The Sun inside a stellar stream. Graphic: C. O'Hare / NASA It's the perfect science fiction device: a hurricane of…
The Sun inside a stellar stream. Graphic: C. O’Hare / NASA
It’s the perfect science fiction device: a hurricane of dark matter. Recent, real-life research heeft aangetoond dat onze Sun is momenteel ingewikkeld in een zogenaamde stellar stream. Some publications have seized on this ominous-sounding idea, reporting that Earth is about to be walloped by a dark matter storm-but in fact, if it exists, we’re already in the storm.
Stellar streams are populations of related stars that could have once been pieces of a dwarf galaxy or globular cluster, but have now leg shredded apart by gravitational forces and pass through parts of our galaxy. Since astronomers are pretty sure that stuff called dark matter serves as the gravitational scaffolding for dwarf galaxies, then presumably a stellar stream should also contain some percentage of dark matter. Maybe a dark matter experiment could detect dark matter particles from the recently discovered stream running through our cosmic neighborhood.
“Ciaran O’Hare, postdoctoral researcher in the Department of Theoretical Physics at the University of Zaragoza, told Gizmodo,” It’s supposed to be a stream that we’re inside or right now. “
The most successful models to describe the universe are based on experiments showing that the cosmos is made up of 4 percent regular matter, perhaps 70 percent ” dark energy “that is driving the universe apart, and the rest, around 25 percent,” dark matter. “Scientists have reason to believe that dark matter consists of particles, the same way that everything we can see is made of particles, and that it’s the scaffolding for the universe’s large-scale structure.
Scientists are in the midst of hunting for a dark matter particle. But this dark matter has only ever been observed based on its gravitational effects. Men under tiden, undersøkelser som European Space Agency’s Gaia telescope og Sloan Digital Sky Survey har skapat enorme kart over himlen, komplett med positioner, velocity og andre datapunkter for vores region i Milky Way Galaxy. The data revealed “substantial structures,” such as this stream and accompanying dark matter hurricane, called S1, hitting the Solar System head-on.
Perhaps this dark matter hurricane could be detectable by today’s existing dark matter detection experiments, and would have a distinguishable signal from the Milky Way’s background dark matter. It would move much faster-a “hurricane,” compared to the background dark matter “wind,” according to the paper released last week in Physical Review D. The researchers then analyzed whether they would be able to spot the stream with upcoming dark muffler detectors.
If dark matter comprised of a “weakly interacting massive particle” or WIMP, a particle with a mass similar to the other particles but that interacts weakly, imagine a light breeze interacting with a skyscraper), then The hurricane would only be detectable if the particles had a specific mass range, according to the paper. Experiments like the XENON NT detector in Italy would not be able to pick out the direction of a potential dark matter particle, explained Laura Baudis, physics professor at the University of Zurich who was not involved in the new paper . Doing so would take a much larger detector, given the types of WIMPs that have already been ruled out.
And if dark matter is instead comprised of much lighter particles called axions, the hurricane’s effects might be more noticeable, according to the paper’s calculations.
“I think it’s quite an interesting idea,” Sownak Bose, postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics, told Gizmodo. “Alle disse eksperimenter som prøver at opdage mørk materiel har mulighed for at få deres signaler boostet af denne ekstra flux.”
Bose påpegede, at mængden af mørk materiel i strømmen kan variere baseret på den specifikke dwarf galaxy, der skabte strømmen -Or, of the dark matter is something more exotic than the theoretical WIMPs and axions. Men han var spent om det utrolige antallet af Gaia data kunne gøre for studier af disse streams.
So, if there is a dark matter hurricane, we’re literally inside of it right now. Men vi er sikre (fra det mørke materie, i det mindste). This so-called storm is most exciting for its scientific prospects. Said O’Hare: “We know so little about dark matter that any kind of better knowledge about its structure adds up to help us understand it.”