Ion trapping techniques
... By way of a caution it must be noted that while the (au – qu) stability plot indicates regions of ‘mathematical’ stability, there are others factors which could cause ion loss. These include situations where ions, formed close to one of the electrodes (rather than at the centre), collide with the el ...
... By way of a caution it must be noted that while the (au – qu) stability plot indicates regions of ‘mathematical’ stability, there are others factors which could cause ion loss. These include situations where ions, formed close to one of the electrodes (rather than at the centre), collide with the el ...
TEP 5.4.00- 10 Counter tube characteristics
... counting wire. However, they only reach the counting wire if they do not recombine with the gas particles on their way. If the counter tube voltage is too low some of the pulses are lost on their way, and the resulting signal will not be conclusive (recombination range). When the voltage is increase ...
... counting wire. However, they only reach the counting wire if they do not recombine with the gas particles on their way. If the counter tube voltage is too low some of the pulses are lost on their way, and the resulting signal will not be conclusive (recombination range). When the voltage is increase ...
5 - ENEA AFS Cell
... be employed to check the condition and operation of anode and cathode, see Fig. 7.2. During normal conditions the VV will be at room temperature (20 °C) with a vacuum of ~10-8 mbar. However provision will be made to bake the machine up to 80-90 °C. Such a baking temperatures are effective in removin ...
... be employed to check the condition and operation of anode and cathode, see Fig. 7.2. During normal conditions the VV will be at room temperature (20 °C) with a vacuum of ~10-8 mbar. However provision will be made to bake the machine up to 80-90 °C. Such a baking temperatures are effective in removin ...
Pulsed Nuclear Magnetic Resonance
... adjust the DC magnetic field to maximize the PNMR decay. Be careful, there will be several apparent maxima at different fields; be sure to find the absolute maximum. Ask the TAs to show you a method of identifying the maximum using the presence of beating in the signal. Note: for fine adjustment of ...
... adjust the DC magnetic field to maximize the PNMR decay. Be careful, there will be several apparent maxima at different fields; be sure to find the absolute maximum. Ask the TAs to show you a method of identifying the maximum using the presence of beating in the signal. Note: for fine adjustment of ...
Cavity magnetron
The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of open metal cavities (cavity resonators). Bunches of electrons passing by the openings to the cavities excite radio wave oscillations in the cavity, much as a guitar's strings excite sound in its sound box. The frequency of the microwaves produced, the resonant frequency, is determined by the cavities' physical dimensions. Unlike other microwave tubes, such as the klystron and traveling-wave tube (TWT), the magnetron cannot function as an amplifier, increasing the power of an applied microwave signal, it serves solely as an oscillator, generating a microwave signal from direct current power supplied to the tube.The first form of magnetron tube, the split-anode magnetron, was invented by Albert Hull in 1920, but it wasn't capable of high frequencies and was little used. Similar devices were experimented with by many teams through the 1920s and 30s. On November 27, 1935, Hans Erich Hollmann applied for a patent for the first multiple cavities magnetron, which he received on July 12, 1938, but the more stable klystron was preferred for most German radars during World War II. The cavity magnetron tube was later improved by John Randall and Harry Boot in 1940 at the University of Birmingham, England. The high power of pulses from their device made centimeter-band radar practical for the Allies of World War II, with shorter wavelength radars allowing detection of smaller objects from smaller antennas. The compact cavity magnetron tube drastically reduced the size of radar sets so that they could be installed in anti-submarine aircraft and escort ships.In the post-war era the magnetron became less widely used in the radar role. This was because the magnetron's output changes from pulse to pulse, both in frequency and phase. This makes the signal unsuitable for pulse-to-pulse comparisons, which is widely used for detecting and removing ""clutter"" from the radar display. The magnetron remains in use in some radars, but has become much more common as a low-cost microwave source for microwave ovens. In this form, approximately one billion magnetrons are in use today.