Radiofrequency cavity

Figure 7.4 Proposals of hardware for QC. (a) Ions trapped in a radiofrequency cavity and cooled by lasers (b) molecule used to implement Shor s algorithm with NMR using...

The radiofrequency cavity system (RF in Figure 2.4), which acts on the circulating electrons and restores the energy they lose through the emission of electromagnetic radiation. 

Figure 2.4 Schematics of a synchrotron radiation facility. The closed circuit on the left represents the storage ring. IS, injection system RF, radiofrequency cavity L, beamline BM, bending magnets FM, focusing magnets ID, insertion device.

U = Undulator M = Optical Cavity mirror B = Bending magnets and focusing elements C = Radiofrequency cavity. 

The risks involved are those related to human exposure to prompt radiation due to the circulation or injection of beams, radiation generated by radiofrequency cavities used for accelerating beams, induced or remnant radiation in equipment or in the air. 

Goodwin, A.R.H. and Mehl, J.B., Measurement of the dipole moments of seven partially fluorinated hydrocarbons with a radiofrequency reentrant cavity resonator, Int. J. Thermophysics, 18, 795-806, 1997. 

Figure 1 Apparatus of Oxford experiment [6]. LI, L2 tunable dye lasers. UV ultra violet radiation (243 nm). RF radiofrequency dissociation of flowing molecular hydrogen. PI signal photomultiplier (Lyman-a detector). P2 photomultiplier for cavity locking and signal normalisation. SI cavity length servo-control. C conrouter. AOM acousto-optic modulator. T heated quartz cell containing tellurium. S2 laser frequency servo-control. D fast photodiode...

The usual arrangement employs an air-cooled silica discharge tube of about 10 mm internal diameter. Various types of microwave cavities suitable for coupling power ( 25 to 200 W) to the discharge tube are used, whilst radiofrequency power is coupled either by means of a pair of metal sleeves around the outside of the discharge tube, or inductively. It appears that the yields of atoms under the same conditions from microwave (2450 MHz) and r.f. (20 MHz) discharges are similar. 

A plasma may be defined as a gas containing a relatively large number of ions and free electrons. To produce a plasma, an energy source is required and for analytical atomic spectroscopy three different excitation methods have been used. They are (1) a dc arc, (2) radiofrequency energy coupled through a microwave cavity, and (3) radiofrequency energy inductively coupled to the plasma. 

The experimental realization is based on the comparison of the optical frequency comb with the Cs-atomic clock, which represents up to date the frequency standard. A dye laser at X = 486 nm is stabilized to a frequency vi which differs from the frequency Vc of one of the teeth of the optical frequency comb by the radiofrequency /i. The output of the dye laser is frequency doubled in a BBO-crystal and is then sent collinearly to the H-atom beam into an enhancement cavity, where it excites the two-photon transition 15 -> 25 of the H-atom [1326]. The radio-frequency... 

CW ENDOR is considered in this section pulse ENDOR is dealt with below. The instrumentation is usually based around a computer-controlled CW ESR spectrometer and is commercially available. A radiofrequency coil, capable of handling up to 1 kW poweg is used to introduce the NMR frequencies. The coil is contained in a special resonant cavity. Various modulation strategies are employed to improve the signal-to-noise ratio. In order to carry out the ENDOR experiment, the spectrometer is set for a given line in the ESR spectrum. The microwave power is increased to just beyond the saturation level, and then the selected NMR frequency is swept. Two NMR transitions are observed at the frequencies ... 

Electron concentrations have been measured by radiofrequency resonant circuits " in which the flame is placed inside a coil or condenser which is part of a resonant circuit. Electron concentrations have also been obtained by cyclotron resonance/ microwave scattering/ microwave absorp-tion/ microwave interferometry/ and microwave cavity reso-nance. " All of these methods for measuring electron concentration have the advantage of not perturbing the flame, but suffer from the disadvantage of poor spatial resolution. Also, measurements can be made only over a relatively limited range of concentrations—typically, one or two orders of magnitude. 

Radiofrequency Spectroscopy inside a Laser cavity MBMW frequencies [77D1] were included in the fit. 

Electrodeless discharge lamps have a small, sealed cavity containing a minute amount of the element to be measured, or its salt. The cavity is excited by a radiofrequency signal passed through a coil, and tuned to resonate at a chosen frequency. This excites the atoms to produce the desired emission spectrum. 

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