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Sample records for microwave background cmb

  1. Task Force on Cosmic Microwave Background Research

    E-Print Network [OSTI]

    James Bock; Sarah Church; Mark Devlin; Gary Hinshaw; Andrew Lange; Adrian Lee; Lyman Page; Bruce Partridge; John Ruhl; Max Tegmark; Peter Timbie; Rainer Weiss; Bruce Winstein; Matias Zaldarriaga

    2006-04-05

    One of the most spectacular scientific breakthroughs in past decades was using measurements of the fluctuations in the cosmic microwave background (CMB) to test precisely our understanding of the history and composition of the Universe. This report presents a roadmap for leading CMB research to its logical next step, using precision polarization measurements to learn about ultra-high-energy physics and the Big Bang itself.

  2. The Polarization of the Cosmic Microwave Background

    E-Print Network [OSTI]

    Matias Zaldarriaga

    2003-05-15

    We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We discuss some physical processes that affect the CMB polarization after recombination such as gravitational lensing and the reionization of the universe.

  3. Local microwave background radiation

    E-Print Network [OSTI]

    Domingos Soares

    2014-11-13

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  4. Constraining fundamental physics with the cosmic microwave background

    E-Print Network [OSTI]

    Anthony Challinor

    2006-06-22

    The temperature anisotropies and polarization of the cosmic microwave background (CMB) radiation provide a window back to the physics of the early universe. They encode the nature of the initial fluctuations and so can reveal much about the physical mechanism that led to their generation. In this contribution we review what we have learnt so far about early-universe physics from CMB observations, and what we hope to learn with a new generation of high-sensitivity, polarization-capable instruments.

  5. SKA synergy with Microwave Background studies

    E-Print Network [OSTI]

    Burigana, Carlo; Baccigalupi, Carlo; Barbosa, Domingos; Blanchard, Alain; De Rosa, Adriano; de Zotti, Gianfranco; Finelli, Fabio; Gruppuso, Alessandro; Jones, Michael; Matarrese, Sabino; Melchiorri, Alessandro; Molinari, Diego; Negrello, Mattia; Paoletti, Daniela; Perrotta, Francesca; Scaramella, Roberto; Trombetti, Tiziana

    2015-01-01

    The extremely high sensitivity and resolution of the Square Kilometre Array (SKA) will be useful for addressing a wide set of themes relevant for cosmology, in synergy with current and future cosmic microwave background (CMB) projects. Many of these themes also have a link with future optical-IR and X-ray observations. We discuss the scientific perspectives for these goals, the instrumental requirements and the observational and data analysis approaches, and identify several topics that are important for cosmology and astrophysics at different cosmic epochs.

  6. Foreground contributions to the Cosmic Microwave Background

    E-Print Network [OSTI]

    Tadeusz Wibig; Arnold W. Wolfendale

    2005-06-21

    A detailed search has been made for evidence of foreground contributions to the Cosmic Microwave Background (CMB) WMAP, such foregrounds being related to our Galaxy. We find remarkable results. On the largest angular scales we find significant differences between the power in the fluctuations for positive and negative Galactic latitudes and between the four Galactic Quadrants. There are also differences between the power spectrum at latitudes within 10 deg of the Plane and at higher latitudes. The `slope' of the power spectrum has similar variations. In an effort to find the origin of these Galactic-style effects we have examined the evidence from Galactic gamma rays, specifically from the EGRET instrument. A correlation is found between gamma ray intensities and the CMB and other cosmic ray indicators. Most of the large scale Galactic asymmetries (eg north, south difference and Quadrant variations) have analogues in cosmic ray asymmetries and also in some other Galactic properties, such as the column density of gas. Thus, it is possible to hypothesise on direct cosmic ray-induced contributions, although it may be that cosmic rays are simply the indicators of Galactic `conditions' which are influencing the residual CMB fluctuations. Irrespective of the actual cause of the correlations we have endeavoured to extrapolate to the situation where the residual foreground is minimised. The effect on the usually-derived cosmological properties - universal matter content, ionization, the tensor contribution, tilt and curvature - is briefly examined.

  7. SPECTRUM OF THE MICROWAVE BACKGROUND RADIATION

    E-Print Network [OSTI]

    Richards, P.L.

    2010-01-01

    analysis of the data on the microwave background radiationmillimeter spec­ trum of the microwave background. Ap. J.i 0.06 Technique Averaged Microwave Reference Woo. 'y and

  8. Fractal Structure of Isothermal Lines and Loops on the Cosmic Microwave Background

    E-Print Network [OSTI]

    Chiang, Lung-Yih

    of isothermal lines and loops of the cosmic microwave background (CMB) radiation on the sky map is studied and the fractal structure is confirmed in the radiation temperature fluctuation. We estimate the fractal exponents of Hurst exponents, He for the profile of the CMB radiation temperature, and Hc for a single isothermal

  9. COSMIC MICROWAVE BACKGROUND -- PRESENT STATUS AND FUTURE PROSPECTS

    E-Print Network [OSTI]

    Muller, Richard A.

    2011-01-01

    December 14-20, 1978 COSMIC MICROWAVE BACKGROUND — PRESENTis OTUMHPSB LBL-8799 COSMIC MICROWAVE BACKGROUND ~ PRESENT> lirtLU COSMIC MICROWAVE BACKGROUND — PRESENT STATUS AND

  10. What Can the Cosmic Microwave Background Tell Us About the Outer Solar System?

    E-Print Network [OSTI]

    Daniel Babich; Cullen H. Blake; Charles Steinhardt

    2007-05-07

    We discuss two new observational techniques that use observations of the Cosmic Microwave Background (CMB) to place constraints upon the mass, distance, and size distribution of small objects in the Kuiper Belt and inner Oort Cloud, collectively known as Trans-Neptunian Objects (TNOs). The first new technique considers the spectral distortion of the isotropic, or monopole, CMB by TNOs that have been heated by solar radiation to temperatures above that of the CMB. We apply this technique to the spectral measurements of the CMB by the Far Infrared Absolute Spectrophotometer (FIRAS) on the Cosmic Background Explorer (COBE). The second technique utilizes the change in amplitude of the TNO signal due to the orbital motion of the observer to separate the TNO signal from the invariant extra-galactic CMB and construct a map of the mass distribution in the outer Solar System. We estimate the ability of future CMB experiments to create such a map.

  11. Probability Density of the Multipole Vectors for a Gaussian Cosmic Microwave Background

    E-Print Network [OSTI]

    Mark R. Dennis; Kate Land

    2007-08-09

    We review Maxwell's multipole vectors, and elucidate some of their mathematical properties, with emphasis on the application of this tool to the cosmic microwave background (CMB). In particular, for a completely random function on the sphere (corresponding to the statistically isotropic Gaussian model of the CMB), we derive the full probability density function of the multipole vectors. This function is used to analyze the internal configurations of the third-year Wilkinson Microwave Anisotropy Probe quadrupole and octopole, and we show the observations are consistent with the Gaussian prediction. A particular aspect is the planarity of the octopole, which we find not to be anomalous.

  12. NEAR-MILLIMETER SPECTRUM OF THE MICROWAVE BACKGROUND

    E-Print Network [OSTI]

    Woody, D.P.

    2013-01-01

    +o, 14 z2.06 Table 3. Microwave Measurements of the CMBMILLIMETER SPECTRUM OF THE MICROWAVE BACKGROUND D. P. WoodyMILLIMETER SPECTRUM OF THE MICROWAVE BACKGROUND D. P. Woody1

  13. Cosmic Microwave Background Project at NERSC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Challenges: Each raw observation includes contributions from instrument noise, non-CMB radiation from astronomical and terrestrial sources, and the CMB signal inself. These need...

  14. TACMB-1: The Theory of Anisotropies in the Cosmic Microwave Background (Bibliographic Resource Letter)

    E-Print Network [OSTI]

    Martin White; J. D. Cohn

    2002-03-07

    This Resource Letter provides a guide to the literature on the theory of anisotropies in the cosmic microwave background. Journal articles, web pages, and books are cited for the following topics: discovery, cosmological origin, early work, recombination, general CMB anisotropy references, primary CMB anisotropies (numerical, analytical work), secondary effects, Sunyaev-Zel'dovich effect(s), lensing, reionization, polarization, gravity waves, defects, topology, origin of fluctuations, development of fluctuations, inflation and other ties to particle physics, parameter estimation, recent constraints, web resources, foregrounds, observations and observational issues, and gaussianity.

  15. Spectral distortions in the cosmic microwave background polarization

    SciTech Connect (OSTI)

    Renaux-Petel, Sébastien [Laboratoire de Physique Théorique et Hautes Energies, Université Pierre and Marie Curie - Paris VI, CNRS-UMR 7589, 4 place Jussieu, Paris, 75252 (France); Fidler, Christian [Institute of Cosmology and Gravitation, Dennis Sciama Building, Burnaby Road, Portsmouth, PO1 3FX (United Kingdom); Pitrou, Cyril [Sorbonne Universités, Institut Lagrange de Paris, 98 bis Bd Arago, Paris, 75014 (France); Pettinari, Guido W., E-mail: srenaux@lpthe.jussieu.fr, E-mail: christian.fidler@port.ac.uk, E-mail: pitrou@iap.fr, E-mail: g.pettinari@sussex.ac.uk [Department of Physics and Astronomy, University of Sussex, Brighton, BN1 9QH (United Kingdom)

    2014-03-01

    We compute the spectral distortions of the Cosmic Microwave Background (CMB) polarization induced by non-linear effects in the Compton interactions between CMB photons and the flow of intergalactic electrons. This signal is of the y-type and is dominated by contributions arising from the reionized era. We stress that it is not shadowed by the thermal SZ effect which has no equivalent for polarization. We decompose its angular dependence into E- and B-modes, and we calculate the corresponding power spectra, both exactly and using a suitable Limber approximation that allows a simpler numerical evaluation. We find that B-modes are of the same order of magnitude as E-modes. Both spectra are relatively flat, peaking around ? = 280, and their overall amplitude is directly related to the optical depth to reionization. Moreover, we find this effect to be one order of magnitude larger than the non-linear kinetic Sunyaev-Zel'dovich effect in galaxy clusters. Finally, we discuss how to improve the detectability of our signal by cross-correlating it with other quantities sourced by the flow of intergalactic electrons.

  16. Implications about the large scale properties of the universe from the cosmic microwave background

    E-Print Network [OSTI]

    Aslanyan, Grigor; Aslanyan, Grigor

    2012-01-01

    Finding Topology with the Microwave Background Radiation,Lensing of the Cosmic Microwave Background using cross-correlations in the cosmic microwave background, Nature.

  17. Late Time Neutrino Masses, the LSND Experiment and the Cosmic Microwave Background

    E-Print Network [OSTI]

    Chacko, Z.

    2009-01-01

    Experiment and the Cosmic Microwave Background Z. Chacko,Experiment and the Cosmic Microwave Background Z. Chacko,distributions of the cosmic microwave background. arXiv:hep-

  18. Cosmological parameter estimation with QUaD CMB polarization and temperature experiment 

    E-Print Network [OSTI]

    Memari, Yasin

    2009-01-01

    In this thesis we examine the theoretical origin and statistical features of the Cosmic Microwave Background radiation. We particularly focus on the CMB power spectra and cosmological parameter estimation from QUaD CMB ...

  19. Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole

    E-Print Network [OSTI]

    Takahashi, Yuki David

    2010-01-01

    18 Microwave absorbers candidates for1.4.2 Cosmic microwave background polarization 1.4.3 Curl-Measurement of Cosmic Microwave Background Polarization

  20. The POLARBEAR Cosmic Microwave Background Polarization Experiment and Anti-Reflection Coatings for Millimeter Wave Observations

    E-Print Network [OSTI]

    Quealy, Erin

    2012-01-01

    Tables 1 The Cosmic Microwave Background as a CosmologicalFour-Year COBE DMR Cosmic Microwave Background Observations:First-Year Wilkinson Microwave Anisotropy Probe (WMAP)

  1. Noncommutative Black-Body Radiation: Implications On Cosmic Microwave Background

    E-Print Network [OSTI]

    Amir H. Fatollahi; Maryam Hajirahimi

    2006-07-12

    Including loop corrections, black-body radiation in noncommutative space is anisotropic. A direct implication of possible space noncommutativity on the Cosmic Microwave Background map is argued.

  2. Lensing-induced Non-Gaussian Signatures in the Cosmic Microwave Background

    E-Print Network [OSTI]

    Masahiro Takada

    2001-04-30

    We propose a new method for extracting the non-Gaussian signatures on the isotemperature statistics in the cosmic microwave background (CMB) sky, which is induced by the gravitational lensing due to the intervening large-scale structure of the universe. To develop the method, we focus on a specific statistical property of the intrinsic Gaussian CMB field; a field point in the map that has a larger absolute value of the temperature threshold tends to have a larger absolute value of the curvature parameter defined by a trace of second derivative matrix of the temperature field, while the ellipticity parameter similarly defined is uniformly distributed independently of the threshold because of the isotropic nature of the Gaussian field. The weak lensing then causes a stronger distortion effect on the isotemperature contours with higher threshold and especially induces a coherent distribution of the ellipticity parameter correlated with the threshold as a result of the coupling between the CMB curvature parameter and the gravitational tidal shear in the observed map. These characteristic patterns can be statistically picked up by considering three independent characteristic functions, which are obtained from the averages of quadratic combinations of the second derivative fields of CMB over isotemperature contours with each threshold. Consequently, we find that the lensing effect generates non-Gaussian signatures on those functions that have a distinct functional dependence of the threshold. We test the method using numerical simulations of CMB maps and show that the lensing signals can be measured definitely, provided that we use CMB data with sufficiently low noise and high angular resolution.

  3. Systematic effects in polarizing Fourier transform spectrometers for cosmic microwave background observations

    E-Print Network [OSTI]

    Nagler, Peter C; Kogut, Alan; Tucker, Gregory S

    2015-01-01

    The detection of the primordial B-mode polarization signal of the cosmic microwave background (CMB) would provide evidence for inflation. Yet as has become increasingly clear, the detection of a such a faint signal requires an instrument with both wide frequency coverage to reject foregrounds and excellent control over instrumental systematic effects. Using a polarizing Fourier transform spectrometer (FTS) for CMB observations meets both these requirements. In this work, we present an analysis of instrumental systematic effects in polarizing Fourier transform spectrometers, using the Primordial Inflation Explorer (PIXIE) as a worked example. We analytically solve for the most important systematic effects inherent to the FTS - emissive optical components, misaligned optical components, sampling and phase errors, and spin synchronous effects - and demonstrate that residual systematic error terms after corrections will all be at the sub-nK level, well below the predicted 100 nK B-mode signal.

  4. Hierarchical Bayesian Detection Algorithm for Early-Universe Relics in the Cosmic Microwave Background

    E-Print Network [OSTI]

    Feeney, Stephen M; McEwen, Jason D; Mortlock, Daniel J; Peiris, Hiranya V

    2013-01-01

    A number of theoretically well-motivated additions to the standard cosmological model predict weak signatures in the form of spatially localized sources embedded in the cosmic microwave background (CMB) fluctuations. We present a hierarchical Bayesian statistical formalism and a complete data analysis pipeline for testing such scenarios. We derive an accurate approximation to the full posterior probability distribution over the parameters defining any theory that predicts sources embedded in the CMB, and perform an extensive set of tests in order to establish its validity. The approximation is implemented using a modular algorithm, designed to avoid a posteriori selection effects, which combines a candidate-detection stage with a full Bayesian model-selection and parameter-estimation analysis. We apply this pipeline to theories that predict cosmic textures and bubble collisions, extending previous analyses by using: (1) adaptive-resolution techniques, allowing us to probe features of arbitrary size, and (2) o...

  5. Gravitational Lensing Effect on the Two-point Correlation of Hotspots in the Cosmic Microwave Background

    E-Print Network [OSTI]

    Masahiro Takada; Eiichiro Komatsu; Toshifumi Futamase

    2000-05-17

    We investigate the weak gravitational lensing effect due to the large-scale structure of the universe on two-point correlations of local maxima ({\\em hotspots}) in the 2D sky map of the cosmic microwave background (CMB) anisotropy. According to the Gaussian random statistics as most inflationary scenarios predict, the hotspots are discretely distributed with some {\\em characteristic} angular separations on the last scattering surface owing to oscillations of the CMB angular power spectrum. The weak lensing then causes pairs of hotspots which are separated with the characteristic scale to be observed with various separations. We found that the lensing fairly smoothes the oscillatory features of the two-point correlation function of hotspots. This indicates that the hotspots correlations can be a new statistical tool for measuring shape and normalization of the power spectrum of matter fluctuations from the lensing signatures.

