527 GHz gyrotron for DNP-NMR spectroscopy

Author

Jawla, Sudheer ; Shapiro, Michael ; Guss, William ; Temkin, Richard

Author_Institution

Plasma Sci. & Fusion Center, Massachusetts Inst. of Technol., Cambridge, MA, USA

fYear

2012

fDate

24-26 April 2012

Firstpage

205

Lastpage

206

Abstract

We describe the design of a 20W, continuous wave 527 GHz gyrotron for Dynamic Nuclear Polarization (DNP) enhanced solid state Nuclear Magnetic Resonance (NMR) spectroscopy on an 800 MHz spectrometer. A 9.8 T helium-free superconducting magnet with a warm bore diameter of 76mm is planned for the gyrotron operation. The gyrotron resonator cavity is designed to operate in the TE_11,3,p mode at 527 GHz which is the second harmonic (ω=2ω_c) of the electron cyclotron frequency. The design is based on a diode electron gun (V_k=15 kV, I_b=190 mA) and lateral output with an internal Vlasov-type mode converter. Frequency tunability of Δf/f ≈ 0.25% is being studied around the nominal frequency of 527 GHz, with a goal of constant output power of more than 20W.

Keywords

NMR spectroscopy; cavity resonators; convertors; cyclotrons; dynamic nuclear polarisation; electron guns; gyrotrons; submillimetre wave tubes; superconducting magnets; DNP-NMR spectroscopy; TE_11,3,p mode; continuous wave gyrotron; current 190 mA; diode electron gun; dynamic nuclear polarization enhanced solid state nuclear magnetic resonance spectroscopy; electron cyclotron frequency; frequency 527 GHz; frequency 800 MHz; gyrotron resonator cavity; helium-free superconducting magnet; internal Vlasov-type mode converter; magnetic flux density 9.8 T; power 20 W; size 76 mm; spectrometer; voltage 15 kV; Cavity resonators; Cyclotrons; Gyrotrons; Harmonic analysis; Magnetic fields; Nuclear magnetic resonance; Polarization; Dynamic Nuclear Polarization; Electron cyclotron frequency; Gyrotrons; Mode converter;

fLanguage

English

Publisher

ieee

Conference_Titel

Vacuum Electron Sources Conference (IVESC), 2012 IEEE Ninth International

Conference_Location

Monterey, CA

Print_ISBN

978-1-4673-0368-2

Type

conf

DOI

10.1109/IVESC.2012.6264178

Filename

6264178