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Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

Astrophysics · Physics 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the Cosmic Microwave Background Radiation (CMBR). This instrument chops a 30\arcmin\ beam in a 3…

We study the effect of global topology of the spatial geometry on the cosmic microwave background (CMB) for closed flat and closed hyperbolic models in which the spatial hypersurface is multiply connected. If the CMB temperature…

Astrophysics · Physics 2013-09-06 Kaiki Taro Inoue

We compute the power spectrum of galaxy density fluctuations in a recently completed redshift survey of optically-selected galaxies in the southern hemisphere (SSRS2). The amplitude and shape of the SSRS2 power spectrum are consistent with…

Astrophysics · Physics 2009-10-22 L. N. da Costa , M. S. Vogeley , M. J. Geller , J. P. Huchra , C. Park

We present a Monte-Carlo technique to probe the cosmic Infrared background radiation (CIB) with faint source confusion in deep, wide-field 4 micron images. We report a detection of surface brightness fluctuations using an ensemble of 5000…

Astrophysics · Physics 2009-11-07 J. Xu , J. J. Bock , K. M. Ganga , V. Gorjian , K. Uemizu , M. Kawada , A. E. Lange , T. Matsumoto , T. Watabe

In addition to its spectrum and temperature anisotropy, the 2.7K Cosmic Microwave Background is also expected to exhibit a low level of polarization. The spatial power spectrum of the polarization can provide details about the formation of…

Astrophysics · Physics 2009-10-30 Brian Keating , Peter Timbie , Alexander Polnarev , Julia Steinberger

On large scales galaxies and their halos are usually assumed to trace the dark matter with a constant bias and dark matter is assumed to trace the linear density field. We test these assumption using several large N-body simulations with…

Astrophysics · Physics 2009-11-10 Uros Seljak , Michael S. Warren

Our motion relative to the cosmic-microwave-background (CMB) rest frame deflects light rays giving rise to shifts as large as L -> L(1+beta), where beta=0.00123 is our velocity (in units of the speed of light) on measurements CMB…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-22 Donghui Jeong , Jens Chluba , Liang Dai , Marc Kamionkowski , Xin Wang

There exist hitherto unexplained fluctuations in the Cosmic Infrared Background (CIB) on arcminute scales and larger. These have been shown to cross-correlate with the Cosmic X-ray Background (CXB), leading several authors to attribute the…

Astrophysics of Galaxies · Physics 2019-09-25 Angelo Ricarte , Fabio Pacucci , Nico Cappelluti , Priyamvada Natarajan

We present Ginga measurements of the spatial fluctuations in the diffuse X-ray background. When combined with earlier results, the new data constrain the extragalactic log N - log S relation in the 2-10 keV energy band to a form close to…

Recently, BICEP2 measurements of the cosmic microwave background (CMB) $B$-mode polarization has indicated the presence of primordial gravitational waves at degree angular scales, inferring the tensor-to-scalar ratio of $r=0.2$ and a…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Seokcheon Lee , Guo-Chin Liu , Kin-Wang Ng

We review how the various large-scale data constrain cosmological parameters and, consequently, theories for the origin of large-scale structure in the Universe. We discuss the form of the power spectrum implied by the correlation data of…

Astrophysics · Physics 2007-05-23 A. Kashlinsky

We outline a new method for estimating the cosmic infrared background using the spatial and spectral correlation properties of infrared maps. The cosmic infrared background from galaxies should have a minimum fluctuation of the order of…

Astrophysics · Physics 2015-06-24 A. Kashlinsky , J. C. Mather , S. Odenwald , M. G. Hauser

Fluctuations in the redshifted 21 centimeter emission from neutral hydrogen probe the epoch of reionization. We examine the observability of this signal and the impact of extragalactic foreground radio sources. We use cosmological…

Astrophysics · Physics 2009-11-10 Tiziana Di Matteo , Benedetta Ciardi , Francesco Miniati

We show that the cumulative CO emission from galaxies throughout cosmic history distorts the spectrum of the cosmic microwave background (CMB) at a level that is well above the detection limit of future instruments, such as the Primordial…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Natalie Mashian , Abraham Loeb , Amiel Sternberg

We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of the Universe at the time of recombination.…

Astrophysics · Physics 2014-10-13 Kris Sigurdson , Andriy Kurylov , Marc Kamionkowski

The advent of high signal-to-noise cosmic microwave background (CMB) anisotropy experiments now allow detailed studies on the statistics related to temperature fluctuations. The existence of acoustic oscillations in the anisotropy power…

Astrophysics · Physics 2007-05-23 Asantha Cooray

Measurements of 21 cm line fluctuations from minihalos have been discussed as a powerful probe of a wide range of cosmological models. However, previous studies have taken into account only the pixel variance, where contributions from…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Toyokazu Sekiguchi , Tomo Takahashi , Hiroyuki Tashiro , Shuichiro Yokoyama

We review estimates of small scale fluctuations due to extragalactic point sources in the Planck Surveyor frequency bands. While our undestanding of the spectral and evolutionary properties of these sources is far from complete,…

Astrophysics · Physics 2007-05-23 G. De Zotti , L. Toffolatti , G. L. Granato

Density inhomogeneities along the line-of-sight distort fluctuations in the cosmic microwave background. Usually, this effect is thought of as a small second-order effect that mildly alters the statistics of the microwave background…

Astrophysics · Physics 2009-10-30 Maki Suginohara , Tatsushi Suginohara , David N. Spergel
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