Ade, PAR;Aghanim, N;Arnaud, M;Ashdown, M;Aumont, J;Baccigalupi, C;Banday, AJ;Barreiro, RB;Bartolo, N;Battaner, E;Battye, R;Benabed, K;Bendo, GJ;Benoit-Levy, A;Bernard, JP;Bersanelli, M;Bielewicz, P;Bonaldi, A;Bonavera, L;Bond, JR;Borrill, J;Bouchet, FR;Burigana, C;Butler, RC;Calabrese, E;Cardoso, JF;Catalano, A;Chamballu, A;Chary, RR;Chen, X;Chiang, HC;Christensen, PR;Clements, DL;Colombo, LPL;Combet, C;Couchot, F;Coulais, A;Crill, BP;Curto, A;Cuttaia, F;Danese, L;Davies, RD;Davis, RJ;de Bernardis, P;de Rosa, A;de Zotti, G;Delabrouille, J;Dickinson, C;Diego, JM;Dole, H;Donzelli, S;Dore, O;Douspis, M;Ducout, A;Dupac, X;Efstathiou, G;Elsner, F;Ensslin, TA;Eriksen, HK;Finelli, F;Forni, O;Frailis, M;Fraisse, AA;Franceschi, E;Frejsel, A;Galeotta, S;Ganga, K;Giard, M;Giraud-Heraud, Y;Gjerlow, E;Gonzalez-Nuevo, J;Gorski, KM;Gregorio, A;Gruppuso, A;Hansen, FK;Hanson, D;Harrison, DL;Henrot-Versille, S;Hernandez-Monteagudo, C;Herranz, D;Hildebrandt, SR;Hivon, E;Hobson, M;Holmes, WA;Hornstrup, A;Hovest, W;Huffenberger, KM;Hurier, G;Israel, FP;Jaffe, AH;Jaffe, TR;Jones, WC;Juvela, M;Keihanen, E;Keskitalo, R;Kisner, TS;Kneissl, R;Knoche, J;Kunz, M;Kurki-Suonio, H;Lagache, G;Lahteenmaki, A;Lamarre, JM;Lasenby, A;Lattanzi, M;Lawrence, CR;Leonardi, R;Levrier, F;Liguori, M;Lilje, PB;Linden-Vornle, M;Lopez-Caniego, M;Lubin, PM;Macias-Perez, JF;Madden, S;Maffei, B;Maino, D;Mandolesi, N;Maris, M;Martin, PG;Martinez-Gonzalez, E;Masi, S;Matarrese, S;Mazzotta, P;Mendes, L;Mennella, A;Migliaccio, M;Miville-Deschenes, MA;Moneti, A;Montier, L;Morgante, G;Mortlock, D;Munshi, D;Murphy, JA;Naselsky, P;Nati, F;Natoli, P;Norgaard-Nielsen, HU;Noviello, F;Novikov, D;Novikov, I;Oxborrow, CA;Pagano, L;Pajot, F;Paladini, R;Paoletti, D;Partridge, B;Pasian, F;Pearson, TJ;Peel, M;Perdereau, O;Perrotta, F;Pettorino, V;Piacentini, F;Piat, M;Pierpaoli, E;Pietrobon, D;Plaszczynski, S;Pointecouteau, E;Polenta, G;Popa, L;Pratt, GW;Prunet, S;Puget, JL;Rachen, JP;Reinecke, M;Remazeilles, M;Renault, C;Ricciardi, S;Ristorcelli, I;Rocha, G;Rosset, C;Rossetti, M;Roudier, G;Rubino-Martin, JA;Rusholme, B;Sandri, M;Savini, G;Scott, D;Spencer, LD;Stolyarov, V;Sudiwala, R;Sutton, D;Suur-Uski, AS;Sygnet, JF;Tauber, JA;Terenzi, L;Toffolatti, L;Tomasi, M;Tristram, M;Tucci, M;Umana, G;Valenziano, L;Valiviita, J;Van Tent, B;Vielva, P;Villa, F;Wade, LA;Wandelt, BD;Watson, R;Wehus, IK;Yvon, D;Zacchei, A;Zonca, A

2015

October

Astronomy and Astrophysics

Planck intermediate results XXV. The Andromeda galaxy as seen by Planck

Published

8 ()

MULTIBAND IMAGING PHOTOMETER RADIO-CONTINUUM SURVEY PRE-LAUNCH STATUS SPITZER-SPACE-TELESCOPE FAR-INFRARED LUMINOSITY SPINNING DUST EMISSION RESOLUTION IRAS MAPS STAR-FORMATION RATES LOCAL GROUP GALAXIES COMPLETE CO SURVEY

582

The Andromeda galaxy (M 31) is one of a few galaxies that has sufficient angular size on the sky to be resolved by the Planck satellite. Planck has detected M 31 in all of its frequency bands, and has mapped out the dust emission with the High Frequency Instrument, clearly resolving multiple spiral arms and sub-features. We examine the morphology of this long-wavelength dust emission as seen by Planck, including a study of its outermost spiral arms, and investigate the dust heating mechanism across M 31. We find that dust dominating the longer wavelength emission (greater than or similar to 0.3 mm) is heated by the diffuse stellar population (as traced by 3.6 mu m emission), with the dust dominating the shorter wavelength emission heated by a mix of the old stellar population and star-forming regions (as traced by 24 mu m emission). We also fit spectral energy distributions for individual 5' pixels and quantify the dust properties across the galaxy, taking into account these different heating mechanisms, finding that there is a linear decrease in temperature with galactocentric distance for dust heated by the old stellar population, as would be expected, with temperatures ranging from around 22 K in the nucleus to 14 K outside of the 10 kpc ring. Finally, we measure the integrated spectrum of the whole galaxy, which we find to be well-fitted with a global dust temperature of (18.2 +/- 1.0) K with a spectral index of 1.62 +/- 0.11 (assuming a single modified blackbody), and a significant amount of free-free emission at intermediate frequencies of 20-60 GHz, which corresponds to a star formation rate of around 0.12 M-circle dot yr(-1). We find a 2.3 sigma detection of the presence of spinning dust emission, with a 30 GHz amplitude of 0.7 +/- 0.3 Jy, which is in line with expectations from our Galaxy.

LES ULIS CEDEX A

1432-0746

10.1051/0004-6361/201424643