  6. The Effect of Weak Gravitational Lensing on the Cosmic Microwave Background Anisotropy: Flat versus Open Universes

    E-Print Network [OSTI]

    Enrique Martinez-Gonzalez; Jose L. Sanz; Laura Cayon

    1997-02-26

    We have studied the effect of gravitational lensing on the Cosmic Microwave Background (CMB) anisotropy in flat and open universes. We develop a formalism to calculate the changes on the radiation power spectrum induced by lensing in the Newtonian and synchronous-comoving gauges. The previously considered negligible contribution to the CMB radiation power spectrum of the anisotropic term of the lensing correlation is shown to be appreciable. However, considering the nonlinear evolution of the matter power spectrum produces only slight differences on the results based on linear evolution. The general conclusion for flat as well as open universes is that lensing slightly smoothes the radiation power spectrum. For a given range of multipoles the effect of lensing increases with Omega but for the same acoustic peak it decreases with $\\Omega$. The maximum contribution of lensing to the radiation power spectrum for $l\\leq 2000$ is $\\sim$ 5% for $\\Omega$ values in the range 0.1-1.

  7. A Fast Gridded Method for the Estimation of the Power Spectrum of the CMB from Interferometer Data with Application to the Cosmic Background Imager

    E-Print Network [OSTI]

    S. T. Myers; C. R. Contaldi; J. R. Bond; U. -L. Pen; D. Pogosyan; S. Prunet; J. L. Sievers; B. S. Mason; T. J. Pearson; A. C. S. Readhead; M. C. Shepherd

    2002-05-23

    We describe an algorithm for the extraction of the angular power spectrum of an intensity field, such as the cosmic microwave background (CMB), from interferometer data. This new method, based on the gridding of interferometer visibilities in the aperture plane followed by a maximum likelihood solution for bandpowers, is much faster than direct likelihood analysis of the visibilities, and deals with foreground radio sources, multiple pointings, and differencing. The gridded aperture-plane estimators are also used to construct Wiener-filtered images using the signal and noise covariance matrices used in the likelihood analysis. Results are shown for simulated data. The method has been used to determine the power spectrum of the cosmic microwave background from observations with the Cosmic Background Imager, and the results are given in companion papers.

  8. Harmonic polynomials for expanding the fluctuations of the Cosmic Microwave Background: The Poincare and the 3-sphere model

    E-Print Network [OSTI]

    Peter Kramer

    2007-01-01

    Fluctuations of the Cosmic Microwave Background CMB are observed by the WMAP. When expanded into the harmonic eigenmodes of the space part of a cosmological model, they provide insight into the large-scale topology of space. All harmonic polynomials on the multiply connected dodecahedral Poincare space are constructed. Strong and specific selection rules are given by comparing the polynomials to those on the 3-sphere, its simply connected cover.

  9. Probing the cosmic microwave background temperature using the Sunyaev-Zeldovich effect

    E-Print Network [OSTI]

    Cathy Horellou; Martin Nord; Daniel Johansson; Anna Levy

    2005-07-01

    We discuss the possibility to constrain the relation between redshift and temperature of the cosmic microwave background (CMB) using multifrequency Sunyaev-Zeldovich (SZ) observations. We have simulated a catalog of clusters of galaxies detected through their SZ signature assuming the sensitivities that will be achieved by the {\\it Planck} satellite at 100, 143 and 353 GHz, taking into account the instrumental noise and the contamination from the Cosmic Infrared Background and from unresolved radiosources. We have parametrized the cosmological temperature-redshift law as $T\\propto (1+z)^{(1-a)}$. Using two sets of SZ flux density ratios (100/143 GHz, which is most sensitive to the parametrization of the $T-z$ law, and 143/353 GHz, which is most sensitive to the peculiar velocities of the clusters) we show that it is possible to recover the $T-z$ law assuming that the temperatures and redshifts of the clusters are known. From a simulated catalog of $\\sim 1200$ clusters, the parameter $a$ can be recovered to an accuracy of 10$^{-2}$. Sensitive SZ observations thus appear as a potentially useful tool to test the standard law. Most cosmological models predict a linear variation of the CMB temperature with redshift. The discovery of an alternative law would have profound implications on the cosmological model, implying creation of energy in a manner that would still maintain the black-body shape of the CMB spectrum at redshift zero.

  10. Radiative effects by high-z UV radiation background: Implications for the future CMB polarization measurements

    E-Print Network [OSTI]

    L. A. Popa; C. Burigana; N. Mandolesi

    2005-06-20

    We investigate the role of the radiative effects for the temporal evolution of the reionization fraction by using cosmological Smooth Particle Hydrodynamics (SPH) simulations. We find that the increase of photo-ionization and photo-heating rates due to optical depth effects results in a significantly contribute to the heating of the IGM before and during the reionization. The main effect of the UV radiation spectrum on the temporal evolution of the ionization fraction is given by the value of the reionization redshift and the redshift interval, in which the reionization is completed. We evaluate the effects of the UV radiation background on the CMB angular power spectrum taking into account different temporal evolutions of the ionization fraction. We show that through E-mode CMB polarization power spectrum measurements, the Planck experiment will have the sensitivity to distinguish between different reionization histories even when they imply the same optical depth to electron scattering and degenerated temperature anisotropy power spectra.

  11. A Measurement of Gravitational Lensing of the Cosmic Microwave Background by Galaxy Clusters Using Data from the South Pole Telescope

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baxter, E. J.; Keisler, R.; Dodelson, S.; Aird, K. A.; Allen, S. W.; Ashby, M. L.N.; Bautz, M.; Bayliss, M.; Benson, B. A.; Bleem, L. E.; et al

    2015-06-22

    Clusters of galaxies are expected to gravitationally lens the cosmic microwave background (CMB) and thereby generate a distinct signal in the CMB on arcminute scales. Measurements of this effect can be used to constrain the masses of galaxy clusters with CMB data alone. Here we present a measurement of lensing of the CMB by galaxy clusters using data from the South Pole Telescope (SPT). We also develop a maximum likelihood approach to extract the CMB cluster lensing signal and validate the method on mock data. We quantify the effects on our analysis of several potential sources of systematic error andmore »find that they generally act to reduce the best-fit cluster mass. It is estimated that this bias to lower cluster mass is roughly 0.85? in units of the statistical error bar, although this estimate should be viewed as an upper limit. Furthermore, we apply our maximum likelihood technique to 513 clusters selected via their Sunyaev–Zeldovich (SZ) signatures in SPT data, and rule out the null hypothesis of no lensing at 3.1?. The lensing-derived mass estimate for the full cluster sample is consistent with that inferred from the SZ flux: (68% C.L., statistical error only).« less

  12. Large Scale Cosmic Microwave Background Anisotropies and Dark Energy

    E-Print Network [OSTI]

    J. Weller; A. M. Lewis

    2003-08-29

    In this note we investigate the effects of perturbations in a dark energy component with a constant equation of state on large scale cosmic microwave background anisotropies. The inclusion of perturbations increases the large scale power. We investigate more speculative dark energy models with w<-1 and find the opposite behaviour. Overall the inclusion of perturbations in the dark energy component increases the degeneracies. We generalise the parameterization of the dark energy fluctuations to allow for an arbitrary const ant sound speeds and show how constraints from cosmic microwave background experiments change if this is included. Combining cosmic microwave background with large scale structure, Hubble parameter and Supernovae observations we obtain w=-1.02+-0.16 (1 sigma) as a constraint on the equation of state, which is almost independent of the sound speed chosen. With the presented analysis we find no significant constraint on the constant speed of sound of the dark energy component.

  13. A Statistic for the Detection of Long Strings in Microwave Background Maps

    E-Print Network [OSTI]

    Leandros Perivolaropoulos

    1997-04-01

    Using analytical methods and Monte Carlo simulations, we analyze a new statistic designed to detect isolated step-like discontinuities which are coherent over large areas of Cosmic Microwave Background (CMB) pixel maps. Such coherent temperature discontinuities are predicted by the Kaiser-Stebbins effect to form due to long cosmic strings present in our present horizon. The background of the coherent step-like seed is assumed to be a scale invariant Gaussian random field which could have been produced by a superposition of seeds on smaller scales and/or by inflationary quantum fluctuations. The effects of uncorrelated Gaussian random noise are also studied. The statistical variable considered is the Sample Mean Difference (SMD) between large neighbouring sectors of CMB maps, separated by a straight line in two dimensional maps and a point in one dimensional maps. We find that including noise, the SMD statistics can detect at the $1 \\sigma$ to $2 \\sigma$ level the presense of a long string with $G\\mu (v_s \\gamma_s)= 1/(8\\pi) ((\\delta T)/T)_{rms} \\simeq 0.5 \\times 10^{-7}$ while more conventional statistics like the skewness or the kurtosis require a value of $G\\mu$ almost an order of magnitude larger for detectability at a comparable level.

  14. Uniformity of Cosmic Microwave Background as a Non-Inflationary Geometrical Effect

    E-Print Network [OSTI]

    Vlahovic, Branislav; Ilie, Cosmin

    2015-01-01

    The conventional $\\Lambda$CDM cosmological model supplemented by the inflation concept describes the Universe very well. However, there are still a few concerns: new Planck data impose constraints on the shape of the inflaton potential, which exclude a lot of inflationary models; dark matter is not detected directly, and dark energy is not understood theoretically on a satisfactory level. In this brief sketch we investigate an alternative cosmological model with spherical spatial geometry and an additional perfect fluid with the constant parameter $\\omega=-1/3$ in the linear equation of state. It is demonstrated explicitly that in the framework of such a model it is possible to satisfy the supernovae data at the same level of accuracy as within the $\\Lambda$CDM model and at the same time suppose that the observed cosmic microwave background (CMB) radiation originates from a very limited space region. This is ensured by introducing an additional condition of light propagation between the antipodal points durin...

  15. Efficient Cosmological Parameter Estimation from Microwave Background Anisotropies

    E-Print Network [OSTI]

    Arthur Kosowsky; Milos Milosavljevic; Raul Jimenez

    2002-06-02

    We revisit the issue of cosmological parameter estimation in light of current and upcoming high-precision measurements of the cosmic microwave background power spectrum. Physical quantities which determine the power spectrum are reviewed, and their connection to familiar cosmological parameters is explicated. We present a set of physical parameters, analytic functions of the usual cosmological parameters, upon which the microwave background power spectrum depends linearly (or with some other simple dependence) over a wide range of parameter values. With such a set of parameters, microwave background power spectra can be estimated with high accuracy and negligible computational effort, vastly increasing the efficiency of cosmological parameter error determination. The techniques presented here allow calculation of microwave background power spectra $10^5$ times faster than comparably accurate direct codes (after precomputing a handful of power spectra). We discuss various issues of parameter estimation, including parameter degeneracies, numerical precision, mapping between physical and cosmological parameters, and systematic errors, and illustrate these considerations with an idealized model of the MAP experiment.

  16. PROBING THE EPOCH OF PRE-REIONIZATION BY CROSS-CORRELATING COSMIC MICROWAVE AND INFRARED BACKGROUND ANISOTROPIES

    SciTech Connect (OSTI)

    Atrio-Barandela, F.; Kashlinsky, A. E-mail: Alexander.Kashlinsky@nasa.gov

    2014-12-20

    The epoch of first star formation and the state of the intergalactic medium (IGM) at that time are not directly observable with current telescopes. The radiation from those early sources is now part of the cosmic infrared background (CIB) and, as these sources ionize the gas around them, the IGM plasma would produce faint temperature anisotropies in the cosmic microwave background (CMB) via the thermal Sunyaev-Zeldovich (TSZ) effect. While these TSZ anisotropies are too faint to be detected, we show that the cross-correlation of maps of source-subtracted CIB fluctuations from Euclid, with suitably constructed microwave maps at different frequencies, can probe the physical state of the gas during reionization and test/constrain models of the early CIB sources. We identify the frequency-combined, CMB-subtracted microwave maps from space- and ground-based instruments to show that they can be cross-correlated with the forthcoming all-sky Euclid CIB maps to detect the cross-power at scales ?5'-60' with signal-to-noise ratios (S/Ns) of up to S/N ? 4-8 depending on the contribution to the Thomson optical depth during those pre-reionization epochs (?? ? 0.05) and the temperature of the IGM (up to ?10{sup 4} K). Such a measurement would offer a new window to explore the emergence and physical properties of these first light sources.

  17. Lecture Notes on CMB Theory: From Nucleosynthesis to Recombination

    E-Print Network [OSTI]

    Wayne Hu

    2008-02-25

    These lecture notes comprise an informal but pedagogical introduction to the well established physics and phenomenology of the cosmic microwave background (CMB) between big bang nucleosynthesis and recombination. The dominant properties of the spectrum, temperature anisotropy and polarization anisotropy of the CMB all arise from this period. We review the physical processes involved and show how they are related to the observed phenomenology.

  18. FINGERPRINTS OF GALACTIC LOOP I ON THE COSMIC MICROWAVE BACKGROUND

    SciTech Connect (OSTI)

    Liu, Hao [Niels Bohr Institute and Discovery Center, Copenhagen University, Blegdamsvej 17, DK-2100 Copenhagen Ø (Denmark); Mertsch, Philipp [Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, M/S 29, Menlo Park, CA 94025 (United States); Sarkar, Subir, E-mail: liuhao@nbi.dk [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

    2014-07-10

    We investigate possible imprints of galactic foreground structures such as the ''radio loops'' in the derived maps of the cosmic microwave background. Surprisingly, there is evidence for these not only at radio frequencies through their synchrotron radiation, but also at microwave frequencies where emission by dust dominates. This suggests the mechanism is magnetic dipole radiation from dust grains enriched by metallic iron or ferrimagnetic molecules. This new foreground we have identified is present at high galactic latitudes, and potentially dominates over the expected B-mode polarization signal due to primordial gravitational waves from inflation.

  19. New constraints on cosmic polarization rotation from B-mode polarization in the cosmic microwave background

    SciTech Connect (OSTI)

    Alighieri, Sperello di Serego; Ni, Wei-Tou; Pan, Wei-Ping E-mail: weitou@gmail.com

    2014-09-01

    SPTpol, POLARBEAR, and BICEP2 have recently measured the cosmic microwave background (CMB) B-mode polarization in various sky regions of several tens of square degrees and obtained BB power spectra in the multipole range 20-3000, detecting the components due to gravitational lensing and to inflationary gravitational waves. We analyze jointly the results of these three experiments and propose modifications to their analyses of the spectra to include in the model, in addition to the gravitational lensing and the inflationary gravitational wave components, and also the effects induced by the cosmic polarization rotation (CPR), if it exists within current upper limits. Although in principle our analysis would also lead to new constraints on CPR, in practice these can only be given on its fluctuations (??{sup 2}), since constraints on its mean angle are inhibited by the derotation which is applied by current CMB polarization experiments, in order to cope with the insufficient calibration of the polarization angle. The combined data fits from all three experiments (with 29% CPR-SPTpol correlation, depending on the theoretical model) gives the constraint (??{sup 2}){sup 1/2} < 27.3 mrad (1.°56), with r = 0.194 ± 0.033. These results show that the present data are consistent with no CPR detection and the constraint on CPR fluctuation is about 1.°5. This method of constraining the CPR is new, is complementary to previous tests, which use the radio and optical/UV polarization of radio galaxies and the CMB E-mode polarization, and adds a new constraint for the sky areas observed by SPTpol, POLARBEAR, and BICEP2.

  20. Standard Clock in Primordial Density Perturbations and Cosmic Microwave Background

    E-Print Network [OSTI]

    Xingang Chen; Mohammad Hossein Namjoo

    2014-08-27

    Standard Clocks in the primordial epoch leave a special type of features in the primordial perturbations, which can be used to directly measure the scale factor of the primordial universe as a function of time a(t), thus discriminating between inflation and alternatives. We have started to search for such signals in the Planck 2013 data using the key predictions of the Standard Clock. In this Letter, we summarize the key predictions of the Standard Clock and present an interesting candidate example in Planck 2013 data. Motivated by this candidate, we construct and compute full Standard Clock models and use the more complete prediction to make more extensive comparison with data. Although this candidate is not yet statistically significant, we use it to illustrate how Standard Clocks appear in Cosmic Microwave Background and how they can be further tested by future data. We also use it to motivate more detailed theoretical model building.

