Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun

The room temperature continuous wave (cw) very-high-frequency (VHF) gun is one of the candidates for the electron gun of the high-repetition-rate free-electron lasers (FELs). The VHF gun operates with a cathode gradient of ∼20  MV/m and an accelerating voltage of ∼750  kV. The gun dark current emiss...

Full description

Saved in:
Bibliographic Details
Main Authors: Xing-Heng Wang, Guan Shu, Hou-Jun Qian, Xu-Dong Li, Zi-Peng Liu, Zeng-Gong Jiang, Hao Meng, Cao-Cao Xing, Qin Zhou, Hai-Xiao Deng
Format: Article
Language:English
Published: American Physical Society 2025-04-01
Series:Physical Review Accelerators and Beams
Online Access:http://doi.org/10.1103/PhysRevAccelBeams.28.043401
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849704229045796864
author Xing-Heng Wang
Guan Shu
Hou-Jun Qian
Xu-Dong Li
Zi-Peng Liu
Zeng-Gong Jiang
Hao Meng
Cao-Cao Xing
Qin Zhou
Hai-Xiao Deng
author_facet Xing-Heng Wang
Guan Shu
Hou-Jun Qian
Xu-Dong Li
Zi-Peng Liu
Zeng-Gong Jiang
Hao Meng
Cao-Cao Xing
Qin Zhou
Hai-Xiao Deng
author_sort Xing-Heng Wang
collection DOAJ
description The room temperature continuous wave (cw) very-high-frequency (VHF) gun is one of the candidates for the electron gun of the high-repetition-rate free-electron lasers (FELs). The VHF gun operates with a cathode gradient of ∼20  MV/m and an accelerating voltage of ∼750  kV. The gun dark current emission leads to beam loss along the FEL machine, therefore, it is a critical parameter for the performance of the cw gun. In this paper, we present a systematic study of the dark current reduction of the VHF gun, including cathode region optimizations, dark current tracking simulations, and measurements. Over-inserted cathode plugs were tested in two VHF guns of different acceleration gap sizes, and both demonstrated significant dark current reduction ratios of more than two orders of magnitude.
format Article
id doaj-art-507b0ddb2a2e4c1691d1932ad1456592
institution DOAJ
issn 2469-9888
language English
publishDate 2025-04-01
publisher American Physical Society
record_format Article
series Physical Review Accelerators and Beams
spelling doaj-art-507b0ddb2a2e4c1691d1932ad14565922025-08-20T03:16:50ZengAmerican Physical SocietyPhysical Review Accelerators and Beams2469-98882025-04-0128404340110.1103/PhysRevAccelBeams.28.043401Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gunXing-Heng WangGuan ShuHou-Jun QianXu-Dong LiZi-Peng LiuZeng-Gong JiangHao MengCao-Cao XingQin ZhouHai-Xiao DengThe room temperature continuous wave (cw) very-high-frequency (VHF) gun is one of the candidates for the electron gun of the high-repetition-rate free-electron lasers (FELs). The VHF gun operates with a cathode gradient of ∼20  MV/m and an accelerating voltage of ∼750  kV. The gun dark current emission leads to beam loss along the FEL machine, therefore, it is a critical parameter for the performance of the cw gun. In this paper, we present a systematic study of the dark current reduction of the VHF gun, including cathode region optimizations, dark current tracking simulations, and measurements. Over-inserted cathode plugs were tested in two VHF guns of different acceleration gap sizes, and both demonstrated significant dark current reduction ratios of more than two orders of magnitude.http://doi.org/10.1103/PhysRevAccelBeams.28.043401
spellingShingle Xing-Heng Wang
Guan Shu
Hou-Jun Qian
Xu-Dong Li
Zi-Peng Liu
Zeng-Gong Jiang
Hao Meng
Cao-Cao Xing
Qin Zhou
Hai-Xiao Deng
Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
Physical Review Accelerators and Beams
title Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
title_full Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
title_fullStr Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
title_full_unstemmed Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
title_short Experimental demonstration of dark current mitigation by an over-inserted plug in a normal conducting very-high-frequency gun
title_sort experimental demonstration of dark current mitigation by an over inserted plug in a normal conducting very high frequency gun
url http://doi.org/10.1103/PhysRevAccelBeams.28.043401
work_keys_str_mv AT xinghengwang experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT guanshu experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT houjunqian experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT xudongli experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT zipengliu experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT zenggongjiang experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT haomeng experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT caocaoxing experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT qinzhou experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun
AT haixiaodeng experimentaldemonstrationofdarkcurrentmitigationbyanoverinsertedpluginanormalconductingveryhighfrequencygun