Planck Collaboration, Abergel, A., Ade, P. A. R., Aghanim, N., Arnaud, M., Ashdown, M., Aumont, J., Baccigalupi, C., Balbi, A., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Battaner, E., Benabed, K., BenoƮt, A., Bernard, J. P., Bersanelli, M., Bhatia, R., Bock, J. J., Bonaldi, A., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bucher, M. et al. 2011. "Planck early results. XXI. Properties of the interstellar medium in the Galactic plane." Astronomy and Astrophysics, 536 A21. https://doi.org/10.1051/0004-6361/201116455.
Planck has observed the entire sky from 30 GHz to 857GHz. The observed foreground emission contains contributions from different phases of the interstellar medium (ISM). We have separated the observed Galactic emission into the different gaseous components (atomic, molecular and ionised) in each of a number of Galactocentric rings. This technique provides the necessary information to study dust properties (emissivity, temperature, etc.), as well as other emission mechanisms as a function