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The cosmic microwave background $B$-mode signal is potentially weaker than the diffuse Galactic foregrounds over most of the sky at any frequency. A common method of separating the CMB from these foregrounds is via pixel-based…

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. We have developed a new method for calculating the CMB anisotropy in…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Dmitry Pogosyan , J. Richard Bond

The geodesics followed by cosmic microwave background (CMB) photons show different behaviours depending on the geometry of space. Namely, the effect of `mixing geodesics' predicts a distinct signature in CMB maps: threshold-independent…

Astrophysics · Physics 2007-05-23 V. G. Gurzadyan , S. Torres

The CMB maps obtained by observations always possess domains which have to be masked due to severe uncertainties with respect to the genuine CMB signal. Cosmological analyses ideally use full CMB maps in order to get e.g. the angular power…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 R. Aurich , S. Lustig

Observations of microwave background fluctuations can yield information not only about the geometry of the universe, but potentially about the topology of the universe. If the universe is negatively curved, then the characteristic scale for…

Astrophysics · Physics 2009-10-30 Neil J. Cornish , David N. Spergel , Glenn D. Starkman

After the detection of structure in the microwave sky, the characterization of the observed features may be a useful guide to current and future experiments. The first year COBE-DMR sky maps were analyzed in order to identify the most…

Astrophysics · Physics 2007-05-23 S. Torres

The frequency spectrum of the cosmic microwave background (CMB) is a relatively untapped source of data which can allow us to peer beyond the surface of last scattering. Small deviations away from a perfect blackbody shape will encode…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-21 Bryce Cyr

Geometrical and statistical properties of polarization of CMB are analyzed. Singular points of the vector field which describes CMB polarization are found and classified. Statistical distribution of the singularities is studied. A possible…

Astrophysics · Physics 2009-10-31 A. Dolgov , A. Doroshkevich , D. Novikov , I. Novikov

Ongoing observations of the Cosmic Microwave Background, such as the MAXIMA and BOOMERanG projects, are providing datasets of unprecedented quality and ever-increasing size. Exact analysis of the data they produce is a serious computational…

Astrophysics · Physics 2009-10-31 Julian Borrill

We derive an optimal linear filter to suppress the noise from the COBE DMR sky maps for a given power spectrum. We then apply the filter to the first-year DMR data, after removing pixels within $20^\circ$ of the Galactic plane from the…

Astrophysics · Physics 2009-10-22 Emory F. Bunn , Karl B. Fisher , Yehuda Hoffman , Ofer Lahav , Joseph Silk , Saleem Zaroubi

Measurements of cosmic microwave background (CMB) anisotropies by interferometers offer several advantages over single-dish observations. The formalism for analyzing interferometer CMB data is well developed in the flat-sky approximation,…

Astrophysics · Physics 2008-11-26 Emory F. Bunn , Martin White

We present a method for the computation of the variance of cosmic microwave background (CMB) temperature maps on azimuthally symmetric patches using a fast convolution approach. As an example of the application of the method, we show…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-15 P. Bielewicz , B. D. Wandelt , A. J. Banday

Cosmic Microwave Background (CMB) full-sky temperature data show a hemispherical asymmetry in power nearly aligned with the Ecliptic. In real space, this anomaly can be quantified by the temperature variance in the northern and southern…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Marcio O'Dwyer , Craig J. Copi , Lloyd Knox , Glenn D. Starkman

The quest for primordial $B$-mode polarization signatures in the Cosmic Microwave Background (CMB) is a major goal of contemporary cosmology. Detecting these signatures would confirm primordial gravitational waves and allow precise…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Yusuke Takase

We apply a Wiener filter to the two-year COBE DMR data. The resulting sky map has significantly reduced noise levels compared to the raw data: the most prominent hot and cold spots are significant at the 4-sigma level. Furthermore, the…

Astrophysics · Physics 2009-10-28 Emory F. Bunn , Yehuda Hoffman , Joseph Silk

Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-13 Stephen M. Feeney , Matthew C. Johnson , Daniel J. Mortlock , Hiranya V. Peiris

The cosmic microwave background radiation allows us to measure both the geometry and topology of the universe. It has been argued that the COBE-DMR data already rule out models that are multiply connected on scales smaller than the particle…

Astrophysics · Physics 2009-10-31 Neil J. Cornish , David N. Spergel

Simulated maps of the microwave background (CMB) radiation are generally created using one of two methods: all-sky simulations use the spherical harmonic transform, while maps covering small areas approximate the sky as flat, allowing the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-22 Mariona Giner Mascarell , Emory F. Bunn

The (large angle) COBE DMR data can be used to probe the global topology of our universe on scales comparable to and just beyond the present ``horizon''. For compact topologies, the two main effects on the CMB are: [1] the breaking of…

Astrophysics · Physics 2007-05-23 J. Richard Bond , Dmitry Pogosyan , Tarun Souradeep

Broadband time-ordered data obtained from telescopes with a wavelength-dependent, asymmetric beam pattern can be used to extract maps at multiple wavelengths from a single scan. This technique is especially useful when collecting data on…

Instrumentation and Methods for Astrophysics · Physics 2023-06-06 Brianna Cantrall , Solomon Quinn , Emory F. Bunn
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