摘要:

An analog computer has been applied to the problem of tracing the trajectories of a beam of charged particles such as is produced by high energy accelerators. The electrical circuit involved employs analogs for both quadrupole magnets and bending magnets, and thus it facilitates the determination of both the focal properties and the dispersion characteristics of the magnets; an accuracy as good as 2% has been attained for some of the calculations made with the present instrument.

ISSN:0034-6748    

DOI:10.1063/1.1716809

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

Visual particle detection methods have been used with high energy bremsstrahlung beams of low intensity. A method for obtaining a substantial increase in the gamma‐ray beam intensity which can be passed through a 9‐in. propane bubble chamber is described. The beam is collimated and then led through a hollow tube passing through the middle of the bubble chamber. It was found that use of a ``beam tube'' increases the number of events observed per picture by a factor between five and ten over the number found with no beam tube. The 300‐Mev bremsstrahlung beam of the MIT synchrotron beam was used for these experiments. Advantages and limitations of the beam tube method are discussed.

ISSN:0034-6748    

DOI:10.1063/1.1716810

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

This paper analyzes an electron paramagnetic resonance microwave bridge spectrometer, and expressions are given for the relation between the signal and the imaginary part of the magnetic susceptibility. From these the conditions for maximum signal are obtained. The analysis is also applicable to many other types of magnetic resonance spectrometers.

ISSN:0034-6748    

DOI:10.1063/1.1716811

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

A special purpose coincidence circuit with millimicrosecond resolution time is described which illustrates the simplicity that can be achieved with transistorized circuits. The circuit performs all the logical operations of three simultaneous experiments to measure the branching ratio to the electronic mode of pion decay. Performance data under operating conditions on the cyclotron are given.

ISSN:0034-6748    

DOI:10.1063/1.1716812

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

An experiment is described in which a beam of fast neutral atoms was injected into the terminal of a tandem accelerator. A second tandem was arranged in line with the first. By taking advantage of charge‐exchange mechanisms these atoms were accelerated to 15 Mev by a three‐stage process.

ISSN:0034-6748    

DOI:10.1063/1.1716813

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

This report describes the design and testing of a 1.17‐Bev/c separated K−beam designed in the fall of 1958 in connection with a 15‐in. hydrogen bubble chamber experiment. At the target the K−/&pgr;−ratio was 1/140. At the chamber, 4.0 K−‐meson decay lengths from the target, and after two stages of electromagnetic separation, the K−/&pgr;−ratio was 12.5, corresponding to a total pion suppression by a factor of about 105. The K−flux at the chamber was 0.87 K−mesons per 1010protons impinging on the target.

ISSN:0034-6748    

DOI:10.1063/1.1716814

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

A method is described for measuring neutron spectra in the energy range 1 to 10 Mev. The pulse‐height spectrum of scintillations produced in a stilbene crystal by recoil protons originating in the crystal is analyzed to yield the incident neutron energy distribution. Insensitivity to gamma rays and electrons is achieved by utilizing differences in the pulse shapes of light pulses produced by electrons and protons. This spectrometer is useful for both group and continuous spectra and has been tested by measurement of the spectra from a Pu‐Be neutron source and from the spontaneous fission of Cf252. Both measurements are consistent with previous data. The Pu‐Be data definitely confirm a peak at 9.7 Mev that was suggested by previous data.

ISSN:0034-6748    

DOI:10.1063/1.1716815

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

The instrument described provides rectangular pulses separated from ground by less than 20 pf capacity and essentially infinite resistance. The transistor switch provides pulses at low output impedance, from a floating battery, of 0 to 80 v in amplitude and variable in duration by the width of a triggering stimulus from a conventional stimulator or pulse generator. The device is of particular use in biological experiments where isolation of a stimulating pulse from ground is required.

ISSN:0034-6748    

DOI:10.1063/1.1716816

出版商:AIP    

年代:1960

数据来源: AIP

摘要:

An instrument for transferring information from a magnetic core memory to punched paper tape is described. When used with a 100‐channel pulse‐height analyzer with a capacity of 105counts per channel, total readout time for all 100 channels is less than 17 sec.

ISSN:0034-6748    

DOI:10.1063/1.1716817

出版商:AIP    

年代:1960

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1716818

出版商:AIP    

年代:1960

数据来源: AIP