We propose an approach to search for axion dark matter with a specially designed superconducting radio frequency cavity, targeting axions with masses m  a  ≲ 10 −6 eV. Our approach exploits axion-induced transitions between nearly degenerate resonant modes of frequency ∼ GHz. A scan over axion mass is achieved by varying the frequency splitting between the two modes. Compared to traditional approaches, this allows for parametrically enhanced signal power for axions lighter than a GHz. The projected sensitivity covers unexplored parameter space for QCD axion dark matter for 10 −8 eV ≲ m  a  ≲ 10 −6 eV and axion-like particle dark matter as light as m  a  ∼ 10 −14 eV.

United States

Asher Berlin

France

Raffaele D’Agnolo

Sebastian Ellis

Christopher Nantista

Jeffrey Neilson

Philip Schuster

Sami Tantawi

Natalia Toro

Kevin Zhou

Axion dark matter detection by superconducting resonant frequency conversion

In quiver quantum mechanics with 4 supercharges, supersymmetric ground states are known to be in one-to-one correspondence with Dolbeault cohomology classes on the moduli space of stable quiver representations. Using supersymmetric localization, the refined Witten index can be expressed as a residue integral with a specific contour pre- scription, originally due to Jeffrey and Kirwan, depending on the stability parameters. On the other hand, the physical picture of quiver quantum mechanics describing interactions of BPS black holes predicts that the refined Witten index of a non-Abelian quiver can be expressed as a sum of indices for Abelian quivers, weighted by ‘single-centered invariants’. In the case of quivers without oriented loops, we show that this decomposition naturally arises from the residue formula, as a consequence of applying the Cauchy-Bose identity to the vector multiplet contributions. For quivers with loops, the same procedure produces a natural decomposition of the single-centered invariants, which remains to be elucidated. In the process, we clarify some under-appreciated aspects of the localization formula. Part of the results reported herein have been obtained by implementing the Jeffrey-Kirwan residue formula in a public Mathematica code.

Guillaume Beaujard

India

Swapnamay Mondal

Boris Pioline

Quiver indices and Abelianization from Jeffrey-Kirwan residues

We apply the Jeffrey-Kirwan method to compute the multiple integrals for the -type Nekrasov partition functions of four-dimensional supersymmetric gauge theories. We construct a graphical distinction rule to determine which poles are surrounded by their integration cycles. We compute the instanton correction of the “ ” pure super-Yang–Mills theory and find that for , which resembles the formula for the pure super-Yang–Mills theory with gauge group .

Japan

Satoshi Nakamura

On the Jeffrey–Kirwan residue of BCD -instantons