Researchers have made a groundbreaking discovery by successfully generating high-density relativistic electron-positron pair plasmas in a lab setting, opening up new avenues for understanding the extreme environments of black holes and neutron stars.
Recreating Cosmic Fireballs
In a world-first, an international team of scientists has developed the technology to perform reproductions on Earth similar to what plasma ‘fireballs’ might look like — enabling research under more controlled conditions than is possible in deep space. One of these plasmas, called a relativistic electron-positron pair plasma as well as one that hangs around black holes and with neutron star that is composed of bunch of electron-positron pairs all moving at very close to speed of light.
Despite this, our understanding so far has largely been based on theory only because the experimental difficulty of producing such pair plasmas in large quantities. Previously, the researchers designed a new experiment that generates two to three orders of magnitude more electron-positron pairs than ever before. The discovery represents a new paradigm for laboratory astrophysics, enabling scientists to directly examine the microphysics of cosmic phenomena such as gamma-ray bursts and blazar jets.
Using Particle Accelerators for Good
The particle accelerators set the record today credit their success to an exciting new research. With a technique made possible by the Super Proton Synchrotron (SPS) accelerator at CERN in Switzerland, the researchers generated quasi-neutral electron-positron pair beams with very large yields.
Here is how the process works: The SPS accelerator sends more than 100 billion protons at a time that carry energy of motion that is 440 times greater than their rest energy. As high-energy protons collide with atoms, they shed their inner quarks and gluons which recombine into a mulitiparticle shower that subsequently decays to form electrons and positrons. This equated to a beam of sufficient particles that it would begin to behave as though it were a real astrophysical plasma.
Furthermore, these pair beams may be tailored by the researchers to have adjusted emittance, creating a probe that can explore plasma processes in size-scaled analogs of astrophysical environments. That breakthrough opens the door to never-before-possible investigations of the basic physics at play in these that-is-the-most-crazy-thing-we-have-ever-seen cosmic realms.
Conclusion
The generation of high-density relativistic electron-positron pair plasmas through the ultra-intense laser-plasma interaction is a major milestone in plasma science and astrophysics. This paves the way to study directly the microphysics of some of the most enigmatic and energetic events in the universe in-situ, such gamma-ray bursts and blazar jets. The discovery of a magnetar in a star-forming galaxy thousands of times as distant is a significant advance towards connecting theory and experiment, to which the new results will contribute very substantially to our knowledge of these cosmic processes.
