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.

Experiments with a simple pulsed magnetic field in cusped geometry are described. The plasma is generated inside the containment region rather than injected from an external source. It was found that creation of the plasma by a linear pinch discharge is most successful. Only qualitative studies have been carried out so far, using time-resolved visual observation of the plasma. Well-defined plasma bodies located in the central region between the cells were photographed. In order to make them clearly visible, a few percent of argon was added to the hydrogen.

This bibliography is selective, unclassified, and covers the period 1950 - April 1960. Sources consulted were the following: Applied Science and Technology Index (Industrial Arts Index), Chemical Abstracts, Engineering Index, U.S. Atomic Energy Commission Nuclear Science Abstract, Armed Services Technical Information Agency Title Announcement Bulletin, and Publisher's Catalogs.

The increasing exponential function e-at [a > 0] characterizes such natural events as gas discharges, neutron multiplication, and the transistor avalanche phenomenon. This report describes an instrument for measuring the rate of rise, a, of an increasing electrical exponential signal.

The increasing popularity of liquid-hydrogen targets in physics research has emphasized the need for containers with maximum beam transparency (i.e., thin walls and low Z) and suitable strength at cryogenic temperatures. Fabrication of a Mylar container satisfying these requirements is described here.

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.

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.

In November 1952 an event took place which was to have a profound effect on political alignments of the world. This event was the detonation of "Mike", the first large thermonuclear device. The political implications of this experiment overshadowed what has come to be a major advance in the development of scientific tools; the experimentally verified, extremely high thermal neutron flux observed in Mike. Subsequent to this observation, the Atomic Energy Commission established a study program to investigate this particular characteristic of nuclear devices. Under the program, Los Alamos Scientific Laboratory and Lawrence Radiation Laboratory, Livermore, have studied the mechanisms of high fluxes, capture systematics, general stability characteristics, and more specifically, nuclear design to accomplish this massive neutron irradiation. Utilization of these greatly increased fluxes can be expected to significantly advance understanding in many fields.

The most important component required for the Astron experimental facility is a high energy, high current, pulsed electron accelerator. A thin cylindrical layer of high energy electrons trapped within an axially symmetric magnetic field is the key feature of the Astron thermonuclear device. The trapping magnetic field is constant in time. Therefore, it is not possible to inject electrons and trap the electrons in this field unless during the injection phase a part of the electron energy is absorbed by some friction process. This is accomplished by means of eddy currents generated on suitable passive circuits by the current of the injected electron bunch. This method has ben described elsewhere. However, in order to achieve an effective loss mechanism the current of the injected electron beam must be over one hundred amps. Such high current beams are difficult to handle except if the electron energy is high enough so that the electrostatic repulsive force is compensated to great extent by attractive magnetive forces. Hence the electron energy required is 5 Mev or higher. Other requirements on the electron layer yield the same result.

Previous studies have been made of the relationship among acceleration, specific power, payload fraction, and travel time for many interplanetary missions. These utilized tangential thrust and correspond to the high thrust Hohmann transfer orbits. In addition, a complete optimization of the one way Mars mission has been accomplished. Since the minimum Jupiter round trip time was six and a half years for tangential thrust, calculations were carried out using higher energy transfer orbits. It is shown that the orbit-matching problem cannot be solved with tangential thrust programming in this case. The initial period of acceleration away from the earth's orbit was accomplished using tangential thrust in order to minimize energy expenditure. This was followed by a period of coasting until the proper moment arrived for commencing the orbit-matching maneuver. This terminates when the velocity and spatial coordinates of Jupiter's orbit are matched. The technique used for accomplishing these various orbit matching conditions without iteration are described. Best results for the final maneuver were obtained with the thrust vector approximately normal to the velocity vector. By this technique it is shown that the round-trip Jupiter mission may be carried out in four and an half years with 16% payload and 0.10 …

The theoretical half lives for alpha emissions have been calculated for nearly all of the complex alpha spectra. The spin independent equations of Preston were used for the calculations. The nuclear radius for the even-even nuclei was determined with the assumption that the alpha transition to the ground state is unhindered. For odd mass nuclides the average of the nuclear radii of the adjacent even-even nuclides was used. For odd-odd nuclides the average of the nuclear radii of the adjacent odd mass nuclides of the same atomic number was used.

