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تسجيل مستخدم جديدBroad Band Photometric Reverberation Mapping of NGC 4395
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We present results of broad band photometric reverberation mapping (RM) to measure the radius of the broad line region, and subsequently the black hole mass (M$_{rm BH}$), in the nearby, low luminosity active galactic nuclei (AGN) NGC 4395. Using the Wise Observatorys 1m telescope equipped with the SDSS g$$, r$$ and i$$ broad band filters, we monitored NGC 4395 for 9 consecutive nights and obtained 3 light curves each with over 250 data points. The g$$ and r$$ bands include time variable contributions from H$beta$ and H$alpha$ (respectively) plus continuum. The i$$ band is free of broad lines and covers exclusively continuum. We show that by looking for a peak in the difference between the cross-correlation and the auto-correlation functions for all combinations of filters, we can get a reliable estimate of the time lag necessary to compute M$_{rm BH}$. We measure the time lag for H$alpha$ to be $3.6 pm 0.8 $ hours, comparable to previous studies using the line resolved spectroscopic RM method. We argue that this lag implies a black hole mass of M$_{rm BH} = (4.9 pm 2.6) times 10^{4}$ Msun .
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