  1. Formaldehyde Silhouettes Against the Cosmic Microwave Background: A Mass-Limited, Distance-Independent, Extinction-Free Tracer of Star Formation Across the Epoch of Galaxy Evolution

    E-Print Network [OSTI]

    Darling, Jeremy

    2012-01-01

    We examine the absorption of cosmic microwave background (CMB) photons by formaldehyde (H2CO) over cosmic time. The K-doublet rotational transitions of H2CO become "refrigerated" - their excitation temperatures are driven below the CMB temperature - via collisional pumping by molecular hydrogen (H2). "Anti-inverted" H2CO line ratios thus provide an accurate measurement of the H2 density in molecular clouds. Using a radiative transfer model, we demonstrate that H2CO centimeter wavelength line excitation and detectability are nearly independent of redshift or gas kinetic temperature. Since the H2CO K-doublet lines absorb CMB light, and since the CMB lies behind every galaxy and provides an exceptionally uniform extended illumination source, H2CO is a distance-independent, extinction-free molecular gas mass-limited tracer of dense gas in galaxies. A Formaldehyde Deep Field could map the history of cosmic star formation in a uniquely unbiased fashion and may be possible with large bandwidth wide-field radio inter...

  2. CMB probes on the correlated axion isocurvature perturbation

    E-Print Network [OSTI]

    Kenji Kadota; Jinn-Ouk Gong; Kiyotomo Ichiki; Takahiko Matsubara

    2015-01-22

    We explore the possible cosmological consequence of the gravitational coupling between the inflaton and axion-like fields. In view of the forthcoming cosmic microwave background (CMB) polarization and lensing data, we study the sensitivity of the CMB data on the cross-correlation between the curvature and axion isocurvature perturbations. Through a concrete example, we illustrate the explicit dependence of the scale dependent cross-correlation power spectrum on the axion parameters.

  3. THE WHITE MOUNTAIN POLARIMETER TELESCOPE AND AN UPPER LIMIT ON COSMIC MICROWAVE BACKGROUND POLARIZATION

    E-Print Network [OSTI]

    Timbie, Peter

    THE WHITE MOUNTAIN POLARIMETER TELESCOPE AND AN UPPER LIMIT ON COSMIC MICROWAVE BACKGROUND. Wuensche5 Received 2007 June 10; accepted 2008 March 16 ABSTRACT The White Mountain Polarimeter (WMPol microwave background. WMPol is located at an altitude of 3880 m on a plateau in the White Mountains

  4. A measurement of the cosmic microwave background B-mode polarization power spectrum at sub-degree scales with POLARBEAR

    SciTech Connect (OSTI)

    Ade, P. A. R.; Akiba, Y.; Hasegawa, M.; Anthony, A. E.; Halverson, N. W.; Arnold, K.; Atlas, M.; Barron, D.; Boettger, D.; Elleflot, T.; Feng, C.; Borrill, J.; Errard, J.; Chapman, S.; Chinone, Y.; Flanigan, D.; Dobbs, M.; Gilbert, A.; Fabbian, G.; Collaboration: Polarbear Collaboration; and others

    2014-10-20

    We report a measurement of the B-mode polarization power spectrum in the cosmic microwave background (CMB) using the POLARBEAR experiment in Chile. The faint B-mode polarization signature carries information about the universe's entire history of gravitational structure formation, and the cosmic inflation that may have occurred in the very early universe. Our measurement covers the angular multipole range 500 < ? < 2100 and is based on observations of an effective sky area of 25 deg{sup 2} with 3.'5 resolution at 150 GHz. On these angular scales, gravitational lensing of the CMB by intervening structure in the universe is expected to be the dominant source of B-mode polarization. Including both systematic and statistical uncertainties, the hypothesis of no B-mode polarization power from gravitational lensing is rejected at 97.2% confidence. The band powers are consistent with the standard cosmological model. Fitting a single lensing amplitude parameter A{sub BB} to the measured band powers, A{sub BB}=1.12±0.61(stat){sub ?0.12}{sup +0.04}(sys)±0.07(multi), where A{sub BB} = 1 is the fiducial WMAP-9 ?CDM value. In this expression, 'stat' refers to the statistical uncertainty, 'sys' to the systematic uncertainty associated with possible biases from the instrument and astrophysical foregrounds, and 'multi' to the calibration uncertainties that have a multiplicative effect on the measured amplitude A{sub BB}.

  5. Is the low-l microwave background cosmic?

    E-Print Network [OSTI]

    Dominik J. Schwarz; Glenn D. Starkman; Dragan Huterer; Craig J. Copi

    2004-11-24

    The large-angle (low-l) correlations of the Cosmic Microwave Background exhibit several statistically significant anomalies compared to the standard inflationary big-bang model, however no connection has hitherto been drawn between them. Here we show that the quadrupole and octopole are far more correlated (99.97% C.L.) than previously thought. The quadrupole plane and the three octopole planes are remarkably aligned. Three of these planes are orthogonal to the ecliptic at a level inconsistent with gaussian random statistically isotropic skies at 99.8% C.L., and the normals to these planes are aligned at 99.9% C.L. with the direction of the cosmological dipole and with the equinoxes. The remaining octopole plane is orthogonal to the supergalactic plane at >99.9% C.L. In a combined quadrupole-octopole map, the ecliptic plane narrowly threads between a hot spot and a cold spot over approximately 1/3 of the sky, and separates the three strongest extrema (in the south ecliptic hemisphere) from the three weakest extrema (in the north ecliptic hemisphere).

  6. A Flat Universe from High-Resolution Maps of the Cosmic Microwave Background Radiation

    E-Print Network [OSTI]

    P. de Bernardis; P. A. R. Ade; J. J. Bock; J. R. Bond; J. Borrill; A. Boscaleri; K. Coble; B. P. Crill; G. De Gasperis; P. C. Farese; P. G. Ferreira; K. Ganga; M. Giacometti; E. Hivon; V. V. Hristov; A. Iacoangeli; A. H. Jaffe; A. E. Lange; L. Martinis; S. Masi; P. Mason; P. D. Mauskopf; A. Melchiorri; L. Miglio; T. Montroy; C. B. Netterfield; E. Pascale; F. Piacentini; D. Pogosyan; S. Prunet; S. Rao; G. Romeo; J. E. Ruhl; F. Scaramuzzi; D. Sforna; N. Vittorio

    2000-04-28

    The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73K Cosmic Microwave Background. Tiny inhomogeneities in the early Universe left their imprint on the microwave background in the form of small anisotropies in its temperature. These anisotropies contain information about basic cosmological parameters, particularly the total energy density and curvature of the universe. Here we report the first images of resolved structure in the microwave background anisotropies over a significant part of the sky. Maps at four frequencies clearly distinguish the microwave background from foreground emission. We compute the angular power spectrum of the microwave background, and find a peak at Legendre multipole $\\ell_{peak}=(197 \\pm 6)$, with an amplitude $DT_{200}=(69 \\pm 8)\\mu K$. This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favoured by standard inflationary scenarios.

  7. SECOND SEASON QUIET OBSERVATIONS: MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRUM AT 95 GHz

    SciTech Connect (OSTI)

    Araujo, D.; Dumoulin, R. N.; Newburgh, L. B.; Zwart, J. T. L. [Department of Physics and Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A. [Kavli Institute for Cosmological Physics, Department of Physics, Enrico Fermi Institute, The University of Chicago, Chicago, IL 60637 (United States); Chinone, Y. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Cleary, K.; Reeves, R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 E. California Blvd M/C 249-17, Pasadena, CA 91125 (United States); Monsalve, R.; Bustos, R. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Naess, S. K.; Eriksen, H. K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Wehus, I. K. [Department of Astrophysics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Bronfman, L. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Church, S. E. [Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Varian Physics Building, 382 Via Pueblo Mall, Stanford, CA 94305 (United States); Dickinson, C. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Gaier, T., E-mail: ibuder@uchicago.edu [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Collaboration: QUIET Collaboration; and others

    2012-12-01

    The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95 GHz. The 43 GHz results have been published in a previous paper, and here we report the measurement of CMB polarization power spectra using the 95 GHz data. This data set comprises 5337 hr of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 {mu}K{radical}s. Four low-foreground fields were observed, covering a total of {approx}1000 deg{sup 2} with an effective angular resolution of 12.'8, allowing for constraints on primordial gravitational waves and high signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C {sub l} (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB, and BB power spectra between l = 25 and 975 and find that the EE spectrum is consistent with {Lambda}CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1{sup +0.9} {sub -0.8} (r < 2.8 at 95% C.L.) as derived by the ML pipeline, and r = 1.2{sup +0.9} {sub -0.8} (r < 2.7 at 95% C.L.) as derived by the PCL pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.

  8. Dark Energy Cosmology with the Alternative Cosmic Microwave Background Data

    E-Print Network [OSTI]

    Hao Wei

    2011-04-19

    Recently, in a series of works by Liu and Li (L&L), they claimed that there exists a timing asynchrony of $-25.6\\,$ms between the spacecraft attitude and radiometer output timestamps in the original raw WMAP time-ordered data (TOD). L&L reprocessed the WMAP data while the aforementioned timing asynchrony has been corrected, and they obtained an alternative CMB map in which the quadrupole dropped to nearly zero. In the present work, we try to see the implications to dark energy cosmology if L&L are right. While L&L claimed that there is a bug in the WMAP pipeline which leads to significantly different cosmological parameters, an interesting question naturally arises, namely, how robust is the current dark energy cosmology with respect to systematic errors and bugs? So, in this work, we adopt the alternative CMB data of L&L as a strawman to study the robustness of dark energy predictions.

  9. Making waves on CMB power spectrum and inflaton dynamics

    E-Print Network [OSTI]

    Masahiro Kawasaki; Fuminobu Takahashi; Tomo Takahashi

    2004-11-11

    We discuss cosmic microwave background anisotropies in models with an unconventional primordial power spectrum. In particular, we consider an initial power spectrum with some ``spiky'' corrections. Interestingly, such a primordial power spectrum generates ``wavy'' structure in the CMB angular power spectrum.

  10. Cosmic Microwave Background anisotropies generated by domain wall networks

    E-Print Network [OSTI]

    Sousa, L

    2015-01-01

    We develop a numerical tool for the fast computation of the temperature and polarization power spectra generated by domain wall networks, by extending the publicly available CMBACT code --- that calculates the CMB signatures generated by active sources --- to also describe domain wall networks. In order to achieve this, we adapt the Unconnected Segment model for cosmic strings to also describe domain wall networks, and use it to model the energy-momentum of domain wall networks throughout their cosmological history. We use this new tool to compute and study the TT, EE, TE and BB power spectra generated by standard domain wall networks, and derive a conservative constraint on the energy scale of the domain wall-forming phase transition of $\\upeta <0.92\\,\\,{\\rm MeV}$ (which is a slight improvement over the original Zel'dovich bound of $1\\,\\,{\\rm MeV}$).

  11. Large-Angle Anomalies in the CMB

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Copi, Craig J.; Huterer, Dragan; Schwarz, Dominik J.; Starkman, Glenn D.

    2010-01-01

    We review the recently found large-scale anomalies in the maps of temperature anisotropies in the cosmic microwave background. These include alignments of the largest modes of CMB anisotropy with each other and with geometry and direction of motion of the solar ssystem, and the unusually low power at these largest scales. We discuss these findings in relation to expectation from standard inflationary cosmology, their statistical significance, the tools to study them, and the various attempts to explain them.

  12. A measurement of the cosmic microwave background damping tail...

    Office of Scientific and Technical Information (OSTI)

    English Subject: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; BACKGROUND RADIATION; COSMOLOGICAL MODELS; COSMOLOGY; DAMPING; DATASETS; DETECTION; FLUCTUATIONS; GHZ...

  13. Constraints on cosmology from the cosmic microwave background...

    Office of Scientific and Technical Information (OSTI)

    79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; BACKGROUND RADIATION; COSMOLOGY; DETECTION; EV RANGE; FLUCTUATIONS; GALAXY CLUSTERS; HELIUM; INDEXES; LIMITING VALUES;...

  14. Polarized CMB recovery with sparse component separation

    E-Print Network [OSTI]

    Bobin, Jerome; Starck, Jean-Luc

    2015-01-01

    The polarization modes of the cosmological microwave background are an invaluable source of information for cosmology, and a unique window to probe the energy scale of inflation. Extracting such information from microwave surveys requires disentangling between foreground emissions and the cosmological signal, which boils down to solving a component separation problem. Component separation techniques have been widely studied for the recovery of CMB temperature anisotropies but quite rarely for the polarization modes. In this case, most component separation techniques make use of second-order statistics to discriminate between the various components. More recent methods, which rather emphasize on the sparsity of the components in the wavelet domain, have been shown to provide low-foreground, full-sky estimate of the CMB temperature anisotropies. Building on sparsity, the present paper introduces a new component separation technique dubbed PolGMCA (Polarized Generalized Morphological Component Analysis), which r...

  15. Inhomogeneous cosmologies, the Copernican principle and the cosmic microwave background: More on the EGS theorem

    E-Print Network [OSTI]

    C. A. Clarkson; A. A. Coley; E. S. D. O'Neill; R. A. Sussman; R. K. Barrett

    2003-02-17

    We discuss inhomogeneous cosmological models which satisfy the Copernican principle. We construct some inhomogeneous cosmological models starting from the ansatz that the all the observers in the models view an isotropic cosmic microwave background. We discuss multi-fluid models, and illustrate how more general inhomogeneous models may be derived, both in General Relativity and in scalar-tensor theories of gravity. Thus we illustrate that the cosmological principle, the assumption that the Universe we live in is spatially homogeneous, does not necessarily follow from the Copernican principle and the high isotropy of the cosmic microwave background.

  16. Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Slosar, A.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Calabrese, E.; Carlstrom, J. E.; Carvalho, C. S.; Chang, C. L.; Chiang, H. C.; Church, S.; Cooray, A.; Crawford, T. M.; Dawson, K. S.; Das, S.; Devlin, M. J.; Dobbs, M.; Dodelson, S.; Dore, O.; Dunkley, J.; Errard, J.; Fraisse, A.; Gallicchio, J.; Halverson, N. W.; Hanany, S.; Hildebrandt, S. R.; Hincks, A.; Hlozek, R.; Holder, G.; Holzapfel, W. L.; Honscheid, K.; Hu, W.; Hubmayr, J.; Irwin, K.; Jones, W. C.; Kamionkowski, M.; Keating, B.; Keisler, R.; Knox, L.; Komatsu, E.; Kovac, J.; Lawrence, C.; Lee, A. T.; Leitch, E.; Linder, E.; Lubin, P.; McMahon, J.; Miller, A.; Newburgh, L.; Niemack, M. D.; Nguyen, H.; Nguyen, H. T.; Page, L.; Pryke, C.; Reichardt, C. L.; Ruhl, J. E.; Sehgal, N.; Seljak, U.; Sievers, J.; Silverstein, E.; Smith, K. M.; Spergel, D.; Staggs, S. T.; Stark, A.; Stompor, R.; Vieregg, A. G.; Wang, G.; Watson, S.; Wollack, E. J.; Wu, W. L.K.; Yoon, K. W.; Zahn, O.; Kuo, C. -L.

    2015-03-01

    This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve ? (?mv) = 16 meV and ? (Neff)(Neff) = 0.020. Such a mass measurement will produce a high significance detection of non-zero ?m??m?, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics — the origin of mass. This precise a measurement of Neff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that Neff = 3.046.

