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Current-Switching Circuitry (open access)

Current-Switching Circuitry

This paper discusses a group of high-speed switching circuits using the basic current-switching mode of operation. The first part of the paper presents a dynamic analysis of the basic current-switching mode and the second part is the dynamic and steady-state analysis of a current-switching flip-flop.
Date: July 17, 1961
Creator: Salvador, Jack Gilbert & Pederson, D. O.
System: The UNT Digital Library
Reference Manual For KICK IBM Program (open access)

Reference Manual For KICK IBM Program

This reference manual describes the IBM 704 program called Kick, by which complete bubble chamber events are kinematically analyzed. Kick's input data is the output from the Pang program, which uses raw track measurements to spatially reconstruct the tracks, and fits appropriate curves to them.
Date: May 1961
Creator: Rosenfeld, Arthur H., 1926-2017
System: The UNT Digital Library
Antiproton-Nucleon Cross Sections From 0.5 To 1.0 Bev (open access)

Antiproton-Nucleon Cross Sections From 0.5 To 1.0 Bev

Antiproton-production and nucleon-interaction cross sections were investigated for antiprotons in the energy range 0.5 to 1.0 Bev. The antiprotons were distinguished from other particles produced at the Bevatron by a system of scintillation- and velocity-selecting Cerenkov counters. The excitation function and momentum distribution were recorded for antiproton production in carbon and compared with statistical model expectations.
Date: December 12, 1961
Creator: Elioff, Tommy; Agnaw, Louis; Chamberlain, O. (Owen); Steiner, Herbert M.; Wiegand, Clyde (Clyde Edward), 1915-1996 & Ypsilantis, Tom
System: The UNT Digital Library
Energy Response And Physical Properties Of NTA* Personnel Neutron Dosimeter Nuclear Track Film (open access)

Energy Response And Physical Properties Of NTA* Personnel Neutron Dosimeter Nuclear Track Film

This paper reports the chemical and physical properties of the NTA film packet. It correlates with these properties the response of this packet to neutrons of various energies. In this correlation the concept of the track unit is introduced as a basic unit for reporting film-packet response.
Date: January 13, 1961
Creator: Lehman, Richard L.
System: The UNT Digital Library
An Adiabatic Motion Of Charged Particles In Electromagnetic Fields (open access)

An Adiabatic Motion Of Charged Particles In Electromagnetic Fields

The guiding center motion and the adiabatic invariants of charged particle trajectories in electromagnetic fields are treated in this review. General and specific theories of charged particle motion are also reviewed.
Date: January 1961
Creator: Northrop, Theodore G.
System: The UNT Digital Library
Instrumentation Of Multi-Channel Counting Experiments (open access)

Instrumentation Of Multi-Channel Counting Experiments

Recent experience in instrumentation of several nuclear-physics experiments has demonstrated the feasibility of automating the data-acquisition phases of the experiment. Electronic circuits are employed wherever the rate of data flow would be slowed by the use of human operations. Information is selected, temporarily stored, and then recorded in a form suitable for immediate entry into a computer. Experimenters thus freed from the tedious aspects of data collection can devote their time to studying the results of the experiments. Potentially useful nuclear events are first selected by the fast-logic part of the instrumentation. Circuits performing simple logical functions are packaged in modular form for easy grouping into particular coincidence, gating, and mixing configurations. Circuits with slower response times are used for temporary storage and recording operations. Automatic test routines are used to initially align the equipment as well as provide continuous calibration during the experiments. Some of the high-speed circuits are described as well as the methods used to incorporate them into a large counting system.
Date: April 4, 1961
Creator: Kirsten, Frederick A. & Mack, Dick A.
System: The UNT Digital Library
Decay-Energy Systematics Of The Heavy Elements (open access)

Decay-Energy Systematics Of The Heavy Elements

Figures 1 and 2 summarize total decay energies for the four radioactive series. The alpha-decay energy obtained by measuring the energy of the alpha particle leading to the ground state includes the energy of the recoil nucleus. The curve shown in figure 3 defines in broad outline the conditions and regions of alpha instability. A great deal more is to be learned from a more detailed examination of the region where alpha radioactivity is prominent. Of great value to the experimentalist is that he is able to predict alpha energies, and the agreement between predicted and measured values often serves as a criterion for isotopic assignment. A number of systems for correlating alpha decay energies have been employed, and that perhaps most widely used is illustrated in figure 4. Here the isotopes of each element on a mass number vs. energy plot are joined, resulting in a family of curves which over a wide region comprise a series of nearly parallel lines.
Date: January 17, 1961
Creator: Perlman, Isadore & Asaro, Frank
System: The UNT Digital Library
Electrical Limitations To Energy Resolution In Semiconductor Particle Detectors (open access)

