Dust reverberation mapping of Z229-15

Title

Dust reverberation mapping of Z229-15

Creator

Mandal A.K.; Rakshit S.; Stalin C.S.; Wylezalek D.; Patig M.K.; Sagar R.; Mathew B.; Muneer S.; Pal I.

Description

We report results of the dust reverberation mapping (DRM) on the Seyfert 1 galaxy Z229-15 at z = 0.0273. Quasi-simultaneous photometric observations for a total of 48 epochs were acquired during the period 2017 July to 2018 December in B, V, J, H and Ks bands. The calculated spectral index (?) between B and V bands for each epoch was used to correct for the accretion disc (AD) component present in the infrared light curves. The observed ? ranges between -0.99 and 1.03. Using cross-correlation function analysis we found significant time delays between the optical V and the AD corrected J, H and Ks light curves. The lags in the rest frame of the source are 12.52+10.00 -9.55 d (between V and J), 15.63+5.05 -5.11 d (between V and H) and 20.36+5.82 -5.68 d (between V and Ks). Given the large error bars, these lags are consistent with each other. However, considering the lag between V and Ks bands to represent the inner edge of the dust torus, the torus in Z229-15 lies at a distance of 0.017 pc from the central ionizing continuum. This is smaller than that expected from the radius luminosity (R-L) relationship known from DRM. Using a constant ? = 0.1 to account for theADcomponent, as is normally done in DRM, the deduced radius (0.025 pc) lies close to the expected R-L relation. However, usage of constant ? in DRM is disfavoured as the ? of the ionizing continuum changes with the flux of the source. 2021 Oxford University Press. All rights reserved.

Source

Monthly Notices of the Royal Astronomical Society, Vol-501, No. 3, pp. 3905-3915.

Date

2021-01-01

Publisher

Oxford University Press

Subject

galaxies: Active; galaxies: Individual: Z229-15; galaxies: Seyfert

Coverage

Mandal A.K., Department of Physics, CHRIST (Deemed to be University), Hosur Road, Bangalore, 560 029, India, Indian Institute of Astrophysics, Block II, Koramangala, Bangalore, 560 034, India; Rakshit S., Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital, 263002, India, Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Quantum, Vesilinnantie 5, University of Turku, FI-20014, Finland; Stalin C.S., Indian Institute of Astrophysics, Block II, Koramangala, Bangalore, 560 034, India; Wylezalek D., European Southern Observatory, Karl-Schwarzschildstr 2, Garching bei Muchen, D-85748, Germany; Patig M.K., European Southern Observatory, Karl-Schwarzschildstr 2, Garching bei Muchen, D-85748, Germany; Sagar R., Indian Institute of Astrophysics, Block II, Koramangala, Bangalore, 560 034, India; Mathew B., Department of Physics, CHRIST (Deemed to be University), Hosur Road, Bangalore, 560 029, India; Muneer S., Indian Institute of Astrophysics, Block II, Koramangala, Bangalore, 560 034, India; Pal I., Indian Institute of Astrophysics, Block II, Koramangala, Bangalore, 560 034, India

Rights

All Open Access; Green Open Access

Relation

ISSN: 358711; CODEN: MNRAA

Format

Online

Language

English

Type

Article

Identifier

https://doi.org/10.1093/mnras/staa3828

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