  17. Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Abazajian, K. N.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Calabrese, E.; Carlstrom, J. E.; et al

    2014-03-15

    This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve ? (?mv) = 16 meV and ? (Neff)(Neff) = 0.020.more »Such a mass measurement will produce a high significance detection of non-zero ?m??m?, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics — the origin of mass. This precise a measurement of Neff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that Neff = 3.046.« less

  18. Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure

    SciTech Connect (OSTI)

    Abazajian, K. N.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Calabrese, E.; Carlstrom, J. E.; Carvalho, C. S.; Chang, C. L.; Chiang, H. C.; Church, S.; Cooray, A.; Crawford, T. M.; Dawson, K. S.; Das, S.; Devlin, M. J.; Dobbs, M.; Dodelson, S.; Dore, O.; Dunkley, J.; Errard, J.; Fraisse, A.; Gallicchio, J.; Halverson, N. W.; Hanany, S.; Hildebrandt, S. R.; Hincks, A.; Hlozek, R.; Holder, G.; Holzapfel, W. L.; Honscheid, K.; Hu, W.; Hubmayr, J.; Irwin, K.; Jones, W. C.; Kamionkowski, M.; Keating, B.; Keisler, R.; Knox, L.; Komatsu, E.; Kovac, J.; Kuo, C. -L.; Lawrence, C.; Lee, A. T.; Leitch, E.; Linder, E.; Lubin, P.; McMahon, J.; Miller, A.; Newburgh, L.; Niemack, M. D.; Nguyen, H.; Nguyen, H. T.; Page, L.; Pryke, C.; Reichardt, C. L.; Ruhl, J. E.; Sehgal, N.; Seljak, U.; Sievers, J.; Silverstein, E.; Slosar, A.; Smith, K. M.; Spergel, D.; Staggs, S. T.; Stark, A.; Stompor, R.; Wang, G.; Watson, S.; Wollack, E. J.; Wu, W. L.K.; Yoon, K. W.; Zahn, O.

    2014-03-15

    This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve ? (?mv) = 16 meV and ? (Neff)(Neff) = 0.020. Such a mass measurement will produce a high significance detection of non-zero ?m??m?, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics — the origin of mass. This precise a measurement of Neff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that Neff = 3.046.

  19. Loop quantum cosmology, non-Gaussianity, and CMB power asymmetry

    E-Print Network [OSTI]

    Ivan Agullo

    2015-07-16

    We argue that the anomalous power asymmetry observed in the cosmic microwave background (CMB) may have originated in a cosmic bounce preceding inflation. In loop quantum cosmology (LQC) the big bang singularity is generically replaced by a bounce due to quantum gravitational effects. We compute the spectrum of inflationary non-Gaussianity and show that strong correlation between observable scales and modes with longer (super-horizon) wavelength arise as a consequence of the evolution of perturbations across the LQC bounce. These correlations are strongly scale dependent and induce a dipole-dominated modulation on large angular scales in the CMB, in agreement with observations.

  20. Loop quantum cosmology, non-Gaussianity, and CMB power asymmetry

    E-Print Network [OSTI]

    Agullo, Ivan

    2015-01-01

    We argue that the anomalous power asymmetry observed in the cosmic microwave background (CMB) may have originated in a cosmic bounce preceding inflation. In loop quantum cosmology (LQC) the big bang singularity is generically replaced by a bounce due to quantum gravitational effects. We compute the spectrum of inflationary non-Gaussianity and show that strong correlation between observable scales and modes with longer (super-horizon) wavelength arise as a consequence of the evolution of perturbations across the LQC bounce. These correlations are strongly scale dependent and induce a dipole-dominated modulation on large angular scales in the CMB, in agreement with observations.

  1. Small-scale primordial magnetic fields and anisotropies in the cosmic microwave background radiation

    SciTech Connect (OSTI)

    Jedamzik, Karsten [Laboratoire de Univers et Particules, UMR5299-CNRS, Université de Montpellier II, F-34095 Montpellier (France); Abel, Tom, E-mail: karsten.jedamzik@um2.fr, E-mail: tabel@slac.stanford.edu [Kavli Institute for Particle Astrophysics and Cosmology, SLAC/Stanford University, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2013-10-01

    It is shown that small-scale magnetic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the Universe, which in turn decreases the angular scale of the Doppler peaks and increases Silk damping by photon diffusion. This unique signature could be used to (dis)prove the existence of primordial magnetic fields of strength as small as B ? 10{sup ?11} Gauss by cosmic microwave background observations.

  2. Maximum entropy method for reconstruction of the CMB images

    E-Print Network [OSTI]

    A. T. Bajkova

    2002-05-21

    We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into account {\\it a priori} information about finiteness and spherical symmetry of the power spectrum of the CMB satisfying the Gaussian statistics.

  3. Cosmic IR Backgrounds Ned Wright (UCLA)

    E-Print Network [OSTI]

    Wright, Edward L. "Ned"

    ://sirtf.caltech.edu #12;Definitions #12;Wide window on the CBR #12;Backgrounds · Microwave ­ the CMB is 10,000 times;Expanding Mirrored Box #12;Ell-to-energy #12;dX-to-energy #12;time-redshift #12;Luminosity density vs to the Sun, the most luminous galaxies in the Universe, and also map the large- scale structure out

  4. Which Fundamental Constants for CMB and BAO?

    E-Print Network [OSTI]

    Rich, James

    2015-01-01

    We study the Cosmic Microwave Background using the three-scale framework of Hu et al. to derive the dependence of the CMB temperature anisotropy spectrum on the fundamental constants. We show that, as expected, the observed spectrum depends only on \\emph{dimensionless} combinations of the constants, and we emphasize the points that make this generally true for cosmological observations. Our analysis suggests that the CMB spectrum shape is mostly determined by $\\alpha^2m_e/m_p$ and the proton-CDM-particle mass ratio, $m_p/\\mchi$, with a sub-dominant dependence on $(G\\mchi m_e/\\hbar c)\\alpha^\\beta$ with $\\beta\\sim -7$. The distance to the last-scattering surface depends on $Gm_p\\mchi/\\hbar c$, so published CMB observational limits on time variations of the constants, besides making assumptions about the form of the dark-energy, implicitly assume the time-independence of this quantity. On the other hand, low-redshift $H_0$, BAO and large-scale structure data can be combined with the \\emph{shape} of the CMB spect...

  5. Testing the CMB Data for Systematic Effects

    E-Print Network [OSTI]

    Griffiths, L M; Griffiths, Louise M.; Lineweaver, Charles H.

    2004-01-01

    Under the assumption that the concordance Lambda-cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with respect to this model. Residuals are analysed as a function of angular scale l, galactic latitude, frequency, calibration source, instrument type and several other variables that may be associated with potential systematic effects. Our main result is that we find no significant systematic errors associated with these variables. However, we do find marginal evidence for a trend associated with galactic latitude indicative of galactic contamination.

  6. Phases of New Physics in the CMB

    E-Print Network [OSTI]

    Daniel Baumann; Daniel Green; Joel Meyers; Benjamin Wallisch

    2015-08-26

    Fluctuations in the cosmic neutrino background are known to produce a phase shift in the acoustic peaks of the cosmic microwave background. It is through the sensitivity to this effect that the recent CMB data has provided a robust detection of free-streaming neutrinos. In this paper, we revisit the phase shift of the CMB anisotropy spectrum as a probe of new physics. The phase shift is particularly interesting because its physical origin is strongly constrained by the analytic properties of the Green's function of the gravitational potential. For adiabatic fluctuations, a phase shift requires modes that propagate faster than the speed of fluctuations in the photon-baryon plasma. This possibility is realized by free-streaming relativistic particles, such as neutrinos or other forms of dark radiation. Alternatively, a phase shift can arise from isocurvature fluctuations. We present simple models to illustrate each of these effects. We then provide observational constraints from the Planck temperature and polarization data on additional forms of radiation. We also forecast the capabilities of future CMB Stage IV experiments. Whenever possible, we give analytic interpretations of our results.

  7. Matrix Filters for the Detection of Extragalactic Point Sources in Cosmic Microwave Background Images

    E-Print Network [OSTI]

    D. Herranz; J. L. Sanz

    2008-08-03

    In this paper we introduce a new linear filtering technique, the so-called matrix filters, that maximizes the signal-to-interference ratio of compact sources of unknown intensity embedded in a set of images by taking into account the cross-correlations between the different channels. By construction, the new filtering technique outperforms (or at least equals) the standard matched filter applied on individual images. An immediate application is the detection of extragalactic point sources in Cosmic Microwave Background images obtained at different wavelengths. We test the new technique in two simulated cases: a simple two-channel case with ideal correlated color noise and more realistic simulations of the sky as it will be observed by the LFI instrument of the upcoming ESA's Planck mission. In both cases we observe an improvement with respect to the standard matched filter in terms of signal-to-noise interference, number of detections and number of false alarms.

  8. A guide to designing future ground-based cosmic microwave background experiments

    SciTech Connect (OSTI)

    Wu, W. L. K.; Kuo, C. L.; Errard, J.; Dvorkin, C.; Lee, A. T.; McDonald, P.; Zahn, O.; Slosar, A.

    2014-06-20

    In this follow-up work to the high energy physics Community Summer Study 2013 (aka SNOWMASS), we explore the scientific capabilities of a future Stage IV cosmic microwave background polarization experiment under various assumptions on detector count, resolution, and sky coverage. We use the Fisher matrix technique to calculate the expected uncertainties of cosmological parameters in ??CDM that are especially relevant to the physics of fundamental interactions, including neutrino masses, effective number of relativistic species, dark energy equation of state, dark matter annihilation, and inflationary parameters. To further chart the landscape of future cosmology probes, we include forecasted results from the baryon acoustic oscillation signal as measured by Dark Energy Spectroscopic Instrument to constrain parameters that would benefit from low redshift information. We find the following best 1? constraints: ?(M {sub ?}) = 15 meV, ?(N {sub eff}) = 0.0156, dark energy figure of merit = 303, ?(p {sub ann}) = 0.00588 × 3 × 10{sup –26} cm{sup 3} s{sup –1} GeV{sup –1}, ?(? {sub K}) = 0.00074, ?(n{sub s} ) = 0.00110, ?(? {sub s}) = 0.00145, and ?(r) = 0.00009. We also detail the dependencies of the parameter constraints on detector count, resolution, and sky coverage.

  9. Level Crossing Analysis of Cosmic Microwave Background Radiation: A method for detecting cosmic strings

    E-Print Network [OSTI]

    M. Sadegh Movahed; Shahram Khosravi

    2011-03-01

    In this paper we study the footprint of cosmic string as the topological defects in the very early universe on the cosmic microwave background radiation. We develop the method of level crossing analysis in the context of the well-known Kaiser-Stebbins phenomenon for exploring the signature of cosmic strings. We simulate a Gaussian map by using the best fit parameter given by WMAP-7 and then superimpose cosmic strings effects on it as an incoherent and active fluctuations. In order to investigate the capability of our method to detect the cosmic strings for the various values of tension, $G\\mu$, a simulated pure Gaussian map is compared with that of including cosmic strings. Based on the level crossing analysis, the superimposed cosmic string with $G\\mu\\gtrsim 4\\times 10^{-9}$ in the simulated map without instrumental noise and the resolution $R=1'$ could be detected. In the presence of anticipated instrumental noise the lower bound increases just up to $G\\mu\\gtrsim 5.8\\times 10^{-9}$.

  10. Degree-scale cosmic microwave background polarization measurements from three years of BICEP1 data

    SciTech Connect (OSTI)

    Barkats, D. [Joint ALMA Observatory, ESO, Santiago (Chile); Aikin, R.; Bock, J. J.; Filippini, J.; Hristov, V. V. [Department of Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Bischoff, C.; Buder, I.; Kovac, J. M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 42, Cambridge, MA 02138 (United States); Kaufman, J. P.; Keating, B. G.; Bierman, E. M. [Department of Physics, University of California at San Diego, La Jolla, CA 92093 (United States); Su, M. [Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Ade, P. A. R. [Department of Physics and Astronomy, University of Wales, Cardiff, CF24 3YB Wales (United Kingdom); Battle, J. O.; Dowell, C. D. [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Chiang, H. C. [Astrophysics and Cosmology Research Unit, University of KwaZulu-Natal, Durban (South Africa); Duband, L. [SBT, Commissariat à l'Energie Atomique, Grenoble F-38041 (France); Hivon, E. F. [Institut d'Astrophysique de Paris, Paris (France); Holzapfel, W. L. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720 (United States); Jones, W. C., E-mail: dbarkats@alma.cl [Department of Physics, Princeton University, Princeton, NJ 08544 (United States); and others

    2014-03-10

    BICEP1 is a millimeter-wavelength telescope designed specifically to measure the inflationary B-mode polarization of the cosmic microwave background at degree angular scales. We present results from an analysis of the data acquired during three seasons of observations at the South Pole (2006-2008). This work extends the two-year result published in Chiang et al., with additional data from the third season and relaxed detector-selection criteria. This analysis also introduces a more comprehensive estimation of band power window functions, improved likelihood estimation methods, and a new technique for deprojecting monopole temperature-to-polarization leakage that reduces this class of systematic uncertainty to a negligible level. We present maps of temperature, E- and B-mode polarization, and their associated angular power spectra. The improvement in the map noise level and polarization spectra error bars are consistent with the 52% increase in integration time relative to Chiang et al. We confirm both self-consistency of the polarization data and consistency with the two-year results. We measure the angular power spectra at 21 ? ? ? 335 and find that the EE spectrum is consistent with Lambda cold dark matter cosmology, with the first acoustic peak of the EE spectrum now detected at 15?. The BB spectrum remains consistent with zero. From B-modes only, we constrain the tensor-to-scalar ratio to r=0.03{sub ?0.23}{sup +0.27}, or r < 0.70 at 95% confidence level.

  11. Design of Dual-Polarization Horn-Coupled Kinetic Inductance Detectors for Cosmic Microwave Background Polarimetry

    E-Print Network [OSTI]

    Bryan, Sean; Che, George; Day, Peter; Flanigan, Daniel; Johnson, Bradley R; Jones, Glenn; Kjellstrand, Bjorn; Limon, Michele; Mauskopf, Philip; McCarrick, Heather; Miller, Amber; Smiley, Brian

    2015-01-01

    Mapping the polarization of the Cosmic Microwave Background is yielding exciting data on the origin of the universe, the reionization of the universe, and the growth of cosmic structure. Kilopixel arrays represent the current state of the art, but advances in detector technology are needed to enable the larger detector arrays needed for future measurements. Here we present a design for single-band dual-polarization Kinetic Inductance Detectors (KIDs) at 20% bandwidths centered at 145, 220, and 280 GHz. The detection and readout system is nearly identical to the successful photon-noise-limited aluminum Lumped-Element KIDs that have been recently built and tested by some of the authors. Fabricating large focal plane arrays of the feed horns and quarter-wave backshorts requires only conventional precision machining. Since the detectors and readout lines consist only of a single patterned aluminum layer on a SOI wafer, arrays of the detectors can be built commercially or at a standard university cleanroom.

  12. FIRST SEASON QUIET OBSERVATIONS: MEASUREMENTS OF COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRA AT 43 GHz IN THE MULTIPOLE RANGE 25 {<=} l {<=} 475

    SciTech Connect (OSTI)

    Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A.; Smith, K. M. [Kavli Institute for Cosmological Physics, Department of Physics, Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Chinone, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Cleary, K.; Reeves, R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Dumoulin, R. N.; Newburgh, L. B.; Zwart, J. T. L. [Department of Physics and Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Monsalve, R.; Bustos, R. [Department of Physics, University of Miami, Coral Gables, FL 33146 (United States); Naess, S. K.; Eriksen, H. K. [Institute of Theoretical Astrophysics, University of Oslo, N-0315 Oslo (Norway); Wehus, I. K. [Department of Physics, University of Oslo, N-0316 Oslo (Norway); Zuntz, J. A. [Department of Astrophysics, University of Oxford, Oxford OX1 3RH (United Kingdom); Bronfman, L. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Church, S. E. [Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Varian Physics Building, Stanford, CA 94305 (United States); Dickinson, C., E-mail: akito@kicp.uchicago.edu [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom)

    2011-11-10

    The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43 GHz and 94 GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to measure the anisotropy in the polarization of the cosmic microwave background (CMB). QUIET primarily targets the B modes from primordial gravitational waves. The combination of these frequencies gives sensitivity to foreground contributions from diffuse Galactic synchrotron radiation. Between 2008 October and 2010 December, over 10,000 hr of data were collected, first with the 19 element 43 GHz array (3458 hr) and then with the 90 element 94 GHz array. Each array observes the same four fields, selected for low foregrounds, together covering Almost-Equal-To 1000 deg{sup 2}. This paper reports initial results from the 43 GHz receiver, which has an array sensitivity to CMB fluctuations of 69 {mu}K{radical}s. The data were extensively studied with a large suite of null tests before the power spectra, determined with two independent pipelines, were examined. Analysis choices, including data selection, were modified until the null tests passed. Cross-correlating maps with different telescope pointings is used to eliminate a bias. This paper reports the EE, BB, and EB power spectra in the multipole range l = 25-475. With the exception of the lowest multipole bin for one of the fields, where a polarized foreground, consistent with Galactic synchrotron radiation, is detected with 3{sigma} significance, the E-mode spectrum is consistent with the {Lambda}CDM model, confirming the only previous detection of the first acoustic peak. The B-mode spectrum is consistent with zero, leading to a measurement of the tensor-to-scalar ratio of r = 0.35{sup +1.06}{sub -0.87}. The combination of a new time-stream 'double-demodulation' technique, side-fed Dragonian optics, natural sky rotation, and frequent boresight rotation leads to the lowest level of systematic contamination in the B-mode power so far reported, below the level of r = 0.1.

