Low-noise, high-speed detector development for optical turbulence fluctuation measurements for NSTX


Schoenbeck N. L. , Ellington S. D. , Fonck R. J. , Jaehnig K., McKee G. R. , Smith D., ...Daha Fazla

REVIEW OF SCIENTIFIC INSTRUMENTS, cilt.81, sa.10, 2010 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 81 Konu: 10
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1063/1.3483196
  • Dergi Adı: REVIEW OF SCIENTIFIC INSTRUMENTS

Özet

A new beam emission spectroscopy (BES) diagnostic is under development. Photon-noise limited measurements of neutral beam emissions are achieved using photoconductive photodiodes with a novel frequency-compensated broadband preamplifier. The new BES system includes a next-generation preamplifier and upgraded optical coupling system. Notable features of the design are surface-mount components, minimized stray capacitance, a wide angular acceptance photodiode, a differential output line driver, reduced input capacitance, doubling of the frequency range, net reduced electronic noise, and elimination of the need for a cryogenic cooling system. The irreducible photon noise dominates the noise up to 800 kHz for a typical input power of 60 nW. This new assembly is being integrated into an upgraded multichannel optical detector assembly for a new BES system on the NSTX experiment. (C) 2010 American Institute of Physics. [doi:10.1063/1.3483196]