Online Colloquium
Friday, 8 April 2022, at 01.15 p.m (UT+7)

Optically Dull Active Galactic Nuclei in COSMOS Field

Itsna Khoirul Fitriana, Ph. D., Postdoctoral at Tohoku University

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Meeting ID: 918 4272 5606
Passcode: AstroITB

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In this talk, Fitriana, Ph. D. will discuss about their recent work on the optically dull (OD) active galactic nuclei (AGN). These objects are fascinating since their X-ray emission is bright even though the AGN signature in the optical regime is absent. By studying 180 OD AGNs from the COSMOS field data, they found that the bright host galaxy dilution explains nearly 70% of our OD AGN sample. By estimating the Eddington ratio, they also found that ~50% of their OD AGNs have lower accretion rate of (λEdd) ≲ 10-2 than the typical AGN value.