February 14, 2014

Presentation of a new single slow traveling wave structure

A new accelerating structure with single slowly propagating TM10 wave is presented in the article of Dr. Mikhael Ivanyan published in February 2014 issue of Physical Review Special Topics.

The study of the new type of the slowly traveling wave structures is driven by the development of both novel coherent radiation sources and advanced acceleration concepts. The disc- or dielectric loaded structures are the most known slowly traveling wave structures that are characterized by the infinite number of excited modes.

The structure of a single slow traveling wave is of special interest since the relativistic charge will excite the synchronous mode only. The radiated energy is then effectively stored in a single mode and for short bunch length the structure will serve as a source for a coherent monochromatic radiation.

The new structure is composed of a metallic tube with an internally coated low conductive thin layer. It is shown that the impedance of the internally coated metallic tube has a narrow-band single resonance at a high frequency. The analytical presentation of the narrow band impedance, the wake function and the frequency of the synchronous mode are obtained. The main results of the article are verified by the exact numerical simulations.

The experimental study of the new single mode structure is foreseen at the AREAL test facility. This study will aim to verify the obtained results, develop new single mode accelerating structures, new monochromatic radiation sources in THz range and ultra-short bunch length measurements tools.