  13. Punctuated inflation and the low CMB multipoles

    SciTech Connect (OSTI)

    Jain, Rajeev Kumar; Sriramkumar, L. [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India)] [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Chingangbam, Pravabati [Korea Institute for Advanced Study, 207-43 Cheongnyangni 2-dong, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of)] [Korea Institute for Advanced Study, 207-43 Cheongnyangni 2-dong, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of); Gong, Jinn-Ouk [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706-1390 (United States)] [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706-1390 (United States); Souradeep, Tarun, E-mail: rajeev@hri.res.in, E-mail: prava@kias.re.kr, E-mail: jgong@hep.wisc.edu, E-mail: sriram@hri.res.in, E-mail: tarun@iucaa.ernet.in [IUCAA, Post Bag 4, Ganeshkhind, Pune 411 007 (India)] [IUCAA, Post Bag 4, Ganeshkhind, Pune 411 007 (India)

    2009-01-15

    We investigate inflationary scenarios driven by a class of potentials which are similar in form to those that arise in certain minimal supersymmetric extensions of the standard model. We find that these potentials allow a brief period of departure from inflation sandwiched between two stages of slow roll inflation. We show that such a background behavior leads to a step like feature in the scalar power spectrum. We set the scales such that the drop in the power spectrum occurs at a length scale that corresponds to the Hubble radius today - a feature that seems necessary to explain the lower power observed in the quadrupole moment of the Cosmic Microwave Background (CMB) anisotropies. We perform a Markov Chain Monte Carlo analysis to determine the values of the model parameters that provide the best fit to the recent WMAP 5-year data for the CMB angular power spectrum. We find that an inflationary spectrum with a suppression of power at large scales that we obtain leads to a much better fit (with just one extra parameter, {chi}{sub eff}{sup 2} improves by 6.62) of the observed data when compared to the best fit reference {Lambda}CDM model with a featureless, power law, primordial spectrum.

  14. Probing a panoply of curvaton-decay scenarios using CMB data

    E-Print Network [OSTI]

    Tristan L. Smith; Daniel Grin

    2015-11-23

    In the curvaton scenario, primordial curvature perturbations are produced by a second field that is sub-dominant during inflation. Depending on how the curvaton decays [possibly producing baryon number, lepton number, or cold dark matter (CDM)], mixtures of correlated isocurvature perturbations are produced, allowing the curvaton scenario to be tested using cosmic microwave background (CMB) data. Here, a full range of 27 curvaton-decay scenarios is compared with CMB data, placing limits on the curvaton fraction at decay, $r_D$, and the lepton asymmetry, $\\xi_{\\rm lep}$. If baryon number is generated by curvaton decay and CDM before (or vice-versa), these limits imply specific predictions for non-Gaussian signatures testable by future CMB experiments and upcoming large-scale-structure surveys.

  15. CMB constraints on the fine structure constant

    E-Print Network [OSTI]

    Kazuhide Ichikawa; Toru Kanzaki; Masahiro Kawasaki

    2006-05-25

    We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We obtain the constraints -0.097 < Delta alpha/alpha < 0.034 at 95% C.L. using WMAP data only, and -0.042 < Delta alpha/alpha < 0.026 combining with the constraint on the Hubble parameter by the HST Hubble Key Project. These are improved by 15% compared with constraints assuming only alpha varies. We discuss other relations between variations in alpha and m_e but we do not find evidence for varying alpha.

  16. On the detection of point sources in Planck LFI 70 GHz CMB maps based on cleaned K-map

    E-Print Network [OSTI]

    Khachatryan, H G; Poghosyan, E; Yegoryan, G

    2015-01-01

    We use the Planck LFI 70GHz data to further probe point source detection technique in the sky maps of the cosmic microwave background (CMB) radiation. The method developed by Tegmark et al. for foreground reduced maps and the Kolmogorov parameter as the descriptor are adopted for the analysis of Planck satellite CMB temperature data. Most of the detected points coincide with point sources already revealed by other methods. However, we have also found 9 source candidates for which still no counterparts are known.

  17. Signatures of anisotropic sources in the trispectrum of the cosmic microwave background

    SciTech Connect (OSTI)

    Shiraishi, Maresuke; Komatsu, Eiichiro; Peloso, Marco E-mail: komatsu@mpa-garching.mpg.de

    2014-04-01

    Soft limits of N-point correlation functions, in which one wavenumber is much smaller than the others, play a special role in constraining the physics of inflation. Anisotropic sources such as a vector field during inflation generate distinct angular dependence in all these correlators, and introduce a fix privileged direction in our sky. In this paper we focus on the four-point correlator (the trispectrum T). We adopt a parametrization motivated by models in which the inflaton ? is coupled to a vector field through a I{sup 2}(?)F{sup 2} interaction, namely T{sub ?}(k{sub 1},k{sub 2},k{sub 3},k{sub 4})??{sub n}d{sub n}[P{sub n}( k-circumflex {sub 1}? k-circumflex {sub 3})+P{sub n}( k-circumflex {sub 1}? k-circumflex {sub 12})+P{sub n}( k-circumflex {sub 3}? k-circumflex {sub 12})]P{sub ?}(k{sub 1})P{sub ?}(k{sub 3})P{sub ?}(k{sub 12})+(23perm), where P{sub n} denotes the Legendre polynomials. This shape is enhanced when the wavenumbers of the diagonals of the quadrilateral are much smaller than the sides, k{sub i}. The coefficient of the isotropic part, d{sub 0}, is equal to ?{sub NL}/6 discussed in the literature. A I{sup 2}(?)F{sup 2} interaction generates d{sub 2} = 2d{sub 0} which is, in turn, related to the quadrupole modulation parameter of the power spectrum, g{sub *}, as d{sub 2} ? 14|g{sub *}|N{sup 2} with N ? 60. We show that d{sub 0} and d{sub 2} can be equally well-constrained: the expected 68% CL error bars on these coefficients from a cosmic-variance-limited experiment measuring temperature anisotropy of the cosmic microwave background up to ?{sub max} = 2000 are ?d{sub 2} ? 4?d{sub 0} = 105. Therefore, we can reach |g{sub *}| = 10{sup ?3} by measuring the angle-dependent trispectrum. The current upper limit on ?{sub NL} from the Planck temperature maps yields |g{sub *}| < 0.02 (95% CL)

  18. An Efficient Technique for making maps from Observations of the Cosmic Microwave Background Radiation

    E-Print Network [OSTI]

    L. Piccirillo; G. Romeo; R. K. Schaefer; M. Limon

    1996-08-12

    We describe a new technique for turning scans of the microwave sky into intensity maps. The technique is based on a Fourier series analysis and is inspired by the lock-in deconvolution used in experiments which typically sweep the sky continuously. We test the technique on computer generated microwave skies and compare it to the more standard map making technique based on linear algebra. We find that our technique is much faster than the usual technique and, in addition, does not suffer from the problem of memory limitations. Lastly we demonstrate that the technique works under real experimental conditions using observations of the moon.

  19. CMB ISW-lensing bispectrum from cosmic strings

    SciTech Connect (OSTI)

    Yamauchi, Daisuke; Sendouda, Yuuiti; Takahashi, Keitaro E-mail: sendouda@cc.hirosaki-u.ac.jp

    2014-02-01

    We study the effect of weak lensing by cosmic (super-)strings on the higher-order statistics of the cosmic microwave background (CMB). A cosmic string segment is expected to cause weak lensing as well as an integrated Sachs-Wolfe (ISW) effect, the so-called Gott-Kaiser-Stebbins (GKS) effect, to the CMB temperature fluctuation, which are thus naturally cross-correlated. We point out that, in the presence of such a correlation, yet another kind of the post-recombination CMB temperature bispectra, the ISW-lensing bispectra, will arise in the form of products of the auto- and cross-power spectra. We first present an analytic method to calculate the autocorrelation of the temperature fluctuations induced by the strings, and the cross-correlation between the temperature fluctuation and the lensing potential both due to the string network. In our formulation, the evolution of the string network is assumed to be characterized by the simple analytic model, the velocity-dependent one scale model, and the intercommutation probability is properly incorporated in order to characterize the possible superstringy nature. Furthermore, the obtained power spectra are dominated by the Poisson-distributed string segments, whose correlations are assumed to satisfy the simple relations. We then estimate the signal-to-noise ratios of the string-induced ISW-lensing bispectra and discuss the detectability of such CMB signals from the cosmic string network. It is found that in the case of the smaller string tension, G? << 10{sup -7}, the ISW-lensing bispectrum induced by a cosmic string network can constrain the string-model parameters even more tightly than the purely GKS-induced bispectrum in the ongoing and future CMB observations on small scales.

  20. Background

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tech Transfer Success Stories * 2010 Background Renewable energy sources are critical to the nation's future, and hydrogen-powered fuel cells offer an attractive alternative to...

  1. Background

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0 Background Highway construction workers, airport maintenance personnel, and film crews use small, portable lighting systems known as "mobile lighting." Traditionally, mobile...

  2. Scalar potential model of the CMB radiation temperature

    E-Print Network [OSTI]

    John C. Hodge

    2006-03-06

    A derivation of a theoretical, time average, cosmic microwave background (CMB), Planckian temperature V of the universe remains a challenge. A scalar potential model (SPM) that resulted from considerations of galaxy cells is applied to deriving a value for V. The heat equation is solved for a cell with the boundary conditions of SPM Source and Sink characteristics, with simplified cell characteristics, and with zero initial temperature. The universe is a collection of cells. The CMB radiation is black body radiation with the cells acting as radiators and absorbers. Conventional thermodynamics is applied to calculate V = 2.718 K. The temperature and matter content of cells are finely controlled by a feedback mechanism. Because time is required for matter to flow from Sources to Sinks, the radiation temperature of cells cycles about V after an initial growth phase. If the universe is like an ideal gas in free expansion and is not in thermal equilibrium, then the pressure and volume follow the measured CMB temperature vm = 2.725 K. Therefore, increasing vm >V equates to an expansion pressure on matter and expanding volume.

  3. Searching for primordial non-Gaussianity in Planck CMB maps using a combined estimator

    SciTech Connect (OSTI)

    Novaes, C.P.; Wuensche, C.A. [Divisão de Astrofísica, Instituto Nacional de Pesquisas Espaciais, Av. dos Astronautas 1758, São José dos Campos 12227-010, SP (Brazil); Bernui, A. [Observatório Nacional, Rua General José Cristino 77, São Cristóvão, 20921-400, Rio de Janeiro, RJ (Brazil); Ferreira, I.S., E-mail: camilapnovaes@gmail.com, E-mail: bernui@on.br, E-mail: ivan@fis.unb.br, E-mail: ca.wuensche@inpe.br [Instituto de Física, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Asa Norte, 70919-970, Brasília, DF (Brazil)

    2014-01-01

    The extensive search for deviations from Gaussianity in cosmic microwave background radiation (CMB) data is very important due to the information about the very early moments of the universe encoded there. Recent analyses from Planck CMB data do not exclude the presence of non-Gaussianity of small amplitude, although they are consistent with the Gaussian hypothesis. The use of different techniques is essential to provide information about types and amplitudes of non-Gaussianities in the CMB data. In particular, we find interesting to construct an estimator based upon the combination of two powerful statistical tools that appears to be sensitive enough to detect tiny deviations from Gaussianity in CMB maps. This estimator combines the Minkowski functionals with a Neural Network, maximizing a tool widely used to study non-Gaussian signals with a reinforcement of another tool designed to identify patterns in a data set. We test our estimator by analyzing simulated CMB maps contaminated with different amounts of local primordial non-Gaussianity quantified by the dimensionless parameter f{sub  NL}. We apply it to these sets of CMB maps and find ?> 98% of chance of positive detection, even for small intensity local non-Gaussianity like f{sub  NL} = 38±18, the current limit from Planck data for large angular scales. Additionally, we test the suitability to distinguish between primary and secondary non-Gaussianities: first we train the Neural Network with two sets, one of nearly Gaussian CMB maps (|f{sub  NL}| ? 10) but contaminated with realistic inhomogeneous Planck noise (i.e., secondary non-Gaussianity) and the other of non-Gaussian CMB maps, that is, maps endowed with weak primordial non-Gaussianity (28 ? f{sub  NL} ? 48); after that we test an ensemble composed of CMB maps either with one of these non-Gaussian contaminations, and find out that our method successfully classifies ? 95% of the tested maps as being CMB maps containing primordial or secondary non-Gaussianity. Furthermore, we analyze the foreground-cleaned Planck maps obtaining constraints for non-Gaussianity at large-angles that are in good agreement with recent constraints. Finally, we also test the robustness of our estimator including cut-sky masks and realistic noise maps measured by Planck, obtaining successful results as well.

  4. Determining the motion of the solar system relative to the cosmic microwave background using type Ia supernovae

    E-Print Network [OSTI]

    Christopher Gordon; Kate Land; Anze Slosar

    2008-04-04

    We estimate the solar system motion relative to the cosmic microwave background using type Ia supernovae (SNe) measurements. We take into account the correlations in the error bars of the SNe measurements arising from correlated peculiar velocities. Without accounting for correlations in the peculiar velocities, the SNe data we use appear to detect the peculiar velocity of the solar system at about the 3.5 sigma level. However, when the correlations are correctly accounted for, the SNe data only detects the solar system peculiar velocity at about the 2.5 sigma level. We forecast that the solar system peculiar velocity will be detected at the 9 sigma level by GAIA and the 11 sigma level by the LSST. For these surveys we find the correlations are much less important as most of the signal comes from higher redshifts where the number density of SNe is insufficient for the correlations to be important.

  5. Oxygen Pumping: Mapping the Reionization Epoch with the CMB

    E-Print Network [OSTI]

    Carlos Hernandez-Monteagudo; Zoltan Haiman; Raul Jimenez; Licia Verde

    2006-12-14

    We consider the pumping of the $63.2 \\mu$m fine structure line of neutral OI in the high--redshift intergalactic medium (IGM), in analogy with the Wouthuysen--Field effect for the 21cm line of cosmic HI. We show that the soft UV background at $\\sim 1300$\\AA can affect the population levels, and if a significant fraction of the IGM volume is filled with ``fossil HII regions'' containing neutral OI, then this can produce a non--negligible spectral distortion in the cosmic microwave background (CMB). OI from redshift $z$ is seen in emission at $(1+z)63.2\\mu$m, and between $7CMB with a $y$--parameter of $y=(10^{-9} - 3\\times10^{-8}) (Z/10^{-3}{\\rm Z_{\\odot}}) (I_{UV})$, where $Z$ is the mean metallicity of the IGM and $I_{UV}$ is the UV background at 1300\\AA in units of $10^{-20}$ erg/s/Hz/cm$^2$/sr. Because O is in charge exchange equilibrium with H, a measurement of this signature can trace the metallicity at the end of the dark ages, prior to the completion of cosmic reionization and is complementary to cosmological 21cm studies. While future CMB experiments, such as Planck could constrain the metallicity to the $10^{-2} Z_{\\odot}$ level, specifically designed experiments could potentially achieve a detection. Fluctuations of the distortion on small angular scale may also be detectable.

