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    The Carina Project. X. On the kinematics of old and intermediate-age stellar populations
    (2016-07-01)
    Bono, G.
    ;
    Nonino, M.
    ;
    Fabrizio, Michele 
    ;
    Buonanno, R. 
    We present new radial velocity (RV) measurements of old (horizontal branch) and intermediate-age (red clump) stellar tracers in the Carina dwarf spheroidal. They are based on more than 2,200 low-resolution spectra collected with VIMOS at VLT. The targets are faint (20
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    Planck 2015 results. V. LFI calibration
    (2015-05-01)
    Planck Collaboration
    ;
    Ade, P. A. R.
    ;
    Aghanim, N.
    ;
    Natoli, Paolo 
    ;
    Polenta, Gianluca 
    We present a description of the pipeline used to calibrate the Planck Low Frequency Instrument (LFI) timelines into thermodynamic temperatures for the Planck 2015 data release, covering 4 years of uninterrupted operations. As in the 2013 data release, our calibrator is provided by the spin-synchronous modulation of the CMB dipole, exploiting both the orbital and solar components. Our 2015 LFI analysis provides an independent Solar dipole estimate in excellent agreement with that of HFI and within $1sigma$ (0.3 % in amplitude) of the WMAP value. This 0.3 % shift in the peak-to-peak dipole temperature from WMAP and a global overhaul of the iterative calibration code increases the overall level of the LFI maps by 0.45 % (30 GHz), 0.64 % (44 GHz), and 0.82 % (70 GHz) in temperature with respect to the 2013 Planck data release, thus reducing the discrepancy with the power spectrum measured by WMAP. We estimate that the LFI calibration uncertainty is at the level of 0.20 % for the 70 GHz map, 0.26 % for the 44 GHz map, and 0.35 % for the 30 GHz map. We provide a detailed description of the impact of all the changes implemented in the calibration since the previous data release.
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    Planck intermediate results. XLII. Large-scale Galactic magnetic fields
    (2016-01-01)
    Planck Collaboration
    ;
    Adam, R.
    ;
    Ade, P. A. R.
    ;
    Natoli, Paolo 
    ;
    Polenta, Gianluca 
    Recent models for the large-scale Galactic magnetic fields in the literature were largely constrained by synchrotron emission and Faraday rotation measures. We select three different but representative models and compare their predicted polarized synchrotron and dust emission with that measured by the Planck satellite. We first update these models to match the Planck synchrotron products using a common model for the cosmic-ray leptons. We discuss the impact on this analysis of the ongoing problems of component separation in the Planck microwave bands and of the uncertain cosmic-ray spectrum. In particular, the inferred degree of ordering in the magnetic fields is sensitive to these systematic uncertainties. We then compare the resulting simulated emission to the observed dust emission and find that the dust predictions do not match the morphology in the Planck data, particularly the vertical profile in latitude. We show how the dust data can then be used to further improve these magnetic field models, particularly in the thin disc of the Galaxy where the dust is concentrated. We demonstrate this for one of the models and present it as a proof of concept for how we will advance these studies in future using complementary information from ongoing and planned observational projects.
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    Planck intermediate results. XXV. The Andromeda Galaxy as seen by Planck
    (2014-07-01)
    Ade, P. A. R.
    ;
    Aghanim, N.
    ;
    Arnaud, M.
    ;
    Natoli, Paolo 
    ;
    Polenta, Gianluca 
    The Andromeda Galaxy (M31) is one of a few galaxies that has sufficient angular size on the sky to be resolved by the Planck satellite. Planck has detected M31 in all of its frequency bands, and has mapped out the dust emission with the High Frequency Instrument, clearly resolving multiple spiral arms and sub-features. We examine the morphology of this long-wavelength dust emission as seen by Planck, including a study of its outermost spiral arms, and investigate the dust heating mechanism across M31. We find that dust dominating the longer wavelength emission ($gtrsim 0.3$ mm) is heated by the diffuse stellar population (as traced by 3.6 $mu$m emission), with the dust dominating the shorter wavelength emission heated by a mix of the old stellar population and star-forming regions (as traced by 24 $mu$m emission). We also fit spectral energy distributions (SEDs) for individual 5' pixels and quantify the dust properties across the galaxy, taking into account these different heating mechanisms, finding that there is a linear decrease in temperature with galactocentric distance for dust heated by the old stellar population, as would be expected, with temperatures ranging from around 22 K in the nucleus to 14 K outside of the 10 kpc ring. Finally, we measure the integrated spectrum of the whole galaxy, which we find to be well-fitted with a global dust temperature of ($18.9pm0.9$) K with a spectral index of $1.61pm0.11$ (assuming a single modified blackbody), and a significant amount of free-free emission at intermediate frequencies, which when converted into a star formation rate agrees well with the star formation estimate from H$alpha$ emission of 0.4$M_odot$ yr$^{-1}$. We see no evidence for spinning dust emission, with a 3$sigma$ upper limit of 1.26 Jy in the 20-60 GHz band.
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