FEL2012 - List of Authors (Nagasawa, I.)

Paper	Title	Page
MOPD45	Present Status of Thermionic RF-Gun for Terahertz Source Project at Tohoku University	137
	F. Hinode, H. Hama, N.Y. Huang, S. Kashiwagi, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan X. Li TUB, Beijing, People's Republic of China
	Funding: This work is partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (S), Contract #20226003. A thermionic RF gun for an acceleratora-based terahertz source has been commissioned at Electron Light Science Centre, Tohoku University. The RF gun consisting of two independently-tunable cells (ITC RF gun) can be operated so as to optimize the phase space distribution of the extracted electrons for the further manipulation in an alpha magnet and a 3 m accelerating structure for the short pulse generation. Tracking simulations show that very short electron pulse less than 100 fs with a bunch charge of about 20 pC can be obtained by means of the velocity bunching in the accelerating structure. In the early result of the gun commissioning, it was shown that the back-bombardment (B-B) effect was rather serious for the beam quality in spite of the operation with the short pulse length and slow repetition rate. The simulation study for the B-B effect with the 2D heat transfer model turned out that low energy electrons coming back in the cathode cell have the significant contribution for the additional cathode heating rather than the higher energy electrons. We will show the recent results of beam commissioning of the ITC RF gun and the current status of t-ACTS project. H. Hama et al., New J. Phys. 8 (2006) 292, **X. Li et al., Proc. of FEL'11, (2011) THPA17

Paper

Title

Page

Present Status of Thermionic RF-Gun for Terahertz Source Project at Tohoku University

137

F. Hinode, H. Hama, N.Y. Huang, S. Kashiwagi, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
X. Li
TUB, Beijing, People's Republic of China

Funding: This work is partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (S), Contract #20226003.
A thermionic RF gun for an acceleratora-based terahertz source has been commissioned at Electron Light Science Centre, Tohoku University*. The RF gun consisting of two independently-tunable cells (ITC RF gun) can be operated so as to optimize the phase space distribution of the extracted electrons for the further manipulation in an alpha magnet and a 3 m accelerating structure for the short pulse generation. Tracking simulations show that very short electron pulse less than 100 fs with a bunch charge of about 20 pC can be obtained by means of the velocity bunching in the accelerating structure. In the early result of the gun commissioning, it was shown that the back-bombardment (B-B) effect was rather serious for the beam quality in spite of the operation with the short pulse length and slow repetition rate. The simulation study for the B-B effect with the 2D heat transfer model turned out that low energy electrons coming back in the cathode cell have the significant contribution for the additional cathode heating rather than the higher energy electrons**. We will show the recent results of beam commissioning of the ITC RF gun and the current status of t-ACTS project.
*H. Hama et al., New J. Phys. 8 (2006) 292,
**X. Li et al., Proc. of FEL'11, (2011) THPA17