Electrical Limitations To Energy Resolution In Semiconductor Particle Detectors

Based on the assumption that the noise contribution of a semiconductor detector is due solely to the bulk properties of the semiconductor, equations are presented which indicate the theoretical limits of noise in detector-amplifier combinations. These equations show that an optimum amplifier time constant and detector bias voltage exist for which condition the minimum noise is independent of the semiconductor resistivity. The optimum performance of a detector-amplifier system is shown to depend only upon detector area, input capacity (less detector capacity), semiconductor minority carrier lifetime, and the transconductance of the amplifier input tube. A new detector structure including a guard-ring electrode as an integral part of the detector structure is described which largely eliminates noise due to surface leakage. Experimental results for detector leakage and energy resolution are presented which agree well with theory.
Date: April 5, 1961
Creator: Hansen, William L. & Goulding, Frederick S.
System: The UNT Digital Library
Kinematics And Dispersion Relations For General Production Processes (open access)

Kinematics And Dispersion Relations For General Production Processes

The method of dispersion relations has in recent years found a wide application for the study of elementary particle reactions. Most of the work, however, deals with reactions of the type [formula], while the theory of those with more than two particles in the final state is still in a very preliminary stage. One reason for this is that even with only three particles in the final state the theory is already much more complicated. Nevertheless, a further development of the theory seemed to us very desirable. The theory at present is being developed on various levels simultaneously. Generally speaking, the aim of this paper is to put the theory in a form as closely as possible analogous to Mandelstam's formulation of the theory of reactions of type [formula]. In the later sections we specialize on reactions [formula], but as much as possible the formulation is in more general terms.
Date: February 2, 1961
Creator: Kretzschmar, Martin
System: The UNT Digital Library
Orbital Radii, Bond Length And Resonance (open access)

Orbital Radii, Bond Length And Resonance

The radius of a c-p hybrid orbital has been found to be given by the expression: [formula] where A is the radius of the pure p orbital, B, a universal constant equal to 0.336 A, and [ ], the coefficient of mixing in the hybrid s + [ ]. When radii appropriate for the orbitals that are paired together are used, bond length is additive of the orbital radii and no Schomaker-Stevenson correction is necessary. This shows that most bonds can be treated as covalent, single and localized.
Date: February 1961
Creator: Somayajulu, G. R.
System: The UNT Digital Library
Effects Of A Magnetic Field On Natural Convection In A Toroidal Channel (open access)

Effects Of A Magnetic Field On Natural Convection In A Toroidal Channel

The problem of the natural convection of an electrically and thermally conducting fluid within a long, narrow, vertical toroidal channel centered in a large block of an electrically and thermally conducting solid is analyzed. A uniform horizontal magnetic field is applied to the fluid, and the bottom of the solid block is maintained at a higher fixed temperature than the top. The laminar steady-state single-cell convective motion of the fluid is considered and an approximate solution is found for the heat transfer rate between the bottom and top surfaces of the block in the limiting cases of small and large Hartmann number. A numerical example is given for liquid sodium in which the application of a magnetic field of a few hundred gauss is shown to significantly reduce the rate of heat transfer.
Date: February 1961
Creator: Concus, Paul
System: The UNT Digital Library
Bremsstrahlung (open access)

Bremsstrahlung

An electron can suffer a very large acceleration in passing through the Coulomb field of a nucleus, and in this interaction the radiant energy (photons) lost by the electrons is called bremsstrahlung (also, bremsstrahlung sometimes designates the interaction itself). If an electron whose total energy [formula] traverses matter of atomic number Z, the electron loses energy chiefly by bremsstrahlung. This case is considered here.
Date: February 1961
Creator: Kenney, R. W.
System: The UNT Digital Library
The Infrared Spectra Of Marginally Metallic Systems, Sodium-Ammonia Solutions (open access)

