The nature of the radio source detected towards the exoplanet system 1RXS1609.1−210524

Abstract

Several studies have been carried out to detect radio emissions from known exoplanets. Some of these studies have resulted in tentative detections of radio sources near the position of known exoplanets. One such planet/brown dwarf around which a radio source was detected is 1RXS1609.1-210524 (hereafter 1RX) b. A radio source near 1RX was detected with the TIFR GMRT Sky Survey (TGSS) at 150 MHz and the NRAO VLA Sky Survey (NVSS) at 1.4 GHz. However, since these surveys’ spatial resolution was low, it was not possible to ascertain whether the radio emission originated from the system or a background source. This work presents results from the 1RX field’s targeted observations at 150 MHz, 325 MHz, and 610 MHz with Giant Meterwave Radio Telescope (GMRT). These observations have a higher angular resolution as compared to TGSS and NVSS. I detected the radio source near the position of 1RX at all frequencies with GMRT. I further used the VLA Sky Survey (VLASS) data at 3 GHz to determine the flux density and position at high frequency. With the targeted GMRT observations and observations from VLASS, I show that the radio emission does not originate from the 1RX b but is from a background source about ∼ 13″ away from the host star. Further, no radio emission was detected from the position of 1RX.