Using ALMA, astronomers uncovered “Shadow Blaster” – a compact, dust-obscured starburst galaxy located within the localization region of the IceCube neutrino event IC 210922A. Thanks to gravitational lensing, researchers revealed an intense, gas-rich core where extreme star formation could generate the conditions needed to produce high-energy neutrinos.
While the association is not yet confirmed, the discovery highlights the power of multi-messenger astronomy and suggests that compact starburst galaxies may contribute to the cosmic neutrino background. Read the full ALMA press release here and te full article here (DOI).
Image shows a close-up of the gravitationally lensed galaxy nicknamed “Shadow Blaster,” which astronomers have identified as the likely source of the high-energy neutrino event IC 210922A, detected by the IceCube Neutrino Observatory in 2021.
Gravitational lensing occurs when a very massive foreground galaxy bends spacetime, acting as a cosmic magnifying glass that enlarges and distorts the image of a more distant galaxy behind it. In this case, a foreground galaxy, which is not visible in this image, is bending the light of the more distant Shadow Blaster galaxy, creating multiple distorted images of it that appear here as yellow arcs. Credit: NOIRLab/NSF/AURA/ALMA (ESO/NAOJ/NRAO)