Searching for debris discs in the 30 Myr open cluster IC 4665

Abstract

Context: Debris discs orbiting young stars are key to understand dust evolution and the planetary formation process. We take advantage of a recent membership analysis of the 30 Myr nearby open cluster IC 4665 based on the Gaia and DANCe surveys to revisit the disc population of this cluster. Aims: We aim to study the disc population of IC 4665 using Spitzer (MIPS and IRAC) and WISE photometry. Methods: We use several colour-colour diagrams with empirical photospheric sequences to detect the sources with an infrared excess. Independently, we also fit the spectral energy distribution (SED) of our debris disc candidates with the Virtual Observatory SED analyser (VOSA) which is capable of automatically detecting infrared excesses and provides effective temperature estimates. Results: We find six candidates debris disc host-stars (five with MIPS and one with WISE) and two of them are new candidates. We estimate a disc fraction of 24$\pm$10\% for the B-A stars, where our sample is expected to be complete. This is similar to what has been reported in other clusters of similar ages (Upper Centaurus Lupus, Lower Centaurus Crux, the $\beta$ Pictoris moving group, and the Pleiades). For solar type stars we find a disk fraction of 9$\pm$9%, lower than that observed in regions with comparable ages. Conclusions: Our candidates debris disc host-stars are excellent targets to be studied with ALMA or the future James Webb Space Telescope (JWST).

Accepted for publication in A&A

References in corpus (10)

• The Gaia mission
• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• Optical Images of an Exosolar Planet 25 Light Years from Earth
• VOSA: Virtual Observatory SED Analyzer. An application to the Collinder 69 open cluster
• Nearby debris disk systems with high fractional luminosity reconsidered
• Spitzer 24 Micron Observations of Open Cluster IC 2391 and Debris Disk Evolution of FGK Stars
• Spitzer 24 micron Survey of Debris Disks in the Pleiades
• Debris Disks in NGC 2547
• Detection of the lithium depletion boundary in the young open cluster IC 4665
• The first 40 million years of circumstellar disk evolution: the signature of terrestrial planet formation

Cited by in corpus (2)

• A $75\%$ Occurrence Rate of Debris Discs around F stars in the $\beta$ Pic Moving Group
• Influence of planets on debris disks in star clusters I: the 50 AU Jupiter