Scientists trace high-energy ghost particles to a ‘Shadow Blaster’ galaxy.

Astronomers have been able to trace a high-energy ‘ghost particle’ back to the Shadow Blaster, a star-forming galaxy located 11 billion light-years away. This means that this particle, the neutrino, has been traveling to us since the universe was 13.8 billion years old, and it is about 3 billion years old.
This discovery provides the first evidence of star formation Galaxies Like the Shadow Blaster, he plays an important role in filling the universe with mysterious, high-energy cosmic ghosts.Neutrinos. These particles get their scary nickname because they have no mass or electrical charge, they pass through matter with little interaction while moving at almost no speed. Speed of light. To illustrate, when you read the previous sentence, more than 65 billion neutrinos stream through every square inch of your body; That’s about 100 billion per square centimeter.
Despite the difficulty associated with detecting such particles, humanity has been able to detect neutrinos since the 1960s, but only a few sources of these particles have been identified. Neutrinos are the second most abundant particles in the universe after photons, particles of light, and specific sources are not close enough to explain this abundance. This has prompted a search for other hidden neutrino sources, especially those that can accelerate neutrinos to high energies. Now, this research has led to the identification of the incredibly bright Shadow Blaster galaxy, officially designated JCMT0402−0424, which luminesces in the infrared, as a possible source of the neutrino.
“Shadow Blaster has the kind of dense, gas-rich environment that theoretical models have long suggested could efficiently produce high-energy neutrinos,” said Yuji Urata of MITOS Science Co., LTD. In Taiwan He said in a statement. “If confirmed, Shadow Blaster would be the first single star-forming dust galaxy ever directly associated with a high-energy neutrino event.”
So far, there are no other reliable candidates as potential sources for this high-energy neutrino, named IC 210922A.
Chasing ghosts
Astronomers were alerted to the existence of IC 210922A half a decade ago when this high-energy neutrino event was detected by the IceCube Neutrino Observatory located in Antarctica. This led the astronomical community to scan space in the direction of the Eridanus constellation for possible sources of an electromagnetic counterpart to this event using an array of telescopes. This did not show any convincing gamma-ray,
Urata and his colleagues began their personal search using the James Clerk Maxwell Telescope (JCMT), operated by the East Asian Observatory, and the Submillimeter Array (SMA), and discovered the Shadow Blaster, a galaxy in the right location and at the right brightness level associated with galaxy IC 210922A. The team followed this up with an investigation using the Atacama large millimeter/submillimeter array (Alma), an array of 66 radio antennas in northern Chile.
The discovery of this galaxy was possible because it is affected by the force of gravity. Gravitational lens It is a phenomenon that occurs when a large-mass object comes between Earth and a distant background source, bending the fabric of space-time. When light from a background source travels along this bend, its path is curved. This results in light from the lensed source arriving at different times into our telescopes, amplifying it.
In the case of the Shadow Blaster, before the team could learn anything about this distant galaxy, they had to find out more about the object that acts as the medium’s gravitational lens, specifically the type of object, its mass, and its distance from us. To do this, they turned to the Gemini North telescope, the Gemini Multi-Object Spectrometer (GMOS) and the Gemini Near-Infrared Spectrometer (GNIRS) instruments.
With the gravitational lensing model identified, the team discovered that the Shadow Blaster is a galaxy with an extremely compact core filled with dense clouds of gas and dust that fuel an intense explosion of star formation. A region like this has long been viewed as a powerful particle accelerator. Because the Shadow Blaster lacks a supermassive black hole, this research shows that these regions can still act as cosmic particle accelerators when they harbor dormant black holes and in the absence of powerful jets erupting from active galactic nuclei (AGNs).
As for the total number of neutrinos, this research can help explain that as well. Dense star-forming galaxies, or starburst galaxies, are thought to have been prevalent about 10 billion years ago in the early universe. Thus, these galaxies may have produced a large number of high-energy neutrinos. However, proving this may be difficult, because astronomers don’t have the good fortune to find all of these galaxies lurking behind a gravitational lens, which means they may be too faint and distant to study.
“Our analysis suggests that this population could contribute up to approximately 20% of the observed diffuse neutrino background measured by IceCube,” concluded Urata.
The team’s research was published Wednesday (June 17) in the journal Nature astronomy.




