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Full-Text Articles in Physical Sciences and Mathematics

Systematic Effects In Interferometric Observations Of The Cosmic Microwave Background Polarization, Ata Karakci, Le Zhang, P. M. Sutter, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt Jul 2013

Systematic Effects In Interferometric Observations Of The Cosmic Microwave Background Polarization, Ata Karakci, Le Zhang, P. M. Sutter, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt

Physics Faculty Publications

The detection of the primordial B-mode spectrum of the polarized cosmic microwave background (CMB) signal may provide a probe of inflation. However, observation of such a faint signal requires excellent control of systematic errors. Interferometry proves to be a promising approach for overcoming such a challenge. In this paper we present a complete simulation pipeline of interferometric observations of CMB polarization, including systematic errors. We employ two different methods for obtaining the power spectra from mock data produced by simulated observations: the maximum likelihood method and the method of Gibbs sampling. We show that the results from both methods …


Maximum Likelihood Analysis Of Systematic Errors In Interferometric Observations Of The Cosmic Microwave Background, Le Zhang, Ata Karakci, Paul M. Sutter, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt Jun 2013

Maximum Likelihood Analysis Of Systematic Errors In Interferometric Observations Of The Cosmic Microwave Background, Le Zhang, Ata Karakci, Paul M. Sutter, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt

Physics Faculty Publications

We investigate the impact of instrumental systematic errors in interferometric measurements of the cosmic microwave background (CMB) temperature and polarization power spectra. We simulate interferometric CMB observations to generate mock visibilities and estimate power spectra using the statistically optimal maximum likelihood technique. We define a quadratic error measure to determine allowable levels of systematic error that does not induce power spectrum errors beyond a given tolerance. As an example, in this study we focus on differential pointing errors. The effects of other systematics can be simulated by this pipeline in a straightforward manner. We find that, in order to accurately …


Bayesian Inference Of Polarized Cosmic Microwave Background Power Spectra From Interferometric Data, Ata Karakci, P. M. Sutter, Le Zhang, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt Jan 2013

Bayesian Inference Of Polarized Cosmic Microwave Background Power Spectra From Interferometric Data, Ata Karakci, P. M. Sutter, Le Zhang, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt

Physics Faculty Publications

Detection of B-mode polarization of the cosmic microwave background (CMB) radiation is one of the frontiers of observational cosmology. Because they are an order of magnitude fainter than E-modes, it is quite a challenge to detect B-modes. Having more manageable systematics, interferometers prove to have a substantial advantage over imagers in detecting such faint signals. Here, we present a method for Bayesian inference of power spectra and signal reconstruction from interferometric data of the CMB polarization signal by using the technique of Gibbs sampling. We demonstrate the validity of the method in the flat-sky approximation for a simulation of an …


Interpretation Of The Arcade 2 Absolute Sky Brightness Measurement, M. Seiffert, D. J. Fixsen, A. Kogut, S. M. Levin, M. Limon, P. M. Lubin, P. Mirel, Jack Singal, T. Villela, E. Wollack, C. A. Wuensche Jun 2011

Interpretation Of The Arcade 2 Absolute Sky Brightness Measurement, M. Seiffert, D. J. Fixsen, A. Kogut, S. M. Levin, M. Limon, P. M. Lubin, P. Mirel, Jack Singal, T. Villela, E. Wollack, C. A. Wuensche

Physics Faculty Publications

We use absolutely calibrated data between 3 and 90 GHz from the 2006 balloon flight of the ARCADE 2 instrument, along with previous measurements at other frequencies, to constrain models of extragalactic emission. Such emission is a combination of the cosmic microwave background (CMB) monopole, Galactic foreground emission, the integrated contribution of radio emission from external galaxies, any spectral distortions present in the CMB, and any other extragalactic source. After removal of estimates of foreground emission from our own Galaxy, and an estimated contribution of external galaxies, we present fits to a combination of the flat-spectrum CMB and potential spectral …


Bandwidth In Bolometric Interferometry, R. Charlassier, Emory F. Bunn, J.-Ch. Hamilton, J. Kaplan, S. Malu May 2010

Bandwidth In Bolometric Interferometry, R. Charlassier, Emory F. Bunn, J.-Ch. Hamilton, J. Kaplan, S. Malu

Physics Faculty Publications

Context. Bolometric interferometry is a promising new technology with potential applications to the detection of B-mode polarization fluctuations of the cosmic microwave background (CMB). A bolometric interferometer will have to take advantage of the wide spectral detection band of its bolometers to be competitive with imaging experiments. A crucial concern is that interferometers are assumed to be significantly affected by a spoiling effect known as bandwidth smearing.

Aims. We investigate how the bandwidth modifies the work principle of a bolometric interferometer and affects its sensitivity to the CMB angular power spectra.

Methods. We obtain analytical expressions for …


Directionality In The Wilkinson Microwave Anisotropy Probe Polarization Data, D. Hanson, Douglas Scott, Emory F. Bunn Jul 2007

Directionality In The Wilkinson Microwave Anisotropy Probe Polarization Data, D. Hanson, Douglas Scott, Emory F. Bunn

Physics Faculty Publications

Polarization is the next frontier of cosmic microwave background analysis, but its signal is dominated over much of the sky by foregrounds which must be carefully removed. To determine the efficacy of this cleaning, it is necessary to have sensitive tests for residual foreground contamination in polarization sky maps. The dominant Galactic foregrounds introduce a large-scale anisotropy on to the sky, so it makes sense to use a statistic sensitive to overall directionality for this purpose. Here, we adapt the rapidly computable D statistic of Bunn and Scott to polarization data, and demonstrate its utility as a foreground monitor by …