  6. Atmospheric contamination for CMB ground-based observations

    E-Print Network [OSTI]

    Errard, J; Akiba, Y; Arnold, K; Atlas, M; Baccigalupi, C; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Cukierman, A; Delabrouille, J; Dobbs, M; Ducout, A; Elleflot, T; Fabbian, G; Feng, C; Feeney, S; Gilbert, A; Goeckner-Wald, N; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Hill, C; Holzapfel, W L; Hori, Y; Inoue, Y; Jaehnig, G C; Jaffe, A H; Jeong, O; Katayama, N; Kaufman, J; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Jeune, M Le; Lee, A T; Leitch, E M; Leon, D; Linder, E; Matsuda, F; Matsumura, T; Miller, N J; Myers, M J; Navaroli, M; Nishino, H; Okamura, T; Paar, H; Peloton, J; Poletti, D; Puglisi, G; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Rotermund, K M; Schenck, D E; Sherwin, B D; Siritanasak, P; Smecher, G; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Tajima, O; Takakura, S; Tikhomirov, A; Tomaru, T; Whitehorn, N; Wilson, B; Yadav, A; Zahn, O

    2015-01-01

    Atmosphere is one of the most important noise sources for ground-based Cosmic Microwave Background (CMB) experiments. By increasing optical loading on the detectors, it amplifies their effective noise, while its fluctuations introduce spatial and temporal correlations between detected signals. We present a physically motivated 3d-model of the atmosphere total intensity emission in the millimeter and sub-millimeter wavelengths. We derive an analytical estimate for the correlation between detectors time-ordered data as a function of the instrument and survey design, as well as several atmospheric parameters such as wind, relative humidity, temperature and turbulence characteristics. Using numerical computation, we examine the effect of each physical parameter on the correlations in the time series of a given experiment. We then use a parametric-likelihood approach to validate the modeling and estimate atmosphere parameters from the POLARBEAR-I project first season data set. We compare our results to previous st...

  7. Future CMB cosmological constraints in a dark coupled universe

    E-Print Network [OSTI]

    Matteo Martinelli; Laura Lopez Honorez; Alessandro Melchiorri; Olga Mena

    2010-04-14

    Cosmic Microwave Background satellite missions as the on-going Planck experiment are expected to provide the strongest constraints on a wide set of cosmological parameters. Those constraints, however, could be weakened when the assumption of a cosmological constant as the dark energy component is removed. Here we show that it will indeed be the case when there exists a coupling among the dark energy and the dark matter fluids. In particular, the expected errors on key parameters as the cold dark matter density and the angular diameter distance at decoupling are significantly larger when a dark coupling is introduced. We show that it will be the case also for future satellite missions as EPIC, unless CMB lensing extraction is performed.

  8. CMB Anomalies after Planck

    E-Print Network [OSTI]

    Schwarz, Dominik J; Huterer, Dragan; Starkman, Glenn D

    2015-01-01

    Several unexpected features have been observed in the microwave sky at large angular scales, both by WMAP an by Planck. Among those features is a lack of both variance and correlation on the largest angular scales, alignment of the lowest multipole moments with one another and with the motion and geometry of the Solar System, a hemispherical power asymmetry or dipolar power modulation, a preference for odd parity modes and an unexpectedly large cold spot in the Southern hemisphere. The individual p-values of the significance of these features are in the per mille to per cent level, when compared to the expectations of the best-fit inflationary $\\Lambda$CDM model. Some pairs of those features are demonstrably uncorrelated, increasing their combined statistical significance and indicating a significant detection of CMB features at angular scales larger than a few degrees on top of the standard model. Despite numerous detailed investigations, we still lack a clear understanding of these large-scale features, whi...

  9. Cosmological implications of the CMB large-scale structure

    SciTech Connect (OSTI)

    Melia, Fulvio

    2015-01-01

    The Wilkinson Microwave Anisotropy Probe (WMAP) and Planck may have uncovered several anomalies in the full cosmic microwave background (CMB) sky that could indicate possible new physics driving the growth of density fluctuations in the early universe. These include an unusually low power at the largest scales and an apparent alignment of the quadrupole and octopole moments. In a ?CDM model where the CMB is described by a Gaussian Random Field, the quadrupole and octopole moments should be statistically independent. The emergence of these low probability features may simply be due to posterior selections from many such possible effects, whose occurrence would therefore not be as unlikely as one might naively infer. If this is not the case, however, and if these features are not due to effects such as foreground contamination, their combined statistical significance would be equal to the product of their individual significances. In the absence of such extraneous factors, and ignoring the biasing due to posterior selection, the missing large-angle correlations would have a probability as low as ?0.1% and the low-l multipole alignment would be unlikely at the ?4.9% level; under the least favorable conditions, their simultaneous observation in the context of the standard model could then be likely at only the ?0.005% level. In this paper, we explore the possibility that these features are indeed anomalous, and show that the corresponding probability of CMB multipole alignment in the R{sub h}=ct universe would then be ?7–10%, depending on the number of large-scale Sachs–Wolfe induced fluctuations. Since the low power at the largest spatial scales is reproduced in this cosmology without the need to invoke cosmic variance, the overall likelihood of observing both of these features in the CMB is ?7%, much more likely than in ?CDM, if the anomalies are real. The key physical ingredient responsible for this difference is the existence in the former of a maximum fluctuation size at the time of recombination, which is absent in the latter because of inflation.

  10. Joint Planck and WMAP Assessment of Low CMB Multipoles

    E-Print Network [OSTI]

    Iqbal, Asif; Souradeep, Tarun; Malik, Manzoor A

    2015-01-01

    The remarkable progress in cosmic microwave background (CMB) studies over past decade has led to the era of precision cosmology in striking agreement with the $\\Lambda$CDM model. However, the lack of power in the CMB temperature anisotropies at large angular scales (low-$\\ell$), as has been confirmed by the recent Planck data also (up to $\\ell=40$), is still an open problem. One can avoid to seek an explanation for this problem by attributing the lack of power to cosmic variance or can look for explanations i.e., different inflationary potentials or initial conditions for inflation to begin with, non-trivial topology, ISW effect etc. Features in the primordial power spectrum (PPS) motivated by the early universe physics has been the most common solution to address this problem. In the present work we also follow this approach and consider a set of PPS which have features and constrain the parameters of those using WMAP 9 year and Planck data employing Markov-Chain Monte Carlo (MCMC) analysis. The prominent fe...

  11. Number Count of Peaks in the CMB Map

    E-Print Network [OSTI]

    Toshifumi Futamase; Masahiro Takada

    2000-09-11

    We investigate the dependence of cosmological parameters on the number count of peaks (local maxima and minima) in the cosmic microwave background (CMB) sky. The peak statistics contains the whole information of acoustic oscillations in the angular power spectrum $C_l$ over $l$-space and thus it can place complementary constraints on the cosmological parameters to those obtained from measurements of $C_l$. Based on the instrumental specifications of Planck, we find that the number count of peaks can provide new constraints on the combination of the matter density $\\Omega_{\\rm m}$ and the Hubble parameter $h$ approximately scaled as $\\Omega_{\\rm m} h^{-4.9}$ for a flat $\\Lambda$CDM model with $\\Omega_{m}=0.3$ and $h=0.7$. Therefore, we suggest that combining it with the constraints from $C_l$ scaled as $\\Omega_{m}h^{3.8}$ (or commonly $\\Omega_{\\rm m}h^2$) can potentially determine $\\Omega_{\\rm m}$ or equivalently solve the cosmic degeneracy by the CMB data alone.

  12. Considerations in optimizing CMB polarization experiments to constrain inflationary physics

    E-Print Network [OSTI]

    Licia Verde; Hiranya Peiris; Raul Jimenez

    2006-01-27

    We quantify the limiting factors in optimizing current-technology cosmic microwave background (CMB) polarization experiments in order to learn about inflationary physics. We consider space-based, balloon-borne and ground-based experiments. We find that foreground contamination and residuals from foreground subtraction are ultimately the limiting factors in detecting a primordial gravity wave signal. For full-sky space-based experiments, these factors hinder the detection of tensor-to-scalar ratios of r 3-sigma) tensor component in a realistic CMB experiment, inflation must either involve large-field variations, \\Delta\\phi >~ 1 or multi-field/hybrid models. Hybrid models can be easily distinguished from large-field models due to their blue scalar spectral index. Therefore, an observation of a tensor/scalar ratio and n < 1 in future experiments with the characteristics considered here may be an indication that inflation is being driven by some physics in which the inflaton cannot be described as a fundamental field.

  13. A Hidden Dark Matter Sector, Dark Radiation, and the CMB

    E-Print Network [OSTI]

    Chacko, Zackaria; Hong, Sungwoo; Okui, Takemichi

    2015-01-01

    We consider theories where dark matter is composed of a thermal relic of weak scale mass, whose couplings to the Standard Model (SM) are however too small to give rise to the observed abundance. Instead, the abundance is set by annihilation to light hidden sector states that carry no charges under the SM gauge interactions. In such a scenario the constraints from direct and indirect detection, and from collider searches for dark matter, can easily be satisfied. The masses of such light hidden states can be protected by symmetry if they are Nambu-Goldstone bosons, fermions, or gauge bosons. These states can then contribute to the cosmic energy density as dark radiation, leading to observable signals in the cosmic microwave background (CMB). Furthermore, depending on whether or not the light hidden sector states self-interact, the fraction of the total energy density that free-streams is either decreased or increased, leading to characteristic effects on both the scalar and tensor components of the CMB anisotro...

  14. Large scale CMB anomalies from thawing cosmic strings

    E-Print Network [OSTI]

    Ringeval, Christophe; Yokoyama, Jun'ichi; Bouchet, Francois R

    2015-01-01

    Cosmic strings formed during inflation are expected to be either diluted over super-Hubble distances, i.e., invisible today, or to have crossed our past light cone very recently. We discuss the latter situation in which a few strings imprint their signature in the Cosmic Microwave Background (CMB) Anisotropies after recombination. Being almost frozen in the Hubble flow, these strings are quasi static and evade almost all of the previously derived constraints on their tension while being able to source large scale anisotropies in the CMB sky. Using a local variance estimator on thousand of numerically simulated Nambu-Goto all sky maps, we compute the expected signal and show that it can mimic a dipole modulation at large angular scales while being negligible at small angles. Interestingly, such a scenario generically produces one cold spot from the thawing of a cosmic string loop. Mixed with anisotropies of inflationary origin, we find that a few strings of tension GU = O(1) x 10^(-6) match the amplitude of th...

  15. Large scale CMB anomalies from thawing cosmic strings

    E-Print Network [OSTI]

    Christophe Ringeval; Daisuke Yamauchi; Jun'ichi Yokoyama; Francois R. Bouchet

    2015-10-07

    Cosmic strings formed during inflation are expected to be either diluted over super-Hubble distances, i.e., invisible today, or to have crossed our past light cone very recently. We discuss the latter situation in which a few strings imprint their signature in the Cosmic Microwave Background (CMB) Anisotropies after recombination. Being almost frozen in the Hubble flow, these strings are quasi static and evade almost all of the previously derived constraints on their tension while being able to source large scale anisotropies in the CMB sky. Using a local variance estimator on thousand of numerically simulated Nambu-Goto all sky maps, we compute the expected signal and show that it can mimic a dipole modulation at large angular scales while being negligible at small angles. Interestingly, such a scenario generically produces one cold spot from the thawing of a cosmic string loop. Mixed with anisotropies of inflationary origin, we find that a few strings of tension GU = O(1) x 10^(-6) match the amplitude of the dipole modulation reported in the Planck satellite measurements and could be at the origin of other large scale anomalies.

  16. Tomography of the Reionization Epoch with Multifrequency CMB Observations

    E-Print Network [OSTI]

    Carlos Hernandez-Monteagudo; Licia Verde; Raul Jimenez

    2006-04-14

    We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise ratio for the detection of the signal introduced in the CMB by resonant scattering off metals at the end of the Dark Ages. We take into account systematics associated to inter-channel calibration, PSF reconstruction errors and innacurate foreground removal. We develop an algorithm to optimally extract the signal generated by metals during reionisation and to remove accurately the contamination due to the thermal Sunyaev-Zel'dovich effect. Although demanding levels of foreground characterisation and control of systematics are required, they are very distinct from those encountered in HI-21cm studies and CMB polarization, and this fact encourages the study of resonant scattering off metals as an alternative way of conducting tomography of the reionisation epoch. An ACT-like experiment with optimistic assumtions on systematic effects, and looking at clean regions of the sky, can detect changes of 3%-12% (95% c.l.) of the OIII abundance (with respect its solar value) in the redshift range $z\\in$ [12,22], for reionization redshift $z_{\\rm re}>10$. However, for $z_{\\rm re} <10$, it can only set upper limits on NII abundance increments of $\\sim$ 60% its solar value in the redshift range $z\\in$ [5.5,9], (95% c.l.). These constraints assume that inter-channel calibration is accurate down to one part in $10^{4}$, which constitutes the most critical technical requirement of this method, but still achievable with current technology.

  17. A Hidden Dark Matter Sector, Dark Radiation, and the CMB

    E-Print Network [OSTI]

    Zackaria Chacko; Yanou Cui; Sungwoo Hong; Takemichi Okui

    2015-05-15

    We consider theories where dark matter is composed of a thermal relic of weak scale mass, whose couplings to the Standard Model (SM) are however too small to give rise to the observed abundance. Instead, the abundance is set by annihilation to light hidden sector states that carry no charges under the SM gauge interactions. In such a scenario the constraints from direct and indirect detection, and from collider searches for dark matter, can easily be satisfied. The masses of such light hidden states can be protected by symmetry if they are Nambu-Goldstone bosons, fermions, or gauge bosons. These states can then contribute to the cosmic energy density as dark radiation, leading to observable signals in the cosmic microwave background (CMB). Furthermore, depending on whether or not the light hidden sector states self-interact, the fraction of the total energy density that free-streams is either decreased or increased, leading to characteristic effects on both the scalar and tensor components of the CMB anisotropy that allows these two cases to be distinguished. The magnitude of these signals depends on the number of light degrees of freedom in the hidden sector, and on the temperature at which it kinetically decouples from the SM. We consider a simple model that realizes this scenario, based on a framework in which the SM and hidden sector are initially in thermal equilibrium through the Higgs portal, and show that the resulting signals are compatible with recent Planck results, while large enough to be detected in upcoming experiments such as CMBPol and CMB Stage-IV. Invisible decays of the Higgs into hidden sector states at colliders can offer a complementary probe of this model.

  18. Cosmic Microwave Background

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsClusterInformationContractCorporate Culture |Cosmic Frontier High

  19. INTRODUCING MEXICAN NEEDLETS FOR CMB ANALYSIS: ISSUES FOR PRACTICAL APPLICATIONS AND COMPARISON WITH STANDARD NEEDLETS

    SciTech Connect (OSTI)

    Scodeller, S.; Rudjord, Oe.; Hansen, F. K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway); Marinucci, D. [Dipartimento di Matematica, Universita di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, I-00133 Roma (Italy); Geller, D.; Mayeli, A., E-mail: sandro.scodeller@astro.uio.no [Department of Mathematics, Stony Brook University, Stony Brook, NY 11794-3651 (United States)

    2011-06-01

    Over the last few years, needlets have emerged as a useful tool for the analysis of cosmic microwave background (CMB) data. Our aim in this paper is first to introduce into the CMB literature a different form of needlets, known as Mexican needlets, first discussed in the mathematical literature by Geller and Mayeli. We then proceed with an extensive study of the properties of both standard and Mexican needlets; these properties depend on some parameters which can be tuned in order to optimize the performance for a given application. Our second aim in this paper is then to give practical advice on how to adjust these parameters for WMAP and Planck data in order to achieve the best properties for a given problem in CMB data analysis. In particular, we investigate localization properties in real and harmonic space and propose a recipe for quantifying the influence of galactic and point-source masks on the needlet coefficients. We also show that for certain parameter values, the Mexican needlets provide a close approximation to the Spherical Mexican Hat Wavelets (whence their name), with some advantages concerning their numerical implementation and derivation of their statistical properties.

  20. Oxygen pumping II: Probing the Inhomogeneous Metal Enrichment at the Epoch of Reionization with High Frequency CMB Observations

    E-Print Network [OSTI]

    Carlos Hernandez-Monteagudo; Zoltan Haiman; Licia Verde; Raul Jimenez

    2007-09-20

    At the epoch of reionization, when the high-redshift inter-galactic medium (IGM) is being enriched with metals, the 63.2 micron fine structure line of OI is pumped by the ~ 1300 AA soft UV background and introduces a spectral distortion in the Cosmic Microwave Background (CMB). Here we use a toy model for the spatial distribution of neutral oxygen, assuming metal bubbles surround dark matter halos, and compute the fluctuations of this distortion, and the angular power spectrum it imprints on the CMB. We discuss the dependence of the power spectrum on the velocity of the winds polluting the IGM with metals, the minimum mass of the halos producing these winds, and on the cosmic epoch when the OI pumping occurs. We find that, although the clustering signal of the CMB distortion is weak \\delta y_{rms} ~ 10^{-7} (roughly corresponding to a temperature anisotropy of few nK), it may be reachable in deep integrations with high-sensitivity infrared detectors. Even without a detection, these instruments should be able to useful constraints on the heavy element enrichment history of the IGM.

