rf breakdown tests of mm-wave metallic accelerating structures

Dal Forno, Massimo; Dolgashev, Valery; Bowden, Gordon; Clarke, Christine; Hogan, Mark; McCormick, Doug; Novokhatski, Alexander; Spataro, Bruno; Weathersby, Stephen; Tantawi, Sami G.

doi:10.1103/PhysRevAccelBeams.19.011301

Title: rf breakdown tests of mm-wave metallic accelerating structures

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Abstract

In this study, we explore the physics and frequency-scaling of vacuum rf breakdowns at sub-THz frequencies. We present the experimental results of rf tests performed in metallic mm-wave accelerating structures. These experiments were carried out at the facility for advanced accelerator experimental tests (FACET) at the SLAC National Accelerator Laboratory. The rf fields were excited by the FACET ultrarelativistic electron beam. We compared the performances of metal structures made with copper and stainless steel. The rf frequency of the fundamental accelerating mode, propagating in the structures at the speed of light, varies from 115 to 140 GHz. The traveling wave structures are 0.1 m long and composed of 125 coupled cavities each. We determined the peak electric field and pulse length where the structures were not damaged by rf breakdowns. We calculated the electric and magnetic field correlated with the rf breakdowns using the FACET bunch parameters. The wakefields were calculated by a frequency domain method using periodic eigensolutions. Such a method takes into account wall losses and is applicable to a large variety of geometries. The maximum achieved accelerating gradient is 0.3 GV/m with a peak surface electric field of 1.5 GV/m and a pulse length of about 2.4more » ns.« less

Authors:: Dal Forno, Massimo; Dolgashev, Valery; Bowden, Gordon; Clarke, Christine; Hogan, Mark; McCormick, Doug; Novokhatski, Alexander; Spataro, Bruno; Weathersby, Stephen; Tantawi, Sami G.

Publication Date:: Wed Jan 06 00:00:00 EST 2016

Research Org.:: SLAC National Accelerator Lab., Menlo Park, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1235793

Alternate Identifier(s):: OSTI ID: 1242260; OSTI ID: 1242464; OSTI ID: 1443583

Report Number(s):: SLAC-PUB-16494
Journal ID: ISSN 2469-9888; PRABFM; 011301

Grant/Contract Number:: AC02-76SF00515

Resource Type:: Published Article

Journal Name:: Physical Review Accelerators and Beams

Additional Journal Information:: Journal Name: Physical Review Accelerators and Beams Journal Volume: 19 Journal Issue: 1; Journal ID: ISSN 2469-9888

Publisher:: American Physical Society

Country of Publication:: United States

Language:: English

Subject:: 43 PARTICLE ACCELERATORS; advanced accelerator test facilities; plasma acceleration; new acceleration techniques; radio frequency calculations

Citation Formats


                    Dal Forno, Massimo, Dolgashev, Valery, Bowden, Gordon, Clarke, Christine, Hogan, Mark, McCormick, Doug, Novokhatski, Alexander, Spataro, Bruno, Weathersby, Stephen, and Tantawi, Sami G. rf breakdown tests of mm-wave metallic accelerating structures.  United States: N. p., 2016. 
Web.  doi:10.1103/PhysRevAccelBeams.19.011301.

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                    Dal Forno, Massimo, Dolgashev, Valery, Bowden, Gordon, Clarke, Christine, Hogan, Mark, McCormick, Doug, Novokhatski, Alexander, Spataro, Bruno, Weathersby, Stephen, & Tantawi, Sami G. rf breakdown tests of mm-wave metallic accelerating structures.  United States.  https://doi.org/10.1103/PhysRevAccelBeams.19.011301

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                    Dal Forno, Massimo, Dolgashev, Valery, Bowden, Gordon, Clarke, Christine, Hogan, Mark, McCormick, Doug, Novokhatski, Alexander, Spataro, Bruno, Weathersby, Stephen, and Tantawi, Sami G. Wed .  
"rf breakdown tests of mm-wave metallic accelerating structures".  United States.  https://doi.org/10.1103/PhysRevAccelBeams.19.011301.

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@article{osti_1235793,

  title        = {rf breakdown tests of mm-wave metallic accelerating structures},

  author       = {Dal Forno, Massimo and Dolgashev, Valery and Bowden, Gordon and Clarke, Christine and Hogan, Mark and McCormick, Doug and Novokhatski, Alexander and Spataro, Bruno and Weathersby, Stephen and Tantawi, Sami G.},

  abstractNote = {In this study, we explore the physics and frequency-scaling of vacuum rf breakdowns at sub-THz frequencies. We present the experimental results of rf tests performed in metallic mm-wave accelerating structures. These experiments were carried out at the facility for advanced accelerator experimental tests (FACET) at the SLAC National Accelerator Laboratory. The rf fields were excited by the FACET ultrarelativistic electron beam. We compared the performances of metal structures made with copper and stainless steel. The rf frequency of the fundamental accelerating mode, propagating in the structures at the speed of light, varies from 115 to 140 GHz. The traveling wave structures are 0.1 m long and composed of 125 coupled cavities each. We determined the peak electric field and pulse length where the structures were not damaged by rf breakdowns. We calculated the electric and magnetic field correlated with the rf breakdowns using the FACET bunch parameters. The wakefields were calculated by a frequency domain method using periodic eigensolutions. Such a method takes into account wall losses and is applicable to a large variety of geometries. The maximum achieved accelerating gradient is 0.3 GV/m with a peak surface electric field of 1.5 GV/m and a pulse length of about 2.4 ns.},

  doi          = {10.1103/PhysRevAccelBeams.19.011301},

  journal      = {Physical Review Accelerators and Beams},

  number       = 1,

  volume       = 19,

  place        = {United States},

  year         = {Wed Jan 06 00:00:00 EST 2016},

  month        = {Wed Jan 06 00:00:00 EST 2016}

}

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