IPAC2013 - List of Authors (Uchida, K.U.)

Paper	Title	Page
MOPFI012	Measurement of Adsorption Rates of Residual Gases for NEA-GaAs Surface	306
	M. Kuriki, H. Iijima, K. Miyoshi, K.U. Uchida HU/AdSM, Higashi-Hiroshima, Japan
	A GaAs photocathode activated the surface to negative-electron-affinity (NEA) is an important device for high-average-current electron accelerators such as a next-generation light source based on an energy recovery linac. The NEA surface is normally formed by a yo-yo technique in which cesium and oxygen are applied onto the surface alternately. Although the initial quantum efficiency is relatively larger than that of another cathode, the lifetime is shorter. The degradation with time elapsing even if the electron beam is not extracted is mainly caused by adsorption of residual gases in a vacuum chamber. We have evaluated the adsorption rates of various gases for the NEA surface by measuring the dark lifetime in sample gases such as hydrogen, carbon oxide and carbon dioxide.

Paper

Title

Page

Measurement of Adsorption Rates of Residual Gases for NEA-GaAs Surface

306

M. Kuriki, H. Iijima, K. Miyoshi, K.U. Uchida
HU/AdSM, Higashi-Hiroshima, Japan

A GaAs photocathode activated the surface to negative-electron-affinity (NEA) is an important device for high-average-current electron accelerators such as a next-generation light source based on an energy recovery linac. The NEA surface is normally formed by a yo-yo technique in which cesium and oxygen are applied onto the surface alternately. Although the initial quantum efficiency is relatively larger than that of another cathode, the lifetime is shorter. The degradation with time elapsing even if the electron beam is not extracted is mainly caused by adsorption of residual gases in a vacuum chamber. We have evaluated the adsorption rates of various gases for the NEA surface by measuring the dark lifetime in sample gases such as hydrogen, carbon oxide and carbon dioxide.