Counting All the Antistars in the Sky
April 20, 2021•
Physics 14, s50
Analyzing gamma-ray sources leads to an upper limit on how many antimatter stars could exist in the Milky Way.
S. Dupourqué/IRAP
×
Nowadays it is taken for granted that the Universe contains no substantial amounts of antimatter. Most cosmological models include hypothetical physical processes to explain why matter dominates although the Universe should have been created with equal amounts of both. But in 2018, the Alpha Magnetic Spectrometer 2 (AMS-02) experiment on the International Space Station possibly detected several antihelium nuclei, suggesting that some original antimatter survived to form antistars and even antigalaxies. Now, Simon Dupourqué and colleagues at the Institut de Recherche en Astrophysique et Planétologie (IRAP), France, identify possible antistars based on ten years of gamma-ray observations from the orbiting Fermi Gamma-ray Space Telescope and derive constraints on how man
Scientists spot jets of energy shooting at speed of light from supermassive black hole
dailystar.co.uk - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from dailystar.co.uk Daily Mail and Mail on Sunday newspapers.
NASA, international astronomers announce unprecedented data on famous supermassive black hole M87
foxnews.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from foxnews.com Daily Mail and Mail on Sunday newspapers.
E-Mail
IMAGE: Gamma-ray image above 10 TeV around SNR G106.3+2.7 as seen by the Tibet ASgamma experiment. PSF shows smearing by the angular resolution. Black/cyan contours represent the SNR shell and the. view more
Credit: Image by IHEP
The Tibet ASgamma experiment, a China-Japan joint research project, has discovered gamma rays beyond 100 TeV (tera electron volts) from G106.3+2.7, a supernova remnant (SNR) 2600 lightyears from Earth.
These gamma rays are of the highest energy ever observed from SNRs, and are probably produced in collisions between cosmic rays (protons) accelerated in G106.3+2.7 and a nearby molecular cloud. SNR G106.3+2.7 is thus the first candidate object with sufficient evidence in the Milky Way that can accelerate cosmic rays (protons) up to 1 PeV (peta electron volts), said HUANG Jing, one of the leading researchers of the study from the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences. It will open an important