Science is the poetry of Nature.







Contributing Authors
Posts tagged "neutrinos"

Exotic particles called neutrinos have been caught in the act of shape-shifting, switching from one flavor to another, in a discovery that could help solve the mystery of antimatter.

Neutrinos come in three flavors — electron, muon and tau — and have been known to change, or oscillate, between certain flavors. Now, for the first time, scientists can definitively say they’ve discovered muon neutrinos changing into electron neutrinos.

The discovery was made at the T2K neutrino experiment in Japan, where scientists sent a beam of muon neutrinos from the J-PARC laboratory in Tokai Village on the eastern coast of Japan, streaming 183 miles (295 km) away to the Super-Kamiokande neutrino detector in the mountains of Japan’s northwest.

The researchers detected an average of 22.5 electron neutrinos in the beam that reached the Super-Kamiokande detector, suggesting a certain portion of the the muon neutrinos had oscillated into electron neutrinos; if no oscillation had occurred, the researchers should have detected just 6.4 electron neutrinos.

Strange Particles Shape-Shift From One Flavor to Another

Message Encoded in Neutrino Beam Transmitted through Solid Rock

Neutrinos are having a moment. They’re speeding across Europe (just how fast is under review), they’re changing flavors in China and, now, they’re carrying rudimentary messages through bedrock in Illinois.

A team of physicists encoded a short string of letters on a beam of neutrinos at Fermi National Accelerator Laboratory in Batavia, Ill., and sent the message to a detector more than a kilometer away. On the journey the neutrinos passed through 240 meters of solid rock, mostly shale. What was the word they transmitted in the preliminary demonstration? “Neutrino.” The experiment is described in a paper posted to the physics preprint server arXiv.org.

Continue Reading »

jtotheizzoe:

Even newer doubts cast on faster-than-light neutrinos experiment

Yep, even newer than last weeks supporting evidence!

Physicists are poking holes in this ship just as fast as the OPERA team can plug them! Despite last week’s new evidence in support of the faster-than-light (FTL) neutrino observations, a team of competing physicists claim new controversy.

The Icarus team, who share the CERN lab that made the original findings, claim that if a neutrino moved faster than light in this experiment, it would have spewed out a ton of energy in the form of electrons and positrons.

This is because when something moves faster than light in a medium like air or water (as opposed to a vacuum, like all the “theoretical” speeds assume), it energizes its medium … which you’d be able to detect. It’s related to Cherenkov radiation, which is why nuclear reactors glow blue when they are submerged in water. It works like this:

Fission -> Release of Beta Particles -> Faster Than Light Speed In Water -> Water Molecules Energized -> Blue Light Released

The Icarus team saw no such energy release from the OPERA experiment (which did not fly through a vacuum) and claims it must be an observational error.

Is Icarus flying too close to the Sun? Or is this a valid error? Time will tell.

For now, though, the plot thickens, and this guy has promised to eat his boxer shorts on live TV if OPERA holds up.

(via The Guardian, image via Fermilab)

(via jtotheizzoe)

cwnl:

Neutrinos: Everything You Need To Know

What exactly are they?

With a neutral charge and nearly zero mass, neutrinos are the shadiest of particles, rarely interacting with ordinary matter and slipping through our bodies, buildings and the Earth at a rate of trillions per second.

First predicted in 1930 by Wolfgang Pauli, who won a Nobel prize for this work in 1945, they are produced in various nuclear reactions: fusion, which powers the sun; fission, harnessed by humans to make weapons and energy; and during natural radioactive decay inside the Earth.

If they are so stealthy, how do we know they are there at all?

Wily neutrinos usually avoid contact with matter, but every so often, they crash into an atom to produce a signal that allows us to observe them. Fredrick Reines first detected them in 1956, garnering himself a Nobel prize in 1995.

Most commonly, experiments use large pools of water or oil. When neutrinos interact with electrons or nuclei of those water or oil molecules, they give off a flash of light that sensors can detect.

Where are these experiments found?

These days, a lot of expense and extreme engineering go into detectors that are sunk into the ground to shield them from extraneous particles that might interfere with them. For instance, OPERA, which detected the apparently faster-than-light neutrinos beamed from CERN, lies inside the Gran Sasso mountain in Italy. This works because neutrinos shoot straight through such shields.

Other detectors pick up naturally-produced neutrinos. One such detector – ANTARES – is miles under the Mediterranean Sea, while another, IceCube, is buried under Antarctic ice.

What’s cool about neutrinos?

Their stealth belies their potential importance. Take extra dimensions. Most particles come in two varieties: ones that spin clockwise and ones that spin anticlockwise. Neutrinos are the only particles that seem to just spin anticlockwise. Some theorists say this is evidence for extra dimensions, which could host the “missing”, right-handed neutrinos.

Anything else?

Unseen right-handed neutrinos may also account for mysterious dark matter. This is thought to make up 80 per cent of all matter in the universe and to stop galaxies from flying apart. The idea is that right-handed neutrinos might be much heavier than left-handed ones and so could provide the requisite gravity.

For More on Neutrinos, Read More Here