# A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign

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## Abstract

**:**

## 1. Introduction

## 2. Search for QPOs

#### 2.1. Ground-Based Data

#### 2.2. K2 Observations

## 3. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## Abbreviations

BH | Black Hole |

SMBH | Supermassive Black Hole |

ISCO | Innermost Stable Circular Orbit |

PSD | Power Spectral Density |

LSP | Lomb–Scargle Periodogram |

QPO | Quasi-Periodic Oscillation |

WWZ | Weighted Wavelet Z-transform |

## References

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**Figure 1.**R-band light curve of OJ287 gathered during the 2015/2016 season. The December 2015 outburst is shown in the top panel, while the full-season light curve is in the bottom panel. The December 2015 high-amplitude flare turned out to be unpolarized.

**Figure 2.**Running Fourier transform Running Fourier transform (rFT) of the OJ287 data gathered during the 2015/2016 outburst.

**Figure 3.**(

**a**) Left panel: Lomb-Scargle periodogram (LSP) of the 2015/2016 data (blue line). The 99% confidence level is shown as the red contour; (

**b**) Right panel: the resulting graph from the wavelet Z-transform analysis.

© 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).

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**MDPI and ACS Style**

Zola, S.; Valtonen, M.; Bhatta, G.; Goyal, A.; Debski, B.; Baran, A.; Krzesinski, J.; Siwak, M.; Ciprini, S.; Gopakumar, A.; Jermak, H.; Nilsson, K.; Reichart, D.; Matsumoto, K.; Sadakane, K.; Gazeas, K.; Kidger, M.; Piirola, V.; Alicavus, F.; Baliyan, K.S.; Berdyugin, A.; Boyd, D.; Campas Torrent, M.; Campos, F.; Carrillo Gómez, J.; Caton, D.B.; Chavushyan, V.; Dalessio, J.; Dimitrov, D.; Drozdz, M.; Er, H.; Erdem, A.; Escartin Pérez, A.; Fallah Ramazani, V.; Filippenko, A.V.; Garcia, F.; Gómez Pinilla, F.; Gopinathan, M.; Haislip, J.B.; Harmanen, J.; Hudec, R.; Hurst, G.; Ivarsen, K.M.; Jelinek, M.; Joshi, A.; Kagitani, M.; Kaur, N.; Keel, W.C.; LaCluyze, A.P.; Lee, B.C.; Lindfors, E.; Lozano de Haro, J.; Moore, J.P.; Mugrauer, M.; Naves Nogues, R.; Neely, A.W.; Nelson, R.H.; Ogloza, W.; Okano, S.; Pandey, J.C.; Perri, M.; Pihajoki, P.; Poyner, G.; Provencal, J.; Pursimo, T.; Raj, A.; Reinthal, R.; Sadegi, S.; Sakanoi, T.; Sameer; Salto González, J.-L.; Schweyer, T.; Soldán Alfaro, F.C.; Karaman, N.; Sonbas, E.; Steele, I.; Stocke, J.T.; Strobl, J.; Takalo, L.O.; Tomov, T.; Tremosa Espasa, L.; Valdes, J.R.; Valero Pérez, J.; Verrecchia, F.; Webb, J.R.; Yoneda, M.; Zejmo, M.; Zheng, W.; Telting, J.; Saario, J.; Reynolds, T.; Kvammen, A.; Gafton, E.; Karjalainen, R.; Blay, P. A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign. *Galaxies* **2016**, *4*, 41.
https://doi.org/10.3390/galaxies4040041

**AMA Style**

Zola S, Valtonen M, Bhatta G, Goyal A, Debski B, Baran A, Krzesinski J, Siwak M, Ciprini S, Gopakumar A, Jermak H, Nilsson K, Reichart D, Matsumoto K, Sadakane K, Gazeas K, Kidger M, Piirola V, Alicavus F, Baliyan KS, Berdyugin A, Boyd D, Campas Torrent M, Campos F, Carrillo Gómez J, Caton DB, Chavushyan V, Dalessio J, Dimitrov D, Drozdz M, Er H, Erdem A, Escartin Pérez A, Fallah Ramazani V, Filippenko AV, Garcia F, Gómez Pinilla F, Gopinathan M, Haislip JB, Harmanen J, Hudec R, Hurst G, Ivarsen KM, Jelinek M, Joshi A, Kagitani M, Kaur N, Keel WC, LaCluyze AP, Lee BC, Lindfors E, Lozano de Haro J, Moore JP, Mugrauer M, Naves Nogues R, Neely AW, Nelson RH, Ogloza W, Okano S, Pandey JC, Perri M, Pihajoki P, Poyner G, Provencal J, Pursimo T, Raj A, Reinthal R, Sadegi S, Sakanoi T, Sameer, Salto González J-L, Schweyer T, Soldán Alfaro FC, Karaman N, Sonbas E, Steele I, Stocke JT, Strobl J, Takalo LO, Tomov T, Tremosa Espasa L, Valdes JR, Valero Pérez J, Verrecchia F, Webb JR, Yoneda M, Zejmo M, Zheng W, Telting J, Saario J, Reynolds T, Kvammen A, Gafton E, Karjalainen R, Blay P. A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign. *Galaxies*. 2016; 4(4):41.
https://doi.org/10.3390/galaxies4040041

**Chicago/Turabian Style**

Zola, S., M. Valtonen, G. Bhatta, A. Goyal, B. Debski, A. Baran, J. Krzesinski, M. Siwak, S. Ciprini, A. Gopakumar, H. Jermak, K. Nilsson, D. Reichart, K. Matsumoto, K. Sadakane, K. Gazeas, M. Kidger, V. Piirola, F. Alicavus, K. S. Baliyan, A. Berdyugin, D. Boyd, M. Campas Torrent, F. Campos, J. Carrillo Gómez, D. B. Caton, V. Chavushyan, J. Dalessio, D. Dimitrov, M. Drozdz, H. Er, A. Erdem, A. Escartin Pérez, V. Fallah Ramazani, A. V. Filippenko, F. Garcia, F. Gómez Pinilla, M. Gopinathan, J. B. Haislip, J. Harmanen, R. Hudec, G. Hurst, K. M. Ivarsen, M. Jelinek, A. Joshi, M. Kagitani, N. Kaur, W. C. Keel, A. P. LaCluyze, B. C. Lee, E. Lindfors, J. Lozano de Haro, J. P. Moore, M. Mugrauer, R. Naves Nogues, A. W. Neely, R. H. Nelson, W. Ogloza, S. Okano, J. C. Pandey, M. Perri, P. Pihajoki, G. Poyner, J. Provencal, T. Pursimo, A. Raj, R. Reinthal, S. Sadegi, T. Sakanoi, Sameer, J.-L. Salto González, T. Schweyer, F. C. Soldán Alfaro, N. Karaman, E. Sonbas, I. Steele, J. T. Stocke, J. Strobl, L. O. Takalo, T. Tomov, L. Tremosa Espasa, J. R. Valdes, J. Valero Pérez, F. Verrecchia, J. R. Webb, M. Yoneda, M. Zejmo, W. Zheng, J. Telting, J. Saario, T. Reynolds, A. Kvammen, E. Gafton, R. Karjalainen, and P. Blay. 2016. "A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign" *Galaxies* 4, no. 4: 41.
https://doi.org/10.3390/galaxies4040041