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arXiv · 2504.15050

Potential Vibrational Modes Tied to Diffuse Interstellar Bands

Daniel Majaess·Halis Seuret·Tina A. Harriott·Cercis Morera-Boado·Ailish Sullivan·Lou Massa·Chérif F. Matta
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Abstract

Potential vibrational modes associated with diffuse interstellar bands (DIBs) could be discerned by examining energy differences between correlated DIBs. Consequently, $\approx 10^3$ higher correlated DIB pairs ($r-\sigma_r \ge 0.8$, $\ge 12$ sightlines) were extracted from the Apache Point Observatory DIB catalog, and their energy spacings computed. In this first macro exploratory step, a histogram possibly reveals chemical bond signatures of C$\equiv$C, C$\equiv$N, S$-$H, C$-$O, C$=$O, Si$-$H, N$-$H, C$-$H (aliphatic), C$\mathbf{^{\underline{...}}}$C (in-ring), and aromatics (C$-$H stretch, C$\mathbf{^{\underline{...}}}$C in-ring, oop C$-$H bending, and overtones). Continued research is required to (in)validate the histogram approach, mitigate noise, scrutinize maxima, break degeneracies, and converge upon an optimal framework.

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Daniel Majaess, Halis Seuret, Tina A. Harriott, Cercis Morera-Boado, Ailish Sullivan, Lou Massa, Chérif F. Matta. 2025-04-21. Potential Vibrational Modes Tied to Diffuse Interstellar Bands. https://arxiv.org/abs/2504.15050

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