摘要:

We examine the transmission characteristics of spherical plate electrostatic analyzers, for external particle sources, as functions of angular coordinates &agr; and &bgr;, and particle energyE. The angle &agr; is in the plane of the particle's trajectory; &bgr; is in the plane containing the point of incidence and perpendicular to the radius vector from the center of electrostatic force. We express the total energy‐geometrical factorF, which is the ratio of transmitted particle flux (particles/sec) to directional intensity (particles/cm2·sec·sr·keV), in the functional formF≡G&agr;&bgr;EA&bgr;0&Dgr;&agr;&Dgr;E,where &bgr;o, and &Dgr;&agr; are angular parameters and &Dgr;Ethe energy resolution, all appropriately defined. We give methods for determining the functionGand present some specific examples. We show thatGis of the order of unity. A surprising result is that &bgr;o, which is a measure of the angular aperture in &bgr; space, may differ appreciably from the value expected intuitively on the basis of the angular dimensions of analyzer plates. The angles &agr; and &bgr; are locally defined with respect to each arbitrary point of incidence within the entrance aperture. We also give a general method for finding the detailed angular response of spherical plate analyzers in a frame of reference fixed with respect to the analyzer plates.

ISSN:0034-6748    

DOI:10.1063/1.1684022

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A microwave technique for measuring the permittivity and electrical conductivity of shock compressed fluids is described. The results of experiments on carbon tetrachloride are presented and compared with previous work. The technique has a range of 1 to 104in relative dielectric constant and 4×10−5to 4×102&OHgr;·cm−1in conductivity.

ISSN:0034-6748    

DOI:10.1063/1.1684023

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A technique is presented for taking color photographs on the electron microbeam probe analyzer. The procedure involves the multiple exposure photography of a white beam CRT tube using various color filters to create artificially any desired color.

ISSN:0034-6748    

DOI:10.1063/1.1684024

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

An optical carrier, single‐channel telemetry system is described. It provides complete electrical isolation between data acquisition instrumentation and data storage or recording facilities. The system, which has a bandwidth from dc to 50 kHz, has been used successfully in a shock tube facility where high voltage isolation is required for protection of instrumentation.

ISSN:0034-6748    

DOI:10.1063/1.1684025

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A computer method is described for making after‐the‐fact adjustments for incorrect zero energy intercept and instrumental gain to experimental gamma ray pulse height spectra from NaI (Tl) scintillation spectrometers. The method makes use of the 0.511 MeV annihilation peak and 1.46 MeV40K photopeak as internal energy reference standards, both of which peaks are available to NaI (Tl) scintillation detectors. The technique has been tested experimentally and appears to be of practical use for routine energy standardization of long counting time gamma ray spectra between 0.1 and 2.0 MeV.

ISSN:0034-6748    

DOI:10.1063/1.1684026

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A simple instrument for the remote sensing, magnetic recording, and linear display of temperature is described, which is well suited for synchronous recording of temperature and dependent phenomena. A range of 40°C is displayed both during recording and playback, accuracy and resolution being a fraction of a degree. No recalibration or adjustments are needed. Small power consumption (30 mW from a single battery) suggests field uses, possibly unattended. Construction is easy and standard components are used throughout.

ISSN:0034-6748    

DOI:10.1063/1.1684027

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Accurate low temperature Seebeck measurements are difficult since they require the detection of very small emf's. An alternative Peltier measurement, which provides equivalent information, is described, and satisfactory experimental results are presented on materials with Seebeck coefficients as low as 2×10−8V/K. The technique has the capability of measuring a Seebeck coefficient of 10−9V/K with 2% precision and should be particularly useful for use on high resistivity alloys and for measurements in the presence of a magnetic field.

ISSN:0034-6748    

DOI:10.1063/1.1684028

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A high pressure viscometer is described capable of measuring viscosities over the range 1 to 104P at pressure to 3500 kg/cm2and at temperatures between −60° and 100°C. The device is constructed from commercial high pressure tubing and is mounted in a commercial thermal air bath. Calibration is made at atmospheric pressure with the liquid under test against a series of Canon‐Fenske viscometers. Accuracy of the measurement is better than 1% at all viscosities in the range of the device.

ISSN:0034-6748    

DOI:10.1063/1.1684029

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A method is described that can be used for the determination of the heat capacity of a metal (or a semiconductor) as a function of pressure and temperature. The method involves use of a dc electric pulse. If a constant currentIis passed through a wire sample of resistanceR, the heat capacityCpis related to the increase in temperature by the expressionCp=I3RR′/(dE/dt)t=0,whereR′ is the temperature derivative of the resistance, and (dE/dt)t=0is the limiting value of the time rate of change of the emf across the sample. Data are given for iron to 100 kilobars in the temperature interval from 77 to 300 K. The results obtained are in accord with earlier theoretical estimates. The Curie temperatureTcof gadolinium has also been determined from heat capacity measurements; its rate of change with pressure was found to bedTc/dP=−1.3 K/kilobar. With the equipment that is available at the present time, the measurements can be made as long as the specific resistance is 5 &mgr;&OHgr;·cm or greater.

ISSN:0034-6748    

DOI:10.1063/1.1684030

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

A high energy electron beam monitor which detects the Cˇerenkov light emitted in nitrogen gas at atmospheric pressure is described. The monitor is designed to have a constant sensitivity to electrons of energies above 200 MeV, to have a response time of less than 10−7sec, and to have a current output which is linearly proportional to the beam intensity over a range of five decades. The results of tests made on the monitor are presented. The tests show that the monitor has a sensitivity, speed, range, and lack of dependence on beam position and background radiation which make it ideal for many monitoring applications.

ISSN:0034-6748    

DOI:10.1063/1.1684031

出版商:AIP    

年代:1969

数据来源: AIP