Abstract
I introduce a systematic procedure for constructing complete and linearly independent sets of color structures for interactions of fields transforming under exotic representations of SU(N), in particular the SU(3) gauge group of QCD. It uncovers errors in previous results, starting with interactions of four fields including a single sextet.
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Acknowledgments
I thank Manuel Kunkel for triggering this paper by asking me to count the invariant tensors in the 8 ⊗ 8 ⊗ 6 ⊗ \( \overline{\textbf{6}} \) representation of SU(3). I thank Wolfgang Kilian, Jürgen Reuter for many productive discussions on making O’Mega more colorful. I also thank JR for useful comments on the manuscript. I thank Andreas Trautner (MPIK Heidelberg) for useful suggestions on the presentation and for pointing out errors in the original manuscript.
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Ohl, T. Birdtracks of exotic SU(N) color structures. J. High Energ. Phys. 2024, 203 (2024). https://doi.org/10.1007/JHEP06(2024)203
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DOI: https://doi.org/10.1007/JHEP06(2024)203