[ad_1]
More than 400 light years from Earth, there is a cluster of young neutron stars that are too hot for their age. These stars, known as the “Magnificent Seven”, emit an ultra-high energy X-ray flux that scientists have not been able to explain.
Now, scientists have proposed a possible culprit: axions, theoretical particles that turn into light particles when they are in the presence of a magnetic field.
In a new study, published Jan.12 in the journal Physical examination letters, Benjamin Safdi, physicist at the Lawrence Berkeley National Laboratory, and his colleagues used supercomputers to model the idea that axions produced inside stars could convert to X-rays in magnetic fields outside the stars. Axions have never been observed directly, but they were first theorized in the 1970s. It is too early to say for sure whether axions exist or are the real culprit behind weird x-rays, has Safdi said, but the researchers hope the new computer modeling may point to something outside of the Standard Model of physics, which describes known subatomics. particles.
Related: The 11 biggest unanswered questions about dark matter
“We are quite confident that [X-ray] excess exists and very confident that there is something new in this excess ”, Safdi said in a press release. “If we were 100% sure that what we are seeing is a new particle, it would be huge. It would be revolutionary in physics.”
Mysterious X-rays
Considering their age and type, the Magnificent Seven should only emit low energy x-rays and ultraviolet light. But astronomers have observed something they can’t explain: high-energy x-rays coming out of stars. Neutron stars are the remnants of giant stars that have run out of fuel and collapsed; a type of neutron star, called pulsar, emits emissions across the entire electromagnetic spectrum, including high-energy X-rays. But the Magnificent Seven are not pulsars.
Scientists also searched behind the neutron star cluster for other objects that could emit the mysterious x-rays, but neither the European Space Agency’s XMM-Newton telescope nor NASA’s Chandra x-ray telescope does ‘found anything that could be the culprit.
Axions have also been proposed as a solution to the mystery. But could axions really be produced inside a neutron star? To find out, Safdi and his colleagues turned to supercomputers at the University of Michigan and Lawrence Berkeley National Laboratory.
“There’s a lot of data processing and analysis that went into all of this,” Safdi said. “You have to model the interior of a neutron star in order to predict how many axions should be produced inside that star.”
Elusive Axions
An axion, if it exists, is a elementary particle with a very low mass. Axions could be a component of dark matter, the unobserved substance that appears to make up more than a quarter of the mass of the universe, based on its gravitational effects.
Safdi and his team discovered that axions could work neutrinos, another extremely light subatomic particle that has been demonstrated. Neutrinos are produced inside neutron stars when neutrons collide with each other; axions could be produced in the same way.
Given their low mass and low interactions with other matter, axions could easily escape from the nuclei of neutron stars and head into space. Extremely strong magnetic fields surround neutron stars. In the presence of these fields, the axions would convert into photons, or light particles. Traveling at wavelengths shorter than visible light, these light particles would be recorded as high-energy x-rays on astronomical instrumentation.
“We are not claiming that we have made the discovery of the axion yet, but we are saying that the additional X photons can be explained by the axions,” Raymond Co, postdoctoral researcher at the University of Minnesota who collaborated on the study, said in the statement. “This is an exciting discovery of the excess of X photons, and it’s an exciting possibility that is already consistent with our interpretation of axions.”
The next step, Safdi said, is to look for axions in white dwarfs, another set of stars that shouldn’t emit x-rays.
“It starts to be pretty convincing that it’s something beyond the standard model if we see excess x-rays there as well,” he says.
Originally posted on Live Science.
[ad_2]
Source link