Antimatter

It's extremely rare and usually exists for just 142 billionths of a second.

Positronium can generate huge amounts of energy. It can shed light on 'antimatter' which existed at the beginning of the Universe, and studying it could revolutionise physics, cancer treatment, and maybe even space travel.

But until now the elusive substance has been almost impossible to analyse because its atoms move around so much.

Now scientists have a workaround - freezing it with lasers.

"Physicists are in love with positronium," said Dr Ruggero Caravita, who led the research at the European Organization for Nuclear Research (Cern), near Geneva. "It is the perfect atom to do experiments with antimatter."     READ MORE...

CERN's New Particle Collider

Preparations for a massive new particle smasher near Geneva are picking up speed. But the European-led project, which hopes to answer some of the biggest questions in physics, faces many obstacles, including competition from China.

In 2012 scientists at the European Organization for Nuclear Research (CERN) achieved a key breakthrough when they detected the elusive Higgs boson, an elementary particle that gives mass to all the others. This followed decades of work using accelerators such as the famed Large Hadron Collider (LHC), the world’s most powerful particle collider located north of Geneva.

Yet many fundamental questions about the universe remain unanswered: What constitutes dark matter? Why is our universe filled with matter and not antimatter? Or why do the masses of elementary particles differ so much?

The search for answers to these and other big physics questions requires another “leap to higher energies and intensities”, says CERN. The organisation wants to build a more powerful and precise successor to the LHC, which was conceived in the early 1980s and will complete its mission in 2040.

“We build these machines to explore the nature of the universe. It’s about going out into the unknown and exploring further,” says Mike Lamont, CERN’s director of accelerators and technology.

And so, following requests by the global physics community, plans for the so-called Future Circular Collider (FCC) have been taking shape over the past ten years.  READ MORE...

Matter in the Universe

Most matter in the universe cannot be seen — but its influence on the largest structures in space can.

Astronomers estimate that roughly 85% of all the matter in the universe is dark matter, meaning only 15% of all matter is normal matter. Accounting for dark energy, the name astronomers give to the accelerated expansion of the universe, dark matter makes up roughly 27% of all the mass energy in the cosmos, according to CERN (the European Organization for Nuclear Research).

Astronomers have a variety of tools to measure the total amount of matter in the universe and compare that to the amount of "normal" (also called "baryonic") matter. The simplest technique is to compare two measurements.

The first measurement is the total amount of light emitted by a large structure, like a galaxy, which astronomers can use to infer that object's mass. The second measurement is the estimated amount of gravity needed to hold the large structure together. 

When astronomers compare these measurements on galaxies and clusters throughout the universe, they get the same result: There simply isn't enough normal, light-emitting matter to account for the amount of gravitational force needed to hold those objects together.

Thus, there must be some form of matter that is not emitting light: dark matter.

Different galaxies have different proportions of dark matter to normal matter. Some galaxies contain almost no dark matter, while others are nearly devoid of normal matter. But measurement after measurement gives the same average result: Roughly 85% of the matter in the universe does not emit or interact with light.  READ MORE...

Exotic Pentaquark Particle Found

The LHCb collaboration has announced the discovery of a new pentaquark particle. The particle, named Pc(4312)+, decays to a proton and a J/ψ particle (composed of a charm quark and an anticharm quark). This latest observation has a statistical significance of 7.3 sigma, passing the threshold of 5 sigma traditionally required to claim a discovery of a new particle.

In the conventional quark model, composite particles can be either mesons formed of quark–antiquark pairs or baryons formed of three quarks. Particles not classified within this scheme are known as exotic hadrons. 

When Murray Gell-Mann and George Zweig proposed the quark model in their 1964 papers, they mentioned the possibility of exotic hadrons such as pentaquarks, but it took 50 years to demonstrate their existence experimentally. In July 2015, the LHCb collaboration reported the Pc(4450)+ and Pc(4380)+ pentaquark structures. 

The new particle is a lighter companion to these pentaquark structures and its existence sheds new light into the nature of the entire family.

The analysis presented today at the Rencontres de Moriond quantum chromodynamics (QCD) conference used nine times more data from the Large Hadron Collider than the 2015 analysis. The data set was first analysed in the same way as before and the parameters of the previously reported Pc(4450)+ and Pc(4380)+ structures were consistent with the original results. 

As well as revealing the new Pc(4312)+ particle, the analysis also uncovered a more complex structure of Pc(4450)+ consisting of two narrow overlapping peaks, Pc(4440)+ and Pc(4457)+, with the two-peak structure having a statistical significance of 5.4 sigma. More experimental and theoretical study is still needed to fully understand the internal structure of the observed states.

Read more on the LHCb website.

Giant Particle Accelerator

A radio frequency particle accelerator is displayed in an exhibition during a press tour at the European Organization for Nuclear Research (CERN) on the Future Circular Collider (FCC) feasibility study, in Geneva, on April 19, 2023. (Fabrice Coffrini/AFP)

GENEVA (AFP) — Europe’s CERN laboratory has taken its first steps toward building a huge new particle accelerator that would eclipse its Large Hadron Collider — and hopes to see light at the end of the tunnel.

The Future Circular Collider (FCC) particle smasher would be more than triple the length of the LHC, already the world’s largest and most powerful particle collider, constructed in the hope of revealing secrets about how the universe works.

