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dc.contributor.authorCasassus, Simón
dc.contributor.authorVidal, Matías
dc.contributor.authorArce-Tord, Carla
dc.contributor.authorDickinson, Clive
dc.contributor.authorWhite, Glenn
dc.contributor.authorBurton, Michael G.
dc.contributor.authorIndermuehle, Balthasar T.
dc.contributor.authorHensley, Brandon S.
dc.date.accessioned2021-10-29T19:09:08Z
dc.date.available2021-10-29T19:09:08Z
dc.date.issued2021-03-01
dc.identifier10.1093/mnras/staa4016
dc.identifier.issn00358711
dc.identifier.urihttps://hdl.handle.net/20.500.12728/9662
dc.description.abstractCentimetre-wavelength radio continuum emission in excess of free-free, synchrotron, and Rayleigh-Jeans dust emission (excess microwave emission, EME), and often called 'anomalous microwave emission', is bright in molecular cloud regions exposed to UV radiation, i.e. in photodissociation regions (PDRs). The EME correlates with infrared (IR) dust emission on degree angular scales. Resolved observations of well-studied PDRs are needed to compare the spectral variations of the cm-continuum with tracers of physical conditions and of the dust grain population. The EME is particularly bright in the regions of the ρ Ophiuchi molecular cloud (ρ Oph) that surround the earliest type star in the complex, HD 147889, where the peak signal stems from the filament known as the ρ Oph W PDR. Here, we report on Australia Telescope Compact Array observations of ρ Oph W that resolve the width of the filament. We recover extended emission using a variant of non-parametric image synthesis performed in the sky plane. The multifrequency 17-39 GHz mosaics reveal spectral variations in the centimetre-wavelength continuum. At ∼30 arcsec resolutions, the 17-20 GHz intensities tightly follow the mid-IR, Icm ∝ I(8μm), despite the breakdown of this correlation on larger scales. However, while the 33-39 GHz filament is parallel to Infrared Array Camera 8 μm, it is offset by 15-20 arcsec towards the UV source. Such morphological differences in frequency reflect spectral variations, which we quantify spectroscopically as a sharp and steepening high-frequency cutoff, interpreted in terms of the spinning dust emission mechanism as a minimum grain size acutoff ∼ 6 ± 1 Å that increases deeper into the PDR.es_ES
dc.language.isoenes_ES
dc.publisherOxford University Presses_ES
dc.subjectISM: cloudses_ES
dc.subjectISM: individual objects: ρ Oph, Rho Oph W filament, SR4, DoAr21es_ES
dc.subjectphotodissociation regiones_ES
dc.subjectradiation mechanisms: generales_ES
dc.subjectradio continuum: generales_ES
dc.subjectsubmillimetre: ISMes_ES
dc.titleResolved spectral variations of the centimetre-wavelength continuum from the ρ Oph W photodissociationes_ES
dc.typeArticlees_ES


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