Planck intermediate results. XII: Diffuse Galactic components in the Gould Belt system

Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.; Arnaud, M.; Ashdown, M.; Atrio Barandela, F.; Aumont, J.; Baccigalupi, C.; Balbi, A.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Battaner, E.; Bedini, L.; Benabed, K.; Beno?t, A.; Bernard, J. P.; Bersanelli, M.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Butler, R. C.; Cabella, P.; Cardoso, J. F.; Chen, X.; Chiang, L. Y.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Coulais, A.; Cuttaia, F.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Gasperis, G.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dobler, G.; Dole, H.; Donzelli, S.; Dor?, O.; Douspis, M.; Dupac, X.; En?lin, T. A.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; G?nova Santos, R. T.; Ghosh, T.; Giard, M.; Giardino, G.; Giraud H?raud, Y.; Gonz?lez Nuevo, J.; G?rski, K. M.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Harrison, D.; Hern?ndez Monteagudo, C.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Jaffe, T. R.; Jaffe, A. H.; Juvela, M.; Keih?nen, E.; Keskitalo, R.; Kisner, T. S.; Knoche, J.; Kunz, M.; Kurki Suonio, H.; Lagache, G.; L?hteenm?ki, A.; Lamarre, J. M.; Lasenby, A.; Lawrence, C. R.; Leach, S.; Leonardi, R.; Lilje, P. B.; Linden V?rnle, M.; Lubin, P. M.; Mac?as P?rez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Mart?nez Gonz?lez, E.; Masi, S.; Massardi, M.; Matarrese, Sabino; Mazzotta, P.; Melchiorri, A.; Mennella, A.; Mitra, S.; Miville Desch?nes, M. A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; N?rgaard Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C. A.; Pajot, F.; Paladini, R.; Paoletti, D.; Peel, M.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prunet, S.; Puget, J. L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Renault, C.; Ricciardi, S.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Mart?n, J. A. Rubi?o.; Rusholme, B.; Salerno, E.; Sandri, M.; Savini, G.; Scott, D.; Spencer, L.; Stolyarov, V.; Sudiwala, R.; Suur Uski, A. S.; Sygnet, J. F.; Tauber, J. A.; Terenzi, L.; Tibbs, C. T.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Valenziano, L.; Van Tent, B.; Varis, J.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Ysard, N.; Yvon, D.; Zacchei, A.; Zonca, A.

doi:10.1051/0004-6361/201321160

We perform an analysis of the diffuse low-frequency Galactic components in the southern part of the Gould Belt system (130° ≤ l ≤ 230° and -50° ≤ b ≤ -10°). Strong ultra-violet flux coming from the Gould Belt super-association is responsible for bright diffuse foregrounds that we observe from our position inside the system and that can help us improve our knowledge of the Galactic emission. Free-free emission and anomalous microwave emission (AME) are the dominant components at low frequencies (ν < 40 GHz), while synchrotron emission is very smooth and faint. We separated diffuse free-free emission and AME from synchrotron emission and thermal dust emission by using Planck data, complemented by ancillary data, using the correlated component analysis (CCA) component-separation method and we compared our results with the results of cross-correlation of foreground templates with the frequency maps. We estimated the electron temperature Te from Hα and free-free emission using two methods (temperature-temperature plot and cross-correlation) and obtained Te ranging from 3100 to 5200K for an effective fraction of absorbing dust along the line of sight of 30% (fd = 0.3). We estimated the frequency spectrum of the diffuse AME and recovered a peak frequency (in flux density units) of 25.5 ± 1.5 GHz. We verified the reliability of this result with realistic simulations that include biases in the spectral model for the AME and in the free-free template. By combining physical models for vibrational and rotational dust emission and adding the constraints from the thermal dust spectrum from Planck and IRAS, we are able to present a good description of the AME frequency spectrum for plausible values of the local density and radiation field.