Magnetic wire stripping and connection method evaluation Final report, 15 Jun. - 11 Dec. 1965

Magnetic wire stripping and joining methods evaluatio

Design and development of a 5 kV isolated solid state switch

A unique microcircuit intended for use as a shorting switch for large extraterrestrial solar cell arrays is described. The packaging design for the 5 kV isolated hybrid switch is different from most hybrid microcircuits in that it utilizes a compartmentalized plastic case (a portion of which is encapsulated), is not hermetic, and is designed for high voltage operation

Baryon Current Matrix Elements in a Light-Front Framework

Current matrix elements and observables for electro- and photo-excitation of baryons from the nucleon are studied in a light-front framework. Relativistic effects are estimated by comparison to a nonrelativistic model, where we use simple basis states to represent the baryon wavefunctions. Sizeable relativistic effects are found for certain transitions, for example, to radial excitations such as that conventionally used to describe to the Roper resonance. A systematic study shows that the violation of rotational covariance of the baryon transition matrix elements stemming from the use of one-body currents is generally small.Comment: 32 pages, LaTeX, 10 postscript figures, uses epsf.sty; figures uuencoded with uufiles (or available by request in .ps or hardcopy form

Q2Q^2 Independence of QF2/F1QF_2/F_1, Poincare Invariance and the Non-Conservation of Helicity

A relativistic constituent quark model is found to reproduce the recent data regarding the ratio of proton form factors, $F_2(Q^2)/F_1(Q^2)$. We show that imposing Poincare invariance leads to substantial violation of the helicity conservation rule, as well as an analytic result that the ratio $F_2(Q^2)/F_1(Q^2)\sim 1/Q$ for intermediate values of $Q^2$.Comment: 13 pages, 7 figures, to be submitted to Phys. Rev. C typos corrected, references added, 1 new figure to show very high Q^2 behavio

Deep inelastic scattering and final state interaction in an exactly solvable relativistic model

In the theory of deep inelastic scattering (DIS) the final state interaction (FSI) between the struck quark and the remnants of the target is usually assumed to be negligible in the Bjorken limit. This assumption, still awaiting a full validation within nonperturbative QCD, is investigated in a model composed by two relativistic particles, interacting via a relativistic harmonic oscillator potential, within light-cone hamiltonian dynamics. An electromagnetic current operator whose matrix elements behave properly under Poincar\'e transformations is adopted. It is shown that: i) the parton model is recovered, once the standard parton model assumptions are adopted; and ii) when relativistic, interacting eigenfunctions are exactly taken into account for both the initial and final states, the values of the structure functions, averaged over small, but finite intervals of the Bjorken variable $x$, coincide with the results of the parton model in the Bjorken limit.Comment: 26 pages, to appear in Phys. Rev. C (May 1998

Poincare Invariant Algebra From Instant to Light-Front Quantization

We present the Poincare algebra interpolating between instant and light-front time quantizations. The angular momentum operators satisfying SU(2) algebra are constructed in an arbitrary interpolation angle and shown to be identical to the ordinary angular momentum and Leutwyler-Stern angular momentum in the instant and light-front quantization limits, respectively. The exchange of the dynamical role between the transverse angular mometum and the boost operators is manifest in our newly constructed algebra.Comment: 21 pages, 3 figures, 1 tabl

The Role of Color Neutrality in Nuclear Physics--Modifications of Nucleonic Wave Functions

The influence of the nuclear medium upon the internal structure of a composite nucleon is examined. The interaction with the medium is assumed to depend on the relative distances between the quarks in the nucleon consistent with the notion of color neutrality, and to be proportional to the nucleon density. In the resulting description the nucleon in matter is a superposition of the ground state (free nucleon) and radial excitations. The effects of the nuclear medium on the electromagnetic and weak nucleon form factors, and the nucleon structure function are computed using a light-front constituent quark model. Further experimental consequences are examined by considering the electromagnetic nuclear response functions. The effects of color neutrality supply small but significant corrections to predictions of observables.Comment: 37 pages, postscript figures available on request to [email protected]

Determination of the effects of a thermal sterilization process on the mechanical and electrical properties of soldered and welded joints Final report

Thermal sterilization effects on mechanical and electrical properties of soldered and welded joint