Events Calendar
Compact Symmetric Objects and the Evolution of Active Galaxies
Thursday August 19, 2021
2:00 pm
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Presenter: | Evan Sheldahl (UNM) |
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Series: | Center for Astrophysics Research and Technologies Seminar Series | |
Abstract: |
Active galactic nuclei (AGN) are incredibly energetic systems consisting of matter accreting around a supermassive black hole, thought to exist at the centers of most galaxies. They emit radiation across the electromagnetic spectrum and can vary greatly in size. Compact symmetric objects (CSOs) are a class of radio AGN, so called because they are less than 1 kpc in size and symmetrical around their central core. Based on multi-epoch observations, we know they typically have ages of around 20-3000 years. Their compact nature may be due to them representing an early stage in the evolution of radio galaxies, being confined by a dense interstellar medium, or living only for a short period of time. Other than that, their defining traits have not been well established, leading to some ambiguity and incorrect identifications. Previous observations have determined that CSOs are heavily involved in the dynamics of the interstellar medium of their host galaxies and can be a major driver of AGN feedback. This makes them very interesting to study in the context of galaxy evolution. To precisely determine what counts as a CSO, my research involves the calibration, imaging, and polarimetric analysis of multi-frequency observations of over two hundred CSO candidates, observed by the Very Large Array (VLA). As an additional objective, since CSOs are typically unpolarized, I am extracting data about these CSO candidates to assess their viability as VLA phase and polarization calibrators. Those determined suitable enough will be added to the VLA calibrator manual.
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Host: | Gregory Taylor | |
Location: | PAIS-3300, PAIS | |