We investigate the possible presence of quasi-periodic oscillation (QPO) signals in 2103 blazars from the Zwicky Transient Facility (ZTF) time-domain survey. We detect a low-frequency QPO signal in five blazars observed over these 3.8-yr-long optical r-band ZTF light curves. These periods range from 144 to 196 d detected at ≳4σ significance levels in both the Lomb–Scargle periodogram and weighted wavelet Z-transform analyses. We find consistent results using the phase dispersion minimization technique. A similar peak is detected in the g-band light curves at a slightly lower significance of 3σ. Such nearly periodic signals on these time-scales in optical wavebands most likely originate from a precessing jet with high Lorentz factor, closely aligned to the observer’s line of sight or the movement of plasma blobs along a helical structure in the jet.
This content will become publicly available on July 1, 2024
- Award ID(s):
- 1909101
- NSF-PAR ID:
- 10440635
- Date Published:
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 675
- ISSN:
- 0004-6361
- Page Range / eLocation ID:
- A195
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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