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Optimum relocation of the brake relative to the accelerator can reduce stopping distance and may mean the difference between an accident and a near-accident. A driving simulator was used to examine efficiency of braking movement time. Movement times were measured for 60 participants (30 male, 30 female) in six different depth/lateral-separation conditions. Movement times were shown to improve as a result of moving the brake pedal from its typical heights above the accelerator to positions equal with and below the accelerator.

Differential cross sections for $\mathrm{dp}$ elastic scattering from 60\ifmmode^\circ\else\textdegree\fi{} to 175\ifmmode^\circ\else\textdegree\fi{} center of momentum (c.m.) were measured at 3.43, 4.50, 5.75, and 6.60 $\frac{\mathrm{GeV}}{c}$ incident deuteron momentum. The measurements were made with a two-arm magnetic spectrometer, making use of multiwire proportional chamber detectors. The deuterons were accelerated at the Bevatron of the Lawrence Berkeley Laboratory. Data are compared with predictions of the baryon-pickup model and the one-pion-exchange model. The backward dip at 180\ifmmode^\circ\else\textdegree\fi{} c.m. for 4.5 $\frac{\mathrm{GeV}}{c}$, predicted by Craigie and Wilkin using the one-pion-exchange model, is not observed, but reasonable fits to the momentum variation and angular distributions are found. When the data are plotted against the variable $\ensuremath{\Delta}$ of the baryon-pickup model, the $s$ dependence is greatly reduced.

A study has been made of the visible breakdown plasma produced by focusing single TEA CO2 laser pulses 200 nsec wide with salt lenses of 16‐ and 22‐cm focal lengths in argon, helium, neon‐helium, and nitrogen at pressures up to 11 atm. Pulse energies ranged from 0.9 to 11 J, with a maximum intensity at the 1‐mm focal diameter of 6.6×109 W/cm2. At this incident intensity, well above the breakdown threshold, the main breakdown plasma in argon occurred well upstream of the focus and its multiple structure extended over 5–9 cm. In the focal region only a few isolated sparks were seen. At incident powers closer to threshold, the breakdown occurred closer to, or at, the focus, and migrated upstream toward the laser as the pressure was increased. The spatial structure of the breakdown plasma as seen by time‐integrated photography, and the temporal development, monitored by photon drag observations of the transmitted power pulse, were studied with various gases, pressures, and incident pulse energies. A description of the breakdown process is offered which accounts for many of its features, especially the absence of breakdown in the focal region.

The problem of chemical order of polyamide-hydrazides prepared from terephthaloyl chloride with an unsymmetrical monomer, p-aminobenzhydrazide, is discussed. An NMR method for identifying the molecular structure of species formed in the early stages of poly condensation has enabled the course of a polymerization to be followed during this time and the final degree of order to be predicted qualitatively. These studies have provided a demonstration that the structure of these polymers can be controlled to a significant degree by appropriate variations in experimental conditions. But even under the most adverse conditions usually employed, poly amide-hydrazides are found to be at least “partially ordered” copolymers. The techniques developed for this study may find application in the study of other polymer forming reactions with monomers having two functional groups with dissimilar reactivities.

Spark gap overvoltages of fast Marx generators in the 100-300 kv range were studied as a function of stray and interstage capacitance for several circuit designs. Overvoltage measurements were made at low voltages by simulating the spark with a silicon-controlled rectifier. Breakdown times were measured to nanoseconds by viewing the light flash from the sparks with a fast photomultiplier. The influence of the ultraviolet irradiation on breakdown time was studied by masking the first gap. Practical conclusions for Marx generator design are presented.

A novel method based on NMR for the characterization of oligomers formed by the reaction of terephthaloyl chloride with excess p-aminobenzhydrazide is presented. These studies have provided significant insight to the “ordering process” or “self-regulation” involved in corresponding polymerization reactions.

A study has been made of the reaction\(\gamma + p \to \pi ^ - + \mathcal{N}^{ * + + } \) using a polarized X-ray beam. The essentially null result obtained for the production asymmetry can assist in determining the OPE contribution to this reaction.

Gain‐switched CO2 laser pulses of 225 J were focused onto planar carbon targets in the presence of longitudinal magnetic fields up to 105 kG. For fields above 25 kG, the mass loss and cross‐sectional area of the cylindrical blow‐off plasma varied as B−6/5. For these cases, only the 60‐nsec gain‐switched laser spike caused target damage; the 1.5‐μsec tail was absorbed by a ∼100‐eV partially confined plasma extending several cm from the target. The field dependence of the plasma cross section is consistent with an adiabatic expansion against the magnetic field.

Induced birefringence, or the electro-optic Kerr effect, has been used by a number of authors to study the steady-state distribution of space charge in a parallel-plate capacitor with nitrobenzene or chlorobenzene.1-9

Using the large aperture spectrometer of proposal 144 and the electron beam with the tagging system removed we propose to study deep inelastic electron scattering at incident electron energies between 50 and 150 GeV, for values of q{sup 2} between 1 and 20 Gev{sup 2}/c and {nu} between 10 and 130 GeV. The spectrometer will detect not only the scattered electron but also most of the secondary particles.

In NAL Proposal No.144, we described a three magnet system, consisting of a forward focussing spectrometer made up of two large aperture magnets, M1 and M2, and a solenoid magnet from the PPA to detect the recoil proton. This spectrometer will enable us to study seven experimental reactions at the same time with high precision.

An attempt was made to detect cosmic ray tracks using a pulsed TEA CO2 laser. Within 4 μsec of the passage of a cosmic ray through a pressurized cell, a laser beam of 4 J/cm2 energy density at 10.6 μ was fired. Pure argon and argon‐krypton mixtures were studied at pressures up to 12 atm. Spots of light were seen but no tracks. Laser damage to the cell windows was the limiting factor. An alternative detector using an initial high‐voltage pulse followed by a laser pulse is proposed.