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A counter giving high resolution for lightly ionizing particles incident at 45° has been designed and placed in routine operation in an Enge split-pole magnetic spectrograph. Use of a lumped-constant delay line and inclined cathode pickup stripes results in a very compact unit with high transmission; the collection and readout geometry results in virtual elimination of straggling (energy-loss fluctuations) as a source of resolution degradation. Spectra with total line widths less than 0.25 mm fwhm have been observed with 35 MeV protons.

We show that the influence of strongly coupled deuteron channels on proton elastic scattering is large. The effect is to increase the total reaction cross section by an amount which is several times the pickup cross section. The effect is particularly large for light nuclei suggesting a reason for the breakdown of the folding model for these nuclei. We have carried out model calculations which make these results plausible in terms of the deuteron acting as a doorway for proton absorption. The effect on the real potential is considerable for lighter nuclei and consistently repulsive. Results are also presented concerning the applicability of DWBA for pickup and which illuminate the adiabatic model of Johnson and Soper. Uncertainty in very low energy deuteron propagation makes the observation of experimental effects at (p, d) threshold somewhat doubtful.

A multielectrode structure containing integrated junction-FET input stages is described. Photoengraved microelectrodes are utilized to obtain high dimensional precision, small size, and extremely low capacitive coupling between electrodes. The interelectrode capacitance is less than 0.01 pf. The integrated input devices (JFET's) reduce the impedance levels on the recording channels to less than 500 ohms, virtually eliminating crosstalk and stray noise pickup from the system. The n-channel JFET's operate as source-followers from a common 2.5 volt drain supply and have input impedances greater than 100 megohms at 1 kHz. A simple external preamplifier ensures stable operation and easy interfacing with conventional recording and display equipment. Special considerations in the design of low-noise completely integrated input stages for use with metal microelectrodes are discussed in detail. As a result of the low interelectrode coupling in this structure, simultaneous recording and stimulation from closely adjacent areas of brain should be possible with virtually no stimulus artifact.

The coupling of pickup-stripping channels in 3 He elastic scattering has been shown to have a large effect on the elastic cross section at back angles for higher projectile energies. Quantitative treatment of these effects leads to the conclusion that the “deep” family of mass-3 optical potentials is selected by fitting to high energy, back angle elastic scattering data. This is in contrast to recent optical model studies which have concluded that such data can be fit only by using a “shallow” potential. Consistency is now found between those mass-3 potential families required in certain reaction studies and those indicated for elastic scattering.

With its high peak currents, SPEAR II is likely to show transverse coherent oscillations. A closed loop system using the beams as a signal path detects the bunches' center-of-mass motion and reacts on the beams after one machine period with a set of traveling wave electrodes. The detector senses oscillations at the betatron frequency and rejects signals due to equilibrium orbit shifts. The amplifier output is solely determined by the desired gain and the detector noise. Since, for a given machine tune, the system's phase margin can be made 90° by selecting the respective location of the pickup and feedback electrodes, stability is secured for all values of gain. However, one shows that critical damping cannot be obtained except with infinite gain, and that the system's damping rate is strictly equal to the gain per turn. Measurements of the loop gain have been carried out and agree with the observed damping. To date the system has been successful in dealing with injection oscillations and headtail instabilities.

A new microwave SQUID magnetometer is described which employs a thin-film sensor operable at 4.2 K. Both sensitivity and bandwidth are substantially improved over comparable SQUIDS pumped at RF. Flux sensitivity of \Phi_{o}/100,000 rms Hz-1/2has been attained. The corresponding energy sensitivity is E_{\min}=L_{i}I_{\min}^{2}/2 = 2\times10^{-30} J/Hz. measured at the terminals of the input coil. It is argued that this energy sensitivity is the most useful basis on which to compare SQUID magnetometers which differ in inductance. With a 10 cm diam pickup loop, the magnetic field sensitivity is approximately 3\times10^{-12} G/Hz1/2. Signal bandwidths from dc to beyond 100 MHz are observed, limited only by the input circuit. Feedback loop bandwidths greater than one MHz have been achieved, which allow highly linear operation at frequencies greater than 100 kHz and slew rates approaching 10^{7} \Phi_{o} /Second.

