A LOFAR mini-survey for low-frequency radio emission from the nearest brown dwarfs

TL;DR

This study conducted a low-frequency radio survey of nearby, rapidly rotating brown dwarfs using LOFAR, establishing upper limits on their radio emissions and highlighting the need for significant resources for further detailed investigations.

Contribution

First systematic low-frequency radio survey of nearby brown dwarfs with LOFAR, providing upper limits and emphasizing the resource requirements for future studies.

Findings

Placed 3-sigma upper limits on flux density between 0.66 and 0.87 mJy.

Detected no significant radio emission from the targeted brown dwarfs.

Indicated substantial resource needs for detailed low-frequency radio studies.

Abstract

We have conducted a mini-survey for low-frequency radio emission from some of the closest brown dwarfs to the Sun with rapid rotation rates: SIMP J013656.5+093347, WISEPC J150649.97+702736.0, and WISEPA J174124.26+255319.5. We have placed robust 3-sigma upper limits on the flux density in the 111 - 169 MHz frequency range for these targets: WISE 1506: < 0.72 mJy; WISE 1741: < 0.87 mJy; SIMP 0136: < 0.66 mJy. At 8 hours of integration per target to achieve these limits, we find that systematic and detailed study of this class of object at LOFAR frequencies will require a substantial dedication of resources.