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James Webb Space Telescope reveals new surprises on galaxy organic molecules near black holes<!-- wp:html --><div></div> <div> <div class="article-gallery lightGallery"> <div> <p> astronomy and astrophysics (2022). DOI: 10.1051/0004-6361/202244806″ width=”800″ height=”529″/></p> <p> Maps of the central ∼6″ region of NGC 7469, including the AGN and the surrounding star-forming ring. Top left panel: In color and outline in black is the JWST/F770W PSF subtracted image (which mainly follows the 7.7m PAH band). Black regions (s1, s2, s3, s4, s5, s6, and s7) correspond to selected circumnuclear zones of NGC 7469. Red and blue regions (o1, o2, o3, o4, o5, and o6) are in the outflow region. The green line shows the orientation of the nuclear molecular gas bar. The gray lines correspond to the estimated outflow area according to the [S IV]λ10.51 m speed map (see Appendix B). The white box represents the JWST/MRS ch1 FoV (3.2″ × 3.7″), which is practically identical to the Spitzer/IRS angular resolution. The brown star roughly corresponds to the location of the radio supernova SN 2000ft (Colina et al. 2001). Top right panel: JWST/MRS 6.2 m PAH band map derived using a local continuum (see text). Bottom left panel: [Ar II]λ6.99 m emission card. Bottom right panel: 113/6.2 m PAH ratio with local continua (see text). In black are the 6.2 m PAH tire contours. The central region corresponds to this PAH ratio in the nuclear spectrum. All images are displayed on a linear color scale. North is up and east is left, and offsets are measured from the AGN. Credit: Astronomy and Astrophysics (2022). DOI: 10.1051/0004-6361/202244806 </p> </div> </div> <p>Research led by the University of Oxford is the first of its kind to study tiny dust molecules in the nuclear region of active galaxies using early observations from the James Webb Space Telescope (JWST). The study is the first UK-led paper to use spectroscopic data from the JWST Mid-Infrared Instrument (MIRI) and addresses one of the greatest challenges in modern astrophysics: understanding how galaxies form and evolve.</p> <p> <!-- /4988204/Phys_Story_InText_Box --></p> <p>Small matter molecules known as polycyclic aromatic hydrocarbons (PAHs) are among the most abundant organic molecules in the universe and are important astronomical tools. For example, they are considered fundamental building blocks of prebiotic compounds, which may have played a key role in the origin of life. PAH molecules produce extremely bright emission bands in the infrared region when illuminated by stars, allowing astronomers not only to monitor the activity of star formation, but also to use them as sensitive barometers of local physical conditions.</p> <p>This new analysis, led by Dr. Ismael García-Bernete of the University of Oxford’s Department of Physics used JWST’s advanced instruments to characterize, for the first time, the PAH properties in the nuclear region of three luminescent active galaxies. The study was based on spectroscopic data from the JWST’s MIRI, which specifically measures light in the wavelength range of 5–28 microns. The researchers then compared the observations with theoretical predictions for these molecules.</p> <p>Surprisingly, the results surpassed those of previous studies that predicted that PAH molecules would be destroyed near the black hole at the center of an active galaxy. Instead, the analysis revealed that PAH molecules can actually survive in this region, even where highly energetic photons could potentially tear them apart. One possible reason could be that the molecules are protected by large amounts of molecular gas in the nuclear region.</p> <p>But even where PAH molecules survived, the results showed that the supermassive black holes at the heart of galaxies had a significant impact on their properties. In particular, the proportion of larger and neutral molecules increased, indicating that more fragile small and charged PAH molecules may have been destroyed. This places serious limitations on using these PAH molecules to study how quickly an active galaxy is making new stars.</p> <p>“This research is of great interest to the wider astronomy community, especially those focusing on the formation of planets and stars in the most distant and faint galaxies,” said Dr. Garcia-Bernete. “It’s incredible to think that we can observe PAH molecules in the nuclear region of a galaxy and the next step is to analyze a larger number of active galaxies with different properties. This will allow us to better understand how PAH molecules survive and what are their specific properties in the nuclear field Such knowledge is key to using PAHs as an accurate tool for characterizing the amount of star formation in galaxies, and thus how galaxies evolve over time .”</p> <p>The study is published in Astronomy and Astrophysics.</p> <div class="article-main__explore my-4 d-print-none"> <p> New image from Webb shows galaxy NGC 1365, known to have an actively feeding supermassive black hole </p> </div> <div class="article-main__more p-4"> <strong>More information:</strong><br /> I. García-Bernete et al, A high angular resolution view of PAH emission in Seyfert galaxies using JWST/MRS data, Astronomy and Astrophysics (2022). <a target="_blank" href="https://dx.doi.org/10.1051/0004-6361/202244806" rel="noopener">DOI: 10.1051/0004-6361/202244806</a></div> <div class="d-inline-block text-medium my-4"> <p> Provided by the University of Oxford<br /> <a target="_blank" class="icon_open" href="http://www.ox.ac.uk/" rel="noopener"></a></p> </div> <p> <!-- print only --></p> <div class="d-none d-print-block"> <p> <strong>Quote</strong>: James Webb Space Telescope reveals new surprises about organic molecules from galaxies near black holes (2022, October 11) retrieved October 11, 2022 from https://phys.org/news/2022-10-james-webb-space -telescope-reveals. html </p> <p> This document is copyrighted. Other than fair dealing for personal study or research, nothing may be reproduced without written permission. The content is provided for informational purposes only. </p> </div> </div><!-- /wp:html -->

astronomy and astrophysics (2022). DOI: 10.1051/0004-6361/202244806″ width=”800″ height=”529″/>

