PKS J0805-0111: A Second Owens Valley Radio Observatory Blazar Showing Highly Significant Sinusoidal Radio Variability—The Tip of the Iceberg

Abstract

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© 2025. The Author(s). Published by the American Astronomical Society.

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Acknowledgement

This work is supported by NSF grants AST2407603 and AST2407604. We thank the California Institute of Technology and the Max Planck Institute for Radio Astronomy for supporting the OVRO 40 m program under extremely difficult circumstances over the last eight years in the absence of agency funding. Without this private support this paper would not have been written. We also thank all the volunteers who have enabled this work to be carried out. Prior to 2016, the OVRO program was supported by NASA grants NNG06GG1G, NNX08AW31G, NNX11A043G, and NNX13AQ89G from 2006 to 2016 and NSF grants AST-0808050, and AST-1109911 from 2008 to 2014. The UMRAO program received support from NSF grants AST-8021250, AST-8301234, AST-8501093, AST-8815678, AST-9120224, AST-9421979, AST-9900723, AST-0307629, AST-0607523, and earlier NSF awards, and from NASA grants NNX09AU16G, NNX10AP16G, NNX11AO13G, and NNX13AP18G. Additional funding for the operation of UMRAO was provided by the University of Michigan. The NANOGrav project receives support from National Science Foundation (NSF) Physics Frontier Center award number 1430284. T.H. was supported by the Academy of Finland projects 317383, 320085, 322535, and 345899. S.K. and K.T. acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2.20 research and innovation program under grant agreement No. 771282. I.L. and S.K. were funded by the European Union ERC-2022-STG—BOOTES—101076343. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. W.M. acknowledges support by the ANID BASAL project FB210003 and FONDECYT 11190853. R.R. and B.M. and P.V.d.l.P. acknowledge support from ANID Basal AFB-170002, from Núcleo Milenio TITANs (NCN2023_002), and CATA BASAL FB210003. P.V.d.l.P. also acknowledges support by the National Agency for Research and Development (ANID)/Scholarship Program/Doctorado Nacional/2023–21232103. M.V. performed part of this work at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). V.P. acknowledges support from the Foundation of Research and Technology—Hellas Synergy Grants Program through project MagMASim, jointly implemented by the Institute of Astrophysics and the Institute of Applied and Computational Mathematics and by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project 1552 CIRCE). K.T. acknowledges support from the Foundation of Research and Technology—Hellas Synergy Grants Program through project POLAR, jointly implemented by the Institute of Astrophysics and the Institute of Computer Science. I.L. was supported by the NASA Postdoctoral Program at the Marshall Space Flight Center, administered by Oak Ridge Associated Universities under contract with NASA. The authors acknowledge the Kultrun Astronomy Hybrid Cluster (projects Conicyt Programa de Astronomia FondoQuimal QUIMAL170001, QUIMAL220002 and Conicyt PIA ACT172033) for providing HPC resources that have contributed to the research results reported in this paper.