New Delhi, Sep 21
In a first, scientists at the Indian Institute of Astrophysics (IIA), an autonomous institute of the Department of Science and Technology (DST), have discovered interaction between a radio jet from a dwarf galaxy and interstellar gas causing shock waves.
The team found that the radio jet emitted from the Active Galactic Nuclei (AGN) -- a black hole -- from the centre of the galaxy NGC 4395. AGN is known to emit bright jets and winds and shape their galaxies.
The bright jet interacted with the surrounding interstellar medium at a small spatial scale of about or about 30 light years. The dwarf galaxy is situated at a distance of about 14 million light years.
In the study, published in a paper in the Astrophysical Journal, the team combined data from radio to X-ray wavebands from the galaxy NGC 4395 to find the interaction around the black hole.
“We decided to investigate how the radio jet from a small black hole interacts with the gas in a dwarf galaxy called NGC 4395,” said lead author Payel Nandi, and doctoral student at IIA.
The team used data from the UltraViolet Imaging Telescope (UVIT) on board AstroSat -- India’s first dedicated space observatory -- launched by ISRO in 2015, as well as Chandra for X-ray data Gemini-North and Hubble Space Telescope for optical data.
The findings showed a unique radio structure resembling a bipolar jet, whose core was centred at the black hole location.