  1. What is the distance to the CMB?

    SciTech Connect (OSTI)

    Clarkson, Chris; Umeh, Obinna; Maartens, Roy; Durrer, Ruth E-mail: umeobinna@gmail.com E-mail: Ruth.Durrer@unige.ch

    2014-11-01

    The success of precision cosmology depends not only on accurate observations, but also on the theoretical model --- which must be understood to at least the same level of precision. Subtle relativistic effects can lead to biased measurements if they are neglected. One such effect gives a systematic shift in the distance-redshift relation away from its background value, due to the non-linear relativistic conservation of total photon flux. We also show directly how this shift follows from a fully relativistic analysis of the geodesic deviation equation. We derive the expectation value of the shift using second-order perturbations about a concordance background, and show that the distance to last scattering is increased by 1%. We argue that neglecting this shift could lead to a significant bias in the background cosmological parameters, because it alters the meaning of the background model. A naive adjustment of CMB parameter estimation if this shift is really a correction to the background would raise the H{sub 0} value inferred from the CMB by 5%, potentially removing the tension with local measurements of H{sub 0}. Other CMB parameters which depend on the distance would also be shifted by ? 1? when combined with local H{sub 0} data. While our estimations rely on a simplistic analysis, they nevertheless illustrate that accurately defining the background model in terms of the expectation values of observables is critical when we aim to determine the model parameters at the sub-percent level.

  2. Motion induced second order temperature and y-type anisotropies after the subtraction of linear dipole in the CMB maps

    SciTech Connect (OSTI)

    Sunyaev, Rashid A.; Khatri, Rishi, E-mail: sunyaev@mpa-garching.mpg.de, E-mail: khatri@mpa-garching.mpg.de [Max Planck Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany)

    2013-03-01

    y-type spectral distortions of the cosmic microwave background allow us to detect clusters and groups of galaxies, filaments of hot gas and the non-uniformities in the warm hot intergalactic medium. Several CMB experiments (on small areas of sky) and theoretical groups (for full sky) have recently published y-type distortion maps. We propose to search for two artificial hot spots in such y-type maps resulting from the incomplete subtraction of the effect of the motion induced dipole on the cosmic microwave background sky. This dipole introduces, at second order, additional temperature and y-distortion anisotropy on the sky of amplitude few ?K which could potentially be measured by Planck HFI and Pixie experiments and can be used as a source of cross channel calibration by CMB experiments. This y-type distortion is present in every pixel and is not the result of averaging the whole sky. This distortion, calculated exactly from the known linear dipole, can be subtracted from the final y-type maps, if desired.

  3. Estimating SI violation in CMB due to non-circular beam and complex scan in minutes

    E-Print Network [OSTI]

    Pant, Nidhi; Rotti, Aditya; Mitra, Sanjit; Souradeep, Tarun

    2015-01-01

    Mild, unavoidable deviations from circular-symmetry of instrumental beams along with scan strategy can give rise to measurable Statistical Isotropy (SI) violation in Cosmic Microwave Background (CMB) experiments. If not accounted properly, this spurious signal can complicate the extraction of other SI violation signals (if any) in the data. However, estimation of this effect through exact numerical simulation is computationally intensive and time consuming. A generalized analytical formalism not only provides a quick way of estimating this signal, but also gives a detailed understanding connecting the leading beam anisotropy components to a measurable BipoSH characterisation of SI violation. In this paper, we provide an approximate generic analytical method for estimating the SI violation generated due to a non-circular (NC) beam and arbitrary scan strategy, in terms of the Bipolar Spherical Harmonic (BipoSH) spectra. Our analytical method can predict almost all the features introduced by a NC beam in a compl...

  4. How CMB and large-scale structure constrain chameleon interacting dark energy

    E-Print Network [OSTI]

    Daniel Boriero; Subinoy Das; Yvonne Y. Y. Wong

    2015-05-12

    We explore a chameleon type of interacting dark matter-dark energy scenario in which a scalar field adiabatically traces the minimum of an effective potential sourced by the dark matter density. We discuss extensively the effect of this coupling on cosmological observables, especially the parameter degeneracies expected to arise between the model parameters and other cosmological parameters, and then test the model against observations of the cosmic microwave background (CMB) anisotropies and other cosmological probes. We find that the chameleon parameters $\\alpha$ and $\\beta$, which determine respectively the slope of the scalar field potential and the dark matter-dark energy coupling strength, can be constrained to $\\alpha radiation component, despite a passing similarity between the two scenarios in that they both delay the epoch of matter-radiation equality. Based on the derived parameter constraints, we discuss possible signatures of the model for ongoing and future large-scale structure surveys.

  5. Dark matter CMB constraints and likelihoods for poor particle physicists

    SciTech Connect (OSTI)

    Cline, James M.; Scott, Pat, E-mail: jcline@physics.mcgill.ca, E-mail: patscott@physics.mcgill.ca [Department of Physics, McGill University, 3600 rue University, Montréal, QC, H3A 2T8 (Canada)

    2013-03-01

    The cosmic microwave background provides constraints on the annihilation and decay of light dark matter at redshifts between 100 and 1000, the strength of which depends upon the fraction of energy ending up in the form of electrons and photons. The resulting constraints are usually presented for a limited selection of annihilation and decay channels. Here we provide constraints on the annihilation cross section and decay rate, at discrete values of the dark matter mass m{sub ?}, for all the annihilation and decay channels whose secondary spectra have been computed using PYTHIA in arXiv:1012.4515 (''PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection''), namely e, ?, ?, V ? e, V ? ?, V ? ?, u, d s, c, b, t, ?, g, W, Z and h. By interpolating in mass, these can be used to find the CMB constraints and likelihood functions from WMAP7 and Planck for a wide range of dark matter models, including those with annihilation or decay into a linear combination of different channels.

  6. Contamination of early-type galaxy alignments to galaxy lensing-CMB lensing cross-correlation

    E-Print Network [OSTI]

    Chisari, Nora Elisa; Miller, Lance; Allison, Rupert

    2015-01-01

    Galaxy shapes are subject to distortions due to the tidal field of the Universe. The cross-correlation of galaxy lensing with the lensing of the Cosmic Microwave Background (CMB) cannot easily be separated from the cross-correlation of galaxy intrinsic shapes with CMB lensing. Previous work suggested that the intrinsic alignment contamination can be $15\\%$ of this cross-spectrum for the CFHT Stripe 82 (CS82) and Atacama Cosmology Telescope surveys. Here we re-examine these estimates using up-to-date observational constraints of intrinsic alignments at a redshift more similar to that of CS82 galaxies. We find a $\\approx$ $10\\%$ contamination of the cross-spectrum from red galaxies, with $\\approx$ $3\\%$ uncertainty due to uncertainties in the redshift distribution of source galaxies and the modelling of the spectral energy distribution. Blue galaxies are consistent with being unaligned, but could contaminate the cross-spectrum by an additional $9.5\\%$ within current $95\\%$ confidence levels. While our fiducial ...

  7. Primordial Magnetic Field Effects on the CMB and Large-Scale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yamazaki, Dai G.; Ichiki, Kiyotomo; Kajino, Toshitaka; Mathews, Grant J.

    2010-01-01

    Magnetic fields are everywhere in nature, and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the turbulent high-temperature environment of the big bang. Such a primordial magnetic field (PMF) would be expected to manifest itself in the cosmic microwave background (CMB) temperature and polarization anisotropies, and also in the formation of large-scale structure. In this paper, we summarize the theoretical framework which we have developed to calculate the PMF power spectrum to high precision. Using this formulation, wemore »summarize calculations of the effects of a PMF which take accurate quantitative account of the time evolution of the cutoff scale. We review the constructed numerical program, which is without approximation, and an improvement over the approach used in a number of previous works for studying the effect of the PMF on the cosmological perturbations. We demonstrate how the PMF is an important cosmological physical process on small scales. We also summarize the current constraints on the PMF amplitudeB?and the power spectral indexnBwhich have been deduced from the available CMB observational data by using our computational framework.« less

  8. Can residuals of the solar system foreground explain low multipole anomalies of the CMB?

    SciTech Connect (OSTI)

    Hansen, M.; Kim, J.; Frejsel, A.M.; Ramazanov, S.; Naselsky, P.; Zhao, W. [Niels Bohr Institute and DISCOVERY Center, Blegdamsvej 17, 2100 Copenhagen, Ø (Denmark); Burigana, C., E-mail: kirstejn@nbi.dk, E-mail: jkim@nbi.dk, E-mail: annemett@nbi.dk, E-mail: sabir_ra@nbi.dk, E-mail: naselsky@nbi.dk, E-mail: wzhao7@nbi.ku.dk, E-mail: burigana@iasfbo.inaf.it [INAF/IASF, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via P. Gobetti 101, 40129, Bologna (Italy)

    2012-10-01

    The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or foregrounds. An example of a foreground, which could generate some non-Gaussian and statistically anisotropic features at low multipole range, is the very symmetric Kuiper Belt in the outer solar system. In this paper, expanding upon the methods presented in [1], we investigate the contributions from the Kuiper Belt objects (KBO) to the WMAP ILC 7 map, whereby we can minimize the contrast in power between even and odd multipoles in the CMB, discussed in [2,3]. We submit our KBO de-correlated CMB signal to several tests, to analyze its validity, and find that incorporation of the KBO emission can decrease the quadrupole-octupole alignment and parity asymmetry problems, provided that the KBO signals has a non-cosmological dipole modulation, associated with the statistical anisotropy of the ILC 7 map. Additionally, we show that the amplitude of the dipole modulation, within a 2? interval, is in agreement with the corresponding amplitudes, discussed in [4].

  9. Precision epoch of reionization studies with next-generation CMB experiments

    SciTech Connect (OSTI)

    Calabrese, Erminia; Louis, Thibaut [Sub-department of Astrophysics, University of Oxford, Keble Road, Oxford, OX1 3RH (United Kingdom); Hložek, Renée; Hil, J. Colin [Department of Astrophysical Science, Peyton Hall, 4 Ivy Lane, Princeton, NJ, 08544 (United States); Battaglia, Nick [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA, 15213 (United States); Bond, J. Richard; Hajian, Amir [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St George Street, Toronto, ON, M5S 3H8 Canada (Canada); De Bernardis, Francesco; Henderson, Shawn; Niemack, Michael D. [Department of Physics, Cornell University, 109 Clark Hall, Ithaca, NY, 14853 (United States); Devlin, Mark J. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, 19104 (United States); Kosowsky, Arthur [Department of Physics and Astronomy, University of Pittsburgh, 315 Allen Hall, Pittsburgh, PA, 15260 (United States); McMahon, Jeff [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI, 48109 (United States); Moodley, Kavilan [Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4041 South Africa (South Africa); Newburgh, Laura [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George St., Toronto, ON, M5S 3H4 Canada (Canada); Page, Lyman A. [Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Washington Road, Princeton, NJ, 08544 (United States); Partridge, Bruce [Department of Physics and Astronomy, Haverford College, 370 Lancaster Avenue, Haverford, PA, 19041 (United States); Sehgal, Neelima, E-mail: erminia.calabrese@astro.ox.ac.uk, E-mail: rhlozek@astro.princeton.edu [Physics and Astronomy Department, Stony Brook University, Stony Brook, NY, 11794 (United States); and others

    2014-08-01

    Future arcminute resolution polarization data from ground-based Cosmic Microwave Background (CMB) observations can be used to estimate the contribution to the temperature power spectrum from the primary anisotropies and to uncover the signature of reionization near ?=1500 in the small angular-scale temperature measurements. Our projections are based on combining expected small-scale E-mode polarization measurements from Advanced ACTPol in the range 300CMB polarization is used to break degeneracies between primordial and secondary terms present in temperature and, in effect, to remove from the temperature data all but the residual kSZ term. We estimate a 15? detection of the diffuse homogeneous kSZ signal from expected AdvACT temperature data at ?>1500, leading to a measurement of the amplitude of matter density fluctuations, ?{sub 8}, at 1% precision. Alternatively, by exploring the reionization signal encoded in the patchy kSZ measurements, we bound the time and duration of the reionization with ?(z{sub re})=1.1 and ?(?z{sub re})=0.2. We find that these constraints degrade rapidly with large beam sizes, which highlights the importance of arcminute-scale resolution for future CMB surveys.

  10. CMB @ 50 & NERSC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L OBransenBusinessInitialRadiological Surveys Core Status:CMB @

  11. Comptonization of cosmic microwave background by cold ultra-relativistic electron-positron pulsar wind and origin of ~100 GeV lines

    E-Print Network [OSTI]

    Iakubovskyi, Dmytro

    2015-01-01

    Previously, [1207.0458] proposed an astrophysical explanation of narrow gamma-ray line-like feature(s) at ~100 GeV from Galactic Center region observed by Fermi/LAT [1205.4700]. The model of [1207.0458] is based on the inverse Compton scattering of external ultra-violet/X-ray radiation by a cold ultra-relativistic electron-positron pulsar wind. We show that the extra broad ~30 MeV component should arise from Comptonization of cosmic microwave background radiation. We estimate the main parameters of this component and show that it can be detectable with MeV telescopes such as CGRO/COMPTEL. The location of CGRO/COMPTEL unidentified source GRO J1823-12 close to excess of 105-120 GeV emission (Reg.1 of [1205.4700]) can be interpreted as an argument in favour of astrophysical model of the narrow feature(s) at ~100 GeV.

  12. MICROWAVE EMISSION FROM THE EDGEWORTH-KUIPER BELT AND THE ASTEROID BELT CONSTRAINED FROM THE WILKINSON MICROWAVE ANISOTROPY PROBE

    SciTech Connect (OSTI)

    Ichikawa, Kazuhide; Fukugita, Masataka [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan)

    2011-08-01

    Objects in the Edgeworth-Kuiper Belt and the main asteroid belt should emit microwaves that may give rise to extra anisotropy signals in the multipole of the cosmic microwave background (CMB) experiment. Constraints are derived from the absence of positive detection of such anisotropies for l {approx}< 50, meaning the total mass of Edgeworth-Kuiper Belt objects is smaller than 0.2 M{sub +}. This limit is consistent with the mass extrapolated from the observable population with the size of a {approx}> 15 km, assuming that the small-object population follows the power law in size dN/da {approx} a{sup -q} with the canonical index expected for collisional equilibrium, q {approx_equal} 3.5, with which 23% of the mass is ascribed to objects smaller than are observationally accessible down to grains. A similar argument applied to the main asteroid belt indicates that the grain population should not increase more quickly than q {approx_equal} 3.6 toward smaller radii, if the grain population follows the power law that continues to observed asteroids with larger radii. Both cases are at or only slightly above the limit that can be physically significant, implying the importance of further tightening the CMB anisotropy limit, which may be attained with observation at higher radio frequencies.

  13. Correlating anomalies of the microwave sky: The Good, the Evil and the Axis

    E-Print Network [OSTI]

    Aleksandar Rakic; Dominik J. Schwarz

    2007-05-11

    At the largest angular scales the presence of a number of unexpected features has been confirmed by the latest measurements of the cosmic microwave background (CMB). Among them are the anomalous alignment of the quadrupole and octopole with each other as well as the stubborn lack of angular correlation on scales >60deg. We search for correlations between these two phenomena and demonstrate their absence. A Monte Carlo likelihood analysis confirms previous studies and shows that the joint likelihood of both anomalies is incompatible with the best-fit Lambda Cold Dark Matter model at >99.95% C.L. At the same time, a presumed special axis (the `Axis of Evil') identified on the microwave sky demands additional contributions to multipole power on top of the primordial standard inflationary ones. We find that the notion of a preferred axis in the CMB is misleading and inconsistent with three-year data from the Wilkinson Microwave Anisotropy Probe (WMAP). Rather the data require a preferred plane, whereupon the axis is just the normal direction to that plane. Rotational symmetry within that plane is inconsistent with the observations and is ruled out at high confidence.

