“They’re
the most mysterious type of particle we know of”
Dr Juan Collar, a
physicist at the University of Chicago working at the Oak Ridge National
Laboratory in Tennessee
Neutrinos
are tiny subatomic particles that interact so weakly with matter that they pass
through the entire planet then fly silently back into the cosmos. However, it
seems that that trillions of them that pass through the earth every day do
interact with the Nucleus of atoms.
Physicist
Juan Collar and a group of Scientist at Oak Ridge National Laboratory in
Tennessee have observed this interaction with the nucleus as reported in the
article “Physicist
capture the elusive Neutrino smacking into an Atom's Core”,
published 08.03.17 by Sophia Chen, Wired.
This
process, called coherent elastic scattering, was observed using a toaster-sized
detector made of cesium iodide (CeI) crystals. They observed their apparatus
over a 15 month period during which trillions of neutrinos through the
apparatus, detecting neutrinos interacting with the nucleus of the cesium
iodide atoms in their crystal lattice 134 times.
In
the interaction, the Neutrino would produce 10 photons’ worth of dim light,
literally shedding light on the nature of these elusive particles and potentially
opening up a pathway to studying Dark Matter. This is interesting to me, as
according to the Standard Model, Neutrinos should have no mass, albeit in 1998,
physicists found that neutrinos do indeed have mass.
So
where did they get so many neutrinos to fit through their itty-bitty apparatus?
And why did they succeed when other larger detectors have failed?
Oak Ridge National
Laboratory and Neutrinos - How to use a Toaster to catch coherent elastic
scattering in Sub-atomic particles
Neutrinos
and nuclei are quantum mechanical particles. Long considered massless they have
never been observed to interact with matter.
But
when they get close, the transfer energy to a particle called a Z boson, which
then goes on to interact with the Nucleus of an atom, made up of protons and
neutrons. The Nucleus, however, vibrates upon the impact of these particles,
recoils and releases energy in the form of photons. It is these photons that
Juan Collar and his team at Oak Ridge National Laboratory detected.
To
make sure that their experimental result was not the result of random Cosmic
Noise and Neutrinos just passing through earth as usual, they put 20 feet of
steel and a hundred feet of concrete and gravel between the detector and the
neutrino source. The S/N Ratio was thus increased, reducing the odds that the
signal was due to random noise by 1 in 3.5 million, making their discovery one
for the history books.
Coherent
elastic scattering has long been predicted by the Standard Model; this is the
first time an experiment has been done that observes this rare phenomenon. It
also proves that Neutrinos do indeed have mass, and quite enough to coax the
nucleus of cesium iodide (CeI) crystals to produce photons.
So
what does this mean for subatomic particles in general?
Neutrinos and Dark
Matter - Neutrino variants studied and Dark Matter via Neutrino Traps
Oak
Ridge National Laboratory can adapt their apparatus to study other sub-atomic
particles that defy the Standard model. Such particles include other members of
the neutrino family:
1. Sterile
neutrino
2. Electron
neutrino
3. Tau
neutrino
4. Muon
neutrino
The
detector could allow the neutrino to travel a longer distance through air
before reaching the detector; if fewer collisions are detected, it may be
evidence of sterile neutrinos. It can also be used to detect Dark Matter, which
makes up 23% of the observable universe aside from regular baryonic matter i.e.
protons, electrons, etc but like Neutrinos interact very little with the nuclei
of atoms.
First,
though, Physicists would have to figure out how to filter out particles that
basically travel through everything to detect the even more elusive particles.
One idea is to create a Neutrino trap.
This
can be done by ionizing Hydrogen atoms arranged in a crystal lattice at 0 Kelvin (-273 C),
a form of hydrogen called Metallic Hydrogen. This hydrogen then deliberately
colliding them with neutrinos in a very strong magnetic field and at 0 Kelvin (-273 C) temperatures.
The interaction should trap the neutrinos, Z Boson as well as photons emitted; anything coming form that bubbleing quantum soup of subatomic particles should be Dark Matter.....or something new that physicists’ have yet to detect.
Still,
this discovery of coherent elastic scattering using apparatus no bigger than a
Toaster Oven should open up the door for the design of similar detectors to
fill in the holes in the Standard Model!
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