Intracluster Planetary Nebulae in the Hydra I cluster

TL;DR

This study employs the MSIS technique to identify 60 intracluster planetary nebulae in Hydra I, providing insights into the intracluster light and stellar populations in a nearby galaxy cluster.

Contribution

First detection and characterization of intracluster planetary nebulae in Hydra I using MSIS, linking PN counts to the central galaxy's stellar population.

Findings

Detected 60 ICPN candidates associated with ICL

PN counts align with expectations from the central galaxy's stellar population

Demonstrated the effectiveness of MSIS in cluster environments

Abstract

Using the Multislit Imaging Spectroscopy (MSIS) technique at the FORS2 spectrograph on VLT-UT1, we have identified 60 Intracluster Planetary Nebula (ICPN) candidates associated with the Intracluster Light (ICL) in the central region of the Hydra I cluster. Hydra I is a medium compact, relatively near (~50 Mpc), rich cluster in the southern hemisphere. Here we describe the criteria used to select emission sources and present the evidence for these PN candidates to be associated with the ICL in the Hydra I cluster. We also show, using the luminosity-specific planetary nebulae number, the alpha parameter, that the expected number of PNs associated with the stellar population of the central cD galaxy NGC 3311 in the cluster is close to the number of PNs detected.