Cosmology with the CMB and its Polarization 2015

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    The primordial CMB 4-point function
    (2015) Smith, Kendrick
    We present a general framework for data analysis of the primordial 4-point function of the CMB. We classify physically motivated signals, discuss data analysis challenges, and present results from WMAP and Planck.
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    Did m2φ2 bite the dust? A closer look at ns and r
    (2015) Flauger, Raphael
    I will review measurements of the angular power spectrum of temperature perturbations from Planck data by the Planck collaboration and by Renee Hlozek, David Spergel and myself and will discuss the small differences in the scalar spectral index between the two. I will then combine these measurements with the recent measurement of the polarization of the cosmic microwave background by BICEP2 as well as the measurements of polarized emission from dust by the Planck collaboration to derive the current (but soon outdated) constraints on the spectral index of scalar perturbations and the amount of primordial gravitational waves. I will show that the data now disfavors the simplest model of inflation at 2-3 sigma depending on the choice of likelihood for the temperature data.
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    Did m2φ2 bite the dust? A closer look at ns and r
    (2015) Rlauger, Raphael
    I will review measurements of the angular power spectrum of temperature perturbations from Planck data by the Planck collaboration and by Renee Hlozek, David Spergel and myself and will discuss the small differences in the scalar spectral index between the two. I will then combine these measurements with the recent measurement of the polarization of the cosmic microwave background by BICEP2 as well as the measurements of polarized emission from dust by the Planck collaboration to derive the current (but soon outdated) constraints on the spectral index of scalar perturbations and the amount of primordial gravitational waves. I will show that the data now disfavors the simplest model of inflation at 2-3 sigma depending on the choice of likelihood for the temperature data.
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    Control of Systematics for the Primordial Inflation Explorer (PIXIE)
    (2015) Fixsen, Dale
    Talk will include an examination of systematic effects of emission from mirrors, calibrator, grids and other areas within the PIXIE instrument. The systematic effects of detector non-ideality and asymmetry will also be presented. These show that the residual systematic effects do not jeopardize either the polarization or spectrum measurements and that there are sufficient safeguards to find and calibrate out the most likely errors.
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    Constraining Fundamental Physics with Planck
    (2015) Rocha, Graca
    In this talk we will present constraints on the temporal and spatial variation of fundamental constants such as fine structure constant, α, mass of the electron, $m_e$. etc. and investigate the degeneracies with cosmological parameters such as $H_0$
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    The Astrophysics of Dust Polarization
    (2015) Boulanger, Francois
    The Planck satellite has produced the first whole sky map of polarization|at sub-mm and mm wavelengths. This is an immense step forward from|earlier polarization observations of Galactic dust. The data is revealing a new|sky we have started to explore. For the first time, we have the data needed to characterize the structure of the Galactic magnetic field and its coupling with interstellar matter and turbulence, in the diffuse interstellar medium and molecular clouds. Our analysis of the data also involves the characterization of the polarization properties of dust. I will introduce the science questions we are investigating and review our published results. I will connect what we are learning on the astrophysics of dust polarization to the structure of the dusty polarized screen to CMB polarization at high Galactic latitudes.
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    Weak Lensing of CMB Polarizatoin
    (2015) Seljak, Uros
    I will review the lensing effects in CMB polarization, both as a science driver and as a nuisance. I will discuss reconstruction methods and delensing methods to remove it from CMB polarization, and the ultimate reach of these methods in terms of gravity wave B modes.
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    PLANCK 2015 OVERVIEW & SYSTEMATICS
    (2015) Lawrence, Charles
    I will give an overview of the Planck 2015 results and discuss the most important systematics affecting the two instruments
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    Primordial Inflation Polarization Explorer
    (2015) Kogut, Al
    The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne instrument to search for inflationary B modes on angular scales 30 arcmin to 90 degrees (2 < ell < 400). PIPER combines cold (1.5 K) optics, 5120 bolometric detectors, and rapid polarization modulation using VPM grids to achieve both high sensitivity and excellent control of systematic errors. A series of flights alternating between northern and southern hemisphere launch sites will produce maps in Stokes I, Q, U, and V parameters at frequencies 200, 270, 350, and 600 GHz (wavelengths 1500, 1100, 850, and 500 microns) covering 85% of the sky. We describe the PIPER instrument and discuss the current status and expected science returns from the mission.