The properties of an electric field probe that consists of two mutually perpendicular conductors attached to the end of a long coaxial line are investigated with a view to minimizing the pickup by the cable. The structure is treated as a junction-loaded crossed-wire antenna. Coupled integral equations for the currents are derived and solved approximately. It is shown that the contribution to the voltage across the load can be kept relatively small compared with the contributions by the active elements of the probe if a correct design is maintained. The analysis is carried out specifically for a normally incident plane wave with components of the electric field parallel to both the cable and the elements of the probe.

A non-intercepting, charge-sensitive, sampling beam probe has been developed for use in internal beam phase measurements in the variable-energy, separated sector injector cyclotron at Indiana University. The two probe pickup plates of 10mm by 16mm are located above and below the median plane with sampling diodes in close proximity. The probe head is mounted on a movable assembly permitting continuous observation of phase history from inflection radius through extraction radius, at interval beam currents of 100 nanoamperes or greater with pulse rise times of less than one nanosecond. Over a two-year period the phase probe has proved relatively reliable and easy to use for confirming trim coil adjustments and orbit dynamical isochronization procedures. The probe display, in addition to providing data on phase group width and centroid versus radius, has on occasion shown up ion source ripple and radio frequency parasitic generation which might otherwise have been overlooked.

Theoretical and experimental results are presented of a new color TV camera pickup system using a frequency interleaving method. This system uses not only spatial-frequency encoding techniques, but also color stripe filters inclined to the line scanning direction. Frequency interleaved modulated color signals occupied together in the same frequency bandwidth are obtained as the output signals of the image pickup tube, and are electrically separated by a comb filter.

Conventional high-frequency (HF) circular phased arrays, such as the Wullenweber circular array, have a cost factor that increases at a greater-than-square law rate as its radius is increased to produce larger apertures. A new method of forming simultaneous beams in an HF circular array has been proposed in which beams are formed in the space within the array from pickup element energy that has been amplified and reradiated. Such a device is called a circular active reflector antenna (CARA), and its cost increases at a substantially linear rate as its radius is increased to form larger apertures. This paper describes calculations of the distribution of reradiated energy within such an array in order to study the effect of changes in array configuration. A cost analysis is presented to establish the dependence of array cost on array size for both the conventional and CARA types of arrays. In addition, the performance of an experimental CARA array is reported. An experimental CARA array consisting of a 120\deg partially filled sector of 1500 m radius, forming six beams over a 2\deg field of view was constructed at a site in Utah to demonstrate the feasibility of the concept. Measurements made on the experimental array showed that at 14-MHz, it formed beams 0.7\deg wide at the 3-dB points, which agrees closely to the calculated value. The sidelobe response also compared closely to the level and angular position calculated for the sidelobes of the partially filled sector array tested. No evidence of instabilities or intermodulation distortion was noted.

A method of testing the color separation characteristics of television film cameras as well as other types of television pickup equipment is proposed. A special test target printed on standard color positive film is scanned by the television camera under test. The signals at the outputs of the usual red, green and blue amplifier channels of the camera, resulting from scanning three separate color wedges are compared with the signals obtained at the same outputs from scanning a neutral-density step wedge. Experiments demonstrating the validity of this method are described, and the results of the tests together with an evaluation of the accuracy obtained in this manner are presented.