The Infrared Spectra Of Marginally Metallic Systems, Sodium-Ammonia Solutions

The sodium-ammonia solution system permits investigation of an array of compositions spanning the transition from non-metallic to metallic bonding. Reflection spectra in the range 1-20 [ ] were measured for solutions of mole ratio 5.5 to 168 [ ] per Na. The dilute solutions show peaks characteristic of the vibrations of ammonia and a strong peak near 1.5 [ ] which is assigned to the solvated [ ] species. Concentrated solutions show high reflectivity over broad wavelength ranges. The results for nearly saturated solutions are fitted reasonably by the free electron model, but in the range of mole ratio 10-15 a complex array of energy absorption processes of finite frequencies are required to fit the spectra.
Date: February 1961
Creator: Beckman, Tad A., 1936- & Pitzer, Kenneth S. (Kenneth Sanborn), 1914-1997
System: The UNT Digital Library
Bond Energies, Valence State Energies And Resonance¹,² (open access)

Bond Energies, Valence State Energies And Resonance¹,²

Previous attempts to interpret chemical structure in terms of x-electron resonance have been recently criticized. A reinterpretation of the lengths of the C-C bonds in terms of orbital radii has not revealed any effects of x-electron resonance in the ground states of classical molecules such as 1, 3-butadiene, methyl acetylene, etc. Even in a non-classical molecule such as benzene, resonance shortening of the CC bond is only in terms of the strengths of the hybrid orbitals. If the lengths and force constants of the C-C bonds vary with hybridization, so also must their bond energies. If resonance is not important in classical molecules, the heat of atomization of a classical molecule must be given by the sum of either the energies of the bonds or the contributions of the atoms present in it. To test this theory, we have estimated the contributions of some standard carbon atoms, viz., primary, secondary, tertiary, quaternary, trigonal, and diagonal carbon atoms.
Date: February 1961
Creator: Somayajulu, G. R.
System: The UNT Digital Library
Double Meson Production In Proton-Deuteron Collisions. II (open access)

Double Meson Production In Proton-Deuteron Collisions. II

In a previous publication we reported measurements of the momentum spectra of He<sup>3 and H<sup>3 nuclei produced in collisions of 740-MeV protons with deuterium. The He<sup>3 spectrum exhibited an anomaly in the form of a peak in the region corresponding to double pion production. For reactions resulting in a He<sup>3 the two pions (or particle) can be isotopic spin states 0 or 1; if a H<sup>3 nucleus results only 1 = 1 is allowed. We have since repeated the experiment with a new arrangement which enabled us to measure both the He<sup.3 and H<sup>3 spectra with improved resolution and accuracy.
Date: August 1961
Creator: Booth, Norman E.; Abnashian, Alexander & Crowe, Kenneth M.
System: The UNT Digital Library
Dislocation Substructures In Deformed And Recovered Molybdenum (open access)

Dislocation Substructures In Deformed And Recovered Molybdenum

Specimens suitable for transmission electron microscopy have been prepared from bulk polycrystalline molybdenum after tensile deformation and recovery. The resulting dislocation substructures are described. Some tentative conclusions concerning the mechanism of plastic deformation in molybdenum are discussed.
Date: March 1961
Creator: Benson, R.; Thomas, G. & Washburn, J.
System: The UNT Digital Library
Hydromagnetic Ionizing Waves (open access)

Hydromagnetic Ionizing Waves

It is possible to generate a relatively uniform, highly ionized plasma by passing a powerful discharge between electrodes so arranged that the current is forced to flow across an initial strong magnetic field. The magnetic induction due to the discharge causes a bending of the original field. If the discharge is operated with a low-impedance current source, the electric breakdown starts in a limited region near the current-input connections (minimum-inductance path) and propagates as a well-defined front in the manner of a hydromagnetic shock wave. In this paper we analyze the phenomenon as a one-dimensional single-fluid hydromagnetic problem, neglecting dissipation behind the wave.
Date: May 16, 1961
Creator: Kunkel, Wulf B. & Gross, Robert A.
System: The UNT Digital Library
Experiments On Alfven-Wave Propagation (open access)

