The past 12 months was an enormous win for particle physics, as experiments and nature conspired to supply some truly stunning results. Listed here are the most important stories concerning the smallest particles from 2023.Â
1. Here comes the sun goddess
In 1992, astronomers were stunned to find what they later named the Oh-My-God particle, a cosmic ray streaking into Earth’s atmosphere with a blistering 320 exa-electron-volts (EeV) of energy. On a human scale, that is not an enormous number — roughly the energy of a dropped basketball hitting the bottom. But for subatomic particles, it’s gigantic, far outpacing even our strongest collider experiments. And this past 12 months, the OMG particle got a partner: a 240 EeV particle dubbed Amaterasu, named after the goddess of the sun in Japanese mythology. Discovered with the Telescope Array Project in Utah, the brand new particle joins a rarefied list of ultra-relativistic high-energy cosmic rays. These rare particles come from essentially the most energetic events within the universe but are ultimately mysterious. For instance, Amaterasu appeared to return from the direction of the Local Void, an enormous batch of nothing in our cosmological neighborhood.
Read more here: High-energy ‘sun goddess’ particle opens possibilities for brand new physics, exciting scientists
2. Who you gonna call? Ghost particles
Astronomers world wide are on the hunt for neutrinos. Â These “ghost particles” are produced in all styles of nuclear and high-energy reactions, but they infrequently interact with normal matter. So, to catch neutrinos, astronomers have turned to massive observatories, just like the IceCube Neutrino Observatory, which turns a whole cubic kilometer of the Antarctic ice sheet right into a neutrino detector. Using that sensitive instrument, this 12 months astronomers announced that our own Milky Way galaxy is producing neutrinos by the bucketful. While we have long known that other, more distant galaxies produce copious amounts of neutrinos, this was the primary direct evidence that our galaxy does, too, thus opening up a brand-new pathway in neutrino science.
Read more here: Scientists find ‘ghost particles’ spewing from our Milky Way galaxy in landmark discovery (video)
3. Feel the beat
Pulsars are already known to be amazing objects. They’re formed from neutron stars, that are the leftover cores of dead stars. They will compress several times the mass of the sun right into a volume no greater than a city. The fastest ones spin faster than your kitchen blender. Sometimes, they shoot out beams of radiation, and when those beams occur to clean over Earth, we call them pulsars. This 12 months, astronomers added one other superlative: essentially the most energetic gamma-ray photons ever detected from a pulsar. Using the High Energy Stereoscopic System observatory in Namibia, the astronomers saw the photons coming from a pulsar positioned about 1,000 light-years away within the direction of the constellation Vela. A single photon at these energies is over 2 million times more powerful than the photons related to a typical solar flare — so it’s a great thing they were generated up to now away.Â
Read more here: Pulsar surprises astronomers with record-breaking gamma-rays
4. And now, the BOAT
Speaking of gamma-rays, pulsars aren’t the one astronomical object able to blasting them out. The truth is, some explosions are so intense that they are known appropriately as gamma-ray bursts. In 2022, astronomers observed the brightest gamma-ray burst ever seen, which they dubbed the “BOAT,” for  “brightest of all time.” And in 2023, a distinct team of astronomers determined that the BOAT, which originated in a galaxy behind the Milky Way, was powerful enough to disturb the upper layer of Earth’s atmosphere. The extraordinary radiation affected the ionosphere, which sits between an altitude of 31 and 217 miles (between 50 and 350 kilometers). The effect wasn’t very big, however the undeniable fact that there was any effect in any respect is surprising, the team said.
Read more here: Record-breaking ‘BOAT’ gamma-ray burst managed to disturb Earth’s atmosphere
5. Antigravity doesn’t exist
Antimatter is similar to normal matter, except it has an opposite charge. For instance, a positron has the identical mass and spin as an electron, but has a positive charge slightly than a negative one. First discovered within the early twentieth century, antimatter is a significant cornerstone of theoretical physics. But besides the charge, just how similar are antimatter and normal matter? This 12 months, physicists determined that, yup, all of it acts the identical, especially in response to gravity.Â
General relativity says that antimatter and matter should behave the exact same, but no conclusive tests had been performed until this 12 months. It is not exactly a surprising result, however it’s good to ascertain these sorts of things off the list. In spite of everything, nature has loads of surprises for us, and also you never know where you would possibly find them.
