Abergel, A. and Ade, P.A.R. and Aghanim, N. and Arnaud, M. and Ashdown, M. 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 Bhatia, R. and Bock, J.J. and Bonaldi, A. and Bond, J.R. and Borrill, J. and Bouchet, F.R. and Boulanger, F. and Bucher, M. and Burigana, C. and Cabella, P. and Cardoso, J.-F. and Catalano, A. and Cayon, L. and Challinor, A. and Chamballu, A. and Chiang, L.-Y. and Chiang, C. and Christensen, P.R. and Clements, D.L. and Colombi, S. and Couchot, F. and Coulais, A. and Crill, B.P. and Cuttaia, F. and Danese, L. and Davies, R.D. and Davis, R.J. and De Bernardis, P. and de Gasperis, G. and de Rosa, A. and de Zotti, G. and Delabrouille, J. and Delouis, J.-M. and Desert, F.-X. and Dickinson, C. and Dobashi, K. 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 Giraud-Héraud, Y. and Gonzalez-Nuevo, J. and Gorski, K.M. and Gratton, S. and Gregorio, A. and Grupposo, A. and Guillet, V. and Hansen, F.K. and Harrison, D. and Henrot-Versille, S. and Herranz, D. and Hildebrandt, S.R. and Hivon, E. and Hobson, M. and Holmes, W.A. and Hovest, W. and Hoyland, R.J. and Huffenberger, K.M. and Jaffe, A.H. and Jones, A. and Jones, W.C. and Juvela, M. and Keihanen, E. and Keskitalo, R. and Kisner, T.S. and Kneissl, R. and Knox, L. and Kurki-Suonio, H. and Lagache, G. and Lamarre, J.-M. and Lasenby, A. and Laureijs, R.J. and Lawrence, C.R. and Leach, S. and Leonardi, R. and Leroy, C. and Linden-Vornle, M. and Lopez-Caniego, M. and Lubin, P.M. and Macias-Perez, J.F. and MacTavish, C.J. and Maffei, B. and Mandolesi, N. and Mann, R. and Maris, M. and Marshall, D.J. and Martin, P. and Martinez-Gonzalez, E. and Masi, S. and Matarrese, S. and Matthai, F. and Mazzotta, P. and McGehee, P. and Meinhold, P.R. and Melchiorri, A. and Mendes, L. and Mennella, A. and Mitra, S. and Miville-Deschenes, M.-A. and Moneti, A. and Montier, L. and Morgante, G. and Mortlock, D. and Munshi, D. and Murphy, J.Anthony and Naselsky, P. and Natoli, P. and Netterfield, C.B. and Norgaard-Nielsen, H.U. and Noviello, F. and Novikov, D. and Novikov, I. and Osborne, S. and Pajot, F. and Paladini, R. and Pasian, F. and Patanchon, G. and Perdereau, O. and Perotto, L. and Perrotta, F. and Piacentini, F. and Piat, M. and Plaszczynski, S. and Pointecouteau, E. and Polenta, G. and Ponthieu, N. and Poutanen, T. and Prezeau, G. and Prunet, S. and Puget, J.-L. and Reach, W.T. 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 Santos, D. and Savini, G. and Scott, D. and Seiffert, M.D. and Shellard, P. and Smoot, G.F. and Starck, J.-L. and Stivoli, F. and Stolyarov, V. and Sudiwala, R. and Sygnet, J.-F. and Tauber, J.A. and Terenzi, L. and Toffolatti, L. and Tomasi, M. and Torre, J.-P. and Tristram, M. and Tuovinen, J. and Umana, G. and Valenziano, L. and Verstraete, L. and Vielva, P. and Villa, F. and Vittorio, N. and Wade, L.A. and Wandelt, B.D. and Yvon, D. and Zacchei, A. and Zonca, A. (2011) Planck early results. XXV. Thermal dust in nearby molecular clouds. Astronomy & Astrophysics, 536 (A25). pp. 1-18. ISSN 0004-6361

Download (2MB)

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 12CO and 13CO emission lines. We derive maps of the dust temperature T, the dust spectral emissivity index β, and the dust optical depth at 250 μm τ250. 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 − β 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 μm per hydrogen atom τ250/NH. We report an increase of τ250/NH 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.

Item Type:	Article
Additional Information:	© ESO 2011 The original publication is available at DOI: 10.1051/0004-6361/201116483
Keywords:	Planck Collaboration; dust; extinction; ISM; structure; evolution; infrared; individual objects; Taurus-Auriga molecular cloud;
Academic Unit:	Faculty of Science and Engineering > Experimental Physics
Item ID:	4040
Depositing User:	Dr. Anthony Murphy
Date Deposited:	18 Dec 2012 15:41
Journal or Publication Title:	Astronomy & Astrophysics
Publisher:	EDP Sciences
Refereed:	Yes
URI:	http://www.aanda.org/ http://publications.edpsciences.org/
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