this mass threshold was derived from the detector calibration and an assumed impact velocity of Af.

If a detector was placed at a distance of 1 m, the ion flight times would be X and Y ns.

The crystal detector was developed into a practical device for wireless telegraphy by Greenleaf Whittier Pickard, who invented a silicon crystal detector in 1903 and received a patent for it on November 20, 1906.

This troublesome device was superseded by thermionic diodes by the 1920s, but after high purity semiconductor materials became available, the crystal detector returned to dominant use with the advent of inexpensive fixed-germanium diodes in the 1950s.

In the SEM image of an ant shown at right, the image was constructed from signals produced by a secondary electron detector, the normal or conventional imaging mode in most SEMs.

After the development of his electron capture detector, in the late 1960s, Lovelock was the first to detect the widespread presence of CFCs in the atmosphere.

His invention, known as the Polish mine detector, was used by the Allies alongside mechanical methods, to clear the German mine fields during the Second Battle of El Alamein when 500 units were shipped to Field Marshal Montgomery's Eighth Army.

According to the 9 / 11 Commission Report, Moqed set off the metal detector at the airport and was screened with a hand-wand.

This was made possible by the development of a secondary-electron detector

The detector was designed to detect solar neutrinos through their interactions with a large tank of heavy water.

The detector cavity outside the vessel was filled with normal water to provide both buoyancy for the vessel and radioactive shielding.

The SNO detector would have been capable of detecting a supernova within our galaxy if one had occurred while the detector was online.

The detector, named KamiokaNDE for Kamioka Nucleon Decay Experiment, was a tank in height and in width, containing 3, 048 metric tons ( 3, 000 tons ) of pure water and about 1, 000 photomultiplier tubes ( PMTs ) attached to its inner surface.

The detector was upgraded, starting in 1985, to allow it to observe solar neutrinos.

As a result, the detector ( KamiokaNDE-II ) had become sensitive enough to detect neutrinos from SN 1987A, a supernova which was observed in the Large Magellanic Cloud in February 1987, and to observe solar neutrinos in 1988.

The detector was partially restored by redistributing the photomultiplier tubes which did not implode, and by adding protective acrylic shells that are hoped will prevent another chain reaction from recurring ( Super-Kamiokande-II ).

The work was completed in June 2006, whereupon the detector was renamed Super-Kamiokande-III.

However, on March 26, 1983, the first test, known as the Cabra event, was performed in an underground shaft and resulted in marginally positive readings that could be dismissed as being caused by a faulty detector.

Since a nuclear explosion was used as the power source, the detector was destroyed during the experiment and the results therefore could not be confirmed.

If the light is turned on and off at the frequency corresponding to the Earth's field, there is a change in the signal seen at the photo detector.

One proton detector was turned off during the second day of operation because of noise.

The spark at the buzzer's electrical contacts served as a weak radio transmitter, so when the detector began working the buzz could be heard in the earphones, and the buzzer was then turned off.

The MIT and ARC Plasma Analyzers as well as the cosmic ray detector from University of Chicago were turned on and working.

Some telemarketing firms have turned off the SIT tone detector altogether in response to the TeleZapper trick, rendering it wholly ineffective.

Critics alleged that the suspicions that Shcherbakov was a double agent which emerged when Shcherbakov turned down a promotion requiring a lie detector test should have been followed up more aggressively.

* Imperfections in the detector: failing to detect some photons or detecting photons even when the light source is turned off ( noise ).

The diurnal variation in the observed flux may be partly due to the dependence of the detector sensitivity on the incident velocity.

By " time-gating " the detector for the arrival of a particular species of interest its crystallographic distribution on the surface, and as a function of depth, can be determined.

The appearance of interference built up from individual photons could seemingly be explained by assuming that a single photon has its own associated wavefront that passes through both slits, and that the single photon will show up on the detector screen according to the net probability values resulting from the co-incidence of the two probability waves coming by way of the two slits.

In its mathematical form it is analogous to the description of a physical wave, but its " crests " and " troughs " indicate levels of probability for the occurrence of certain phenomena ( e. g., a spark of light at a certain point on a detector screen ) that can be observed in the macro world of ordinary human experience.

If a ray tracing is then made as if a light wave ( as understood in classical physics ) is wide enough to take both paths, then that ray tracing will accurately predict the appearance of maxima and minima on the detector screen when many particles pass through the apparatus and gradually " paint " the expected interference pattern.

A detector is placed so as to collect these repelled ions ; the image formed from all the collected ions can be of sufficient resolution to image individual atoms on the tip surface.

The sixteen instruments, weighing 118 kg altogether, included magnetometer sensors mounted on an 11 m boom to minimize interference from the spacecraft ; a plasma instrument for detecting low energy charged particles and a plasma wave detector to study waves generated by the particles ; a high energy particle detector ; and a detector of cosmic and Jovian dust.

It also carried the Heavy Ion Counter, an engineering experiment added to assess the potentially hazardous charged particle environments the spacecraft flew through, and an added Extreme Ultraviolet detector associated with the UV spectrometer on the scan platform.

* Detector Spots Buried Mines 1943, Popular Science article on the " Polish " mine detector.

* A trapped radiation detector, mounted on the body with counter-axes pointing 70 ° and 135 ° from the solar direction, to measure the intensity and direction of low-energy particles.

* A cosmic dust detector, mounted on the body with microphone plate approximately perpendicular to the plane of orbit, to measure the momentum, distribution, density, and direction of cosmic dust.

The cosmic dust detector registered 17 hits in a 15 minute span on September 15, part of an apparent micrometeoroid shower which temporarily changed the spacecraft attitude and probably slightly damaged the thermal shield.

The point-contact crystal detector became vital for microwave radio systems, since available vacuum tube devices could not serve as detectors above about 4000 MHz ; advanced radar systems relied on the fast response of crystal detectors.

The brightness of the signal depends on the number of secondary electrons reaching the detector.

The Cherenkov light is projected as a ring on the wall of the detector and recorded by the PMTs.

SK-IV continues to run, collecting data on various natural sources of neutrinos, as well as acting as the far detector for the Tokai-to-Kamioka ( T2K ) long baseline neutrino oscillation experiment.

It gives better S / N ratio on the detector output.

Alexander Stepanovich Popov demonstrated to the public his wireless radio receiver, which was also used as a lightning detector, on May 7, 1895.