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GSMP-20GS

Description
The GSMP-20GS is the highest
sensitivity total magnetic field measuring device ever
developed. The GSMP-20GS produces 0.1 pT p-p sensitivity
(0.0001 nT p-p) at a sampling rate of 20 Hz, averaged
over a 1 second interval.
The GSMP-20GS Potassium
Supergradiometer is well over an order of magnitude more
sensitive than any other gradiometer in existence. The
GSMP-20GS was developed in response to the United State
Geological Survey's (USGS) requirement for an ultra-high
sensitivity magnetic gradiometer.
It is in part the GSMP-20GS's
larger sensors that provide sensitivities demanded by
the ultra-sensitive gradiometer system.
The GSMP-20GS operates on
principles similar to other alkali vapour magnetometers,
but benefits from the unique nuclear properties of
Potassium.
The GSMP-20GS is comprised of:
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rugged 3.5" x 19"
rack-mountable chassis, containing ultra-high
sensitivity gradiometer signal processor
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LCD display & programmable
RS-232 output port
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External Potassium Lamp
assembly
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External sensor electronics
assembly
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two (2) GSMP-20GS spherical
sensors, measuring 15 cm in diameter
The GSMP-20GS is fully compatible
with AirNAV airborne data acquisition and navigation
system.

Event of 0.0001 nT p-p recorded by GSMP-20GS
Ultra-High Sensitivity Potassium SuperGradiometer
(object at 40 metres from GSMP-20GS sensor)
Features
Some of the important benefits of
the GSMP-20GS optically pumped supergradiometer include:
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highest sensitivity ever
developed
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best absolute accuracy
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almost no orientation errors
GSMP-20GS Advantages
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GSMP-20GS sensors have the
highest absolute accuracy (varying by no more than ±
0.1 nT between sensors) critical for ultra-high
sensitivity gradiometer measurements
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GSMP-20GS does not require
regular calibrations
Applications
The long term stability, high
sensitivity and fast response to the changing magnetic
field make the GSMP-20GS ideal for a wide variety of
applications, such as:
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airborne magnetic gradient
surveying
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ordnance (weapons) detection
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shallow water marine craft
monitoring
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earthquake prediction
Additional Options
Specialized airfoil assemblies that
can house up to four SuperGradiometer sensors capable of
measuring magnetic gradient in up to three directions at
once in airborne surveys.
Benefits of the nuclear properties
of Potassium - Gradiometer Applications
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absolute accuracy - the
GSMP-20GS's unmatched absolute accuracy (a variance
of only ± 0.1 nT between any GSMP-20GS sensors) is
critical for ultra-high sensitivity gradiometer
measurements.
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sensitivity - inherent
potential sensitivity results from the nuclear
properties of potassium, is realized by
exceptionally narrow spectral ESR lines of 0.1-0.15
nT
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insensitivity to orientation -
virtually zero heading error resulting from the
nuclear properties of potassium
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Specifications of the GSMP-20GS Potassium
SuperGradiometer |
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Resolution |
0.001 pT for up to 20 readings per sec |
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Noise Envelope: |
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0.02 - 0.2 Hz |
0.02 pT rms |
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1 reading per
sec |
0.03 pT/vHz |
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Reading intervals |
0.05, 0.1, 0.2, 0.5 & 1 sec (others optional) |
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Absolute Accuracy |
0.2 nT |
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Time base stability |
0.01 ppm over –40ºC - +85ºC. |
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Long term stability |
1
pT/day (aging 1 ppm per year) |
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Tuning Wideband system |
no
tuning |
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Range |
10,000 to 100,000 nT |
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Sensor Orientation |
45º ± 35º off the magnetic field direction |
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Analog Output |
1
channel of magnetic field & 1 channel of
gradient
1, 10 & 100 pT. 1, 10, 100 nT & 1 mT (Selectable
full scale) |
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Output |
Digital Output Serial RS232C with programmable
parameters, Visual Output Alphanumeric LCD, 11
digit magnetic field, 7 digit magnetic gradient |
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Temperature Range |
-40º to + 55ºC |
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Console Dimensions & Weight |
483 x 89 x 406 mm / 6.6 kg (19" x 3.5" x 16") |
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Sensor Electronics Console Dimensions & Weight |
100 x 50 x 50 mm / 1.0 kg |
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Sensor Dimensions & Weight |
26.3 cm dia. x 23 cm / 6.0 kg |
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Lamp Assembly |
17
cm x 9 cm dia. |
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Cable Lengths User specified |
1
- 300 m |
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Power Requirements |
Ex. input voltage 22-32V, 12W ave., 40 W max. |
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