Excitement at CERN

[TheGreenGoblin]

Scientists at the Large Hadron Collider near Geneva have spotted an unusual signal in their data that may be the first hint of a new kind of physics.

The LHC collaboration, one of four main teams at the LHC, analysed 10 years of data on how unstable particles called B mesons, created momentarily in the vast machine, decayed into more familiar matter such as electrons.

The mathematical framework that underpins scientists’ understanding of the subatomic world, known as the standard model of particle physics, firmly maintains that the particles should break down into products that include electrons at exactly the same rate as they do into products that include a heavier cousin of the electron, a particle called a muon....

Further exciting detail here...

[TheGreenGoblin]

Some interesting comments on CERN, Sabine Hossenfelder (for whom I have developed a schoolboy crush) and sundry particular stuff.

https://www.math.columbia.edu/~woit/wordpress/?p=12019



Give it to me straight Sabine, I can take it!

[TheGreenGoblin]

From the link above...

Nima Arkani-Hamed is one of the leading particle physics phenomenologists of the generation. He is concerned with the relation between theory and experiment. His research has shown how the extreme weakness of gravity, relative to other forces of nature, might be explained by the existence of extra dimensions of space, and how the structure of comparatively low-energy physics is constrained within the context of string theory. He has taken a lead in proposing new physical theories that can be tested at the Large Hadron Collider at CERN in Switzerland...

The theory that the very weak force associated with gravity may be because gravity is mediated through one or more extra dimensions has been challenged recently due to https://en.wikipedia.org/wiki/LIGO.

How many dimensions does the universe have>

And my favourite Aussie (apart from our respected members here, of course) on why gravity may not be being mediated/dispersed through an additional, or additional, dimension(s) ...

[TheGreenGoblin]

And then ...

[TheGreenGoblin]

There are many different kinds of quarks, some of which are unstable and can decay into other particles. The new result relates to an experimental anomaly that was first hinted at in 2014, when LHCb physicists spotted “beauty” quarks decaying in unexpected ways.

Specifically, beauty quarks appeared to be decaying into leptons called “muons” less often than they decayed into electrons. This is strange because the muon is in essence a carbon-copy of the electron, identical in every way except that it’s around 200 times heavier.

You would expect beauty quarks to decay into muons just as often as they do to electrons. The only way these decays could happen at different rates is if some never-before-seen particles were getting involved in the decay and tipping the scales against muons.

While the 2014 result was intriguing, it wasn’t precise enough to draw a firm conclusion. Since then, a number of other anomalies have appeared in related processes. They have all individually been too subtle for researchers to be confident that they were genuine signs of new physics, but tantalisingly, they all seemed to be pointing in a similar direction.

The big question was whether these anomalies would get stronger as more data was analysed or melt away into nothing. In 2019, LHCb performed the same measurement of beauty quark decay again but with extra data taken in 2015 and 2016. But things weren’t much clearer than they’d been five years earlier.

New results
Today’s result doubles the existing dataset by adding the sample recorded in 2017 and 2018. To avoid accidentally introducing biases, the data was analysed “blind” – the scientists couldn’t see the result until all the procedures used in the measurement had been tested and reviewed.

Mitesh Patel, a particle physicist at Imperial College London and one of the leaders of the experiment, described the excitement he felt when the moment came to look at the result. “I was actually shaking”, he said, “I realised this was probably the most exciting thing I’ve done in my 20 years in particle physics.”

When the result came up on the screen, the anomaly was still there – around 85 muon decays for every 100 electron decays, but with a smaller uncertainty than before.

https://theconversation.com/evidence-of ... ngs-157464

[TheGreenGoblin]

Belle II will tell us more... (maybe)!

The Belle II experiment is a particle physics experiment designed to study the properties of B mesons (heavy particles containing a bottom quark). Belle II is the successor to the Belle experiment, and is currently being commissioned at the SuperKEKB[1] accelerator complex at KEK in Tsukuba, Ibaraki Prefecture, Japan. The Belle II detector was "rolled in" (moved into the collision point of SuperKEKB) in April 2017.[2][3] Belle II started taking data in early 2018.[1] Over its running period, Belle II is expected to collect around 50 times more data than its predecessor due mostly to a factor 40 increase in instantaneous luminosity provided by SuperKEKB over the original KEKB accelerator.

https://en.wikipedia.org/wiki/Belle_II_experiment

[TheGreenGoblin]

Paul Dirac would be pleased...

CERN’s Antimatter Factory is the only place in the world where low-energy antiprotons – the antimatter counterparts of protons – are produced. But in the not-so-distant future it could also be the first place to dispatch trapped antiprotons to another location. On 17 March 2021, the CERN Research Board approved the development of two new experiments to carry antiprotons from the Antimatter Factory to other facilities, for antimatter and nuclear-physics studies. BASE-STEP and PUMA, as the experiments are called, are compact enough to be transported in a small truck or van.

