A search for non-thermal radio emission from jets of massive young stellar objects. Issue 3 (18th April 2019)

• Record Type: Journal Article
• Authors: Obonyo, W O; Lumsden, S L; Hoare, M G; Purser, S J D; Kurtz, S E; Johnston, K G
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 486:Issue 3(2019)
• Page Start: 3664
• Page End: 3684
• Publication Date: 2019-04-18
• Subjects: stars: formation -- stars: massive -- stars: mass-loss -- stars: protostars; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz1091
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: Massive young stellar objects (MYSOs) have recently been shown to drive jets whose particles can interact with either the magnetic fields of the jet or ambient medium to emit non-thermal radiation. We report a search for non-thermal radio emission from a sample of 15 MYSOs to establish the prevalence of the emission in the objects. We used their spectra across the L, C, and Q bands along with spectral index maps to characterize their emission. We find that about 50 per cent of the sources show evidence for non-thermal emission with 40 per cent showing clear non-thermal lobes, especially sources of higher bolometric luminosity. The common or IRAS names of the sources that manifest non-thermal lobes are V645Cyg, IRAS 22134+5834, NGC 7538 IRS 9, IRAS 23262 + 640, AFGL 402d, and AFGL 490. All the central cores of the sources are thermal with corresponding mass-loss rates that lie in the range of ∼3 × 10 −7 to $\mathrm{7 \times 10^{-6}\, M_\odot \, yr^{-1}}$ . Given the presence of non-thermal lobes in some of the sources and the evidence of non-thermal emission from some spectral index maps, it seems that magnetic fields play a significant role in the jets of massive protostars. Also noted is that some of the sources show evidence of binarity and variability.