Active Galactic Nucleus (AGN)

Active Galactic Nuclei (AGNs) Latest News

Astronomers from the Russian Academy of Sciences, using the Spektr-RG (SRG) space observatory, have detected 11 new Active Galactic Nuclei (AGNs) during their all-sky X-ray surveys.

What are Active Galactic Nuclei (AGNs)?

• Active Galactic Nuclei (AGNs) are compact regions at the centers of galaxies that emit exceptionally high levels of electromagnetic radiation, often outshining the rest of the galaxy.
• This intense emission arises from either accretion of matter by a supermassive black hole or intense star formation activity.
• AGNs are among the most luminous and persistent energy sources in the universe and are critical to understanding galaxy formation and evolution.
• The newly detected AGNs were identified during an optical and X-ray inspection of sources listed in the ARTSS1-5 catalog, using SRG’s ART-XC telescope.
• The team has also previously identified more than 50 AGNs and several cataclysmic variable stars.

Key Characteristics of the 11 Newly Detected AGNs

• All 11 AGNs are located at redshifts ranging from 0.028 to 0.258, indicating they are relatively nearby in cosmic terms.
• Their X-ray luminosities fall within the typical range of 2 to 300 × 10³⁹ erg/s, which is consistent with known AGN profiles.

Classification into Seyfert Types

• All detected AGNs were classified as Seyfert galaxies, a type of AGN that is common and well-studied:
  • 7 galaxies were classified as Seyfert Type 1 (Sy 1), characterized by broad optical emission lines.
  • 3 galaxies were classified as Seyfert Type 1.9 (Sy 1.9), showing partially broadened lines.
  • 1 galaxy was classified as Seyfert Type 2 (Sy 2), which exhibits narrow emission lines only.
• Seyfert galaxies appear like normal galaxies in visible light but show strong infrared and X-ray emissions due to activity at their cores.

Active Galactic Nuclei (AGNs) FAQs

Q1: What are Active Galactic Nuclei (AGNs)?
Ans: AGNs are extremely bright central regions of some galaxies, powered by supermassive black holes accreting matter.

Q2: Why are AGNs important in astrophysics?
Ans: AGNs help scientists understand galaxy evolution, black hole activity, and cosmic energy sources across the universe.

Q3: What types of AGNs are there?
Ans: Common types include quasars, blazars, Seyfert galaxies, and radio galaxies, each emitting energy across various wavelengths.

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Source: PHY