The beam position system of the Fermilab Main Ring contains one horizontal and one vertical Electrostatic Beam Pickup in each of the 96 cells of the machine. A pair of 75 ohm cables transmits the induced signal from the machine tunnel to the nearest service building. In each of the 24 service buildings, there is a solid-state multiplexer and a beam position detector which processes the A-B signal pairs to produce an intensity-normalized voltage proportional to beam displacement. This voltage is digitized, read into buffer of the Lockheed MAC A, and in turn transferred to the Xerox 530. Horizontal or vertical orbits can be obtained ih 50 millisec. Orbits are obtained at injection, and at a Main Ring Sample time, if requested, anywhere on the acceleration cycle. Injection orbits can be flattened automatically by a program that sets dipole trim magnets.

We have calculated K-shell pickup cross sections using the full first Born approximation developed by Jackson and Schiff for a number of heavy-ion collisions for which experimental data have recently become available. These include protons on argon at a range of velocities and fully stripped ions Z = 1, 6, 7, 8, 9, on argon at three velocities. The calculations attempted to include the effect of screening by target electrons with a crude effective potential. We conclude that the full first Born charge-exchange cross section gives nonphysical results for the systems examined, thus casting further doubt on the theoretical significance of the good agreement with experiment one obtains for protons on hydrogen.

In order to study vibration transmission to the human body and to design seats or suspensions for vibration isolation in the vehicles, a driving point mechanical impedance was measured on various kinds of body postures. A force pickup which was newly developed using a sheet of thin polymer film and an accelerometer were used as a detector for the impedance measurement. An instrument with analogue computing circuits was also employed, which could automatically calculate the im-pendance and draw an impedance chart expressed by magnitude and phase within 90 sec after the start of measurementThe mechanical impedance were measured in the frequency range from 3 to 200 Hz on kneeling, sitting, and standing postures and in addition, at local parts of the body such as the head, hands, and legs. Because of contraction of measur-ing time, the impedances even in unstable postures were able to be measured. As a result, the difference of mechanical impedance was clarified among various sorts of the postures, and transmission mechanism of the vibration in the body could be estimated through the change of the mechanical impedance.

A class of second‐order gradient microphones with unidirectional directivity characteristics is analyzed. These microphones consist of four in‐line sensors whose outputs are added with proper delays. The directivity characteristics of such microphones are rotationally symmetric and given by (α+cosϑ)(β+cosϑ), where α and β are constants and ϑ is the angle of incidence relative to the rotational axis. The calculated maximum directivity factor is 9. Experimental systems consist of an electret transducer enclosed in a cylindrical cavity and four tubes, paired in length, extending from the cavity to sample the sound field. Measurements on a transducer with α=1 and ‖β‖ ≪ 1 yield a sensitivity of about −80 dBV/μbar in the direction of mzximum pickup (ϑ=0) with variations of less than ±3 dB in the frequency range from 0.2 to 4 kHz. The measured sensitivity is about 20 dB lower for ϑ=90, 180 and 270°. Because of their large directivity factors, such microphones are of interest in environments with high noise level...

In this paper, subjective studies made on nonexponentially decaying sounds are described. The various decay conditions are realized by changing the position of the pickup microphone in a reverberation room with a highly absorbing sample on the floor. It is shown, by means of articulation tests, that intelligibility of speech is more close to a highly absorbing sample than away from it. It is also shown that the perception of decay is mainly due to the initial portion of a nonexponential decay. The significance of these studies is determining the acoustics of halls is explained.Subject Classification: 55.20; 70.35; 55.30.

The 41 Ca(d, t) 40 Ca and 41 Ca(d, τ) 40 K reactions have been investigated at a bombarding energy of 40 MeV. A distorted-wave analysis of the measured angular distributions and a sum-rule analysis of the resulting spectroscopic factors has enabled the identification of members of various particle-hole multiplets. Values obtained for the matrix elements of the 1 f 7 2 − 1 d 3 2 −1 effective interaction are in poor agreement with values obtained from other nuclei, but are reasonably well reproduced by calculations with a simple force.

