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We perform an analysis of the diffuse low-frequency Galactic components inthe Southern part of the Gould Belt system (130^\circ\leq l\leq 230^\circ and-50^\circ\leq b\leq -10^\circ). Strong ultra-violet (UV) flux coming from theGould Belt super-association is responsible for bright diffuse foregrounds thatwe observe from our position inside the system and that can help us improve ourknowledge of the Galactic emission. Free-free emission and anomalous microwaveemission (AME) are the dominant components at low frequencies (\nu < 40 GHz),while synchrotron emission is very smooth and faint. We separate diffusefree-free emission and AME from synchrotron emission and thermal dust emissionby using Planck data, complemented by ancillary data, using the "CorrelatedComponent Analysis" (CCA) component separation method and we compare with theresults of cross-correlation of foreground templates with the frequency maps.We estimate the electron temperature T_e from H$\alpha$ and free-free emissionusing two methods (temperature-temperature plot and cross-correlation) and weobtain T_e ranging from 3100 to 5200 K, for an effective fraction of absorbingdust along the line of sight of 30% (f_d=0.3). We estimate the frequencyspectrum of the diffuse AME and we recover a peak frequency (in flux densityunits) of 25.5 \pm 1.5 GHz. We verify the reliability of this result withrealistic simulations that include the presence of biases in the spectral modelfor the AME and in the free-free template. By combining physical models forvibrational and rotational dust emission and adding the constraints from thethermal dust spectrum from Planck and IRAS we are able to get a gooddescription of the frequency spectrum of the AME for plausible values of thelocal density and radiation field.

We present the scaling relation between Sunyaev-Zeldovich (SZ) signal and stellar mass for almost 260,000 locally brightest galaxies (LBGs) selected from the Sloan Digital Sky Survey (SDSS). These are predominantly the central galaxies of their dark matter halos. We calibrate the stellar-to-halo mass conversion using realistic mock catalogues based on the Millennium Simulation. Applying a multi-frequency matched filter to the Planck data for each LBG, and averaging the results in bins of stellar mass, we measure the mean SZ signal down to M500 ∼ 2 × 1011 M⊙, with a clear indication of signal at even lower stellar mass. We derive the scaling relation between SZ signal and halo mass by assigning halo properties from our mock catalogues to the real LBGs and simulating the Planck observation process. This relation shows no evidence for deviation from a power law over a halo mass range extending from rich clusters down to M500 ~ 2 × 10 13 M⊙, and there is a clear indication of signal down to M500 ~ 4 × 1012 M ⊙. Planck's SZdetections in such low-mass halos imply that about a quarter of all baryons have now been seen in the form of hot halo gas, and that this gas must be less concentrated than the dark matter in such halos in order to remain consistent with X-ray observations. At the high-mass end, the measured SZ signal is 20% lower than found from observations of X-ray clusters, a difference consistent with the magnitude of Malmquist bias effects that were previously estimated for the X-ray sample. © 2013 ESO,.

We perform an analysis of the diffuse low-frequency Galactic components inthe Southern part of the Gould Belt system (130^\circ\leq l\leq 230^\circ and-50^\circ\leq b\leq -10^\circ). Strong ultra-violet (UV) flux coming from theGould Belt super-association is responsible for bright diffuse foregrounds thatwe observe from our position inside the system and that can help us improve ourknowledge of the Galactic emission. Free-free emission and anomalous microwaveemission (AME) are the dominant components at low frequencies (u < 40 GHz),while synchrotron emission is very smooth and faint. We separate diffusefree-free emission and AME from synchrotron emission and thermal dust emissionby using Planck data, complemented by ancillary data, using the "CorrelatedComponent Analysis" (CCA) component separation method and we compare with theresults of cross-correlation of foreground templates with the frequency maps.We estimate the electron temperature T_e from H$\alpha$ and free-free emissionusing two methods (temperature-temperature plot and cross-correlation) and weobtain T_e ranging from 3100 to 5200 K, for an effective fraction of absorbingdust along the line of sight of 30% (f_d=0.3). We estimate the frequencyspectrum of the diffuse AME and we recover a peak frequency (in flux densityunits) of 25.5 \pm 1.5 GHz. We verify the reliability of this result withrealistic simulations that include the presence of biases in the spectral modelfor the AME and in the free-free template. By combining physical models forvibrational and rotational dust emission and adding the constraints from thethermal dust spectrum from Planck and IRAS we are able to get a gooddescription of the frequency spectrum of the AME for plausible values of thelocal density and radiation field.

