I Simposio de Postgrado 2023. Ingeniería, ciencias e innovación

I SIMPOSIO 2023 A SYSTEMATIC SEARCH FOR SUPERMASSIVE BLACK HOLE BINARY CANDIDATES USING THE ZWICKY TRANSIENT FACILITY DATA ABSTRACT We are using the optical aperture ZTF photometric light curves to conduct a search for supermassive black hole binary (SMBHB) candidates froma sample of 1528 Seyfert galaxies (Rakshit et al. 2017). SMBHB can be identified by detecting periodic signals in their lightcurve.However,thePSDofAGN,whichrisestowards longer time-scales (also known as ‘red-noise’) can produce peaks that will look significant when not modeled appropriately. For our search, we use a Bayesian model-selection and parameter- estimation framework (Witt et al. 2022), which searches for periodic signals in data characterized by ‘red-noise’ PSDs in the AGN light curves. We generated simulated quasar light curves with DRW variability, incorporating a realistic distribution of σ and , along with binary light curves that featured sinusoidal variability on top of a DRW process, encompassing a wide range of periods and amplitudes. We utilized a Bayesian nested-sampling analysis to examine the likelihoods of the corresponding models and determined the preferred model based on the BIC to select binary candidates. However, light curves with high sampling rates obtained from the Kepler Mission (Borucki et al. 2010) have raised concerns regarding DRWmodel to accurately describe AGN variability due to the steeper slopes observed in the PSDs at higher frequencies (Mushotzky et al. 2011). To avoid this discrepancy, Kelly et al. (2014) and Kasliwal et al. (2017), Moreno et al. (2019) conducted a thorough investigation of the CARMA(2,1) model or damped harmonic oscillator (DHO) model and established a framework for modeling AGN light curves as DHOs.We used a Python package called EzTao (Yu et al. 2022),which includes themapping fromtheCARMAparameterization to the celerite parameterization. Thus, in addition to Bayesian model-selection, we also use the CARMA(2,1) model to confirm the SMBHB candidates. 1 Departamento de Astronomía, Universidad de Chile. 2 Department of Physics and Astronomy, West Virginia University. 3 Department of Physics and Astronomy, Vanderbilt University. 4Instituto de Física y Astronomía, Universidad de Valparaíso. *Email: priya@das.uchile.cl Priyanjali Patel 1* , Paulina Lira 1 , Caitlin A. Witt 2 , Maria Charisi 3 ; Patricia Arévalo 4