Planck intermediate results. XXIII. Galactic plane emission components derived from Planck with ancillary data
Abstract
Planck data when combined with ancillary data provide a unique opportunity to separate the diffuse emission components of the inner Galaxy. The purpose of the paper is to elucidate the morphology of the various emission components in the strong star-formation region lying inside the solar radius and to clarify the relationship between the various components. The region of the Galactic plane covered is l=300-0-60deg where star-formation is highest and the emission is strong enough to make meaningful component separation. The latitude widths in this longitude range lie between 1deg and 2deg, which correspond to FWHM z-widths of 100-200pc at a typical distance of 6kpc. The four emission components studied here are synchrotron, free-free, anomalous microwave emission (AME), and thermal (vibrational) dust emission. These components are identified by constructing spectral energy distributions (SEDs) at positions along the Galactic plane using the wide frequency coverage of Planck (28.4-857GHz) in combination with low-frequency radio data at 0.408-2.3GHz plus WMAP data at 23-94GHz, along with far-infrared (FIR) data from DIRBE and IRAS. The free-free component is determined from radio recombination line (RRL) data. AME is found to be comparable in brightness to the free-free emission on the Galactic plane in the frequency range 20-40GHz with a width in latitude similar to that of the thermal dust; it comprises 45+/-1% of the total 28.4GHz emission in the longitude range l=300-0-60deg. The free-free component is the narrowest, reflecting the fact that it is produced by current star-formation as traced by the narrow distribution of OB stars. It is the dominant emission on the plane between 60 and 100GHz. RRLs from this ionized gas are used to assess its distance, leading to a free-free z-width of FWHM ~100pc...(abridged)
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Cite
@article{arxiv.1406.5093,
title = {Planck intermediate results. XXIII. Galactic plane emission components derived from Planck with ancillary data},
author = {Planck Collaboration and P. A. R. Ade and N. Aghanim and M. I. R. Alves and M. Arnaud and M. Ashdown and F. Atrio-Barandela and J. Aumont and C. Baccigalupi and A. J. Banday and R. B. Barreiro and E. Battaner and K. Benabed and A. Benoit-Lévy and J. -P. Bernard and M. Bersanelli and P. Bielewicz and J. Bobin and A. Bonaldi and J. R. Bond and F. R. Bouchet and F. Boulanger and C. Burigana and J. -F. Cardoso and A. Catalano and A. Chamballu and H. C. Chiang and P. R. Christensen and D. L. Clements and S. Colombi and L. P. L. Colombo and C. Combet and F. Couchot and B. P. Crill and F. Cuttaia and L. Danese and R. D. Davies and R. J. Davis and P. de Bernardis and A. de Rosa and G. de Zotti and J. Delabrouille and C. Dickinson and J. M. Diego and S. Donzelli and O. Doré and M. Douspis and X. Dupac and G. Efstathiou and T. A. Enßlin and H. K. Eriksen and F. Finelli and O. Forni and M. Frailis and E. Franceschi and S. Galeotta and K. Ganga and R. T. Génova-Santos and T. Ghosh and M. Giard and G. Giardino and Y. Giraud-Héraud and J. González-Nuevo and K. M. Górski and A. Gregorio and A. Gruppuso and F. K. Hansen and D. L. Harrison and S. Henrot-Versillé and D. Herranz and S. R. Hildebrandt and E. Hivon and M. Hobson and A. Hornstrup and W. Hovest and K. M. Huffenberger and A. H. Jaffe and T. R. Jaffe and W. C. Jones and E. Keihänen and R. Keskitalo and T. S. Kisner and R. Kneissl and J. Knoche and M. Kunz and H. Kurki-Suonio and G. Lagache and A. Lähteenmäki and J. -M. Lamarre and A. Lasenby and C. R. Lawrence and R. Leonardi and M. Liguori and P. B. Lilje and M. Linden-Vørnle and M. López-Caniego and P. M. Lubin and J. F. Macías-Pérez and D. Maino and N. Mandolesi and P. G. Martin and E. Martínez-González and S. Masi and M. Massardi and S. Matarrese and P. Mazzotta and P. R. Meinhold and A. Melchiorri and L. Mendes and A. Mennella and M. Migliaccio and S. Mitra and M. -A. Miville-Deschênes and A. Moneti and L. Montier and G. Morgante and D. Mortlock and D. Munshi and J. A. Murphy and P. Naselsky and F. Nati and P. Natoli and H. U. Nørgaard-Nielsen and F. Noviello and D. Novikov and I. Novikov and C. A. Oxborrow and L. Pagano and F. Pajot and R. Paladini and D. Paoletti and F. Pasian and T. J. Pearson and M. Peel and O. Perdereau and F. Perrotta and F. Piacentini and M. Piat and E. Pierpaoli and D. Pietrobon and S. Plaszczynski and E. Pointecouteau and G. Polenta and N. Ponthieu and L. Popa and G. W. Pratt and S. Prunet and J. -L. Puget and J. P. Rachen and W. T. Reach and R. Rebolo and W. Reich and M. Reinecke and M. Remazeilles and C. Renault and S. Ricciardi and T. Riller and I. Ristorcelli and G. Rocha and C. Rosset and G. Roudier and J. A. Rubiño-Martín and B. Rusholme and M. Sandri and G. Savini and D. Scott and L. D. Spencer and V. Stolyarov and A. W. Strong and D. Sutton and A. -S. Suur-Uski and J. -F. Sygnet and J. A. Tauber and D. Tavagnacco and L. Terenzi and C. T. Tibbs and L. Toffolatti and M. Tomasi and M. Tristram and M. Tucci and L. Valenziano and J. Valiviita and B. Van Tent and J. Varis and P. Vielva and F. Villa and L. A. Wade and B. D. Wandelt and R. Watson and D. Yvon and A. Zacchei and A. Zonca},
journal= {arXiv preprint arXiv:1406.5093},
year = {2015}
}
Comments
28 pages, A&A (accepted), on behalf of Planck Collaboration. Minor formatting and reference updates