Read more here: Antimatter responds to gravity like Einstein predicted, major CERN experiment confirms
6. The neutrino factory
Neutrinos are available in all styles of energies and from quite a lot of exotic sources. In 2023, astronomers learned of another: giant black holes. The black holes themselves don’t create neutrinos — in spite of everything, nothing can escape their gravitational clutches — however the gas swirling into their gaping maws definitely can. There, the plasma whips as much as a healthy fraction of the speed of sunshine and heats as much as trillions of degrees. That is good enough energy to supply all styles of crazy particles, including neutrinos, which astronomers found always washing over Earth.
Read more here: These supermassive black hole jets may pelt Earth with ‘ghost particles’
7. Dark matter mysteries
A lot of the matter within the universe is a mysterious type of matter generally known as dark matter, which we will detect only not directly via its gravitational influence on galaxies and the larger universe. There isn’t any altered theory of gravity that may explain the outcomes, so our current best guess is that dark matter is a few kind of unknown particle.Â
Scientists have been trying to find signs of this particle with detectors scattered world wide, and this 12 months, the Super Cryogenic Dark Matter Search collaboration announced … that they have not found it. This is not a nasty thing; the team did provide tighter constraints on what dark matter , which helps narrow down future searches — however the hunt continues.
Read more here: We still do not know what dark matter is, but here’s what it is not
8. When darkness consumes the sunshine
Dark matter is so mysterious that there could also be whole latest areas of physics which can be currently invisible to us. For instance, there could possibly be a brand new, fifth force of nature that operates only amongst different sorts of dark matter particles. This force would want its own carrier, which has been dubbed the “dark photon,” because that sounds really epic. This 12 months, a team of physicists shed some light (pun intended) on how these dark photons might work and, more importantly, on how we’d give you the option to detect them. Any theoretical insight here helps tremendously, as we’d like all the assistance we will get.
Read more here: Hypothetical ‘dark photons’ could make clear mysterious dark matter
9. His dark(er) materials
The world of dark matter can get even weirder. Not satisfied with only one form of particle? A brand new force of nature not enough? Well, how about a whole dark periodic table, with different “species” of dark matter particles interacting in their very own elaborate, invisible dance? This results in a deeply hypothetical idea generally known as dark atoms, where dark matter particles bundle up together within the hearts of galaxies. In accordance with latest research this 12 months, these dark atoms can go on to influence the speed of star production of their host galaxies — a potentially observable effect.Â
Read more here: Dark matter atoms may form shadowy galaxies with rapid star formation
10. Bubbletron mania
The early universe really knew find out how to throw a celebration. Throughout the first second after the Big Bang, the forces of nature split off from their united state, creating the cosmos that we all know and love today. These “splittings” were violent and energetic, and so they didn’t occur unexpectedly across the universe. As each force broke off, bubbles of the brand new reality formed, expanded and collided with one another. This 12 months, physicists discovered that the colliding bubbles would make for excellent particle accelerators. Dubbed “bubbletrons,” they simply might be accountable for the creation of many of the particles we’re conversant in.
Read more here: Giant ‘bubbletrons’ shaped the forces of the universe moments after the Big Bang
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11. Runaway sun
The sun is our closest star, so it is also our nearest laboratory for stellar physics. This 12 months, using the High-Altitude Water Cherenkov Observatory in Mexico, astronomers discovered that our star is much more energetic than we previously thought. The sun is perfectly able to generating excess gamma-rays, the highest-energy type of radiation. While that radiation doesn’t harm us directly, it does show that there is still loads to learn concerning the sun.
Read more here: Sun blasts out highest-energy radiation ever recorded, raising questions for solar physics