The design of a crossed molecular beam ''supermachine'' for neutral-- neutral collisions is discussed. The universal electron bombardment ionizer, mass filter, and ion detection system of the detector, the supersonic nozzle sources, the differential pumping arrangement for the sources and detector, the time-of-flight detection of scattered products, and the overall configuration of the apparatus are described. The elastic scattering of two systems, CH$sub 4$ + Ar and NH$sub 3$ + Ar, has been measured using the supermachine with two supersonic nozzle sources. The rainbow structure and the interference oscillations are seen in each system. The best fit to the data was found using a Morse--Spline--Van der Waals (MSV) potential. The three potential parameters epsilon, r/sub m/, and $beta$ were found to be 2.20(+-0.04) x 10$sup -14$ ergs, 3.82(+-0.04)A, and 7.05 +- 0.20 for CH$sub 4$ + Ar, and 2.21(+-0.04) x 10$sup - 14$ ergs 3.93 (+-0.05)A, and 8.45 +- 0.30 for NH$sub 3$ + Ar. A new phenomenon in crossed molecular beams of condensation of a molecule on a cluster to form a complex was observed. A bromine molecule condensed on clusters of chlorine (Cl$sub 2$)/sub chi/ and ammonia (NH$sub 3$)/sub chi/. The value of chi for measurements in these …

A theoretical analysis is made of the longitudinal stability of intense beams of charged particles in high energy storage rings. The effect of externally applied radiofrequency fields, i.e., synchrotron oscillations, is included. For electron and positron beams, the damping and quantum excitation due to particle radiation are also included. A criterion for the stability of small longitudinal plasma oscillations is derived and used to obtain the stable size of intense stored beams of electrons and positrons. (auth)

The nature of defects resulting from the implantation of phosphorous ions into doped silicon and a model of how they form are reported. This involved an electron microscope study of the crystallographic defects (in the 300A size range in concentration of 10$sup 15$/cm$sup 3$) that form upon annealing. Images formed by these crystallographic defects are complex and that nonconventional imaging techniques are required for their characterization. The images of these small defects (about 300A) are sensitive to various parameters, such as foil thickness, their position in the foil, and diffracting conditions. The defects were found to be mostly interstitial hexagonal Frank loops lying on the four [111] planes and a few perfect interstitial loops; these loops occurred in concentrations of about 10$sup 16$/cm$sup 3$. In addition, ''rod like'' linear defects that are shown to be interstitial are also found in concentrations of 10$sup 13$/cm$sup 3$. It was found that the linear defects require boron for their formation. A model is proposed to account for the interstitial defects. The number of point defects that make up the defects is of the same order as the number of implanted ions. The model predicts that only interstitial loops ought to be observed in …

An experimental measurement of the spectrum of the submillimeter cosmic background radiation is described. The experiment consists of measuring the night sky emission at an altitude of 39 km, correcting for the atmospheric molecular line emission, and placing limits on the contamination from sources of continuum radiation such as the apparatus itself and the earth. The observations were made on 24 July 1974 using a fully calibrated liquid-helium-cooled balloon- borne spectrophotometer. Important features of the apparatus include a cooled antenna, a polarizing interferometer, and a germanium bolometric detector. The characterization of the spectrophotometer includes the large angle response and emission of the antenna. The calibration of the instrument and corrections to the observed sky spectrum are based on measurements made during the flight. A simple model of the molecular line emission is used to determine the atmospheric contribution. The resulting spectrum covers the frequency range from 4 to 17 cm$sup -1$ and establishes that the cosmic background radiation follows the high frequency quantum cutoff for a 3K blackbody. A blackbody temperature of 2.99/sub -.$sub 14$/$sup +$.$sup 07$/K is deduced from our data. The present status of the cosmic background observations, which span more than three decades in frequency, is analyzed …

The results of a measurement of the $pi$$sup -$p $Yields$ $pi$$sup 0$n and $pi$$sup -$p $Yields$ eta n differential cross sections at six pion beam momenta from 20 to 200 GeV/c are presented. The data for these cross sections were collected at the Fermi National Accelerator Laboratory in Batavia, Illinois. A 73.5 x 73.5 cm lead--scintillator hodoscope was used to detect the two photons from the decay of the $pi$$sup 0$ and the eta; all other reactions were eliminated by detection of their charged particles and additional photons in an array of veto counters. The zero-degree charge exchange cross sections determined from these measurements are shown to be consistent with the measured $pi$$sup +$p and $pi$$sup -$p total cross section differences. Effective Regge trajectories for the rho and the A$sub 2$ also extracted from the data. 34 figures, 9 tables. (auth)

Total cross sections have been measured for protons, deuterons, alphas, and $sup 12$C on hydrogen, deuterium, helium, and carbon targets at 1.55 and 2.89 GeV/c/nucleon using the ''good geometry'' transmission method. In addition, the inelastic cross sections and elastic slope parameters were measured for reactions initiated by deuterons, alphas, and $sup 12$C. The factorization relation sigma/ sub T/(AA) = sigma/sub T/(AB)$sup 2$/sigma/sub T/(BB) is violated for some of these reactions. The results generally agree with Glauber theory predictions except in their detailed energy behavior. It is found that sigma/sub T/ approximately equal to 144 (A/sub T//sup $sup 1$/$sub 3$/ + A/sub P//sup $sup 1$/ $sub 3$/ - 1.48)$sup 2$ and sigma/sub IN/ approximately equal to 78 (A/sub T//sup $sup 1$/$sub 3$/ + A/sub P//sup $sup 1$/$sub 3$/ - 1.25)$sup 2$, where A/sub T/(A/ sub P/) is the atomic mass number of the target (projectile) and the cross sections are given in mb. (auth)