Search for Faint Lone Double-peaked H <i>α</i> Lines as Wandering IMBH Signatures in the MUSE Deep Field

Abstract Double-peaked H α emission profiles can serve as potential signatures of accreting intermediate-mass black holes (IMBHs), particularly those residing outside galactic nuclei. Such features are expected to arise from rotating disklike structures around black holes and can be used to identify elusive IMBH candidates. J. Sánchez Almeida et al. reported a sample of such double-peaked H α sources in the MUSE-Wide survey, interpreting them as potential signatures of wandering IMBHs after systematically excluding alternative explanations. Their method relied on constructing H α maps around central galaxies and visually identifying compact emission clumps in the surrounding halo regions. In this work, we revisit the analysis using the deeper MUSE Extremely Deep Field (MXDF) data and an automated detection algorithm tailored to identify such features. However, we do not recover any candidate population in MXDF, resulting in a null detection. This outcome is nevertheless informative, as it (1) highlights the inherent challenges in detecting IMBHs and (2) demonstrates the potential of automated approaches for future systematic searches, even though it did not yield a positive outcome in this case.