The rate of extreme coronal line emitting galaxies in the Sloan Digital Sky Survey and their relation to tidal disruption events

Journal Article · Thu Oct 17 00:00:00 UTC 2024 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/stae2384 · OSTI ID:2570423

Callow, J.  ^[1]; Graur, O.  ^[2]; Clark, P.  ^[1]; Palmese, A.  ^[3]; Aguilar, J.  ^[4]; Ahlen, S.  ^[5]; BenZvi, S.  ^[6]; Brooks, D.  ^[7]; Claybaugh, T.  ^[4]; de la Macorra, A.  ^[8]; Doel, P.  ^[7]; Forero-Romero, J. E.  ^[9]; Gaztañaga, E.  ^[10]; Gontcho A Gontcho, S.  ^[4]; Lambert, A.  ^[4]; Landriau, M.  ^[4]; Manera, M.  ^[11]; Meisner, A.  ^[12]; Miquel, R.  ^[13]; Moustakas, J.  ^[14] ; Nie, J.  ^[15]; Poppett, C.  ^[16]; Prada, F.  ^[17]; Rezaie, M.  ^[18]; Rossi, G. ^[19]; Sanchez, E.  ^[20]; Silber, J.  ^[4]; Tarlé, G.  ^[21]; Weaver, B. A. ^[12]; Zhou, Z.  ^[15]

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1. Univ. of Portsmouth (United Kingdom)
2. Univ. of Portsmouth (United Kingdom); American Museum of Natural History (AMNH), New York, NY (United States)
3. Carnegie Mellon Univ., Pittsburgh, PA (United States)
4. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
5. Boston Univ., MA (United States)
6. Univ. of Rochester, NY (United States)
7. Univ. College London (United Kingdom)
8. Univ. Nacional Autonoma de Mexico (UNAM), Mexico City (Mexico)
9. Universidad de los Andes, Bogotá (Colombia)
10. Univ. of Portsmouth (United Kingdom); Institut d'Estudis Espacials de Catalunya (IEEC), Barcelona (Spain); Univ. Autonoma de Barcelona (Spain). Institute of Space Sciences (ICE, CSIC)
11. Univ. Autonoma de Barcelona (Spain). Institut de Fisica d'Altes Energies (IFAE); Barcelona Institute of Science and Technology (BIST), Tarragona (Spain)
12. National Optical-Infrared Astronomy Research Laboratory (NOIRLab), Tucson, AZ (United States)
13. Univ. Autonoma de Barcelona (Spain). Institucio Catalana de Recerca i Estudis Avancats (ICREA) and Institut de Fisica d'Altes Energies (IFAE); Barcelona Institute of Science and Technology (BIST), Tarragona (Spain)
14. Siena College, Loudonville, NY (United States)
15. Chinese Academy of Sciences (CAS), Beijing (China)
16. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)
17. Instituto de Astrofísica de Andalucía (CSIC), Granada (Spain)
18. Kansas State Univ., Manhattan, KS (United States)
19. Sejong Univ., Seoul (Korea, Republic of)
20. Research Centre for Energy, Environment and Technology (CIEMAT), Madrid (Spain)
21. Univ. of Michigan, Ann Arbor, MI (United States)

High-ionization iron coronal lines (CLs) are a rare phenomenon observed in galaxy and quasi-stellar object spectra that are thought to be created by high-energy emission from active galactic nuclei and certain types of transients. In cases known as extreme coronal line emitting galaxies (ECLEs), these CLs are strong and fade away on a time-scale of years. The most likely progenitors of these variable CLs are tidal disruption events (TDEs), which produce sufficient high-energy emission to create and sustain the CLs over these time-scales. To test the possible connection between ECLEs and TDEs, we present the most complete variable ECLE rate calculation to date and compare the results to TDE rates from the literature. To achieve this, we search for ECLEs in the Sloan Digital Sky Survey (SDSS). We detect sufficiently strong CLs in 16 galaxies, more than doubling the number previously found in SDSS. Using follow-up spectra from the Dark Energy Spectroscopic Instrument and Gemini Multi-Object Spectrograph, Wide-field Infrared Survey Explorer mid-infrared observations, and Liverpool Telescope optical photometry, we find that none of the nine new ECLEs evolve in a manner consistent with that of the five previously discovered variable ECLEs. Using this sample of five variable ECLEs, we calculate the galaxy-normalized rate of variable ECLEs in SDSS to be $$R_\mathrm{G}=3.6~^{+2.6}_{-1.8}~(\mathrm{statistical})~^{+5.1}_{-0.0}~(\mathrm{systematic})\times 10^{-6}~\mathrm{galaxy}^{-1}~\mathrm{yr}^{-1}$$. The mass-normalized rate is $$R_\mathrm{M}=3.1~^{+2.3}_{-1.5}~(\mathrm{statistical})~^{+4.4}_{-0.0}~(\mathrm{systematic})\times 10^{-17}~\mathrm{M_\odot ^{-1}}~\mathrm{yr}^{-1}$$ and the volumetric rate is $$R_\mathrm{V}=7~^{+20}_{-5}~(\mathrm{statistical})~^{+10}_{-0.0}~(\mathrm{systematic})\times 10^{-9}~\mathrm{Mpc}^{-3}~\mathrm{yr}^{-1}$$. Our rates are one to two orders of magnitude lower than TDE rates from the literature, which suggests that only 10–40 per cent of all TDEs produce variable ECLEs. Additional uncertainties in the rates arising from the structure of the interstellar medium have yet to be included.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Univ. of Rochester, NY (United States)
• Sponsoring Organization: National Science Foundation (NSF); Science and Technology Facilities Council (STFC); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-05CH11231; SC0008475
• OSTI ID: 2570423
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 1 Vol. 535; ISSN 1365-2966; ISSN 0035-8711
• Publisher: Oxford University PressCopyright Statement
• Country of Publication: United States
• Language: English