We present the scaling relation between Sunyaev-Zeldovich (SZ) signal and stellar mass for almost 260,000 locally brightest galaxies (LBGs) selected from the Sloan Digital Sky Survey (SDSS). These are predominantly the central galaxies of their dark matter halos. We calibrate the stellar-to-halo mass conversion using realistic mock catalogues based on the Millennium Simulation. Applying a multi-frequency matched filter to the Planck data for each LBG, and averaging the results in bins of stellar mass, we measure the mean SZ signal down to M500 ∼ 2 × 1011 M⊙, with a clear indication of signal at even lower stellar mass. We derive the scaling relation between SZ signal and halo mass by assigning halo properties from our mock catalogues to the real LBGs and simulating the Planck observation process. This relation shows no evidence for deviation from a power law over a halo mass range extending from rich clusters down to M500 ~ 2 × 10 13 M⊙, and there is a clear indication of signal down to M500 ~ 4 × 1012 M ⊙. Planck's SZdetections in such low-mass halos imply that about a quarter of all baryons have now been seen in the form of hot halo gas, and that this gas must be less concentrated than the dark matter in such halos in order to remain consistent with X-ray observations. At the high-mass end, the measured SZ signal is 20% lower than found from observations of X-ray clusters, a difference consistent with the magnitude of Malmquist bias effects that were previously estimated for the X-ray sample. © 2013 ESO,.

Using precise full-sky observations from Planck, and applying several methods of component separation, we identify and characterise the emission from the Galactic "haze" at microwave wavelengths. The haze is a distinct component of diffuse Galactic emission, roughly centered on the Galactic centre, and extends to | b | ∼ 35-50 in Galactic latitude and | l | ∼ 15-20 in longitude. By combining the Planck data with observations from the Wilkinson Microwave Anisotropy Probe, we were able to determine the spectrum of this emission to high accuracy, unhindered by the strong systematic biases present in previous analyses. The derived spectrum is consistent with power-law emission with a spectral index of-2.56 ± 0.05, thus excluding free-free emission as the source and instead favouring hard-spectrum synchrotron radiation from an electron population with a spectrum (number density per energy) dN/dE ∞ E-2.1. At Galactic latitudes | b | < 30, the microwave haze morphology is consistent with that of the Fermi gamma-ray "haze" or "bubbles", while at b ∼-50 we have identified an edge in the microwave haze that is spatially coincident with the edge in the gamma-ray bubbles. Taken together, this indicates that we have a multi-wavelength view of a distinct component of our Galaxy. Given both the very hard spectrum and the extended nature of the emission, it is highly unlikely that the haze electrons result from supernova shocks in the Galactic disk. Instead, a new astrophysical mechanism for cosmic-ray acceleration in the inner Galaxy is implied. © 2013 ESO.

