摘要:

Impurity concentration in intense neutral beams extracted from both a 75 keV/6 A/10 s duoPIGatron ion source and a magnetic multipole line cusp ion source has been measured by magnetic deflection mass analyzer. After passage of 90% equilibrium neutralizer cell, the ion beam contains 1%–2% light impurities (such as C+, O+, H2O) and 0.02%–0.15% heavy impurities (such as Cu+, W+, Ag+). Taking into account the neutralization efficiency, the neutral beam is estimated to contain 3%–6% light impurities and 0.04%–0.3% heavy impurities. The impurities related to oxygen decrease with time during a 10 s pulse, while those related to carbon, copper, and tungsten increase slightly with time. The origin of these impurities is discussed and the source operation mode to reduce the impurity level is proposed for neutral beam injection.

ISSN:0034-6748    

DOI:10.1063/1.1136439

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A pulsed molecular beam source has been developed using a conventional car fuel injector and an especially designed vacuum chamber. Beam pulses of about 150 &mgr;s duration (FWHM) and peak intensity better than 1020mol sr−1s−1have been achieved for nitrogen. A simple model explaining the behavior and features of this source is proposed and a comparison with experimental data is presented.

ISSN:0034-6748    

DOI:10.1063/1.1136454

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Modified FM–CW radar techniques using swept millimeter–wave oscillators are useful for determining when a particular density has been reached in a plasma. Narrowband measurements on the Princeton Large Torus (PLT) demonstrate the suitability of these techniques for controlling high‐power auxiliary plasma heating systems. Broadband measurements using these same techniques are proposed, by which the density profile could be determined.

ISSN:0034-6748    

DOI:10.1063/1.1136422

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Design and parameters of the photoionization quantometer are given. It is a combination of photoionization chamber with time‐of‐flight mass spectrometer. The quantometer is an absolute detector of radiation in the wavelength interval (100–0.1 nm) due to the fact that photoionization and electron‐impact ionization cross sections of gases are used for absolute measurements. The quantometer is suitable for measurements of the number of photons in radiation pulses. The minimum number of photons detectable for a single pulse increases from 106cm−2puls−1at 100 nm up to 1011cm−2puls−1for 0.1 nm. The quantometer has been used for vacuum ultraviolet and soft x‐ray radiation measurements in the laser plasma experiment. An improved variant of the quantometer is presented which provides the absolute measurements of soft x‐ray radiation for laser plasma having continuous spectrum. The inaccuracy of measurements does not exceed 25% for soft x ray.

ISSN:0034-6748    

DOI:10.1063/1.1136438

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Due to problems caused by multiple reflections in the cavity walls of the EBT fusion research device, the use of a horn becomes important for the directivity of waves in the millimetric range. An ordinary dielectric lens cannot be used because of plasma–wall interactions. Microwave metallic lenses, designed to focus the energy into a plane wave, can improve the directivity considerably. By implementing a 70‐GHz standard‐gain horn with a delay‐type hyperbolic lens, which consists of a solid metallic disk with a number of equal size small holes, a gain of 15 dB over the no lens case was realized.

ISSN:0034-6748    

DOI:10.1063/1.1136440

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The construction of a mass and energy analyzer applicable for studies of ion streams generated by plasma focus facilities is presented. An appropriate ion extractor (skimmer) system is described. A simple calibration method of the device is also given.

ISSN:0034-6748    

DOI:10.1063/1.1136441

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

An optical system has been developed which allows measurement of light absorption at a given wavelength in the column of a free burning electric arc by comparison of the direct and back reflected light intensities. The difficulties arising from arc movements are avoided by using a corner cube reflector.

ISSN:0034-6748    

DOI:10.1063/1.1136442

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We describe the design, construction, and operation of a new type of microwave spectrograph which allows the measurement of the resonant transitions of transient or otherwise short‐lived species. The spectrograph is composed of three parts: a Fabry–Perot cavity, a pulsed supersonic nozzle as a source for the sample, and the pulsed microwave Fourier transform method. Following a detailed discussion of the three above components in the spectrograph, the operation of the entire system is described and several examples are given.

ISSN:0034-6748    

DOI:10.1063/1.1136443

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A computerized inelastic electron tunneling spectrometer designed for use in practical analyses is described. Spectra are obtained by measuring the first derivative of current vs voltagg using a first harmonic detection technique and then calculating the second derivative using a linear least squares fit of the first derivative segments. This method provides convenient qualitative and quantitative comparisons with conventional infrared spectra.

ISSN:0034-6748    

DOI:10.1063/1.1136444

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A design of a diamond anvil cell is described where a single crystal of sapphire is used for the backing of one anvil with the advantage of an enlarged aperture at an extended pressure range. The selection of diamond anvils with low luminescence at excitation with the Argon Ion laser is discussed. Procedures to control the stresses in samples at very high pressures are given and illustrated by Raman spectra of D2O.

ISSN:0034-6748    

DOI:10.1063/1.1136445

出版商:AIP    

年代:1981

数据来源: AIP