Bibcode
Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chary, R.-R.; Chiang, H. C.; Christensen, P. R.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W. et al.
Referencia bibliográfica
Astronomy and Astrophysics, Volume 594, id.A25, 45 pp.
Advertised on:
9
2016
Revista
Número de citas
193
Número de citas referidas
173
Descripción
We discuss the Galactic foreground emission between 20 and 100 GHz based
on observations by Planck and WMAP. The total intensity in this part of
the spectrum is dominated by free-free and spinning dust emission,
whereas the polarized intensity is dominated by synchrotron emission.
The Commander component-separation tool has been used to separate the
various astrophysical processes in total intensity. Comparison with
radio recombination line templates verifies the recovery of the
free-free emission along the Galactic plane. Comparison of the
high-latitude Hα emission with our free-free map shows residuals
that correlate with dust optical depth, consistent with a fraction
(≈30%) of Hα having been scattered by high-latitude dust. We
highlight a number of diffuse spinning dust morphological features at
high latitude. There is substantial spatial variation in the spinning
dust spectrum, with the emission peak (in Iν) ranging from
below 20 GHz to more than 50 GHz. There is a strong tendency for the
spinning dust component near many prominent H ii regions to have a
higher peak frequency, suggesting that this increase in peak frequency
is associated with dust in the photo-dissociation regions around the
nebulae. The emissivity of spinning dust in these diffuse regions is of
the same order as previous detections in the literature. Over the entire
sky, the Commander solution finds more anomalous microwave emission
(AME) than the WMAP component maps, at the expense of synchrotron and
free-free emission. This can be explained by the difficulty in
separating multiple broadband components with a limited number of
frequency maps. Future surveys, particularly at 5-20 GHz, will greatly
improve the separation by constraining the synchrotron spectrum. We
combine Planck and WMAP data to make the highest signal-to-noise ratio
maps yet of the intensity of the all-sky polarized synchrotron emission
at frequencies above a few GHz. Most of the high-latitude polarized
emission is associated with distinct large-scale loops and spurs, and we
re-discuss their structure. We argue that nearly all the emission at
40deg > l > -90deg is part of the Loop I structure, and show that
the emission extends much further in to the southern Galactic hemisphere
than previously recognised, giving Loop I an ovoid rather than circular
outline. However, it does not continue as far as the "Fermi
bubble/microwave haze", making it less probable that these are part of
the same structure. We identify a number of new faint features in the
polarized sky, including a dearth of polarized synchrotron emission
directly correlated with a narrow, roughly 20deg long filament seen in
Hα at high Galactic latitude. Finally, we look for evidence of
polarized AME, however many AME regions are significantly contaminated
by polarized synchrotron emission, and we find a 2σ upper limit of
1.6% in the Perseus region.