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Published August 10, 2025 | Version Published
Journal Article Open

BASS. XLVIII. [Ne V] λ3427 Emission in Powerful Nearby Active Galactic Nuclei

Creators

  • 1. ROR icon Tel Aviv University
  • 2. ROR icon Max Planck Institute for Extraterrestrial Physics
  • 3. ROR icon Excellence Cluster Origins
  • 4. ROR icon Diego Portales University
  • 5. ROR icon Peking University
  • 6. ROR icon University of Tarapacá
  • 7. ROR icon Eureka Scientific
  • 8. ROR icon Tohoku University
  • 9. ROR icon Waseda University
  • 10. ROR icon University of Hertfordshire
  • 11. ROR icon University of Maryland, College Park
  • 12. ROR icon Korea Astronomy and Space Science Institute
  • 13. ROR icon Yale University
  • 14. ROR icon ETH Zurich
  • 15. ROR icon California Institute of Technology
  • 16. ROR icon Leibniz Institute for Astrophysics Potsdam
  • 17. ROR icon Stanford University
  • 18. ROR icon European Southern Observatory
  • 19. ROR icon Jet Propulsion Lab
  • 20. Yale Center for Astronomy and Astrophysics, 52 Hillhouse Avenue, New Haven, CT 06511, USA

Abstract

We investigate the high-ionization, narrow [Ne V] λ3427 line emission in a sample of over 340 ultrahard X-ray (14–195 keV) selected active galactic nuclei (AGN) drawn from the BAT AGN Spectroscopic Survey project. The analysis includes measurements in individual and stacked spectra and considers several key AGN properties such as X-ray luminosity, supermassive black hole (SMBH) mass, Eddington ratios, and line-of-sight column density. The [Ne V] λ3427 line is robustly detected in ≈43% (146/341) of the AGN in our sample, with no significant trends between the detection rate and key AGN/SMBH properties. In particular, the detection rate remains high even at the highest levels of obscuration (>70% for log [N_H/cm⁻²]) ≳ 23). On the other hand, even some of our highest signal-to-noise spectra (S/N > 50) lack a robust [Ne v] detection. The typical (median) scaling ratios between [Ne v] line emission and (ultra)hard X-ray emission in our sample are log L[Ne V]/L₁₄₋₁₅₀ keV ≃ 3.75 and log L[Ne V]/L₂₋₁₀ KeV ≃ 3.36. The scatter on these scaling ratios, ≲0.5 dex, is comparable to, and indeed smaller than, what is found for other commonly used tracers of AGN radiative outputs (e.g., [O III] λ5007). Otherwise, we find no significant relations between the (relative) strength of [Ne v] and the basic AGN/SMBH properties under study, in contrast with simple expectations from models of SMBH accretion flows. Our results reaffirm the usability of [Ne v] as an AGN tracer even in highly obscured systems, including dual AGN and high-redshift sources.

Copyright and License

© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Acknowledgement

We thank the anonymous referee for the invaluable comments, which helped us improve the paper in several important aspects. We thank D. Baron for her help with partial correlation analyses and J. McKaig for useful discussions.

T.R. and B.T. acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement number 950533) and from the Israel Science Foundation (grant number 1849/19). C.R. acknowledges support from Fondecyt Regular grant 1230345, ANID BASAL project FB210003, and the China–Chile joint research fund. M.K. acknowledges support from NASA through ADAP award 80NSSC22K1126. K.O. acknowledges support from the Korea Astronomy and Space Science Institute under the R&D program (project No. 2025-1-831-01), supervised by the Korea AeroSpace Administration, and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT; RS-2025-00553982). Y.D. acknowledges financial support from a Fondecyt postdoctoral fellowship (3230310).

This research was supported by the Excellence Cluster ORIGINS, which is funded by the Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) under Germany’s Excellence Strategy—EXC 2094—390783311. B.T. acknowledges the hospitality of the Instituto de Estudios Astrofìsicos at Universidad Diego Portales and the Instituto de Astrofìsica at Pontificia Universidad Católica de Chile.

Facilities

VLT:Kueyen, Melipal (X-Shooter) - , Hale (DBSP) - , Swift - Swift Gamma-Ray Burst Mission (BAT).

Software References

MAAT (E. O. Ofek 2014), astropy (Astropy Collaboration et al. 2013, 2018).

Files

Reiss_2025_ApJ_989_88.pdf

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Additional details

Related works

Is new version of
Discussion Paper: arXiv:2507.08179 (arXiv)

Funding

European Research Council
950533
Israel Science Foundation
1849/19
Fondo Nacional de Desarrollo Científico y Tecnológico
1230345
Agencia Nacional de Investigación y Desarrollo
FB210003
Chinese Academy of Science South America Center for Astronomy
National Aeronautics and Space Administration
80NSSC22K1126
Korea Astronomy and Space Science Institute
2025-1-831-01
National Research Foundation of Korea
RS-2025-00553982
Fondo Nacional de Desarrollo Científico y Tecnológico
3230310
Deutsche Forschungsgemeinschaft
EXC 2094—390783311

Dates

Accepted
2025-06-24
Available
2025-08-06
Published

Caltech Custom Metadata

Caltech groups
Astronomy Department, Division of Physics, Mathematics and Astronomy (PMA)
Publication Status
Published