But when poachers carrying rifles or machetes traipse by a detector, it will send a radio signal to a treetop antenna.
The hoard of 201 coins and pieces of jewellery was found in September near to Silverdale by metal detector enthusiast Darren Webster, 39.
If any of these targets matches the video frame, the corresponding reference beam is emitted by the memory, and picked up by a detector.
The figure was found last February by metal detector enthusiasts last in Burrington, North Somerset, near the Roman lead mines on the Mendip Hills.
When a tsunami passes by, the detector records the increased pressure caused by its passage.
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More than 3, 500 Anglo-Saxon artefacts were discovered by a metal detector enthusiast in a farmer's field in Staffordshire in July 2009.
The items, which date from the ninth century, were found in 2002 on the banks of the River Bann near Kilrea by a metal detector enthusiast.
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Saudi officials believe that the prince's assailant exploded the 100-gram device using a detonator with a chemical fuse, which would also not be detected by a metal detector.
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Tata said the extra security measures would not have stopped the attackers from entering the building because they went through a kitchen door that was not monitored by a metal detector.
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That's the goal at a shop at Harvard, where Daniel Branton, a biophysicist, and his colleagues hope to design a better detector by passing DNA--a letter at a time--through a microscopic "nanopore" in a silicon membrane.
That is the goal at a shop a few miles down the road from U.S. Genomics, at Harvard, where biophysicist Daniel Branton and colleagues hope to design a better detector by passing DNA, one letter at a time, through a microscopic "nanopore" in a silicon membrane.
The coins were discovered by two amateur metal detector enthusiasts, Reg Mead and Richard Miles who began their hunt after a woman told them her father had found coins in a field some years before.
That is not very exciting by itself, but this detector counts single photons (the particles of which light is composed) and can do so at room temperature.
The NOvA detector will be operated by the University of Minnesota under a cooperative agreement with the U.S. Department of Energy's Office of Science.
The light-sensitive area on each CCD detector measures 45.0mm by 59.0mm, encompassing 1, 966 pixels by 4, 500 pixels.
Neutrinos created by collisions in the atmosphere above the detector would probably not have had time to change identity before they arrived.
When particles crash into the semiconducting material at the heart of their detector, they heat it by tiny amounts, which it records.
"The archaic system of an X-ray machine and metal detector cannot pick up other potential threats posed by passengers, " Baum says.
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But CNN has learned that the inmate has failed a number of lie detector tests regarding the details -- described by some sources close to the investigation as vague -- of the plot.
When your name was called, you were passed through a metal detector and ferried upstairs to an undecorated 6-by-6 cubicle.
By 1930, such vacuum-tube diodes had all but replaced the quirkier crystal detector.
Using the first completed section of the NOvA neutrino detector, scientists have begun collecting data from cosmic rays-particles produced by a constant rain of atomic nuclei falling on the Earth's atmosphere from space .
After passing through the shelter's metal detector and enjoying a long wait in a bucket seat, I was greeted by a tall man with a kind face.
That Tron-ish, equalizer-like graphic is actually a 3D representation of particle activity left behind by cosmic rays interacting within NOvA, the Department of Energy's under construction neutrino detector.
The detector allows the machine's operators to work out which particles have been created by the electron-positron collisions, and to follow their patterns of decay.
In 2002, a test by Sandia labs in the US found that a similar dowsing rod device, called the Mole detector, did not work and performed "no better than a random selection process".
London (CNN) -- The maker of a fake bomb detector that investigators say put lives at risk was sentenced Thursday to 10 years in prison by a London court.
Dr Krausz did it by recording the arrival times of different electrons using a piece of equipment called a multi-channel plate detector.
Light striking this detector liberates electrons from some of the silicon atoms, producing an electrical signal that is converted by the chip's electronics into a picture.
The camera works, the team explained, by bouncing lasers off distant objects, and measuring the time it takes for the light to travel back to the detector.
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