Maps of the central ∼6″ region of NGC 7469, including the AGN and the surrounding star-forming ring. Top left panel: In color and outline in black is the JWST/F770W PSF subtracted image (which mainly follows the 7.7m PAH band). Black regions (s1, s2, s3, s4, s5, s6, and s7) correspond to selected circumnuclear zones of NGC 7469. Red and blue regions (o1, o2, o3, o4, o5, and o6) are in the outflow region. The green line shows the orientation of the nuclear molecular gas bar. The gray lines correspond to the estimated outflow area according to the [S IV]λ10.51 m speed map (see Appendix B). The white box represents the JWST/MRS ch1 FoV (3.2″ × 3.7″), which is practically identical to the Spitzer/IRS angular resolution. The brown star roughly corresponds to the location of the radio supernova SN 2000ft (Colina et al. 2001). Top right panel: JWST/MRS 6.2 m PAH band map derived using a local continuum (see text). Bottom left panel: [Ar II]λ6.99 m emission card. Bottom right panel: 113/6.2 m PAH ratio with local continua (see text). In black are the 6.2 m PAH tire contours. The central region corresponds to this PAH ratio in the nuclear spectrum. All images are displayed on a linear color scale. North is up and east is left, and offsets are measured from the AGN. Credit: Astronomy and Astrophysics (2022). DOI: 10.1051/0004-6361/202244806

Research led by the University of Oxford is the first of its kind to study tiny dust molecules in the nuclear region of active galaxies using early observations from the James Webb Space Telescope (JWST). The study is the first UK-led paper to use spectroscopic data from the JWST Mid-Infrared Instrument (MIRI) and addresses one of the greatest challenges in modern astrophysics: understanding how galaxies form and evolve.

Small matter molecules known as polycyclic aromatic hydrocarbons (PAHs) are among the most abundant organic molecules in the universe and are important astronomical tools. For example, they are considered fundamental building blocks of prebiotic compounds, which may have played a key role in the origin of life. PAH molecules produce extremely bright emission bands in the infrared region when illuminated by stars, allowing astronomers not only to monitor the activity of star formation, but also to use them as sensitive barometers of local physical conditions.

This new analysis, led by Dr. Ismael García-Bernete of the University of Oxford’s Department of Physics used JWST’s advanced instruments to characterize, for the first time, the PAH properties in the nuclear region of three luminescent active galaxies. The study was based on spectroscopic data from the JWST’s MIRI, which specifically measures light in the wavelength range of 5–28 microns. The researchers then compared the observations with theoretical predictions for these molecules.

Surprisingly, the results surpassed those of previous studies that predicted that PAH molecules would be destroyed near the black hole at the center of an active galaxy. Instead, the analysis revealed that PAH molecules can actually survive in this region, even where highly energetic photons could potentially tear them apart. One possible reason could be that the molecules are protected by large amounts of molecular gas in the nuclear region.

But even where PAH molecules survived, the results showed that the supermassive black holes at the heart of galaxies had a significant impact on their properties. In particular, the proportion of larger and neutral molecules increased, indicating that more fragile small and charged PAH molecules may have been destroyed. This places serious limitations on using these PAH molecules to study how quickly an active galaxy is making new stars.

“This research is of great interest to the wider astronomy community, especially those focusing on the formation of planets and stars in the most distant and faint galaxies,” said Dr. Garcia-Bernete. “It’s incredible to think that we can observe PAH molecules in the nuclear region of a galaxy and the next step is to analyze a larger number of active galaxies with different properties. This will allow us to better understand how PAH molecules survive and what are their specific properties in the nuclear field Such knowledge is key to using PAHs as an accurate tool for characterizing the amount of star formation in galaxies, and thus how galaxies evolve over time .”

The study is published in Astronomy and Astrophysics.

New image from Webb shows galaxy NGC 1365, known to have an actively feeding supermassive black hole

More information:
I. García-Bernete et al, A high angular resolution view of PAH emission in Seyfert galaxies using JWST/MRS data, Astronomy and Astrophysics (2022). DOI: 10.1051/0004-6361/202244806

Provided by the University of Oxford

Quote: James Webb Space Telescope reveals new surprises about organic molecules from galaxies near black holes (2022, October 11) retrieved October 11, 2022 from https://phys.org/news/2022-10-james-webb-space -telescope-reveals. html

This document is copyrighted. Other than fair dealing for personal study or research, nothing may be reproduced without written permission. The content is provided for informational purposes only.

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