Hadron Wavefunctions as a Probe of a Two Color Baryonic Medium

TL;DR

This paper investigates the properties of hadron wavefunctions in two-color QCD at high baryon chemical potential, revealing in-medium effects and evidence for a gapped Fermi surface through lattice simulations.

Contribution

It provides the first lattice simulation evidence of in-medium effects on hadron wavefunctions in two-color QCD at high chemical potential.

Findings

Hadrons become more compact as chemical potential increases

Wavefunction profiles indicate a dynamically-gapped Fermi surface

Results support the existence of in-medium modifications in the superfluid phase

Abstract

The properties of the ground state of two-color QCD at non-zero baryon chemical potential $\mu$ present an interesting problem in strongly-interacting gauge theory; in particular the nature of the physically-relevant degrees of freedom in the superfluid phase in the post-onset regime $\mu>m_\pi/2$ still needs clarification. In this study we present evidence for in-medium effects at high $\mu$ by studying the wavefunctions of mesonic and diquark states using orthodox lattice simulation techniques, made possible by the absence of a Sign Problem for the model with $N_f=2$. Our results show that beyond onset the spatial extent of hadrons decreases as $\mu$ grows, and that the wavefunction profiles are consistent with the existence of a dynamically-gapped Fermi surface in this regime.