Planck early results. XXV. Thermal dust in nearby molecular clouds
| Title | Planck early results. XXV. Thermal dust in nearby molecular clouds |
| Publication Type | Journal Article |
| Year of Publication | 2011 |
| Authors | ,, Abergel, A, Ade, PAR, Aghanim, N, Arnaud, M, Ashdown, M, Aumont, J, Baccigalupi, C, Balbi, A, Banday, AJ, Barreiro, RB, Bartlett, JG, Battaner, E, Benabed, K, Benoit, A, Bernard, JP, Bersanelli, M, Bhatia, R, Bock, JJ, Bonaldi, A, Bond, JR, Borrill, J, Bouchet, FR, Boulanger, F, Bucher, M, Burigana, C, Cabella, P, Cardoso, JF, Catalano, A, Cayon, L, Challinor, A, Chamballu, A, Chiang, LY, Chiang, C, Christensen, PR, Clements, DL, Colombi, S, Couchot, F, Coulais, A, Crill, BP, Cuttaia, F, Danese, L, Davies, RD, Davis, RJ, de Bernardis, P, de Gasperis, G, de Rosa, A, de Zotti, G, Delabrouille, J, Delouis, JM, Désert, FX, Dickinson, C, Dobashi, K, Donzelli, S, Dore, O, Dorl, U, Douspis, M, Dupac, X, Efstathiou, G, Ensslin, TA, Eriksen, HK, Finelli, F, Forni, O, Frailis, M, Franceschi, E, Galeotta, S, Ganga, K, Giard, M, Giardino, G, Giraud-Heraud, Y, Gonzalez-Nuevo, J, Gorski, KM, Gratton, S, Gregorio, A, Gruppuso, A, Guillet, V, Hansen, FK, Harrison, D, Henrot-Versille, S, Herranz, D, Hildebrandt, SR, Hivon, E, Hobson, M, Holmes, WA, Hovest, W, Hoyland, RJ, Huffenberger, KM, Jaffe, AH, Jones, A, Jones, WC, Juvela, M, Keihanen, E, Keskitalo, R, Kisner, TS, Kneissl, R, Knox, L, Kurki-Suonio, H, Lagache, G, Lamarre, JM, Lasenby, A, Laureijs, RJ, Lawrence, CR, Leach, S, Leonardi, R, Leroy, C, Linden-Vornle, M, Lopez-Caniego, M, Lubin, PM, Macias-Perez, JF, MacTavish, CJ, Maffei, B, Mandolesi, N, Mann, R, Maris, M, Marshall, DJ, Martin, P, Martinez-Gonzalez, E, Masi, S, Matarrese, S, Matthai, F, Mazzotta, P, McGehee, P, Meinhold, PR, Melchiorri, A, Mendes, L, Mennella, A, Mitra, S, Miville-Deschenes, MA, Moneti, A, Montier, L, Morgante, G, Mortlock, D, Munshi, D, Murphy, A, Naselsky, P, Natoli, P, Netterfield, CB, Norgaard-Nielsen, HU, Noviello, F, Novikov, D, Novikov, I, Osborne, S, Pajot, F, Paladini, R, Pasian, F, Patanchon, G, Perdereau, O, Perotto, L, Perrotta, F, Piacentini, F, Piat, M, Plaszczynski, S, Pointecouteau, E, Polenta, G, Ponthieu, N, Poutanen, T, Prezeau, G, Prunet, S, Puget, JL, Reach, WT, Rebolo, R, Reinecke, M, Renault, C, Ricciardi, S, Riller, T, Ristorcelli, I, Rocha, G, Rosset, C, Rubino-Martin, JA, Rusholme, B, Sandri, M, Santos, D, Savini, G, Scott, D, Seiffert, MD, Shellard, P, Smoot, GF, Starck, JL, Stivoli, F, Stolyarov, V, Sudiwala, R, Sygnet, JF, Tauber, JA, Terenzi, L, Toffolatti, L, Tomasi, M, Torre, JP, Tristram, M, Tuovinen, J, Umana, G, Valenziano, L, Verstraete, L, Vielva, P, Villa, F, Vittorio, N, Wade, LA, Wandelt, BD, Yvon, D, Zacchei, A, Zonca, A |
| Journal | Astronomy & Astrophysics |
| Volume | 536 |
| Date Published | Dec |
| ISBN Number | 0004-6361 |
| Accession Number | WOS:000298485100026 |
| Abstract | Planck allows unbiased mapping of Galactic sub-millimetre and millimetre emission from the most diffuse regions to the densest parts of molecular clouds. We present an early analysis of the Taurus molecular complex, on line-of-sight-averaged data and without component separation. The emission spectrum measured by Planck and IRAS can be fitted pixel by pixel using a single modified blackbody. Some systematic residuals are detected at 353 GHz and 143 GHz, with amplitudes around -7% and +13%, respectively, indicating that the measured spectra are likely more complex than a simple modified blackbody. Significant positive residuals are also detected in the molecular regions and in the 217 GHz and 100 GHz bands, mainly caused by the contribution of the J = 2 -> 1 and J = 1 -> 0 (CO)-C-12 and (CO)-C-13 emission lines. We derive maps of the dust temperature T, the dust spectral emissivity index beta, and the dust optical depth at 250 mu m tau(250). The temperature map illustrates the cooling of the dust particles in thermal equilibrium with the incident radiation field, from 16-17 K in the diffuse regions to 13-14 K in the dense parts. The distribution of spectral indices is centred at 1.78, with a standard deviation of 0.08 and a systematic error of 0.07. We detect a significant T - beta anti-correlation. The dust optical depth map reveals the spatial distribution of the column density of the molecular complex from the densest molecular regions to the faint diffuse regions. We use near-infrared extinction and Hi data at 21-cm to perform a quantitative analysis of the spatial variations of the measured dust optical depth at 250 mu m per hydrogen atom tau(250)/N-H. We report an increase of tau(250)/N-H by a factor of about 2 between the atomic phase and the molecular phase, which has a strong impact on the equilibrium temperature of the dust particles. |