Experiments On Alfven-Wave Propagation

This paper reports an extension of previous experimental work with Alfven waves. We consider hydromagnetic waves propagating in a cylindrical plasma in a uniform axial magnetic field. The copper tube is filled with highly ionized plasma by an electrically driven switch-on ionizing wave. After the tube is filled with plasma, a hydromagnetic wave is induced by a radial current flow from the small molybdenum electrode to the copper tube. The force produced by this radial current together with the static axial magnetic field displaces the plasma in the azimuthal direction, and a transverse wave is propagated in the axial direction, along magnetic field lines. The transient magnetic field associated with the wave is also in the azimuthal direction.
Date: May 10, 1961
Creator: Wilcox, John M.; DeSilva, Alan W. & Cooper, William S., III
System: The UNT Digital Library
Hydrides Of Germanium, Tin, Arsenic And Antimony (open access)

Hydrides Of Germanium, Tin, Arsenic And Antimony

Volatile hydrides may be prepared from ether solutions by the reaction of the appropriate chlorides with lithium hydroaluminate. In this general method, it is necessary to work with strictly anhydrous reagents and solvents because of the great reactivity of lithium hydroaluminate toward water. The procedures described here are believed to be much more convenient because the reducing agent employed is potassium hydroborate, which is relatively insensitive toward water. Since only aqueous solutions are involved, there are no solvent-purification steps and there is no dissolution or contamination of stopcock grease, etc.
Date: March 1961
Creator: Jolly, William L. & Drake, John E.
System: The UNT Digital Library
Fast Pulse-Amplitude Discriminators (open access)

Fast Pulse-Amplitude Discriminators

Pulse-amplitude discriminators are useful in nuclear counting to separate signals of greater amplitude from a background of unwanted or noise signals of lesser amplitude. As used here, the term "fast" implies circuits capable of responding to pulses between a nanosecond and a microsecond in duration. An ideal discriminator would produce for any incoming signal whose amplitude is greater than a threshold bias level, an output pulse of constant amplitude, duration, and delay with respect to the input signal, regardless of the incoming duration and rate; and for signals less than the threshold, zero output.
Date: March 30, 1961
Creator: Mack, Dick A.
System: The UNT Digital Library
Cyclotrons (open access)

Cyclotrons

The structure and operation of cyclotrons are discussed. Factors limiting cyclotron size and energy are given. Improvements to the basic continuous-wave cyclotron are described, including frequency modulation, strong focusing, and variable-energy facilities.
Date: April 4, 1961
Creator: Smith, Bob H.
System: The UNT Digital Library
Martensite In CU-12.0% AL Alloy (open access)

Martensite In CU-12.0% AL Alloy

Thin foils suitable for transmission electron microscopy have been prepared from bulk specimens of Cu-12.0% Al alloy quenched from 800' C to produce martensite. The martensitic structure consists of long lenticular plates which are twinned on 20-50A scale. The twin planes in the martensite are shown to be [formula]. There is evidence that this structure is ordered as expected for a transformation from an ordered parent lattice. Experiments using a high temperature stage show that the decomposition of the martensite on tempering can be followed directly, but the martensitic transformation did not recur on cooling.
Date: April 1961
Creator: Thomas, G. & Huffstutler, M.C., Jr.
System: The UNT Digital Library
Close-Capture Adsorption System For Remote Radioisotope Chemistry (open access)

Close-Capture Adsorption System For Remote Radioisotope Chemistry

Molecular sieves are synthetic zeolites which, when dehydrated, contain a network of empty pores and cavities that constitute almost 50% of the total volume of the crystals. They have the unique property of adsorbing within these cavities only those molecules that are small enough to pass through the pores of the crystals, Molecular sieves have a very strong affinity for water and other polar molecules. It is this selective property plus their stability and reasonable cost that make them of interest for the application described herein.
Date: August 17, 1961
Creator: Spencer, Neil C.; Parsons, Thomas C. & Howe, Patrick W.
System: The UNT Digital Library
Remote Plastic Bag Passout Unit For High-Level Radiochemical Operations (open access)

Remote Plastic Bag Passout Unit For High-Level Radiochemical Operations

This system presents a method for making remote sealed-bag passouts from a multicurie-level chemistry processing enclosure. In addition, the polyethylene bags are changed remotely without exposing contaminated surfaces while always maintaining a low leak-rate seal. Our system employs an interchange box (the Passout Box) attached to the chemistry enclosure. Integrated with the box is a hydraulically operated jack that raises and lowers the bags, and a welder-cutter for sealing them. A single master-slave manipulator teamed with the above units handles all operations.
Date: August 1961
Creator: Fleischer, E. S. & Parsons, T. C.
System: The UNT Digital Library