Intensity and polarization of the atmospheric emission at millimetric wavelengths at Dome Concordia

• Published in: Monthly Notices of the Royal Astronomical Society
• Main Authors: Battistelli, E.S., Amico, G., Baù, A., Bergé, L., Bréelle, É., Charlassier, R., Collin, S., Cruciani, A., de Bernardis, P., Dufour, C., Dumoulin, L., Gervasi, M., Giard, M., Giordano, C., Giraud-Héraud, Y., Guglielmi, L., Hamilton, J.-C., Landé, J., Maffei, B., Maiello, M., Marnieros, S., Masi, S., Passerini, A., Piacentini, F., Piat, M., Piccirillo, L., Pisano, G., Polenta, G., Rosset, C., Salatino, M., Schillaci, A., Sordini, R., Spinelli, S., Tartari, A., Zannoni, M.
• Other Authors: CSNSM INSTR, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), CSNSM PS1, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS), BRAIN
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: atmospheric effects; instrumentation: polarimeters; site testing; cosmic background radiation; [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]; Antarc*; Antarctic
• Online Access: https://hal.in2p3.fr/in2p3-00706824; https://doi.org/10.1111/J.1365-2966.2012.20951.X

Atmospheric emission is a dominant source of disturbance in ground-based astronomy at millimetric wavelengths. The Antarctic plateau is recognized as an ideal site for millimetric and submillimetric observations, and the French/Italian base of Dome Concordia (Dome C) is among the best sites on Earth for these observations. In this paper, we present measurements at Dome C of the atmospheric emission in intensity and polarization at a 2-mm wavelength. This is one of the best observational frequencies for cosmic microwave background (CMB) observations when considering cosmic signal intensity, atmospheric transmission, detector sensitivity and foreground removal. Using the B-mode radiation interferometer (BRAIN)-pathfinder experiment, we have performed measurements of the atmospheric emission at 150 GHz. Careful characterization of the airmass synchronous emission has been performed, acquiring more than 380 elevation scans (i.e. 'skydip') during the third BRAIN-pathfinder summer campaign in 2009 December/2010 January. The extremely high transparency of the Antarctic atmosphere over Dome C is proven by the very low measured optical depth, <τI>= 0.050 ± 0.003 ± 0.011, where the first error is statistical and the second is the systematic error. Mid-term stability, over the summer campaign, of the atmosphere emission has also been studied. Adapting the radiative transfer atmosphere emission model am to the particular conditions found at Dome C, we also infer the level of the precipitable water vapor (PWV) content of the atmosphere, which is notoriously the main source of disturbance in millimetric astronomy (? mm). Upper limits on the airmass correlated polarized signal are also placed for the first time. The degree of circular polarization of atmospheric emission is found to be lower than 0.2 per cent [95 per cent confidence level (CL)], while the degree of linear polarization is found to be lower than 0.1 per cent (95 per cent CL). These limits include signal-correlated instrumental spurious polarization.