New detector finds gamma rays from surprising cosmic sources
Astrophysicist Cao Zhen opens a good steel hatch on a good windswept Tibetan Plateau and climbs down a good ladder into inky darkness. His flashlight picks out a boat floating on a pool of purified normal water above thousands of glittering orbs how big is beachballs.
He’s in the $175 million observatory which has already learned something tantalizing astronomers possibly before the observatory is technically total: bursts of gamma rays from space that may someday support explain how matter is established and distributed over the universe.
The Large High Altitude Air Shower Observatory, the largest machine of its kind, has detected a dozen resources of ultra high-energy gamma rays, according to a report in the journal Aspect, from what Cao calls “many hot spots,” in our Milky Way galaxy.
Gamma rays with such superior energy have never been detected before, and the results suggest these rays will come not simply from dying stars, but are also produced inside massive young stars.
“These results are really stunning - one of the most exciting I have ever seen,” said Alan Watson, an astrophysicist working with the Pierre Auger Observatory on Argentina.
Cao’s team traced 530 high-strength gamma rays to 12 sources including a massive cluster of young superstars called the Cygnus Cocoon and the interstellar cloud called the Crab Nebula.
Gamma rays are a kind of extreme radiation made by the latest and brightest explosions found in the universe, want when a large superstar implodes. Those implosions as well create the matter that make up planets - and everything that lives on them, including us. Of all electromagnetic waves in the universe, gamma rays possess the tiniest wavelengths and the most energy. They can release more energy in 10 seconds than our sun in 10 billion years.
The pool of purified water at LHAASO that Cao paddled across measures the subatomic shrapnel - the “air shower” in the observatory’s name - created when gamma rays and large energy particles called cosmic rays crash into the Earth’s atmosphere.
The shrapnel includes mysterious particles called muons which can be seen as faint blue flashes known as Cherenkov radiation in the observatory's dark water. The array of 3,120 beachball-sized globes contain very small sensors that gauge the radiation.
“We can trace these gamma rays back to their source in the sky,” said Cao, dressed in blue scrubs to keep the water clean. “We are able to find something new.”
LHAASO is among dozens of gadgets on Earth and in orbit - suspended in ice tunnels found in Antarctica or interior toaster-sized satellites - trying to comprehend how subject such as for example carbon, oxygen and iron had become.
Located close to the 4,400-meter-tall (14,500-foot-tall) Haizi Mountain, it houses separate instruments that may study different phenomena, incorporating cosmic rays, large energy subatomic contaminants that scientists believe result from the same sources when gamma rays. Cosmic rays are like sparks from an enormous stellar crucible - each consists of flecks of materials from the forging method. Gamma rays are more like light from a glowing hearth. By learning both, the observatory can find out more about what generated them.
The Chinese observatory offers “unprecedented sensitivity,” said Avi Loeb, a Harvard University astrophysicist, that may, for example, help physicists tell whether if some rays result from inside our galaxy or farther away.
It’s not yet complete, however. Cao explained that by the finish of June the instruments will maintain place, including 5,195 electromagnetic detectors, 1,188 muon detectors, and 18 Cherenkov telescopes each how big is a shipping container that may study atmosphere showers in the sky.
“The outcome really justifies the significant effort,” Watson said of the brand new findings. “This is just the end of the iceberg.”
Source: japantoday.com
