Transcript Document

Mica track-etch detector
It is nothing simpler like a track-etch detector !
It is a passive alpha particle detector, used as
passive radon detector, ideal e.g. for long-term
radon test.
How it works? The alpha radiation, which comes
from radon and its progeny does microscopic
damage to the surface of mica detector. After
chemical etching the damaged area is enlarged
and seen as tracks. The tracks can be counted and
related to the radon concentration in the air in
which the detector was exposed.
more words about track-etch detectors
When a charged particle slows down and stops in a solid, the energy
that it deposits along its track can cause permanent damage in the
material. It is difficult to observe direct evidence of this local damage,
even under careful microscopic examination. In certain dielectric
materials, however, the presence of the damaged track can be revealed
through chemical etching (erosion) of the material surface using an
acid or base solution. If charged particles have irradiated the surface
at some time in the past, then each leaves a trail of damaged material
that begins at the surface and extends to ...
A solid state nuclear track detector or SSNTD (also known as an
etched track detector or a dielectric track detector, DTD) is a sample
of a solid material (photographic emulsion, crystal, glass, plastic or mica)
exposed to nuclear radiation.
The tracks of nuclear particles are etched faster than the bulk material,
and the size and shape of these tracks yield information about the mass,
charge, energy and direction of motion of the particles. The main
advantages over other radiation detectors are the detailed information
available on individual particles, the persistence of the tracks allowing
measurements to be made over long periods of time, and the simple,
cheap and robust construction of the detector