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arXiv · 2010.06337

Search for radio emission from the exoplanets Qatar-1b and WASP-80b near 150 MHz using the Giant Metrewave Radio Telescope

Abstract

We present radio observations made towards the exoplanets Qatar-1b and WASP-80b near 150~MHz with the Giant Meterwave Radio Telescope. These targets are relatively nearby irradiated giant exoplanets, a hot Jupiter and a hot Saturn, with sizes comparable to Jupiter but different masses and lower densities. Both the targets are expected to host extended H/He envelopes like Jupiter, with comparable or larger magnetic moments. No radio emission was detected from these exoplanets, with 3sigma limits of 5.9 and 5.2 mJy for Qatar-1b and WASP-80b, respectively, from these targeted observations. These are considerably deeper limits than those available for exoplanets from wide field surveys at similar frequencies. We also present archival VLA observations of a previously reported radio source close to Vir 61 (which has three exoplanets). The VLA observations resolve the source, which we identify as an extragalactic radio source, i.e. a chance association with Vir 61. Additionally, we cross-match a recent exoplanet catalogue with the TIFR GMRT Sky Survey ADR1 radio catalogue, but do not find any convincing associations.

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D. A. Green, N. Madhusudhan. 2020-11-09. Search for radio emission from the exoplanets Qatar-1b and WASP-80b near 150 MHz using the Giant Metrewave Radio Telescope. https://doi.org/10.1093/mnras%2Fstaa3208

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