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A Century of particle detection
Cloud Chamber
Dark Matter Detector
PARTICLE DETECTORS are the tools that lead to
DISCOVERY of new particles, UNDERSTANDING of new
Physics and innovative TECHNOLOGY used in areas
like MEDICINE and SPACE-RESEARCH.
In the 21st century, detectors are used in
various forms (Dark Matter/ neutrino detectors)
or combined in to one mega-structure (CMS/ ATLAS)
to solve the biggest mysteries Dark Matter,
Super-symmetry, Quark-Gluons, etc.
A PHONON (sound/heat) detector It operates at
about 1/50th of degree above ABSOLUTE ZERO and
detects tiniest of tiny crystal vibrations,
through the use of SUPERCONDUCTING detection
technology called TRANSITION-EDGE SENSORS (TES).
The detector contains more than 4000 sensors,
each 100 times thinner than human hair. It
operates on the principle of extremely sharp
transition of the sensor
The CLOUD CHAMBER It started as an actual
atmospheric cloud-simulator, and found use in
Physics. IT GAVE THE VISUAL PROOF OF EXISTENCE
OF RADIATIONS, and was also used to detect FIRST
ANTI-PARTICLE in 1932 (Nobel prize 1936) -
POSITRON. Just as a plane leaves trail in sky
during cold winters, here, a tiny charged
particle causes water vapor to condense around it
and make observable moisture trails.
from zero to large resistance within a small
temperature change of 1/200th of a degree.
An IONIZATION COUNTER In this, an incoming
particle causes an electric signal. It is used
widely as a modern particle detector, due to its
HIGH SPEED of operation. The simple principle is
applied in devices as handy as the GEIGER
COUNTER (first made 1928) which can be hand-held
to detects presence of radioactive emissions.
Same idea, along with extra magnetic fields, is
used in complex multi-wire proportional chambers
of massive sizes in current multi-billion dollar
experiments.
Scintillation Light Detector
A SCINTILLATION COUNTER The sensor called
a scintillator, consists of a transparent crystal,
usually NaI (Sodium-Iodide), that GIVES OFF BLUE
LIGHT when struck by ionizing radiation. A
sensitive photomultiplier tube (PMT) amplifies
(10,000 times) the signal from the crystal. The
scintillation counter was invented in 1944 and is
widely used in most major experiments
Multi-wire Chamber
Ionization Counter