The scattering of nucleons by $sup 16$O is studied with the resonating- group method. The $sup 16$O wave function used is a translationally invariant antisymmetrized product of single-particle wave functions of (1s)$sup 4$(1p)$sup 12$ configuration in a harmonic-oscillator well having an appropriately chosen width parameter. A generator-coordinate technique is employed to facilitate the computation of the nonlocal interaction between the nucleon and the $sup 16$O nucleus. This technique is discussed in some detail in order to demonstrate its utility in a nuclear problem involving a relatively large number of nucleons. Calculated results are compared with experimental data over a wide range of energies, and it is found that the agreement is in general quite satisfactory. Also, the result shows that in this particular problem the heavy-particle pickup process, which is properly taken into consideration by the use of a totally antisymmetric wave function, has a relatively small contribution. (AIP)

A versatile photon and charged particle imaging system is described. The Ranicon employs a microchannel electron multiplier plate to convert each detected event into a charge signal. This charge pulse is proximity-focused onto a large-area resistive anode plate equipped with pickup electrodes on its edges. Each event is located electronically by the ratios of the charges collected at the edges or by the differences of the signals' risetimes. One- or two-dimensional pictures are built up by storing events digitally (e.g., a core memory) or in analog form (e.g., a storage oscilloscope). Compact laboratory models have been constructed and tested. Operating characteristics, applications, limitations, and advantages of the Ranicon are discussed.

In the measurement of turbulent pulsations there arises an error due to averaging over the receiving surface of the pickup. The term “resolving power” is widely used to characterize this error. If the error is small, it is assumed that the pickup has a high resolving power. Starting from the theory of isotropic turbulence and the hypothesis of A. N. Kolmogorov, an evaluation is obtained of the error in measurement of trubulent pulsations of the velocity using a thermoanemometer. The theoretical conclusions are confirmed by experimental results.

A capacity micrometer for the measurement of blade clearance in a turbine is described. The calibration of the instrument is non-linear with displacement, and clearances of the order of .030 to .001 inch may be measured with a nominal accuracy of ± 10 percent of the indicated reading. Measurements may be made at temperatures up to 1500°F. by the use of water-cooled pickup probes, and with a frequency response from DC to 200,000 cycles per second. The stability of the measurement depends on the temperature stability of the pickup dielectric material. Pickup drift may be measured during operation and may be counteracted by a control on the instrument. Stable reference capacitors provide a means for checking zero drift and calibration independent of the pickup and cable. Examples of the application of the instrument to a variety of other displacement measurements are provided.

A hermetically sealed photoelectric drop impulse pickup has been constructed for measuring the volumetric blood flow in veins and arteries by means of the pen-recorder. A miniature semi-conductor photoresistance is used in this pickup. The wiring circuit of the electron amplifier which controls the pen-recorder is presented. The amplifier allows the internals to be registered either between each drop or after every drop and automatically controls the displacement of the recorder pen at regular intervals. The amplifier also registers the frequency of mechanical impulses (heartbeat, etc.) by means of the pen-recorder.

走査線ごとに位相反転するストライプフィルターと, 画像の垂直相関を利用した復調方式を用いた単管カラー撮像方式の提案と特性の検討を行ない, 従来の周波数分離方式より高解像度の像が得られることを示した.次に, 周波数分離方式一般の雑音特性, 色再現性の限界を示し, 3管式との対比を明らかにした.また, 本提案の構造をもつストライプフィルター付のビジコンを用いた白黒なみの小形カラーカメラを試作し, 300本以上の高解像度のカラー像をえた.

