NUCLEAR PHYSICS: STUDY DATA FROM YEREVAN STATE UNIVERSITY UPDATE KNOWLEDGE OF NUCLEAR PHYSICS
Science Letter
August 5, 2008
According to recent research published in the journal Nuclear
Instruments & Methods in Physics Research Section a – Accelerators
Spectrometers Detectors and Associated Equipment, "A new class
super-broad band, nano-scale-resolution position sensor is tested. It
is used as an additional sensor in seismograph."
"It enables to extend the band and enhance the sensitivity of the
available technique by at least an order of magnitude. It allows
transferring of mechanical vibrations of constructions and buildings,
with amplitudes over 1 nm, into detectable signal in a frequency
range starting practically from quasi-static movements. It is based
on detection of position changes of a vibrating normal-metallic plate
placed near the flat coil-being used as a pick-up in a stable tunnel
diode oscillator. Frequency of the oscillator is used as a detecting
parameter, and the measuring effect is determined by a distortion of
the MHz-range testing field configuration near a coil by a vibrating
plate, leading to magnetic inductance changes of the coil, with a
resolution similar to 10 pH. This results in changes of oscillator
frequency. We discuss test data of such a position sensor, installed
in a Russian SM-3 seismometer, as an additional pick-up component,
showing its advantages compared to traditional techniques. We also
discuss the future of such a novel sensor involving substitution of
a metallic coil by a superconductive one and replacement of a tunnel
diode by an S/I/S hetero-structure-as much less-powered active element
in the oscillator, compared to tunnel diode," wrote S. Gevorgyan and
colleagues, Yerevan State University (see also Nuclear Physics).
The researchers concluded: "These may strongly improve the stability
of oscillators, and therefore enhance the resolution of seismic
techniques."
Gevorgyan and colleagues published their study in Nuclear Instruments
& Methods in Physics Research Section a – Accelerators Spectrometers
Detectors and Associated Equipment (A single-layer flat-coil-oscillator
(SFCO)-based super-broadband position sensor for nano-scale-resolution
seismometry. Nuclear Instruments & Methods in Physics Research Section
a – Accelerators Spectrometers Detectors and Associated Equipment,
2008;589(3):487-493).
For additional information, contact S. Gevorgyan, Yerevan State
University, Dept. of Physics, 1 Alex Manoogian St., Yerevan 0025,
Armenia.
The publisher’s contact information for the journal Nuclear Instruments
& Methods in Physics Research Section a – Accelerators Spectrometers
Detectors and Associated Equipment is: Elsevier Science BV, PO Box 211,
1000 AE Amsterdam, Netherlands.