A blazar is a particular type of active galactic nucleus (AGN) with a
central supermassive black hole which emits a jet, a flux of highly
energetic particles and radiation moving almost at the velocity of
light, and which is aligned along the observer's line-of-sight. An
international team of researchers has observed the birth of one of these
objects for the first time by combining observations from several
telescopes, among them the William Herschel Telescope (WHT).
As a point of reference, scientists believe all large galaxies have
centrally located massive black holes, but only about one per cent of
these have active nuclei. For example, our Milky Way's massive black
hole is dormant. The emission from an AGN can often exceed that of the
host galaxy, and originates from the central black hole accreting
circumnuclear gas. But not all this gas is accreted onto the black hole;
some gets accelerated and spewed out in the form of narrow, bi-polar
jets.
"Active galaxies which have jets are usually big, old elliptical
galaxies which, according to the models, are formed by the merger of two
or more smaller galaxies, so that we think that these mergers are the
cause of the activation of the jets" says Rubén García-Benito, a
researcher at the Instituto de Astrofísica de Andalucía (IAA-CSIC), who
has participated in the discovery. "A galactic collision is a very
efficient way to make large masses of gas fall to the centre of a
galaxy, which feeds the supermassive black hole and can produce the
emergence of the jet".
Now, astronomers have imaged the formation of a jet from two younger,
spiral-shaped galaxies, in the process of merging. In scientific
terminology these young spiral galaxies containing jets are called
Narrow Line Seyfert 1 gamma ray emitter galaxies (γ-NLSy1).
Each merging galaxy shows a supermassive black hole at its centre. The
more massive of the two shows a very young jet, with an estimated age
less than 15,000 years, whose existence can be attributed to the
interacton between the galaxies, which started at least 500 million
years ago.
"We are seeing the jet face-on" explains Enrique Pérez Jiménez, a
researcher at the IAA-CSIC and a co-author of the study, "so that we
have found the precursor of a blazar. As an analogy we could say that if
a blazar is an adult, a γ-NLSy1 is a child".
Jets are the most powerful astrophysical phenomena in the universe. They can emit more energy into the universe in one second than our sun will produce in its entire lifetime. That energy is in the form of radiation, such as intense radio waves, X-rays, and gamma-rays.
In general blazars are so bright that they occult the galaxies which host them, so that studying their environment is difficult. However the detected jet in this young galaxy is less energetic, which has permitted the study of the gas and the stars of the host galaxy, providing very valuable information to trace the origin of the jet.
The team obtained the image and the spectra using several of the largest ground-based telescopes in the world, such as the GTC and the WHT on La Palma, as well as the optical/infrared Subaru telescope on Hawaii, and NASA's Chandra X-ray satellite observatory. The WHT ISIS observations were obtained as part of a service programme.
More information:
Vaidehi S. Paliya, Enrique Pérez, Rubén García-Benito, Marco Ajello, Francisco Prada, Antxon Alberdi, Hyewon Suh, C. H. Ishwara Chandra, Alberto Domínguez, Stefano Marchesi, Tiziana Di Matteo, Dieter Hartmann, and Marco Chiaberge, 2020, "TXS 2116-077: A Gamma-Ray Emitting Relativistic Jet Hosted in a Galaxy Merger", ApJ, 892, 133. [ ADS ]
Clemson researchers capture first-ever photographic proof of power-packed jet emerging from colliding galaxies, Clemson University press release, 7th April 2020.
La Palma telescopes participate in the discovery of a young blazar produced by the merger of two galaxies, IAC press release, 7 April 2020.
La fusión de dos galaxias genera la versión juvenil de un blázar, uno de los objetos más energéticos conocidos, IAA press release, 7 April 2020.
Jets from a Galaxy Collision, AAS NOVA research highlights, 8 April 2020.
Based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group of Telescopes (ING) in the Spanish Observatorio del Roque de los Muchachos of the Instituto de AstrofÃsica de Canarias (IAC). The ING is funded by the Science and Technology Facilities Council (STFC-UKRI) of the United Kingdom, the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) of the Netherlands, and the IAC in Spain. IAC's contribution to ING is funded by the Spanish Ministry of Science, Innovation and Universities.
Contact:
Javier Méndez (Public Relations Officer)
Jets are the most powerful astrophysical phenomena in the universe. They can emit more energy into the universe in one second than our sun will produce in its entire lifetime. That energy is in the form of radiation, such as intense radio waves, X-rays, and gamma-rays.
In general blazars are so bright that they occult the galaxies which host them, so that studying their environment is difficult. However the detected jet in this young galaxy is less energetic, which has permitted the study of the gas and the stars of the host galaxy, providing very valuable information to trace the origin of the jet.
The team obtained the image and the spectra using several of the largest ground-based telescopes in the world, such as the GTC and the WHT on La Palma, as well as the optical/infrared Subaru telescope on Hawaii, and NASA's Chandra X-ray satellite observatory. The WHT ISIS observations were obtained as part of a service programme.
More information:
Vaidehi S. Paliya, Enrique Pérez, Rubén García-Benito, Marco Ajello, Francisco Prada, Antxon Alberdi, Hyewon Suh, C. H. Ishwara Chandra, Alberto Domínguez, Stefano Marchesi, Tiziana Di Matteo, Dieter Hartmann, and Marco Chiaberge, 2020, "TXS 2116-077: A Gamma-Ray Emitting Relativistic Jet Hosted in a Galaxy Merger", ApJ, 892, 133. [ ADS ]
Clemson researchers capture first-ever photographic proof of power-packed jet emerging from colliding galaxies, Clemson University press release, 7th April 2020.
La Palma telescopes participate in the discovery of a young blazar produced by the merger of two galaxies, IAC press release, 7 April 2020.
La fusión de dos galaxias genera la versión juvenil de un blázar, uno de los objetos más energéticos conocidos, IAA press release, 7 April 2020.
Jets from a Galaxy Collision, AAS NOVA research highlights, 8 April 2020.
Based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group of Telescopes (ING) in the Spanish Observatorio del Roque de los Muchachos of the Instituto de AstrofÃsica de Canarias (IAC). The ING is funded by the Science and Technology Facilities Council (STFC-UKRI) of the United Kingdom, the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) of the Netherlands, and the IAC in Spain. IAC's contribution to ING is funded by the Spanish Ministry of Science, Innovation and Universities.
Contact:
Javier Méndez (Public Relations Officer)
