Research on the secondary electron yield of tizrv-pd thin film coatings

In particle accelerators, the build-up of electron cloud may have important influence on beam quality. Especially for the positron and proton accelerators, massive electrons lead to electron cloud, which affects the stability, energy, emittance and beam life adversely. A secondary electron emission (SEE) measurement system has been designed and used to study the SEE of palladium (Pd), TiZrV and TiZrV-Pd with an independently adjustable energy from 50 eV to 5 keV. Here, we obtained the characteristics of the SEE from Pd, TiZrV and TiZrV-Pd film coatings with different thickness under ultrahigh-vacuum (UHV) conditions. Moreover, the maximum secondary electron yield (SEY), {\delta}max, of the Pd, TiZrV and TiZrV-Pd film coatings under different primary electron doses were obtained, respectively. Finally, the variation of the secondary electron yield with the incident electron energy will be discussed for Pd, TiZrV and TiZrV-Pd thin film coatings. Low SEY is a new advantage of TiZrV-Pd films, besides high H2 absorption ability and prolonging the lifetime of TiZrV film, which will be of great value in the design of beam screen for Super Proton-Proton Collider (SPPC).