Madrid, 23 years (European Press)
Researchers at the Princeton Plasma Physics Laboratory (PPPL) and the SLAC National Accelerator Laboratory have accessed the formation of these fast radio bursts – which release as much energy as the sun emits in one second of the year – in a way that was once thought impossible. with today’s technology.
Celestial bodies that produce unusual explosions in space, such as collapses or neutron stars, called magnetars (magnet + star) are trapped in a strong magnetic field. These fields are so strong that they turn vacuum into a strange plasma composed of matter and antimatter in the form of pairs of negatively charged electrons and positively charged positrons, according to the theory of quantum electrodynamics (QED). Emissions from this pair are thought to be responsible for the powerful fast radio burst (FRB).
Matter and antimatter plasma, called “even plasma,” contrasts with ordinary plasma which triggers fusion reactions and makes up 99% of the visible universe. This plasma only consists of matter in the form of electrons and atomic nuclei or ions whose mass is much larger. Plasma electrons and positrons are composed of particles of equal mass but opposite charge that are subject to both annihilation and creation. Such plasmas can exhibit very different collective behavior.
Compact analogue of magnetic environment
“Our lab simulations are small-scale analogues of the magnetic environment,” said physicist Kenan Ku of the Princeton Department of Astrophysics in a statement. “This allowed us to analyze the plasma from the QED pair,” Coe, first author of the study presented in Plasma Physics and also the first author of an expanded research paper in Physical Review Letters, said in a statement.
“Instead of simulating a strong magnetic field, we used a powerful laser,” Zhou said. “It converts energy into paired plasma via the so-called QED cascade. Then the plasma pair converts the laser pulse to a higher frequency,” he said. “The exciting results demonstrate the prospects for fabricating and monitoring QED pair plasmas in the laboratory and allow experiments to verify theories about fast radio bursts.”
Previously, the pair producing plasma had been created in the laboratory, physicist Nat Fish, professor of astrophysics at Princeton University and associate director of academic affairs at PPPL, who served as lead investigator for the study, said. “We think we know the laws that govern their collective behavior,” Fish said. “But until we actually produce a plasma pair in the lab that demonstrates a mass phenomenon that we can test, we can’t be completely sure of that.”
“The problem is that collective behavior in plasma pairs is difficult to observe,” he added. “So a big step for us was to think of this as a co-production and monitoring issue, realizing that great monitoring methods ease the conditions on what needs to be produced, and thus bring us to a facility that is more user-friendly. ”
The unique simulation proposed by the article creates a high-density QED plasma pair by striking a laser with a dense electron beam traveling close to the speed of light. This approach is cost-effective compared to the commonly proposed method for ultra-powerful laser collisions to generate QED chains. Focusing also slows the movement of plasma particles, allowing for a stronger collective effect.
“No laser is powerful enough to achieve this today and it could cost billions of dollars to build it,” Chu said. “Our approach strongly supports the use of electron beam accelerators and lasers that are sufficiently powerful to achieve paired QED plasmas. The implication of our research is that supporting this approach can save a lot of money.”
Preparations are now underway to test the simulation with a new round of laser and electron experiments at SLAC. “In a sense, what we’re doing here is a starting point for the circuit that produces radio bursts,” said Sebastian Morin, the SLAC researcher and former postdoctoral fellow at Princeton University, who co-authored two papers with Qu. And fish.
“If we could observe something like a radio burst in the lab, that would be very interesting,” said Morin. “But the first part is just to look at the scattering of the electron beam, and once we do that, we’ll increase the laser intensity to reach higher densities to look at electron-positron pairs. The idea is that our experiment will expand over the next two years or so.”
The overall goal of the study, Zhou said, was to understand how objects such as magnetars form plasma pairs and what new physics is associated with FRBs. “These are basic questions that concern us.”
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