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From posting at Slashdot:
“A new study finds the highest-energy cosmic rays to bombard Earth come from galaxies far, far away. Space.com reports: The sun emits relatively low-energy cosmic rays. However, for more than 50 years, scientists have also detected ultra-high-energy cosmic rays, ones far beyond the capability of any particle accelerator on Earth to generate. One way to discover the origins of ultra-high-energy cosmic rays is to study their directions of travel. However, ultra-high-energy cosmic rays only rarely strike Earth’s atmosphere, with one hitting any given area about the size of a soccer field about once per century, the researchers said. In order to detect ultra-high-energy cosmic rays, scientists look for the spray of electrons, photons and other particles that result when ultra-high-energy cosmic rays hit the top of Earth’s atmosphere. Each of these showers contains more than 10 billion particles, which fly downward in a disk shaped like a giant plate miles wide, according to the statement. Scientists examined the sprays from ultra-high-energy cosmic rays using the largest cosmic-ray observatory yet: the Pierre Auger Observatory built in the western plains of Argentina in 2001. It consists of an array of 1,600 particle detectors deployed in a hexagonal grid over 1,160 square miles (3,000 square kilometers), an area comparable in size to Rhode Island. A connected set of telescopes is also used to see the dim fluorescent light the particles in the sprays emit at night.

The researchers analyzed data collected between 2004 and 2016. During these 12 years, the scientists detected more than 30,000 ultra-high-energy cosmic rays. If ultra-high-energy cosmic rays came from the Milky Way, one might perhaps expect them to come from all across the sky, or perhaps mostly from the direction of the supermassive black hole at the galaxy’s center. However, the researchers saw that ultra-high-energy cosmic rays mostly came from a broad area of sky about 90 degrees away from the direction of the Milky Way’s core.”
Here: https://m.slashdot.org/story/331549

Sunscreen or “carbon tax” are NOT much good against cosmic rays

highest energy cosmic rays?? They dabbling in time travel.. again.

ICECUBE :

Astrophysics observatories using the Cherenkov technique to measure air showers are key to determine the properties of astronomical objects that emit Very High Energy gamma rays, such as supernova remnants and blazars.

The detectors must be shielded by a large shield mass, and so are constructed deep underground, or underwater. They record upward going muons in charged current muon neutrino interactions. The detectors consist of an array of photomultiplier tubes (PMTs) housed in transparent pressure spheres which are suspended in a large volume of water or ice. The PMTs record the arrival time and amplitude of the Cherenkov light emitted by muons or particle cascades. The trajectory can then usually be reconstructed by triangulation if at least three “strings” are used to detect the eventsAstrophysics observatories using the Cherenkov technique to measure air showers are key to determine the properties of astronomical objects that emit Very High Energy gamma rays, such as supernova remnants and blazars.

Neutrinos are electrically neutral leptons, (A lepton is an elementary, half-integer spin (spin ?1/2) particle that does not undergo strong interactions.) and interact very rarely with matter. When they do react with the molecules of water in the ice, they can create charged leptons (electrons, muons, or taus). These charged leptons can, if they are energetic enough, emit Cherenkov radiation. This happens when the charged particle travels through the ice faster than the speed of light in the ice, similar to the bow shock of a boat traveling faster than the waves it crosses. This light can then be detected by photomultiplier tubes within the digital optical modules making up IceCube.

Since neutrinos are also created in the cores of stars (as a result of stellar fusion), the core can be observed using neutrino astronomy. Other sources of neutrinos- such as neutrinos released by supernovae – have been detected.

There are currently goals to detect neutrinos from other sources, such as Active Galactic Nuclei (AGN), as well as Gamma-ray bursts and Starburst galaxies.

Neutrino astronomy may also indirectly detect Dark Matter by looking for Weakly interacting massive particles. ((WIMPs) are hypothetical particles that are thought to const itute dark matter. As of today, there exists no clear definition of a WIMP, but broadly a WIMP is a new elementary particle which interacts via gravity and any other force (or forces), potentially not part of the standard model itself, which is as weak as or weaker than the weak nuclear force, but also non-vanishing in its strength))

In November 2013 it was announced that IceCube had detected 28 neutrinos that likely originated outside of the Solar System. The IceCube project is part of the University of Wisconsin–Madison projects developed and supervised by the same inst itution, while collaboration and funding is provided by numerous other universities and research inst itutions worldwide

Indirect dark matter searches

Weakly interacting massive particle ((WIMPs) are hypothetical particles that are thought to const itute dark matter.
There exists no clear definition of a WIMP, but broadly a WIMP is a new elementary particle which interacts via gravity and any other force (or forces), potentially not part of the standard model itself, which is as weak as or weaker than the weak nuclear force, but also non-vanishing in its strength))

Dark matter could be gravitationally captured by massive objects like the Sun and accumulate in the core of the Sun. With a high enough density of these particles, they would annihilate with each other at a significant rate. The decay products of this annihilation could decay into neutrinos, which could be observed by IceCube as an excess of neutrinos from the direction of the Sun.
This technique of looking for the decay products of WIMP annihilation is called indirect, as opposed to direct searches which look for dark matter interacting within a contained, instrumented volume.
Solar WIMP searches are more sensitive to spin-dependent WIMP models than many direct searches, because the Sun is made of lighter elements than direct search detectors (e.g. xenon or germanium).

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https://phys.org/news/2006-01-south-pole-neutrino-detector-yield.html :

Researchers at Northeastern University and the University of California, Irvine say that scientists might soon have evidence for extra dimensions and other exotic predictions of string theory. Early results from a neutrino detector at the South Pole, called AMANDA, show that ghostlike particles from space could serve as probes to a world beyond our familiar three dimensions, the research team says.
To find clues to support string theory and other bold, new theories, we need to study how matter interacts at extreme energies,” said Anchordoqui. “Human-made particle accelerators on Earth cannot yet generate these energies, but nature can in the form of the highest-energy neutrinos.”

n recent decades, new theories have developed – such as string theory, extra dimensions and supersymmetry – to bridge the gap between the two most successful theories of the 20th century, general relativity and quantum mechanics.
Quantum mechanics describes three of the fundamental forces of nature: electromagnetism, strong forces (binding atomic nuclei) and weak forces (seen in radioactivity). It is, however, incompatible with Einstein’s general relativity, the leading description of the fourth force, gravity.
Scientists hope to find one unified theory to provide a quantum description of all four forces.

Clues to unification, scientists say, lie at extreme energies. On Earth, human-made particle accelerators
have already produced energies at which electromagnetic forces and weak forces are indistinguishable.
Scientists have ideas about how the next generation of accelerators will reveal that strong forces are
indistinguishable from the weak and electromagnetic at yet higher energies.
Yet to probe deeper to see gravity’s connection to the other three forces, still higher energies are needed.

“The neutrinos accelerated in the cosmos to energies unattainable on Earth can detect the ‘footprint’ of new physics,” said Goldberg. “The ‘body’ responsible for the footprint can then emerge through complementary experiments at the new generation of human-made colliders. On all fronts, it is an exciting era in high-energy physics.”

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https://www.newscientist.com/article/mg19025521.600-at-last-a-way-to-test-time-travel/