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    Cosmology Large Angular Scale Surveyor
    (2015) Eimer, Joseph
    The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the imprint of gravitational waves from inflation in the polarization of the cosmic microwave background. CLASS is a multi-frequency array of four telescopes to be deployed in the Atacama Desert in Chile. From this site, CLASS will observe 70% of the sky at four frequency bands centered at 38, 93, 148, and 217 GHz - designed to straddle the full-sky galactic foreground minimum. The large survey area enables CLASS to characterize the B-mode and E-mode power spectra on both the reionization and recombination scales. Simulations including the presence of foregrounds suggest the CLASS strategy of combining large sky coverage, control of systematic errors, signal stability, and high sensitivity will allow detection of the tensor-to-scalar ratio down to the level of r=0.01 and enable cosmic-variance-limited measurements of the optical depth to reionization. In this talk, I present an overview of the CLASS strategy for measuring the E-modes and B-modes at the largest angular scales and give an update on the project status.
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    Polarization Measurements with the South Pole Telescope
    (2015) Benson, Bradford
    I will give an overview of the SPTpol and SPT-3G experiments. SPTpol is a polarization-sensitive camera designed to measure the polarization of the cosmic microwave background (CMB) deployed on the 10 meter South Pole Telescope (SPT) in January 2012. I will present recent results of the E-mode and TE-mode CMB power spectra, derived from 100 square degrees observed in the first year of observations. Additionally I will show B-mode power spectra, measurements of the gravitational lensing potential, and briefly report on the status of the full 500 square degree SPTpol survey. Finally, I will discuss the status of SPT’s next-generation camera, SPT-3G, which will consist of 16,200 polarization-sensitive transition-edge sensors (TES), contained within 2700 multi-chroic pixels with observing bands centered at 95, 150, and 220 GHz, and scheduled to achieve first light in January 2016.
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    LSPE the Large‐Scale Polarization Explorer
    (2015) de Bernardis, Paolo
    The LSPE is a balloon-borne mission aimed at measuring the polarization of the Cosmic Microwave Background (CMB) at large angular scales, and in particular to constrain the curl component of CMB polarization (B-modes) produced by tensor perturbations generated during cosmic inflation, in the very early universe. Its primary target is the detection of the power spectrum of B-modes at multipoles covering both the reionization peak and the recombination peak, with a sensitivity corresponding to r = 0.02, at 99.7% confidence. A second target is to produce wide maps of foreground polarization generated in our Galaxy by synchrotron emission and interstellar dust emission. These will be important to map Galactic magnetic fields and to study the properties of ionized gas and of diffuse interstellar dust in our Galaxy. The mission is optimized for large angular scales, with coarse angular resolution (around 1.5 degrees FWHM), and wide sky coverage (25% of the sky). The payload will fly in a circumpolar long duration balloon mission during the polar night. Using the Earth as a giant solar shield, the instrument will spin in azimuth, observing a large fraction of the northern sky. The payload will host two instruments. An array of coherent polarimeters using cryogenic HEMT amplifiers will survey the sky at 43 and 90 GHz. An array of bolometric polarimeters, using large throughput multi-mode bolometers and rotating Half Wave Plates (HWP), will survey the same sky region in three bands at 140, 220 and 240 GHz. The wide frequency coverage will allow optimal control of the polarized foregrounds, with comparable angular resolution at all frequencies.
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    Odd Tensor Modes from Inflation
    (2015) Sorbo, Lorenzo
    The existence of a primordial spectrum of gravitational waves is a generic prediction of inflation. Here I will discuss how the coupling of a pseudoscalar inflaton to a gauge field can induce, in a two-step process, gravitational waves with unusual properties such as: (i) a net chirality (ii) a blue spectrum (iii) being detectable in the (relatively) near future by ground-based gravitational interferometers (iv) large nongaussianities even if the scalar perturbations are approximately gaussian
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    Cosmology from the Planck 2- and 4-pt functions
    (2015) Challinor, Anthony
    I review constraints on cosmological parameters from the Planck 2014 temperature and polarization data. Particular emphasis will be given to the extraction and interpretation of the effects of weak gravitational lensing.
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    QUBIC, C-BASS and Others
    (2015) Timbie, Peter