Free-floating planetary mass objects in LDN 1495 from Euclid Early Release Observations

TL;DR

This study uses Euclid's advanced imaging to identify potential free-floating planetary-mass objects in the Taurus region, providing new candidates and insights into their formation and prevalence.

Contribution

It demonstrates the effectiveness of Euclid data combined with ground-based observations to discover and analyze free-floating planetary-mass objects in a star-forming region.

Findings

Identified 15 candidate members of LDN 1495 based on proper motion and photometry.

Discovered 9 new objects with potential masses as low as 1-2 Jupiter masses.

Extrapolation suggests several dozen such objects may exist in Taurus.

Abstract

Context. Substellar objects, including brown dwarfs and free-floating planetary-mass objects, are a significant product of star formation. Their sensitivity to initial conditions and early dynamical evolution makes them especially valuable for studying planetary and stellar formation processes. Aims. We search for brown dwarfs and isolated planetary mass objects in a young star-forming region to better constrain their formation mechanisms. Methods. We took advantage of the Euclid unprecedented sensitivity, spatial resolution and wide field of view to search for brown dwarfs and free-floating planetary mass objects in the LDN 1495 region of the Taurus molecular clouds. We combined the recent Euclid Early Release Observations with older very deep ground-based images obtained over more than 20 yr to derive proper motions and multiwavelength photometry and to select members based on their morphology and their position in a proper motion diagram and in nine color-magnitude diagrams. Results. We identified 15 point sources whose proper motions, colors, and luminosity are consistent with being members of LDN 1495. Six of these objects were already known M9-L1 members. The remaining nine are newly identified sources whose spectral types might range from late-M to early-T types, with masses potentially as low as 1~2 MJup based on their luminosity and according to evolutionary models. However, follow-up observations are needed to confirm their nature, spectral type, and membership. When it is extrapolated to the entire Taurus star-forming region, this result suggests the potential presence of several dozen free-floating planetary mass objects.