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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
Evidence For a T = 0 Resonance in the Z[ ] System (open access)

Evidence For a T = 0 Resonance in the Z[ ] System

In previous letters we have reported a Av resonance, called Y*1, observed through the study of the interaction of 1.15-Bev/c K* mesons in hydrogen in the Lawrence Radiation Laboratory 15-in. bubble chamber. We now wish to report the results of the study of the three reactions [formula](1), [formula](2) and [formula](3).
Date: April 28, 1961
Creator: Alston, Margaret H.; Alvarez, Luis W., 1911-1988; Eberhard, Phillippe; Good, Myron L.; Graziano, William; Ticho, Harold K., 1921-2020 et al.
System: The UNT Digital Library
The [Sigma/Alpha] Branching Ratio Of [Y*1] (open access)

The [Sigma/Alpha] Branching Ratio Of [Y*1]

Recently a T=1 resonance in the [Alpha w] system called [Y*1] has been observed with a mass of 1385 Mev. Two types of resonances have been predicted that might relate this observation to other elementary-particle interactions: (1) P 3/2 resonances in the Alpha w and Sigma w systems predicted by global symmetry corresponding to the (3/2, 3/2) resonance of the wN system, (2) a spin-1/2 Y-w resonance resulting from a bound state in the KN system. The position and width of the observed [Y*1] resonance agree with both theories but since the spin and parity have not yet been determined, it is impossible at present to distinguish between the two theoretical interpretations.
Date: April 25, 1961
Creator: Alston, Margaret H.; Alvarez, Luis W., 1911-1988; Eberhard, Phillippe; Good, Myron L.; Graziano, William; Ticho, Harold K., 1921-2020 et al.
System: The UNT Digital Library
A Sensitive Differential Pressure System For Measuring Cryogenic Liquid Depths (open access)

A Sensitive Differential Pressure System For Measuring Cryogenic Liquid Depths

A system for measuring depths of cryogenic liquids is described. The indicating device is a modified differential pressure gage. The level sensing probes are of various types, either permanent or removable. The heat leak to cryogenic liquids may be made negligibly small.
Date: April 21, 1961
Creator: Pope, William L. & McLaughlin, Edwin F.
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Genetic Influences On Mating Behavior In Drosophila Melanogaster (open access)

Genetic Influences On Mating Behavior In Drosophila Melanogaster

Certain aspects of mating behavior in two different types of Drosophila melanogaster females (Basc and Bv) and wildtype males (Samarkand) have been investigated and compared.
Date: December 6, 1960
Creator: Hildreth, Philip E. & Becker, Gweneth Carson
System: The UNT Digital Library
Data Processing For Bubble Chambers (open access)

Data Processing For Bubble Chambers

The computer program which performs spatial reconstruction of events photographed in a bubble chamber is required to eliminate human and digitizer errors. It recognizes and corrects for single nuclear scatterings in the presence of multiple Coulomb scatterings. Momentum components are determined and kinematic constraints are applied. Measured parameters are performed into special reference frames and quantities of physical interest are calculated. Results are stored in a tape file containing all events of one reaction type.
Date: November 10, 1960
Creator: White, Howard S.
System: The UNT Digital Library
Resistance Measurements To 400 Kilobars (open access)

Resistance Measurements To 400 Kilobars

A modification of the Bridgeman anvils is described. This modification permits studies to be made to a load of 400 kbars, about twice that previously available.
Date: November 8, 1960
Creator: Vaisnys, Juozas; Stromberg, Harold & Jura, George
System: The UNT Digital Library
Photoproduction Of Neutral Pions As A Function Of Mass Number (open access)

Photoproduction Of Neutral Pions As A Function Of Mass Number

The relative yield of neutral photopions from various elements was determined as a function of the quantum limit energy of the Berkeley synchrotron. Single decay photons from neutral pions were observed at 45, 90, and 135 deg to the incident bremsstrahlung in the laboratory system. Mean free paths for neutral pions in nuclear matter were obtained, an optical model prediction of the photopion yields based upon pion-nucleus scattering data was confirmed, and the presence of coherent pion production in the forward direction was detected.
Date: November 4, 1960
Creator: Anderson, John D.; Goodwin, Lester K. & Kenney, Robert W.
System: The UNT Digital Library