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.

One of the techniques by which highly ionized plasmas can be generated in the laboratory makes use of strong, electromagnetically driven shock waves propagating into a cold gas. In this paper the phenomenon is analyzed as a one-dimensional single-fluid hydromagnetic problem, neglecting dissipation behind the wave. We hypothesize that the rarefaction wave remains attached to the front. In the limit of essentially complete ionization behind the front the problem can be solved analytically as long as the transverse magnetic field there remains small compared with the longitudinal field.

One of the techniques by which highly ionized plasmas can be generated in the laboratory makes use of strong, electromagnetically driven shock waves propagating into a cold gas. In this paper the phenomenon is analyzed as a one-dimensional single-fluid hydromagnetic problem, neglecting dissipation behind the wave.

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.

Report issued by the University of California Lawrence Radiation Laboratory discussing a method of updating library circulation records on an IBM 1401 computer. The report describes the methods of generating and updating the records using transaction cards to create computer tapes that are sorted and updated to prepare current reports of circulation information.

Introduction. A survey has been made of the image converter tubes generally available in this country and Europe. Ultraviolet and infrared types using photocathodes were included, buy x-ray and solid state types were omitted. Since this is the first time that this list has been compiled, it may have errors and omissions. The author will appreciate any corrections or suggestions, and it is hoped that revised lists will be published from time to time.

Females heterozygous for a wildtype X chromosome from a Samarkand stock and an chromosome of the composition [formula] were tested for the frequency of X-chromosomal non-disjunction and segregation of the X's when Y chromosomes of different types were present in the females. The Y chromosomes used were 1) a normal unmarked Y, 2) [formula], 3) [formula] and 4) [formula] (a chromosome which arose in one of our experiments and has not yet been analyzed). Since this was only a preliminary test no attempt was made to isogenize the stocks. Larger scale experiments are planned in which these and other Y's will be used and the genetic background will be strictly controlled.

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.

The following report describes the injection and trapping of high current electron beams in order to construct an electron gun and the first 2 Mev section of the accelerator.

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.

Presented herein is a philosophy for designing wideband multistage transistor amplifiers. The amplifier is visualized as an integral unit, the interstage networks constituting the elements of the amplifier unit. By designing the amplifier as a unit and adjusting the overall response (gain and bandwidth) with the interstage time constants, an increase in gain-bandwidth product is realized over the iteratively designed amplifiers. The resulting increase in gain-bandwidth product results from absence of the bandwidth shrinkage factor for multistage amplifiers. Formulas are derived for both a two- and three-transistor integrally designed wideband amplifier, in which shunt peaking networks are used for coupling. Experimental amplifiers were constructed following these formulas, and the observed performance agreed quite well with the calculations.

This report is a corrected copy of the authors "rapporteur talk" at the 1959 Kiev Conference on High Energy Physics. It contains data on the rapporteur system and on interactions of strange particles with protons and neutrons, using data from bubble chambers, counters, and emulsions.

Both in magnetohydrodynamic shocks and in accelerated partially ionized gas flow across a magnetic field, space charge separation occurs that establishes very large electric fields in the direction of motion. The width of the current layers associated with the acceleration is never less than the electron Larmor radius with no collisions and is broadened by electron collisions to a width solely determined by the effective resistivity. The electrons gain an energy regardless of collisions equal to the electric potential difference across the layer. This potential corresponds to the change in kinetic energy of mass motion per ion. For slightly ionized gases, the additional stress of neutral ion collisions within the layer can make the electric potential and hence gain in electron energy very large for only modest changes in mass velocity. Hence ionization may occur when the change in kinetic energy of the ions is small compared to the ionization potential.