The pickup described will track with a vertical force of 2 grams, on simple but properly designed tone arms. It has a mechanical compliance 6 cm × 10-6/dyne and an effective mass of about 1.4 mg. Output is 0.35 volt. A combination of optimum rubber properties and viscous damping provide a response free of resonances. The design is well suited for quantity production for the home phonograph market. Another paper describes successful tracking of this cartridge in commercially available record changers. In a pickup destined for quantity production, several design factors must be met in order to maintain uniform high performance. It is important that the two ceramic elements be correctly positioned during assembly. In the present design this is done by means of octagonal rubber element mounts which are placed into two semioctagonal channels on mating interfaces of two plastic housing parts. In any two-element stereophonic pickup design, a "coupler" is needed to join the two elements to a single stylus arm. Design of the coupler has important bearing on distortion, output level, channel separation, and mechanical impedance. Coupler requirements in the present design have been met by proper configuration and choice of material. Another important design factor is the means provided for pivoting the stylus level arm. For lateral motion, at the stylus, compliance must be high for lateral motion in two degrees of freedom. Rotational compliance, about the lever axis, must be low in order to avoid undesirable rotation of the lever arm. There must be no lateral freedom at the pivot point. Longitudinal compliance of the level arm must be low in the direction of drag from the record groove to avoid frequency modulation effects. The stylus lever mounting arrangement described achieves these design requirements in a simple assembly. A light tube, comprising the lever arm, is flattened at its pivoted end in a manner to produce tapered shoulders. These shoulders are brought to bear against a hole in a small rectangular metal enclosure which is filled with a plastic material having viscoelastic properties. The potting arrangement damps any lever resonances and provides a small restoring force to position the lever for engaging the coupler during change of styli.

A description is given of an apparatus capable of measuring instantaneous voltages in the presence of heavy current discharges. The basic advantages of the system are (1) a single ground connection which is independent of the two points of the desired voltage, (2) cancellation of induced voltages in measuring circuit by electronic means with bandpass depending only upon amplifiers used, (3) the cancellation of the measuring circuit pickup is insensitive to large changes in the geometry of the measuring circuit.

The magnetic-field gradients produced by a current sequentially activating a few turns of wire of a precision solenoid are used to measure its pitch. The position of the activated portion of wire can be resolved to 0.1 ?m. Preliminary results are found to be in agreement with an earlier measurement using a contacting probe to within the uncertainty of the latter determination. This new technique reduces many of the difficulties associated with conventional pitch measuring schemes and at the same time provides a method of obtaining increased accuracy.

The velocity television reproduction system described in this paper uses a combination of standard video principles for image pickup and velocity-modulation methods for picture reproduction. An analysis is presented which indicates the response of the system to a general video signal. It is shown that one form of presentation imparts a three-dimensional appearance to the image. Photographs are presented of standard broadcast television images reproduced on a conventional receiver converted to velocity-modulation reproduction.

An X-band reflex klystron is modified for a highly sensitive pickup sensor for an accelerometer and a seismometer application. Seismometer sensitivity of 460 μJ are recorded with potential accelerometer sensitivity of 2 μg indicated in this preliminary test.

At the present time, both iconoscopes and image orthicons are employed in monochrome television broadcasting for transmission of motion picture film. The theoretical considerations of such operation have been covered quite thoroughly in the literature, while the many practical problems have received very little attention. A discussion of the correlation between the basic theoretical problems of television motion picture film pickup and their practical solutions as presently employed in television broadcasting is given.

The photosensitive layer of the Plumbicon is an evaporated microcrystalline layer of lead monoxide. The most significant advantages of the Plumbicon are the low dark current, the high speed of response, which is independent of light intensity, and the high sensitivity. In the Plumbicon, every picture gives a signal that is dependent solely on the light-intensity projected on that particular picture element within the proper time-limits and is unaffected by disturbing effects known from other pickup tubes. This new tube is expected to prove especially suitable for color television.

A calculation of the forward-angle differential cross section for the reaction $p+A\ensuremath{\rightarrow}(A\ensuremath{-}2)+p+d$ indicates that processes involving nucleons which are uncorrelated when the projectile initially interacts with the target are as significant as those processes involving correlated nucleons.

Stripping and pickup reactions are performed and show the configuration for the lowest 3−state (7.62MeV) to be mainly a hole in the 1p shell the next 3−level (8.36 MeV) is mainly promoted into the 2p-1f shell.

