Ade, P.A.R. and Aghanim, N. and Arnaud, M. and Ashdown, M. and Atrio-Barandela, F. and Aumont, J. and Baccigalupi, C. and Balbi, A. and Banday, A.J. and Barreiro, R.B. and Bartlett, J.G. and Battaner, E. and Benabed, K. and Benoit, A. and Bernard, J.-P. and Bersanelli, M. and Bonaldi, A. and Bond, J.R. and Borrill, J. and Bouchet, F.R. and Burigana, C. and Cabella, P. and Cardoso, J.-F. and Catalano, A. and Cayon, L. and Chary, R.-R. and Chiang, L.-Y. and Christensen, P.R. and Clements, D.L. and Colombo, L.P.L. and Coulais, A. and Crill, B.P. and Cuttaia, F. and Danese, L. and D'Arcangelo, O. and Davis, R.J. and De Bernardis, P. and de Gasperis, G. and de Rosa, A. and de Zotti, G. and Delabrouille, J. and Dickinson, C. and Diego, J.M. and Dobler, G. and Dole, H. and Donzelli, S. and Dore, O. and Dorl, U. and Douspis, M. and Dupac, X. and Efstathiou, G. and Enßlin, T.A. and Eriksen, H.K. and Finelli, F. and Forni, O. and Frailis, M. and Franceschi, E. and Galeotta, S. and Ganga, K. and Giard, M. and Giardino, G. and Gonzalez-Nuevo, J. and Gorski, K.M. and Gratton, S. and Gregorio, A. and Gruppuso, A. and Hansen, F.K. and Harrison, D. and Helou, G. and Henrot-Versille, S. and Hernandez-Monteagudo, C. and Hildebrandt, S.R. and Hivon, E. and Hobson, M. and Holmes, W.A. and Hornstrup, A. and Hovest, W. and Huffenberger, K.M. and Jaffe, T.R. and Jagemann, T. and Jewell, J. and Jones, W.C. and Juvela, M. and Keihanen, E. and Knoche, J. and Knox, L. and Kunz, M. and Kurki-Suonio, H. and Lagache, G. and Lahteenmaki, A. and Lamarre, J.-M. and Lasenby, A. and Lawrence, C.R. and Leach, S. and Leonardi, R. and Lilje, P.B. and Linden-Vornle, M. and Lopez-Caniego, M. and Lubin, P.M. and Macias-Perez, J.F. and Maffei, B. and Maino, D. and Mandolesi, N. and Maris, M. and Marshall, D.J. and Martin, P.G. and Martinez-Gonzalez, E. and Masi, S. and Massardi, M. and Matarrese, S. and Matthai, F. and Mazzotta, P. and Meinhold, P.R. and Melchiorri, A. and Mendes, L. and Mennella, A. and Mitra, S. and Moneti, A. and Montier, L. and Morgante, G. and Munshi, D. and Murphy, J.Anthony and Naselsky, P. and Natoli, P. and Norgaard-Nielsen, H.U. and Noviello, F. and Novikov, D. and Novikov, I. and Osborne, S. and Pajot, F. and Paladini, R. and Paoletti, D. and Partridge, B. and Pearson, T.J. and Perdereau, O. and Perrotta, F. and Piacentini, F. and Piat, M. and Pierpaoli, E. and Pietrobon, D. and Plaszczynski, S. and Pointecouteau, E. and Polenta, G. and Ponthieu, N. and Popa, L. and Poutanen, T. and Pratt, G.W. and Prunet, S. and Puget, J.-L. and Rachen, J.P. and Rebolo, R. and Reinecke, M. and Renault, C. and Ricciardi, S. and Riller, T. and Ristorcelli, I. and Rocha, G. and Rosset, C. and Rubino-Martin, J.A. and Rusholme, B. and Sandri, M. and Savini, G. and Schaefer, B.M. and Scott, D. and Smoot, G.F. and Spencer, L. and Stivoli, F. and Sudiwala, R. and Suur-Uski, A.-S. and Sygnet, J.-F. and Tauber, J.A. and Terenzi, L. and Toffolatti, L. and Tomasi, M. and Tristram, M. and Turler, M. and Umana, G. and Valenziano, L. and Van Tent, B. and Vielva, P. and Villa, F. and Vittorio, N. and Wade, L.A. and Wandelt, B.D. and White, M. and Yvon, D. and Zacchei, A. and Zonca, A. (2013) Planck intermediate results IX. Detection of the Galactic haze with Planck. Astronomy & Astrophysics, 554 (A139). ISSN 0004-6361

Preview

Download (3MB) | Preview

Abstract

Using precise full-sky observations from Planck, and applying several methods of component separation, we identify and characterise the emission from the Galactic “haze” at microwave wavelengths. The haze is a distinct component of diffuse Galactic emission, roughly centered on the Galactic centre, and extends to | b | ~ 35−50° in Galactic latitude and | l | ~ 15−20° in longitude. By combining the Planck data with observations from the Wilkinson Microwave Anisotropy Probe, we were able to determine the spectrum of this emission to high accuracy, unhindered by the strong systematic biases present in previous analyses. The derived spectrum is consistent with power-law emission with a spectral index of −2.56 ± 0.05, thus excluding free-free emission as the source and instead favouring hard-spectrum synchrotron radiation from an electron population with a spectrum (number density per energy) dN/dE ∝ E-2.1. At Galactic latitudes | b | < 30°, the microwave haze morphology is consistent with that of the Fermi gamma-ray “haze” or “bubbles”, while at b ~ −50° we have identified an edge in the microwave haze that is spatially coincident with the edge in the gamma-ray bubbles. Taken together, this indicates that we have a multi-wavelength view of a distinct component of our Galaxy. Given both the very hard spectrum and the extended nature of the emission, it is highly unlikely that the haze electrons result from supernova shocks in the Galactic disk. Instead, a new astrophysical mechanism for cosmic-ray acceleration in the inner Galaxy is implied.

Item Type:	Article
Keywords:	Planck Collaboration; Galaxy: nucleus; ISM: structure; ISM: bubbles; radio continuum: ISM;
Academic Unit:	Faculty of Science and Engineering > Experimental Physics
Item ID:	14265
Identification Number:	https://doi.org/10.1051/0004-6361/201220271
Depositing User:	Dr. Anthony Murphy
Date Deposited:	26 Mar 2021 16:52
Journal or Publication Title:	Astronomy & Astrophysics
Publisher:	EDP Sciences
Refereed:	Yes
URI:	Publisher
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

Repository Staff Only(login required)

Item control page

Downloads

Origin of downloads