Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 57 (1986), S. 1997-1997 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The tokamak fusion test reactor (TFTR) Michelson interferometer, which is used as an electron-temperature diagnostic, has a spectral range of 75–540 GHz. This range is adequate for measuring at least the first three cyclotron harmonics, and it spans both optically thick and thin portions of the electron cyclotron emission (ECE) spectrum. During the most recent opening of the TFTR vacuum vessel, a concave, carbon reflector was installed on the back wall of the vessel, opposite the light-collecting optic of the Michelson system. The reflector is designed to prevent the observation of optically thin ECE that originates from a location that is outside the field of view of the light collecting optic. If this is achieved, it should be possible to derive the electron-density profile from measurements of either the extraordinary mode third harmonic or the ordinary mode second harmonic. An analysis of ECE spectra that have been measured before and after installation of the reflector will be presented. This work was supported by U.S. DOE Contract No. DE-AC02-76-CHO-3073.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 57 (1986), S. 1999-1999 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Plasmas have been formed in the tokamak fusion test reactor (TFTR) which separate completely from the limiter and are called detached plasmas. The physical evidence for the separation from the limiter is that all the ohmic input power is radiated away at the plasma boundary which can be 10→30 cm inside the limiter. The 10-chord multichannel MIRI interferometer system has been used to diagnose this region and follows the formation of the detached state through a MARFE. MIRI indicates that a plasma ∼0.5→1×1013 cm−3 occurs in the region between the luminous boundary and the limiter. This work was supported by U.S. DOE Contract No. DE-AC02-76-CHO-3073.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 56 (1985), S. 925-927 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: In July 1984, a Fourier transform spectrometer employing a fast-scanning Michelson interferometer began operating on TFTR. This diagnostic system can measure the electron cyclotron emission spectrum 72 times per s with a time resolution of 11 ms and a spectral resolution of 3.6 GHz. The initial operating spectral range is 75–540 GHz, which is adequate for measuring the first three cyclotron harmonics at present TFTR magnetic field levels. The range can be extended easily to 75–1080 GHz in order to accommodate increases in toroidal magnetic field or to study superthermal ECE. The measured spectra are absolutely calibrated using a liquid nitrogen cooled blackbody reference source. The second harmonic feature of each spectrum is used to calculate the absolute electron temperature profile.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the past four years, a Fourier transform spectrometer diagnostic system, employing a fast-scanning polarizing Michelson interferometer (FMI), has been operating on the TFTR tokamak at the Princeton Plasma Physics Laboratory. It is used to measure the electron cyclotron emission (ECE) spectrum over the range 2.5–18 cm−1 (75–540 GHz), with a resolution of 0.123 cm−1 (3.7 GHz), at a rate of 72 spectra per second. The quasioptical system for collecting the light and transporting it through the interferometer to the detector has been designed using the concepts of both Gaussian and geometrical optics. The commercial FMI was custom made for this project and is the state of the art for this type of specialized instrument. The diagnostic system is described and an error propagation analysis of the absolute calibration process is given. Examples of ECE spectra measured in two polarization directions are given and electron temperature profiles derived from each of them are compared.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 3520-3523 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A 19-channel grating polychromator is developed to measure the temporal evolution of the electron cyclotron emission spectrum in the second and third harmonics in MTX tokamak with an aim to determine the electron temperature in ohmically heated thermal plasmas as well as the electron energy distribution function in gyrotron and free-electron laser-pumped nonthermal plasmas. The spectrometer can cover a spectral range of about 0.3 to 1.4 mm and deliver a maximum spatial resolution of about 1 cm radially. A combination of a 90° off-axis paraboloidal mirror as the collimating element and a toroidal mirror to focus the diffracted beam yields images on the exit slits with a modest astigmatic distortion. Liquid-helium-cooled InSb detectors are installed in nine channels and associated electronics are optimized for a very low noise and fast response time ( ∼ 2 μs). A faster detector element, with response 〈 100 ns, is envisioned for the remaining ten channels.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A 19-channel grating polychromator is developed to measure the temporal evolution of the electron cyclotron emission spectrum in the second and third harmonics in the MTX tokamak with an aim to determine the electron temperature in ohmically heated thermal plasmas as well as the electron energy distribution function in gyrotron and free-electron laser-pumped nonthermal plasmas. The spectrometer can cover a spectral range of about 0.3 to 1.4 mm and deliver a maximum spatial resolution of about 1 cm radially. A combination of a 90° off-axis paraboloidal mirror as the collimating element and a toroidal mirror to focus the diffracted beam yields images on the exit slits with a modest astigmatic distortion. Liquid-helium-cooled InSb detectors are installed in nine channels and associated electronics are optimized for a very low noise and fast response time (∼2 μs). A faster detector element, with response 〈100 ns, is envisioned for the remaining ten channels.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    International journal of infrared and millimeter waves 2 (1981), S. 1123-1134 
    ISSN: 1572-9559
    Keywords: calibration ; standards ; calibrated sources ; calibrated detectors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This paper presents the results of a mail survey on the calibration and standards requirements of the millimeter submillimeter wave and far infrared research community. Brief accounts of the work in this area that is currently in progress at NBS and NPL are included.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...