The FCC would form a new circular tunnel under France and Switzerland, 91 kilometers (56.5 miles) long and about five meters (16 feet) in diameter.


“The goal of the FCC is to push the energy and intensity frontiers of particle colliders, with the aim of reaching collision energies of 100 tera electron volts, in the search for new physics,” CERN says.

The tunnel would pass under the Geneva region and its namesake lake in Switzerland, and loop around to the south near the picturesque French town of Annecy.

Eight technical and scientific sites would be built on the surface, with seven in France and one in Geneva, CERN engineer Antoine Mayoux told reporters this week.  READ MORE...

From the Dawn of Time

The particle was produced inside the Large Hadron Collider at CERN. (Image credit: Shutterstock)

Physicists at the world's largest atom smasher have detected a mysterious, primordial particle from the dawn of time.

About 100 of the short-lived "X" particles — so named because of their unknown structures — were spotted for the first time amid trillions of other particles inside the Large Hadron Collider (LHC), the world's largest particle accelerator, located near Geneva at CERN (the European Organization for Nuclear Research).

These X particles, which likely existed in the tiniest fractions of a second after the Big Bang, were detected inside a roiling broth of elementary particles called a quark-gluon plasma, formed in the LHC by smashing together lead ions. By studying the primordial X particles in more detail, scientists hope to build the most accurate picture yet of the origins of the universe. They published their findings Jan. 19 in the journal Physical Review Letters.
wie X particle's internal structure, which could change our view of what kind of material the universe should produce."

Scientists trace the origins of X particles to just a few millionths of a second after the Big Bang, back when the universe was a superheated trillion-degree plasma soup teeming with quarks and gluons — elementary particles that soon cooled and combined into the more stable protons and neutrons we know today.

Just before this rapid cooling, a tiny fraction of the gluons and the quarks collided, sticking together to form very short-lived X particles. The researchers don't know how elementary particles configure themselves to form the X particle's structure. But if the scientists can figure that out, they will have a much better understanding of the types of particles that were abundant during the universe's earliest moments.  READ MORE...

A New Force of Nature

The Large Hadron Collider (LHC) sparked worldwide excitement in March as particle physicists reported tantalizing evidence for new physics — potentially a new force of nature. Now, our new result, yet to be peer reviewed, from CERN’s gargantuan particle collider seems to be adding further support to the idea.

Our current best theory of particles and forces is known as the standard model, which describes everything we know about the physical stuff that makes up the world around us with unerring accuracy. The standard model is without doubt the most successful scientific theory ever written down and yet at the same time we know it must be incomplete.


Famously, it describes only three of the four fundamental forces – the electromagnetic force and strong and weak forces, leaving out gravity. It has no explanation for the dark matter that astronomy tells us dominates the universe, and cannot explain how matter survived during the big bang. Most physicists are therefore confident that there must be more cosmic ingredients yet to be discovered, and studying a variety of fundamental particles known as beauty quarks is a particularly promising way to get hints of what else might be out there.

Beauty quarks, sometimes called bottom quarks, are fundamental particles, which in turn make up bigger particles. There are six flavors of quarks that are dubbed up, down, strange, charm, beauty/bottom and truth/top. Up and down quarks, for example, make up the protons and neutrons in the atomic nucleus.

The LHCb experiment at CERN. Credit: CERN

Beauty quarks are unstable, living on average just for about 1.5 trillionths of a second before decaying into other particles. The way beauty quarks decay can be strongly influenced by the existence of other fundamental particles or forces. When a beauty quark decays, it transforms into a set of lighter particles, such as electrons, through the influence of the weak force. One of the ways a new force of nature might make itself known to us is by subtly changing how often beauty quarks decay into different types of particles.  TO READ MORE, CLICK HERE...

New Sub Atomic Particles

Physicists Just Found 4 New Subatomic Particles That May Test The Laws of Nature

PATRICK KOPPENBURG, THE CONVERSATION  --  5 MARCH 2021

This month is a time to celebrate. CERN has just announced the discovery of four brand new particles at the Large Hadron Collider (LHC) in Geneva.

This means that the LHC has now found a total of 59 new particles, in addition to the Nobel prize-winning Higgs boson, since it started colliding protons – particles that make up the atomic nucleus along with neutrons – in 2009.


Excitingly, while some of these new particles were expected based on our established theories, some were altogether more surprising.

The LHC's goal is to explore the structure of matter at the shortest distances and highest energies ever probed in the lab – testing our current best theory of nature: the Standard Model of Particle Physics. And the LHC has delivered the goods – it enabled scientists to discover the Higgs boson, the last missing piece of the model. That said, the theory is still far from being fully understood.

One of its most troublesome features is its description of the strong force which holds the atomic nucleus together. The nucleus is made up of protons and neutrons, which are in turn each composed of three tiny particles called quarks (there are six different kinds of quarks: up, down, charm, strange, top and bottom).



If we switched the strong force off for a second, all matter would immediately disintegrate into a soup of loose quarks – a state that existed for a fleeting instant at the beginning of the universe.

Don't get us wrong: the theory of the strong interaction, pretentiously called "quantum chromodynamics", is on very solid footing. It describes how quarks interact through the strong force by exchanging particles called gluons. You can think of gluons as analogues of the more familiar photon, the particle of light and carrier of the electromagnetic force.  SOURCE:  ScienceAlert.com