The observation distance increased by 10 times, which means the device can scan LIGO than the first-generation device 1000 times the space.
Also from the School of Physics and Astronomy, University of Birmingham, Albert Wei Qieao (Alberto Vecchio) professor said: “Advanced LIGO facility upgrade in the observation space generation than 1000 times before, in such a large spatial extent, we should expect the signal can be observed gravitational waves. ”
LIGO facilities operating principle is to launch a bunch of powerful laser beam enters a beam splitter, where the laser beam is split into two, each laser beam will be introduced into the tunnel with a length of 4 km of mutually perpendicular. Has a reflector at the top of each tunnel, the incident laser beam is reflected back, eventually recombine at the confluence of two tunnels. Since the length of the two channels of the tunnel is the same, so that when the two laser beams recombine should not show any change. But if there are gravitational waves through the earth, then the situation will change.
Professor Wei Qieao said: “When gravitational waves reach Earth, it will lead to distortions of time and space, in particular, it causes the distance between the two mirrors changes in the four kilometers away, a strong gravitational waves. may result in a change of less than one-thousandth the size of the nucleus on the scale. “This very subtle changes in the mirror will exhibit differences from the laser interferometer, whereby by scientists observed.
Since 2000, a team of scientists at the University of Birmingham, England began to get involved in this project, the leadership of the relevant technologies and hardware developed and participated in a number of professional development tools needed to analyze the data.
The first generation of LIGO facilities compared to the new generation of advanced LIGO Observatory uses an upgraded version of the main reflector suspension system, making it possible to maintain stability, in addition to using a more powerful laser, of course, also improved the overall facility more advanced optical systems in order to adapt to the more powerful lasers.
Although the first generation of LIGO equipment during operation for 10 years and failed to detect any signal, but the study group think after this round of upgrades, advanced LIGO should be able to detect the device during its operational life, at least to a gravitational wave signal.
Professor Wei Qieao think this is probably the most pessimistic estimate in about five years time this device only detects a signal. He said: “reasonably forecast that every year we should be able to detect gravitational waves several events each year and even optimists think we should be able to detect such events hundreds of times.”
Detection results LIGO facilities will constitute an important complement to other experimental facilities, such as the South Pole Telescope Bicep2 and Planck experiments, rather than competition. This is because much of its operating band shorter than the other experiments.
From a scientific point of view, the real significance of detecting gravitational waves would be very far-reaching. Professor Frith said: “There are two main aspects, one of which is related to gravitational theory test, but I think its more interesting aspect is the impact on astronomy us here to enter into uncharted territory, perhaps we detect. to the new signal will tell a lot of people say that you astronomical community was wrong. That’s what I’m trying to do. “(Morrowind)