Pulsed magnetron oscillators sometimes show an instability known as “twinning” in which the spectrum shows two, or more, closely spaced peaks. This phenomenon is undesirable and can lead to problems when it occurs in magnetrons used in radars. An experimental investigation of twinning is described from which conclusions are drawn about the design parameters that affect it. It has been shown tha...

This paper describes an evolving computational model of the perception and production of simple rhythmic patterns. The model consists of a network of oscillators of different resting frequencies which couple with input patterns and with each other. Oscillators whose frequencies match periodicities in the input tend to become activated. Metrical structure is represented explicitly in the network...

We study synchronization transitions in a system of two coupled self-sustained chaotic oscillators. We demonstrate that with the increase of coupling strength the system first undergoes the transition to phase synchronization. With a further increase of coupling, a new synchronous regime is observed, where the states of two oscillators are nearly identical, but one system lags in time to the ot...

In this work we present experimental and calculated two-dimensional electronic spectra for a 5,15-bisalkynyl porphyrin chromophore. The lowest energy electronic Qy transition couples mainly to a single 380 cm(-1) vibrational mode. The two-dimensional electronic spectra reveal diagonal and cross peaks which oscillate as a function of population time. We analyze both the amplitude and phase distr...

Optical properties of symmetry-forbidden π-π transitions in benzene are calculated with the time-dependent density functional theory (TDDFT), using an adiabatic LDA functional. Quantities calculated are the envelopes of the Franck-Condon factors of the vibrationally promoted transitions and the associated oscillator strengths. The strengths, which span three orders of magnitude, are reproduced ...

We show that for the strictly isospectral Hamiltonians, the corresponding coherent states are related by a unitary transformation. As an illustration, we discuss, the example of strictly isospectral one-dimensional harmonic oscillator Hamiltonians and the associated coherent states. PACS number(s) : 03.65.Fd, 02.30.+b Electronic Address : [email protected] Electronic Address : [email protected]...

We consider time-dependent Gaussian wave packet solutions of the Schrödinger equation (with arbitrary initial central position, x0, and momentum, p0, for an otherwise free-particle, but with an infinite wall at x = 0, so-called bouncing wave packets. We show how difference or mirror solutions of the form ψ(x, t)−ψ(−x, t) can, in this case, be normalized exactly, allowing for the evaluation of a...

Radiative transition parameters are tabulated for the ARu X Rg band system of the silver dimer Ag2 for bands involving vibrational levels up to v0 1⁄4 54 and v00 1⁄4 98, which amply covers the band transitions empirically studied in the seminal work of Kleman and Lindkvist [B. Kleman, S. Lindkvist, Arkiv för Fysik 9 (1955) 385–390]. The tabulated parameters include band-origin wavelengths and w...