Generating Function of single-centered Black Hole Index in CHL Models

Ranveer Kumar Singh

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arXiv · 2606.19479

Generating Function of single-centered Black Hole Index in CHL Models

Ranveer Kumar Singh

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Abstract

We present the construction of the generating function of single-centered black hole index in general $\mathbb{Z}_N$ CHL models. This is done by subtracting from the index of quarter BPS dyons, described by a meromorphic Siegel modular form, the generating function for the index of two-centered black holes. We use black hole bound state metamorphosis in CHL models for the construction of the generating function of two-centered black hole index. We prove the convergence of the generating function for the cases $N=2,3$.

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Ranveer Kumar Singh. 2026-06-17. Generating Function of single-centered Black Hole Index in CHL Models. https://arxiv.org/abs/2606.19479

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