A significant discovery by Valeria Olivares, a physicist at the University of Santiago, and an international team of astronomers, published in Nature Astronomy, reveals a correlation between the surface brightness of hot and warm gas in the central filaments of galaxy clusters.
This finding provides crucial insight into the origin of these gaseous filaments, the primary fuel source for supermassive black holes and star formation.
Intriguingly, this newly discovered correlation mirrors the patterns seen in the tails of jellyfish galaxies, suggesting an unexpected link between these cosmic structures.
Dr. Olivares observed this relationship in multiple galaxy cluster centers, regions containing the universe’s largest galaxies and colossal black holes with masses ranging from millions to tens of billions of suns.
This research confirms theoretical models where supermassive black hole jet eruptions, releasing significant energy and turbulence, interact with surrounding hot plasma to form filaments. These filaments contain both hot ionized and cooler gas, with the cooler gas falling to the galactic center and feeding the black hole. The resulting jet energy release is key to understanding the evolution and properties of these filaments.
An international team of optical and X-ray observation specialists from Australia, Canada, the United States, and Italy collaborated on this research. According to Dr. Olivares, "This underscores the value of observations across various wavelengths and strong communication among diverse scientific disciplines."
While a previous relationship between hot gas (observed in X-rays) and warm gas had been noted in some galaxy clusters, X-ray filaments had not been isolated until this research. This discovery enabled the Paris Observatory PhD in Astrophysics to quantify and confirm a strong correlation between these two gas phases. The breakthrough was achieved through an innovative technique that isolated the filaments at X-ray wavelengths using observations from the Chandra space telescope, leading to the discovery of this correlation.
The research benefited from the high spatial resolution and sensitivity provided by the Very Large Telescope (VLT), situated on Cerro Paranal in northern Chile. Its innovative MUSE (Multi Unit Spectroscopic Explorer) instrument allows for the creation of detailed 3D views of the Universe, making this work possible.
The tool uses 24 spectrographs to separate light into its constituent colors to create both images and spectra of selected regions of the sky.
“We were able to identify fainter filaments and observe a wider range of these structures, thereby establishing a correlation between hot gas and warm gas,” said the NASA NPP fellow researcher.
Access the article An Hα–X-ray surface-brightness correlation for filaments in cooling-flow clusters