V488 Per Revisited: No Strong Mid-infrared Emission Features and No Evidence for Stellar/substellar Companions

We present characterization of the planetary system architecture for V488 Per, the dustiest main-sequence star known with a fractional infrared luminosity of approximate to 16%. Far-infrared imaging photometry confirms the existence of an outer planetary system dust population with a blackbody-fit temperature of approximate to 130 K. Mid-infrared spectroscopy probing the previously identified approximate to 800 K inner planetary system dust population does not detect any obvious solid-state emission features, suggesting either large grain sizes that mute such emission and/or grain compositions dominated by species like amorphous carbon and metallic iron, which do not produce such features. In the latter case, the presence of significant quantities of iron-rich material could be indicative of the active formation of a Mercury-like planet around V488 Per. In any event, the absence of solid-state emission features is very unusual among main-sequence stars with copious amounts of warm orbiting dust particles; we know of no other such star whose mid-infrared spectrum lacks such features. Combined radial velocity monitoring and adaptive optics imaging find no evidence for stellar/substellar companions within several hundred astronomical units of V488 Per.