The NAL booster - accelerator radio-frequency system design is described in detail. This rapid-cycling system is ferrite tuned from 30 MHz to 53 MHz. Each high-power module has an RF-output rating of 100 kW provided by a cascode amplifier which is a removable part of the cavity assembly. The low-level portion of the system corrects for both systematic and non-systematic tracking errors using a single set of wide-band beam sensors. In the design of a storage-ring RF system, the control of the beam-cavity interaction is a basic problem. This paper describes an arrange ment of TEM mode cavity, cascode power amplifier, beam pickup and feedback control loop to achieve a cavity-gap impedance of about 10 ohms over a frequency range from the synchrotron-oscillation frequency (a few Hz) to the higherharmonics of the bunch frequency. The design center radiofrequencyis 53.1 MHz.

I. INTRODUCTION The problems of static electricity in the polymer industry are many and varied (see Table 1). They range from the removal of unwanted charge during fiber spinning and processing in order to avoid charging the machine and to reduce handling problems and dust pickup (fog marking), through the physiological problems associated with synthetic fiber carpets and automobiles to the explosion hazards of aircraft refueling, hospital environments, and mines. This is not to imply that all static is bad; in xerography, for example, the latent electrostatic image is developed by using toner (dry ink) charged by tumbling against the carrier; electrostatic separators make use of triboelectrification to accomplish separations not possible by other techniques.

By means of a modification of the pistonphone, a technique has been developed to obtain the response of a capacitance type vibration pickup probe using the reciprocity calibration of a condenser microphone as a reference. The raised, center portion of a circular piston, driven by a barium titanate cylinder, projects into one end of a cavity, the shelf of the piston being located outside of the enclosure. A calibrated condenser microphone coupled to the other end of the cavity responds to the sound pressure developed by the piston. The output of an annular capacitance type vibration pickup, which detects the motion of the piston shelf, is compared with the generated microphone voltage. With the microphone removed from the cavity, the output of a capacitance probe located adjacent to the top surface of the piston is compared with that of the annular pickup. The probe response is computed from these measurements and the microphone response.From considerations of checks by independent methods, an accuracy of ...

A method is described for the measurement of characteristics of pickup electrodes (PUE) for monitoring coordinates of an accelerator beam. A new representation is discussed for determining the coordinates of the center of charge for the entire PUE aperture. A few prototypes of PUE's to be installed in the AGS were tested and the results show that nonlinear deviations are at least 1 mm/25 mm. The method of measurement has a resolution of at least 0.1 mm/25 mm; it can therefore be used for (a) the design of high quality PUE's and (b) calibration of PUE's as installed in the accelerator in order to increase the usable aperture and the accuracy of beam coordinate monitoring.

The production of secondary particles by the passage of cosmic radiation through matter is a well-known feature of the cosmic ray phenomenon. Cloud chamber photographs of Blackett and Occhialini, Anderson, and Kuntze how that the secondaries often occur in groups, which have been named "showers.” The production of those showers was investigated by observing the simultaneous discharges of three Geiger-Müller counters so arranged that hey only recorded showers of at least three particles. The main experiments were carried out at the Forschunga-station Jungfraujoch, in Switzerland, at height of 8800 metres. Other experiments wero made at Eigergletscher (2300 m.) and Zürich (500 m.) to investigate the variation of frequency of the showers with altitude. Experimented Method. The experimental arrangement was similar to that used by Rossi and by Fünfer. Three Geiger-Müller counters were used, arranged as shown in fig. 1. The lead under investigation was placed above in such a position that no particle coming from the lead could go through more than one counter. The triple coincidences due to the presence of the lead must thus be due to showers of at least three particles. The coincidences were recorded by a method described by Rossi. The impulse from a fourth valve was fed to the grid of a thyratron by resistance capacity coupling, fig. 2. This impulse was a negative kick, but the accompanying positive back-kick was sufficient to trip the thyratron. This arrangement rendered the circuit very stable and free from external pickup.