We make use of the Planck all-sky survey to derive number counts and spectral indices of extragalactic sources-infrared and radio sources-from the Planck Early Release Compact Source Catalogue (ERCSC) at 100 to 857 GHz (3 mm to 350 μm). Three zones (deep, medium and shallow) of approximately homogeneous coverage are used to permit a clean and controlled correction for incompleteness, which was explicitly not done for the ERCSC, as it was aimed at providing lists of sources to be followed up. Our sample, prior to the 80% completeness cut, contains between 217 sources at 100 GHz and 1058 sources at 857 GHz over about 12 800 to 16 550 deg2 (31 to 40% of the sky). After the 80% completeness cut, between 122 and 452 and sources remain, with flux densities above 0.3 and 1.9 Jy at 100 and 857 GHz. The sample so defined can be used for statistical analysis. Using the multi-frequency coverage of the Planck High Frequency Instrument, all the sources have been classified as either dust-dominated (infrared galaxies) or synchrotron-dominated (radio galaxies) on the basis of their spectral energy distributions (SED). Our sample is thus complete, flux-limited and color-selected to differentiate between the two populations. We find an approximately equal number of synchrotron and dusty sources between 217 and 353 GHz; at 353 GHz or higher (or 217 GHz and lower) frequencies, the number is dominated by dusty (synchrotron) sources, as expected. For most of the sources, the spectral indices are also derived. We provide for the first time counts of bright sources from 353 to 857 GHz and the contributions from dusty and synchrotron sources at all HFI frequencies in the key spectral range where these spectra are crossing. The observed counts are in the Euclidean regime. The number counts are compared to previously published data (from earlier Planck results, Herschel, BLAST, SCUBA, LABOCA, SPT, and ACT) and models taking into account both radio or infrared galaxies, and covering a large range of flux densities. We derive the multi-frequency Euclidean level-the plateau in the normalised differential counts at high flux-density-and compare it to WMAP, Spitzer and IRAS results. The submillimetre number counts are not well reproduced by current evolution models of dusty galaxies, whereas the millimetre part appears reasonably well fitted by the most recent model for synchrotron-dominated sources. Finally we provide estimates of the local luminosity density of dusty galaxies, providing the first such measurements at 545 and 857 GHz. © 2013 ESO.

Taking advantage of the all-sky coverage and broadfrequency range of the Planck satellite, we study the Sunyaev-Zeldovich (SZ) and pressure profiles of 62 nearby massive clusters detected at high significance in the 14-month nominal survey. Careful reconstruction of the SZ signal indicates that most clusters are individually detected at least out to R500. By stacking the radial profiles, we have statistically detected the radial SZ signal out to 3 × R500, i.e., at a density contrast of about 50-100, though the dispersion about the mean profile dominates the statistical errors across the whole radial range. Our measurement is fully consistent with previous Planck results on integrated SZ fluxes, further strengthening the agreement between SZ and X-ray measurements inside R500. Correcting for the effects of the Planck beam, we have calculated the corresponding pressure profiles. This new constraint from SZ measurements is consistent with the X-ray constraints from XMM-Newton in the region in which the profiles overlap (i.e., [0.1-1] R 500), and is in fairly good agreement with theoretical predictions within the expected dispersion. At larger radii the average pressure profile is slightly flatter than most predictions from numerical simulations. Combining the SZ and X-ray observed profiles into a joint fit to a generalised pressure profile gives best-fit parameters [P0,c500,γ, α,β] = [6.41,1.81,0.31,1.33,4.13]. Using a reasonable hypothesis for the gas temperature in the cluster outskirts we reconstruct from our stacked pressure profile the gas mass fraction profile out to 3 R500. Within the temperature driven uncertainties, our Planck constraints are compatible with the cosmic baryon fraction and expected gas fraction in halos. © 2013 ESO.

Boomerang is a balloon-borne telescope designed for long duration (LDB) flights around Antarctica. The second LDB flight of Boomerang took place in January 2003. The primary goal of this flight was to measure the polarization of the CMB. The receiver uses polarization sensitive bolometers at 145 GHz. Polarizing grids provide polarization sensitivity at 245 and 345 GHz. We describe the Boomerang telescope noting changes made for 2003 LDB flight, and discuss some of the issues involved in the measurement of polarization with bolometers. Lastly, we report on the 2003 flight and provide an estimate of the expected results. © 2003 Elsevier B.V. All rights reserved.

Boomerang is a balloon-borne telescope designed for long duration (LDB) flights around Antarctica. The second LDB flight of Boomerang took place in January 2003. The primary goal of this flight was to measure the polarization of the CMB. The receiver uses polarization sensitive bolometers at 145 GHz. Polarizing grids provide polarization sensitivity at 245 and 345 GHz. We describe the Boomerang telescope noting changes made for 2003 LDB flight, and discuss some of the issues involved in the measurement of polarization with bolometers. Lastly, we report on the 2003 flight and provide an estimate of the expected results. © 2003 Elsevier B.V. All rights reserved.