PAC2013 - List of Authors (Shin, Y.-M.)

Paper	Title	Page
MOPAC17	RF-Components Embedded with Photonic-Band-Gap (PBG) and Fishnet-Metamaterial Structures for High Frequency Accelerator Application	102
	Y.-M. Shin Fermilab, Batavia, USA D. Boyden, S. Robak Northern Illinois University, DeKalb, Illinois, USA
	For development of high gradient RF-accelerators, RF waveguides and cavities have been designed with Photonic Band Gap (PBG) and fishnet-metamaterial structures. The designed structures are comprised of a periodically corrugated channel sandwiched between two photonic crystal slabs with alternating high to low dielectric constants and a multi-cell cavity-resonator designed with fishnet-metamaterial apertures. The structural designs are intended to only allow an operating-mode or -band within a narrow frequency range to propagate. The simulation analysis shows that trapped non-PBG modes are effectively suppressed down to ~ - 14.3 dB/cm, while PBG modes propagated with ~ 2 dB of insertion loss, corresponding to ~1.14 dB/cm attenuation. The preliminary modeling analysis on the fishnet-embedded cavity shows noticeable improvement of Q-factor and field gradient of the operating mode (TM010) compared to those of PBG-cavities. It is planned to test the fabricated Ka-band PBG-waveguide and S-band fishnet cavity structures with a microwave test bench/8510C Network Analyzer and 5.5 MW S-band klystron respectively.

TUPSM11	Development of a Compact Photo-injector with RF-Focusing Lens for Short Pulse Electron Source Application	655
	Y.-M. Shin Fermilab, Batavia, USA D.W. Eaton Scandinova Systems AB, Uppsala, Sweden A.F. Grabenhofer Northern Illinois University, DeKalb, Illinois, USA
	For development of compact ultrafast electron source system, we have been designing a short-pulse RF-gun with RF focusing structure with comprehensive modeling analysis processes. EM design of a 2.5 cell resonant cavity with input coupler, acceleration dynamics of photo-emitted electron bunch, EM design of RF-lens with input coupler, and phase-space analysis of focused electron bunch are systematically examined with multi-physics simulators. All the features of the 2.856 GHz cavity geometry were precisely engineered for acceleration energies ranging from 100 keV to 500 keV (safety limited) to be powered by our 5.5 MW S-band klystron. The klystron (Thales TH2163) and modulator system (ScandiNova K1 turnkey system) were successfully installed and tested. Performance tests of the klystron system show peak output power >5 MW, as per operation specifications.

TUPSM12	High Power Test of a 3.9 GHz 5-Cell Deflecting-Mode Cavity in a Cryogenic Operation	658
	Y.-M. Shin, M.D. Church Fermilab, Batavia, USA
	A 3.9 GHz deflecting mode (pi, TM110) cavity has been long used for six-dimensional phase-space beam manipulation tests * * ** *** at the A0 Photo-Injector Lab (16 MeV) in Fermilab and their extended applications with vacuum cryomodules are currently planned at the Advanced Superconducting Test Accelerator (ASTA) user facility (> 50 MeV). Despite the successful test results, the cavity, however, demonstrated limited RF performance during liquid nitrogen (LN2) ambient operation that was inferior to theoretical prediction. We have been performing full analysis of the designed cavity by analytic calculation and comprehensive system simulation analysis to solve complex thermodynamics and mechanical stresses. The re-assembled cryomodule is currently under the test with a 50 kW klystron at the Fermilab A0 beamline, which will benchmark the modeling analysis. The test result will be used to design vacuum cryomodules for the 3.9 GHz deflecting mode cavity that will be employed at the ASTA facility for beam diagnostics and phase-space control. * D. A. Edwards, LINAC 2002 Y.-E Sun, PRTAB 2004 * P. Piot, PRSTAB2006 ** J. Ruand et al., PRL 2011 *** Y.-E. Sun, et al., PRL 2010

MOPAC18	Feasibility Study of Channeling Acceleration Experiment at the Fermilab ASTA Facility	105
	Y.-M. Shin, T. Xu Northern Illinois University, Dekalb, USA V.D. Shiltsev, D.A. Still Fermilab, Batavia, USA
	The density of charge carriers in solids, 4 ~ 5 orders of magnitude higher than those in gaseous plasma, can in principle create an accelerating field gradient up to 10 – 31.6 TeV/m. This extremely high acceleration gradient can offer various opportunities in accelerator community for future HEP collider in Energy Frontier. It was suggested that particles are accelerated along major crystallographic directions. The ions and photons are readily confined in the atomic tunnel of an angstrom-scale aperture, so called the channeling effect, which can accelerate heavy particles like muons from an x-ray laser or electrons from a drive beam. Carbon-based nanostructures have great potential with a wide range of flexibility and superior physical strength, which can be applied to channeling acceleration. The ASTA in Fermilab is currently designed with 1 ps electron bunch with 1 ms duration and 5 Hz PRR at 50 – 300 MeV, which is properly fit for the channeling acceleration test. This paper will present current activity on crystal accelerator research, including acceleration concepts with crystals and nanotubes, and discuss feasible experiments with the ASTA and beyond.

