Constraints on spinning dust towards Galactic targets with the VSA: a tentative detection of excess microwave emission towards 3C396

Anna Scaife; David A. Green; Richard A. Battye; Rod D. Davies; Richard J. Davis; Clive Dickinson; Thomas Franzen; Ricardo Genova-Santos; Keith Grainge; Yaser A. Hafez; Michael P. Hobson; Anthony Lasenby; Guy G. Pooley; Nutan Rajguru; Rafael Rebolo; Jose Alberto Rubino-Martin; Richard D. E. Saunders; Paul F. Scott; David Titterington; Elizabeth Waldram; Robert A. Watson

doi:10.1111/j.1745-3933.2007.00305.x

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arXiv · astro-ph/0702473

Constraints on spinning dust towards Galactic targets with the VSA: a tentative detection of excess microwave emission towards 3C396

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Abstract

We present results from observations made at 33 GHz with the Very Small Array (VSA) telescope towards potential candidates in the Galactic plane for spinning dust emission. In the cases of the diffuse HII regions LPH96 and NRAO591 we find no evidence for anomalous emission and, in combination with Effelsberg data at 1.4 and 2.7 GHz, confirm that their spectra are consistent with optically thin free--free emission. In the case of the infra-red bright SNR 3C396 we find emission inconsistent with a purely non-thermal spectrum and discuss the possibility of this excess arising from either a spinning dust component or a shallow spectrum PWN, although we conclude that the second case is unlikely given the strong constraints available from lower frequency radio images.

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Anna Scaife, David A. Green, Richard A. Battye, Rod D. Davies, Richard J. Davis, Clive Dickinson, Thomas Franzen, Ricardo Genova-Santos, Keith Grainge, Yaser A. Hafez, Michael P. Hobson, Anthony Lasenby, Guy G. Pooley, Nutan Rajguru, Rafael Rebolo, Jose Alberto Rubino-Martin, Richard D. E. Saunders, Paul F. Scott, David Titterington, Elizabeth Waldram, Robert A. Watson. 2007-02-19. Constraints on spinning dust towards Galactic targets with the VSA: a tentative detection of excess microwave emission towards 3C396. https://doi.org/10.1111/j.1745-3933.2007.00305.x

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