Study of Wolf-Rayet stars using uGMRT

TL;DR

This study used uGMRT observations to search for radio emissions from Wolf-Rayet stars WR 114 and WR 142, setting upper limits on their flux densities at low frequencies, which informs models of particle acceleration in massive star systems.

Contribution

First uGMRT observations of WR 114 and WR 142 at low frequencies, providing upper limits on their radio flux densities and constraining particle acceleration scenarios.

Findings

No radio detection at 735 and 1260 MHz for both stars.

Established 3σ upper limits on flux densities for WR 114 and WR 142.

Discussion of possible explanations for non-detections.

Abstract

In recent years, systems involving massive stars with large wind kinetic power have been considered as promising sites for investigating relativistic particle acceleration in low radio frequencies. With this aim, we observed two Wolf-Rayet systems, WR 114 and WR 142, using upgraded Giant Meterwave Radio Telescope observations in Band 4 (550-950 MHz) and Band 5 (1050-1450 MHz). None of the targets was detected at these frequencies. Based on the non-detection, we report 3$\sigma$ upper limits to the radio flux densities at 735 and 1260 MHz (123 and 66 $\mu$Jy for WR 114, and 111 and 96 $\mu$Jy for WR 142, respectively). The plausible scenarios to interpret this non-detection are presented.