Detection of C₆₀ Combination Bands in the Near-IR Spectrum of Tc 1

Authors

• Morgan M. Giese, The University of Western Ontario
• Vincent J. Esposito, Chapman UniversityFollow
• Simon Van Schuylenbergh, The University of Western Ontario
• Jan Cami, The University of Western Ontario
• Els Peeters, The University of Western Ontario
• Charmi Bhatt, The University of Western Ontario
• Dries Van De Putte, The University of Western Ontario
• A. G. G. M. Tielens, University of Maryland at College Park
• Michael J. Barlow, University College London
• Jeronimo Bernard-Salas, Centre d’Etudes et de Recherche de Grasse (CERGA)
• Alessandra Candian, University of Amsterdam
• Bryan Changala, University of Colorado Boulder
• Nick L. J. Cox, Centre d’Etudes et de Recherche de Grasse (CERGA)
• Harriet L. Dinerstein, University of Texas at Austin
• D. A. García-Hernández, Instituto de Astrofísica de Canarias
• Marco A. Gómez-Muñoz, Universitat de Barcelona
• Kay Justtanont, Chalmers University of Technology
• Kathleen E. Kraemer, Boston College
• Eric Lagadec, Université Côte d’Azur
• Arturo Manchado, Instituto de Astrofísica de Canarias
• Ana Monreal Ibero, Leiden University
• Raghvendra Sahai, California Institute of Technology
• Ameek Sidhu, The University of Western Ontario
• G. C. Sloan, Space Telescope Science Institute
• N. C. Sterling, University of West Georgia
• Jeremy R. Walsh, European Southern Observatory
• Roger Wesson, University College London
• Joshua Cole Whitman, University of West Georgia
• Albert Zijlstra, The University of Manchester

Document Type

Article

Publication Date

6-15-2026

Abstract

We report the detection of a set of new near-infrared emission features between 3.5 and 5.2 μm in JWST/NIRSpec observations of Tc 1, the planetary nebula known for displaying the cleanest and most prominent mid-infrared cosmic fullerene spectrum. These broad features share the same spatial distribution as the well-known C₆₀ and C₇₀ mid-infrared emission bands, peaking in an asymmetric ring approximately 5″–6″ from the central star. Through comparison with new anharmonic quantum chemical calculations, we demonstrate that these features arise from C₆₀ combination bands, marking their first detection in an astrophysical environment. The total energy radiated in the combination bands amounts to ∼17% of the total energy emitted from all C₆₀ modes, with direct implications for fullerene cooling models. These near-infrared combination bands offer a promising new window for identifying and studying the molecular astrophysics of C₆₀ in sources where mid-infrared spectra are more complex.

Comments

This article was originally published in The Astrophysical Journal Letters, volume 1004, in 2026. https://doi.org/10.3847/2041-8213/ae76d5

Recommended Citation

Morgan M. Giese et al 2026, ApJL, 1004, L32. https://doi.org/10.3847/2041-8213/ae76d5

Copyright

The authors

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.