Parity-conserving and -violating response functions are computed for the inclusive electroexcitation of the N∗(1440) (Roper) resonance in nuclear matter modeled as a relativistic Fermi gas. Using various empirical parameterizations and theoretical models of the N −N∗(1440) transition form factors, the sensitivity of the response functions to details of the structure of the Roper resonance is in...

Parity-conserving and -violating response functions are computed for the inclusive electroexcitation of the N∗(1440) (Roper) resonance in nuclear matter modeled as a relativistic Fermi gas. Using various empirical parameterizations and theoretical models of the N −N∗(1440) transition form factors, the sensitivity of the response functions to details of the structure of the Roper resonance is in...

We consider the maximum entropy extention of a partially specified autocovariance sequence of a periodically correlated process. The sequence may be specified on a non-contiguous set. We give a method which solves the problem completely—it gives the positive definite solution when it exists and reports that it does not exist otherwise. The method is numerically reliable even when the solution i...

In this paper we propose an architecture as a framework for decomposition and analysis of hybrid systems. We represent a computer system's behaviour in interaction with its physical environment using modular models and the combination of discrete and continuous modelling techniques. To this end, a modular extention of timed transition systems, Hybrid Transition Systems, are presented. For this ...

We employ a continuum approach to the three valence-quark bound-state problem in relativistic quantum field theory to predict a range of properties of the proton's radial excitation and thereby unify them with those of numerous other hadrons. Our analysis indicates that the nucleon's first radial excitation is the Roper resonance. It consists of a core of three dressed quarks, which expresses i...

To the Editorial Committee of the BRITISH JOURNAL OF OPHTHALMOLOGY SiRs-In my recent article on the use of oxyphenonium as an atropine substitute (Roper-Hall, 1957) I stated that a previous atropine substitute, Lachesine, had been withdrawn from production. This was true at the date when the article was written in November, 1956, but I have recently learned that Lachesine is now being manufactu...

A description of the Roper using the chiral chromodielectric model is presented and the transverse A1/2 and the scalar S1/2 helicity amplitudes for the electromagnetic Nucleon–Roper transition are obtained for small and moderate Q. The sign of the amplitudes is correct but the model predictions underestimate the data at the photon point. Our results do not indicate a change of sign in any ampli...

This article presents a case of infective endocarditis secondary to ventricular septal defect with an extention of a process to mitral and aortic valves.