GLORIA

GEOMAR Library Ocean Research Information Access

X
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
    A fast detector using stacked avalanche photodiodes for x-ray diffraction experiments with synchrotron radiation (1998)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 384-391 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We have developed a fast detector using stacked avalanche photodiodes (APDs) for x-ray diffraction experiments with synchrotron radiation. This detector has four independent channels of APDs, and the detector efficiency has reached 55% in all for 16.53 keV x rays. Since the dead time of the counting system is shorter than 4 ns, output rates of up to 4.5×108 counts/s have been obtained for 16.53 keV x rays. The dynamic range is more than 1010 in the multibunch mode of a storage ring. Pulse-height measurements at output rates of up to 108 counts/s were successfully carried out by sequential single-channel discrimination. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1148670
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Charged particle densities and kinetics in a radio-frequency SF6 plasma (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 7221-7230 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electron, negative ion, and positive ion densities in a capacitively-coupled radio-frequency (rf, 13.56 MHz) SF6 plasma have been investigated as functions of the pressure (30–700 mTorr) and rf power. The decay of the charged particle densities in the afterglow has also been studied to obtain information about their kinetics. The electron density was determined by using a microwave cavity resonance technique. Negative ions were detected by measuring the density of photodetached electrons produced by pulsed laser irradiation of the plasma. The positive ion density was obtained from Langmuir probe measurements. At a rf power of 0.13 W/cm2 and at low pressures ((approximately-less-than)100 mTorr) the positive ion density, which is virtually equal to the negative ion density, is found to be larger than the electron density by a factor of a few hundred; the ion/electron density ratio increases with increasing pressure to reach a value of a few thousand at high pressures. Wavelength-dependent photodetachment measurements indicate that the dominant contribution to the photodetachment signal at 266 nm comes from F−, but F− is a minor negative-ion species with respect to the density; that is, the photodetachment efficiency for the dominant negative ion species (supposed to be SF−5) is low. The recombination rate constant for F− (supposedly with SF+5) is suggested to be an order of magnitude larger than that for the dominant ion species, the latter being estimated to be slightly smaller than 10−7 cm3 s−1. © 1994 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358003
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Observation of resonant tunneling through single self-assembled InAs quantum dots using electrophotoluminescence spectroscopy (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 4332-4336 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The resonant tunneling through single InAs quantum dots embedded in an n-GaAs/i-Al0.38Ga0.62As/n-GaAs diode has been studied by using microscopic electrophotoluminescence spectroscopy. Many sharp luminescence lines which originated from single quantum dots were observed by injecting resonant electrons from the emitter to the dots. Bias dependence of a single luminescence line was investigated. The peak intensity showed triangular dependence which was similar to the current–voltage characteristics of electron resonant tunneling from three dimension to zero dimension. When the bias voltage was increased, the peak energy slightly shifted to a lower energy indicating the existence of Stark effect, and the linewidth slightly increased. The higher the luminescence energy was, the broader the linewidth was. This result agrees with the calculated resonant level width. The lifetime of resonant states was estimated to be 2.4–27 ps for luminescence linewidth of 250–22 μeV. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.373074
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Multipurpose four-circle diffractometer with a crystal analyzer for use with synchrotron radiation (1989)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 60 (1989), S. 2406-2409 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: This paper describes the performance of a four-circle diffractometer installed at the Photon Factory for extensive use with synchrotron radiation for various investigations in the field of solid state physics. Its main part is based on a Huber 5020.4 type diffractometer with a crystal analyzer designed for vertical diffraction plane attitude. The diffractometer is mounted on a carriage table, which can precisely adjust the position of the diffractometer with respect to the incident beam monochromatized by successive reflection from a pair of Si(111) crystals. With a perfect crystal used as the analyzer the large size of the ω and 2θ circles enables us to make high resolution (ΔQ/Q∼10−4) measurements of x-ray scattering intensity distribution from a single crystal. The large space in the center of the diffractometer permits us to put a pressurizing cell or a cryostat on the φ table for scattering measurements at controlled pressures and temperatures. Selected examples of the application are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1140731
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    X-ray area detector based on CCD readout for diffraction study (abstract) : Proceedings of the 4th International conference on synchrotron radiation instrumentation (1992)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 63 (1992), S. 659-659 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An x-ray area detector based on charged coupled device (CCD) readout has been designed and constructed for diffraction studies. Incident x-rays are converted to visible photons by a phosphor screen [Y2O2S or CsI(Na)] which is attached via fiber optic to the input surface of the demagnifying image intensifier with a 4:1 demagnification. The intensified visible image created on the output phosphor screen of the image intensifier is viewed through a 1:1 optical lens system by the cooled CCD (Thomson:THX31156) which has 1024×1024 pixels (pixel size: 19 μm×19 μm). The detector system should have the following characteristics: active area: 100 mm in diameter, spatial resolution: 0.1 mm×0.1 mm, detective quantum efficiency (DQE): about 70% for 8 keV, dynamic range: more than 104, readout time: 4 s. Nonuniformity of response due to the image intensifier is corrected by software. The CCD is cooled to −30° to −40° to reduce the dark current. The background noise level of the detector system corresponds to less than 10 x-ray photons per pixel. Detailed hardware and software configuration and measured performance of the system will be described. The system will be applied to small-angle x-ray scattering (SAXS) and protein crystallography.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1142682
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...