BASE-STEP is based on the BASE experiment – a set-up of traps to store and study in detail antiprotons produced at the Antimatter Factory. Using this set-up, the BASE team measures the properties of the antiproton and compares them with those of the proton to see if there are differences between the two – if found, such differences could shed light on the imbalance between matter and antimatter in the universe. BASE has been performing ever more precise antiproton measurements, but the precision of these measurements is limited by disturbances to the set-up’s magnetic field caused by the magnetic environment of the Antimatter Factory.

BASE-STEP is a variant of the BASE set-up that has been designed to be carried to a facility at CERN or elsewhere, one that has a calmer magnetic environment and thus allows higher-precision measurements to be made. The device will feature a first trap to receive and release the antiprotons produced at the Antimatter Factory and a second trap to store the antiprotons.

PUMA is based on a different transportable antiproton trap system and has a different scientific goal. It will transport antiprotons from the Antimatter Factory to CERN’s nuclear-physics facility, ISOLDE, for investigation of exotic nuclear-physics phenomena. It will consist of a first trapping zone to stop antiprotons, and a second trapping zone to host collisions between the antiprotons and radioactive atomic nuclei that are routinely produced at ISOLDE but decay too rapidly to be transported anywhere themselves.

Analysis of the outcome of these collisions, which will be detected by a particle detector surrounding the collision zone, will help researchers determine the relative densities of protons and neutrons at the surface of nuclei. These densities could reveal whether the nuclei have exotic properties such as thick neutron “skins” or extended halos of protons or neutrons around their core. Such knowledge could shed light on the interior of neutron stars.

PUMA and BASE-STEP are expected to be operational in 2023.

https://home.cern/news/news/physics/cer ... antimatter

[TheGreenGoblin]

[OFSO]

Who would have thought it?

[TheGreenGoblin]

Natural particle accelerators that produce high energy particle showers, usually in the 1 Giga Electron Volt Range, are not uncommon, arriving at lower energies from the sun, and at much higher energies from far out in the cosmos from places like the Crab Nebula and so on. The power of these particles falls off exponentially as they blast into the atoms in the atmosphere but present a real threat to electronic equipment, humans in low earth orbit, or future inter galactic travelers.

Many astronauts have noted cosmic ray visual phenomena. The actual physiological causes of the lights or scintillations are complex and may even be caused by physical phenomena such as Cherenkov radiation (where the particles travel faster than the speed of light for the specific medium, like the eyeball for example, in that specific medium (mostly water in this case).

Who knows, maybe we will all be snuffed out by a gamma ray burst in the next billion years or so...




A good CERN article on cosmic rays

[TheGreenGoblin]

Scientists have spotted one of the largest stellar flares ever recorded in our galaxy. The jets of plasma shot outward from the sun's nearest neighbor, the red dwarf star Proxima Centauri. The flare, which was around 100 times more powerful than any experienced in our solar system, could change the way scientists think about solar radiation and alien life.

Proxima Centauri is a red dwarf — the smallest, dimmest and most common type of main sequence stars in the galaxy — located approximately 4.25 light-years from Earth. Its mass is only one-eighth of the sun's, and it is orbited by two exoplanets. One of these planets, Proxima Centauri b, is considered to be Earth-like and lies within the star's habitable zone — the distance from a star that could support the development of life, according to the researchers.

In a new study, researchers used nine ground and orbital telescopes — including the Hubble Space Telescope, the Atacama Large Millimeter/submillimeter Array and NASA's Transiting Exoplanet Survey Satellite — to closely monitor Proxima Centauri for a total of 40 hours over several months in 2019. On May 1, 2019, the team captured the mega flare, which shone for just 7 seconds and was mainly visible in the ultraviolet spectrum.


"The star went from normal to 14,000 times brighter when seen in ultraviolet wavelengths over the span of a few seconds," lead author Meredith MacGregor, an astrophysicist at the University of Colorado Boulder, said in a statement.

https://www.space.com/proxima-centauri- ... wsource=cl

The power of this flare and type of radiation it emitted could change what we know about red dwarfs and the chances of life developing on the planets that orbit them.

Millimetre band high powered electromagnetic waves... not particles per se but given high enough enough energy states (gamma rays, i.e. very high energy photons) and according to E=MC2 the energy can transmute into particles...

Pair production

[Boac]

Does that mean that any life that may have existed on Proxima Centauri b disappeared on Feb 1 2015?

[TheGreenGoblin]

Does that mean that any life that may have existed on Proxima Centauri b disappeared on Feb 1 2015?

Well any life in line with the beam of energy within a couple of million kilometres would have been snuffed out around then. As you say!

I think the fact that a red dwarf created such a powerful flare, is likely to make astronomers likely to review their predictions about habitable planets around such stars!