Paper

Title

Page

RF-Components Embedded with Photonic-Band-Gap (PBG) and Fishnet-Metamaterial Structures for High Frequency Accelerator Application

102

Y.-M. Shin
Fermilab, Batavia, USA
D. Boyden, S. Robak
Northern Illinois University, DeKalb, Illinois, USA

For development of high gradient RF-accelerators, RF waveguides and cavities have been designed with Photonic Band Gap (PBG) and fishnet-metamaterial structures. The designed structures are comprised of a periodically corrugated channel sandwiched between two photonic crystal slabs with alternating high to low dielectric constants and a multi-cell cavity-resonator designed with fishnet-metamaterial apertures. The structural designs are intended to only allow an operating-mode or -band within a narrow frequency range to propagate. The simulation analysis shows that trapped non-PBG modes are effectively suppressed down to ~ - 14.3 dB/cm, while PBG modes propagated with ~ 2 dB of insertion loss, corresponding to ~1.14 dB/cm attenuation. The preliminary modeling analysis on the fishnet-embedded cavity shows noticeable improvement of Q-factor and field gradient of the operating mode (TM010) compared to those of PBG-cavities. It is planned to test the fabricated Ka-band PBG-waveguide and S-band fishnet cavity structures with a microwave test bench/8510C Network Analyzer and 5.5 MW S-band klystron respectively.

TUPSM11

Development of a Compact Photo-injector with RF-Focusing Lens for Short Pulse Electron Source Application

655

Y.-M. Shin
Fermilab, Batavia, USA
D.W. Eaton
Scandinova Systems AB, Uppsala, Sweden
A.F. Grabenhofer
Northern Illinois University, DeKalb, Illinois, USA

For development of compact ultrafast electron source system, we have been designing a short-pulse RF-gun with RF focusing structure with comprehensive modeling analysis processes. EM design of a 2.5 cell resonant cavity with input coupler, acceleration dynamics of photo-emitted electron bunch, EM design of RF-lens with input coupler, and phase-space analysis of focused electron bunch are systematically examined with multi-physics simulators. All the features of the 2.856 GHz cavity geometry were precisely engineered for acceleration energies ranging from 100 keV to 500 keV (safety limited) to be powered by our 5.5 MW S-band klystron. The klystron (Thales TH2163) and modulator system (ScandiNova K1 turnkey system) were successfully installed and tested. Performance tests of the klystron system show peak output power >5 MW, as per operation specifications.

TUPSM12

High Power Test of a 3.9 GHz 5-Cell Deflecting-Mode Cavity in a Cryogenic Operation

658

Y.-M. Shin, M.D. Church
Fermilab, Batavia, USA

A 3.9 GHz deflecting mode (pi, TM110) cavity has been long used for six-dimensional phase-space beam manipulation tests * ** *** **** ***** at the A0 Photo-Injector Lab (16 MeV) in Fermilab and their extended applications with vacuum cryomodules are currently planned at the Advanced Superconducting Test Accelerator (ASTA) user facility (> 50 MeV). Despite the successful test results, the cavity, however, demonstrated limited RF performance during liquid nitrogen (LN2) ambient operation that was inferior to theoretical prediction. We have been performing full analysis of the designed cavity by analytic calculation and comprehensive system simulation analysis to solve complex thermodynamics and mechanical stresses. The re-assembled cryomodule is currently under the test with a 50 kW klystron at the Fermilab A0 beamline, which will benchmark the modeling analysis. The test result will be used to design vacuum cryomodules for the 3.9 GHz deflecting mode cavity that will be employed at the ASTA facility for beam diagnostics and phase-space control.
* D. A. Edwards, LINAC 2002
** Y.-E Sun, PRTAB 2004
*** P. Piot, PRSTAB2006
**** J. Ruand et al., PRL 2011
***** Y.-E. Sun, et al., PRL 2010

MOPAC18

Feasibility Study of Channeling Acceleration Experiment at the Fermilab ASTA Facility

105

Y.-M. Shin, T. Xu
Northern Illinois University, Dekalb, USA
V.D. Shiltsev, D.A. Still
Fermilab, Batavia, USA

The density of charge carriers in solids, 4 ~ 5 orders of magnitude higher than those in gaseous plasma, can in principle create an accelerating field gradient up to 10 – 31.6 TeV/m. This extremely high acceleration gradient can offer various opportunities in accelerator community for future HEP collider in Energy Frontier. It was suggested that particles are accelerated along major crystallographic directions. The ions and photons are readily confined in the atomic tunnel of an angstrom-scale aperture, so called the channeling effect, which can accelerate heavy particles like muons from an x-ray laser or electrons from a drive beam. Carbon-based nanostructures have great potential with a wide range of flexibility and superior physical strength, which can be applied to channeling acceleration. The ASTA in Fermilab is currently designed with 1 ps electron bunch with 1 ms duration and 5 Hz PRR at 50 – 300 MeV, which is properly fit for the channeling acceleration test. This paper will present current activity on crystal accelerator research, including acceleration concepts with crystals and nanotubes, and discuss feasible experiments with the ASTA and beyond.