active galactic nuclei tagged posts

AI helps Distinguish Dark Matter from Cosmic Noise

An AI-powered tool can distinguish dark matter’s elusive effects from other cosmic phenomena, which could bring us closer to unlocking the secrets of dark matter.

Dark matter is the invisible force holding the universe together – or so we think. It makes up around 85% of all matter and around 27% of the universe’s contents, but since we can’t see it directly, we have to study its gravitational effects on galaxies and other cosmic structures. Despite decades of research, the true nature of dark matter remains one of science’s most elusive questions.

According to a leading theory, dark matter might be a type of particle that barely interacts with anything else, except through gravity...

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Investigating the Contribution of Gamma-Ray Blazar Flares to Neutrino Flux

Fermi spots a record flare from blazar.
Caption: A new study suggests that high-energy neutrinos of blazars might be produced mainly during the gamma-ray flare phase.
Credit: NASA Goddard Space Flight Center from flickr (https://www.flickr.com/photos/24662369@N07/19578977022)
License type: CC BY 2.0

Gamma-ray flares from blazars can be accompanied by high-energy neutrino emission. To better understand this phenomenon, an international research team has statistically analyzed 145 bright blazars. They constructed weekly binned light curves and utilized a Bayesian algorithm, finding that their sample was dominated by blazars with low flare duty cycles and energy fractions. The study suggests that high-energy neutrinos of blazars might be produced mainly during the flare phase.

Blazars ...

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Scientists find Pair of Black Holes Dining Together in Nearby Galaxy Merger

Credit: ALMA (ESO/NAOJ/NRAO); M. Weiss (NRAO/AUI/NSF)

While studying a nearby pair of merging galaxies using the Atacama Large Millimeter/submillimeter Array (ALMA) – an international observatory co-operated by the U.S. National Science Foundation’s National Radio Astronomy Observatory (NRAO) – scientists discovered two supermassive black holes growing simultaneously near the center of the newly coalescing galaxy. These super-hungry giants are the closest together that scientists have ever observed in multiple wavelengths. What’s more, the new research reveals that binary black holes and the galaxy mergers that create them may be surprisingly commonplace in the Universe...

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Space study offers Clearest Understanding yet of the Lifecycle of Supermassive Black Holes

A supermassive black hole
Supermassive black holes can be obscured by a doughnut-shaped ring of dust and gas, known as a “torus.” (Photo by ESA/NASA, the AVO project and Paolo Padovani)

Black holes with varying light signatures but that were thought to be the same objects being viewed from different angles are actually in different stages of the life cycle, according to a study led by Dartmouth researchers.

The research on black holes known as “active galactic nuclei,” or AGNs, says that it definitively shows the need to revise the widely used “unified model of AGN” that characterizes supermassive black holes as all having the same properties.

The study, published in The Astrophysical Journal Supplement Series, provides answers to a nagging space mystery and should allow researchers to create more pre...

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