  14. Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps

    E-Print Network [OSTI]

    Masahiro Takada; Toshifumi Futamase

    2000-08-24

    We present quantitative investigations of the weak lensing effect on the two-point correlation functions of local maxima (hotspots), $\\xipk(\\theta)$, in the cosmic microwave background (CMB) maps. The lensing effect depends on the projected mass fluctuations between today and the redshift $z_{\\rm rec}\\approx1100$. If adopting the Gaussian assumption for the primordial temperature fluctuations field, the peak statistics can provide an additional information about the intrinsic distribution of hotspots that those pairs have some characteristic separation angles. The weak lensing then redistributes hotspots in the observed CMB maps from the intrinsic distribution and consequently imprints non-Gaussian signatures onto $\\xipk(\\theta)$. Especially, since the intrinsic $\\xipk(\\theta)$ has a pronounced depression feature around the angular scale of $\\theta\\approx 70'$ for a flat universe, the weak lensing induces a large smoothing at the scale. We show that the lensing signature therefore has an advantage to effectively probe mass fluctuations with large wavelength modes around $\\lambda\\approx 50 h^{-1}{\\rm Mpc}$. To reveal the detectability, we performed numerical experiments with specifications of {\\em MAP} and {\\em Planck Surveyor} including the instrumental effects of beam smoothing and detector noise. It is then found that our method can successfully provide constraints on amplitude of the mass fluctuations and cosmological parameters in a flat universe with and without cosmological constant, provided that we use maps with 65% sky coverage expected from Planck.

  15. Toward a tomographic analysis of the cross-correlation between Planck CMB lensing and H-ATLAS galaxies

    E-Print Network [OSTI]

    Bianchini, Federico; Calabrese, Matteo; Bielewicz, Pawel; Gonzalez-Nuevo, Joaquin; Baccigalupi, Carlo; Danese, Luigi; de Zotti, Gianfranco; Bourne, Nathan; Cooray, Asantha; Dunne, Loretta; Eales, Stephen

    2015-01-01

    We present an improved and extended analysis of the cross-correlation between the map of the Cosmic Microwave Background (CMB) lensing potential derived from the Planck mission data and the high-redshift galaxies detected by the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) in the photometric redshift range $z_{\\rm ph} \\ge 1.5$. We compare the results based on the 2013 and 2015 Planck datasets, and investigate the impact of different selections of the H-ATLAS galaxy samples. Significant improvements over our previous analysis have been achieved thanks to the higher signal-to-noise ratio of the new CMB lensing map recently released by the Planck collaboration. The effective galaxy bias parameter, $b$, for the full galaxy sample, derived from a joint analysis of the cross-power spectrum and of the galaxy auto-power spectrum is found to be $b = 3.54^{+0.15}_{-0.14}$. Furthermore, a first tomographic analysis of the cross-correlation signal is implemented, by splitting the galaxy sample into two re...

  16. Constraining primordial magnetic fields with distortions of the black-body spectrum of the cosmic microwave background: pre- and post-decoupling contributions

    SciTech Connect (OSTI)

    Kunze, Kerstin E. [Departamento de Física Fundamental and IUFFyM, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain); Komatsu, Eiichiro, E-mail: kkunze@usal.es, E-mail: komatsu@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild Str. 1, 85741 Garching (Germany)

    2014-01-01

    Primordial magnetic fields that exist before the photon-baryon decoupling epoch are damped on length scales below the photon diffusion and free-streaming scales. The energy injected into the plasma by dissipation of magnetosonic and Alfv and apos;en waves heats photons, creating a y-type distortion of the black-body spectrum of the cosmic microwave background. This y-type distortion is converted into a ?-type distortion when elastic Compton scattering is efficient. Therefore, we can use observational limits on y- and ?-type distortions to constrain properties of magnetic fields in the early universe. Assuming a Gaussian, random, and non-helical field, we calculate ? and y as a function of the present-day strength of the field, B{sub 0}, smoothed over a certain Gaussian width, k{sub c}{sup ?1}, as well as of the spectral index of the power spectrum of fields, n{sub B}, defined by P{sub B}(k)?k{sup n{sub B}}. For a nearly scale-invariant spectrum with n{sub B} = ?2.9 and a Gaussian smoothing width of k{sub c}{sup ?1} = 1Mpc, the existing COBE/FIRAS limit on ? yields B{sub 0} < 40 nG, whereas the projected PIXIE limit on ? would yield B{sub 0} < 0.8 nG. For non-scale-invariant spectra, constraints can be stronger. For example, for B{sub 0} = 1 nG with k{sub c}{sup ?1} = 1Mpc, the COBE/FIRAS limit on ? excludes a wide range of spectral indices given by n{sub B} > ?2.6. After decoupling, energy dissipation is due to ambipolar diffusion and decaying MHD turbulence, creating a y-type distortion. The distortion is completely dominated by decaying MHD turbulence, and is of order y ? 10{sup ?7} for a few nG field smoothed over the damping scale at the decoupling epoch, k{sub d,} {sub dec} ? 290(B{sub 0}/1nG){sup ?1}Mpc{sup ?1}. The projected PIXIE limit on y would exclude B{sub 0} > 1.0 and 0.6 nG for n{sub B} = ?2.9 and -2.3, respectively, and B{sub 0} > 0.6 nG for n{sub B} ? 2. Finally, we find that the current limits on the optical depth to Thomson scattering restrict the predicted y-type distortion to be y?<10{sup ?8}.

  17. The Cosmic Background Radiation

    E-Print Network [OSTI]

    George Smoot; Douglas Scott

    1997-11-08

    We summarise the current status of cosmic microwave background spectrum and anisotropy measurements, and their theoretical interpretation. This is the update of the mini-review for the 1997 web-version of the Review of Particle Properties.

  18. Correlated mixture between adiabatic and isocurvature fluctuations and recent CMB observations

    SciTech Connect (OSTI)

    Andrade, Ana Paula A.; Wuensche, Carlos Alexandre; Ribeiro, Andre Luis Batista [Divisao de Astrofisica, Instituto Nacional de Pesquisas Espaciais/MCT, Sao Jose dos Campos, Sao Paulo (Brazil) and Laboratorio de Astrofisica Teorica e Observacional DCET/UESC, Ilheus, Bahia (Brazil); Divisao de Astrofisica, Instituto Nacional de Pesquisas Espaciais/MCT, Sao Jose dos Campos, Sao Paulo (Brazil); Laboratorio de Astrofisica Teorica e Observacional, DCET/UESC, Ilheus, Bahia (Brazil)

    2005-02-15

    This work presents a reduced {chi}{sub {nu}}{sup 2} test to search for non-Gaussian signals in the cosmic microwave background radiation (CMBR) TT power spectrum of recent CMBR data, Wilkinson Anisotropy Microwave Probe, Arcminute Cosmology Bolometer Array Receiver, and Cosmic Background Imager data sets, assuming a mixed density field including adiabatic and isocurvature fluctuations. We assume a skew positive mixed model with adiabatic inflation perturbations plus additional isocurvature perturbations possibly produced by topological defects. The joint probability distribution used in this context is a weighted combination of Gaussian and non-Gaussian random fields. Results from simulations of CMBR temperature for the mixed field show a distinct signature in CMB power spectrum for very small deviations ({approx}0.1%) from a pure Gaussian field, and can be used as a direct test for the nature of primordial fluctuations. A reduced {chi}{sub {nu}}{sup 2} test applied on the most recent CMBR observations reveals that an isocurvature fluctuations field is not ruled out and indeed permits a very good description for a flat geometry {lambda}-CDM Universe, {chi}{sub 930}{sup 2}{approx}1.5, rather than the simple inflationary standard model with {chi}{sub 930}{sup 2}{approx}2.3. This result may looks is particular discrepant with the reduced {chi}{sup 2} of 1.07 obtained with the same model in Spergel et al. [Astrophys. J. 148, 175 (2003)] for temperature only, however, our work is restricted to a region of the parameter space that does not include the best fit model for TT only of Spergel et al.

  19. Two Phase Dynamics as the Origin to: 0.25 keV and 0.1 keV X-ray Diffuse Backgrounds, CMB, Global Quantized Redshift, 10 Mpc Space distributions and 30 Myr Cycles at Earth Phenomena

    E-Print Network [OSTI]

    Eduardo del Pozo Garcia

    2015-02-25

    An Alternative to explain the origin of matter-background connections from the paper "Do Cosmic Backgrounds Cyclical Renew by Matter and Quanta Emissions?..." proposed: A sequence of discontinuous small changes of light speed in time as the cause, which provoke that criticality processes take place every 26-30 million years. Then, matter particles and quanta reach at one threshold value, and are compelled to reorganize their internal energy and make emissions that later becomes in current cosmic backgrounds. The small discontinues relative decreasing of c of about 10 -5) should do some small effects on planet and living bodies. Cyclic small reorganization of matter particles is consider as the astrophysical origin of Earth cyclic catastrophes. And at space global distribution: quantized redshift, change of galaxy fractal distribution at 10 Mpc scale, galaxy average luminosity and the luminosity fluctuation of galaxy pairs are enhanced out to separations near 10 Mpc. Also proposed: Like the Universe is observed flat in distance and time, the gravitational constant G might decrease with time, which may originate the Earth orbit eccentricity cycle of 100000 yr and, provoke the former mentioned sequence of c decrease in time. And, every 6 million years, the accumulation of G relative decrease of about 10-5 in G compelled space-time to reach at one threshold value that, trigger small relative decrease of light speed c of about 10-5 cyclically. This is interpreted as the Universe has two dynamical phases following one each other cyclically with intervals of 26-30 million years respectively: One of about 0.1 million years, called "activation phase", at which the critical processes take place, follows by longer "inhibition phase". The present approach indicates the existence of a subtle non linear dynamics, which could also contribute to the origin of galaxy fractal distribution.

  20. Clusters of galaxies in the microwave band: influence of the motion of the Solar System

    E-Print Network [OSTI]

    J. Chluba; G. Huetsi; R. A. Sunyaev

    2005-08-09

    In this work we consider the changes of the SZ cluster brightness, flux and number counts induced by the motion of the Solar System with respect to the frame defined by the cosmic microwave background (CMB). These changes are connected with the Doppler effect and aberration and exhibit a strong spectral and spatial dependence. The correction to the SZ cluster brightness and flux has an amplitude and spectral dependence, which is similar to the first order cluster peculiar velocity correction to the thermal SZ effect. Due to the change in the received cluster CMB flux the motion of the Solar System induces a dipolar asymmetry in the observed number of clusters above a given flux level. Similar effects were discussed for $\\gamma$-ray bursts and radio galaxies, but here, due to the very peculiar frequency-dependence of the thermal SZ effect, the number of observed clusters in one direction of the sky can be both, decreased or increased depending on the frequency band. A detection of this asymmetry should be possible using future full sky CMB experiments with mJy sensitivities.

  1. The impact of dipole straylight contamination on the alignment of low multipoles of CMB anisotropies

    E-Print Network [OSTI]

    A. Gruppuso; C. Burigana; F. Finelli

    2007-01-10

    We estimate the impact of the Dipole Straylight Contamination (DSC) for the {\\it Planck} satellite on the alignments of vectors associated to the low multipoles of the pattern of the cosmic microwave background (CMB) anisotropies. In particular we study how the probability distributions of eighteen estimators for the alignments change when DSC is taken into account. We find that possible residual DSC should leave a non-negligible impact on low multipole alignments for effective values of the fractional far sidelobe integrated response, $p$, larger than $\\sim {\\rm few} \\times 10^{-3}$. The effect is strongly dependent on the intrinsic sky amplitude and weakly dependent on the considered scanning strategy. We find a decrease of the alignment probability between the quadrupole and the dipole and an increase of the alignment probability between the hexadecapole and the dipole (larger is the intrinsic sky amplitude and lower is the contamination). The remaining estimators do not exhibit clear signatures, except, in some cases, considering the largest values of $p$ and the lowest sky amplitudes. Provided that the real sidelobes of the {\\it Planck} receivers in flight conditions will correspond to $p \\lsim {\\rm few} \\times 10^{-3}$, as realistically expected at least in the cosmological frequency channels, and will be known with accuracies better than $\\sim {\\rm few} \\times 10$% allowing for a suitable cleaning during data reduction, {\\it Planck} will be very weakly affected from DSC on the alignments of low multipoles.

  2. EHS-Net Microwave Study EHS-Net Microwave Study Protocol

    E-Print Network [OSTI]

    EHS-Net Microwave Study 1 EHS-Net Microwave Study Protocol Research question Is there any justification for conducting an in-depth study on potential associations between microwave oven usage in food preparation establishments and foodborne illness? Background The use of microwave ovens inherently leads

  3. CMB: The ultimate test for theoretical models aiming at describing the very early universe

    E-Print Network [OSTI]

    Mairi Sakellariadou

    2001-11-27

    In this talk, I will illustrate how one can use the cosmic microwave background anisotropy measurements, in order to test theoretical models aiming at describing the early universe.

  4. FERMI RULES OUT THE INVERSE COMPTON/CMB MODEL FOR THE LARGE-SCALE JET X-RAY EMISSION OF 3C 273

    SciTech Connect (OSTI)

    Meyer, Eileen T.; Georganopoulos, Markos

    2014-01-10

    The X-ray emission mechanism in large-scale jets of powerful radio quasars has been a source of debate in recent years, with two competing interpretations: either the X-rays are of synchrotron origin, arising from a different electron energy distribution than that producing the radio to optical synchrotron component, or they are due to inverse Compton scattering of cosmic microwave background photons (IC/CMB) by relativistic electrons in a powerful relativistic jet with bulk Lorentz factor ? ? 10-20. These two models imply radically different conditions in the large-scale jet in terms of jet speed, kinetic power, and maximum energy of the particle acceleration mechanism, with important implications for the impact of the jet on the large-scale environment. A large part of the X-ray origin debate has centered on the well-studied source 3C 273. Here we present new observations from Fermi which put an upper limit on the gamma-ray flux from the large-scale jet of 3C 273 that violates at a confidence greater that 99.9% the flux expected from the IC/CMB X-ray model found by extrapolation of the UV to X-ray spectrum of knot A, thus ruling out the IC/CMB interpretation entirely for this source when combined with previous work. Further, this upper limit from Fermi puts a limit on the Doppler beaming factor of at least ? < 9, assuming equipartition fields, and possibly as low as ? < 5, assuming no major deceleration of the jet from knots A through D1.

  5. Lensed CMB simulation and parameter estimation

    E-Print Network [OSTI]

    Antony Lewis

    2010-11-16

    Modelling of the weak lensing of the CMB will be crucial to obtain correct cosmological parameter constraints from forthcoming precision CMB anisotropy observations. The lensing affects the power spectrum as well as inducing non-Gaussianities. We discuss the simulation of full sky CMB maps in the weak lensing approximation and describe a fast numerical code. The series expansion in the deflection angle cannot be used to simulate accurate CMB maps, so a pixel remapping must be used. For parameter estimation accounting for the change in the power spectrum but assuming Gaussianity is sufficient to obtain accurate results up to Planck sensitivity using current tools. A fuller analysis may be required to obtain accurate error estimates and for more sensitive observations. We demonstrate a simple full sky simulation and subsequent parameter estimation at Planck-like sensitivity. The lensed CMB simulation and parameter estimation codes are publicly available.

  6. Second Season QUIET Observations: Measurements of the CMB Polarization Power Spectrum at 95 GHz

    SciTech Connect (OSTI)

    Araujo, D.; Bischoff, C.; Brizius, A.; Buder, I.; Chinone, Y.; Cleary, K.; Dumoulin, R.N.; Kusaka, A.; Monsalve, R.; ss, S.K.N\\ae; Newburgh, L.B.; /Columbia U., CBA /Princeton U. /Caltech

    2012-07-01

    The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95GHz. The 43-GHz results have been published in QUIET Collaboration et al. (2011), and here we report the measurement of CMB polarization power spectra using the 95-GHz data. This data set comprises 5337 hours of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 {mu}K{radical}s. Four low-foreground fields were observed, covering a total of {approx} 1000 square degrees with an effective angular resolution of 12'.8, allowing for constraints on primordial gravitational waves and high-signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C{ell} (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB and BB power spectra between {ell} = 25 and 975 and find that the EE spectrum is consistent with {Lambda}CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1{sup +0.9}{sub -0.8} (r < 2.8 at 95% C.L.) as derived by the ML pipeline, and r = {sup +0.9}{sub -0.8} (r < 2.7 at 95% C.L.) as derived by the PCL pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.

  7. Microwave detector

    DOE Patents [OSTI]

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1985-02-08

    A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  8. Illuminating the background : topics in cosmic microwave background polarization research

    E-Print Network [OSTI]

    Miller, Nathan James

    2012-01-01

    E.M. , Matsumura, T. , Dowell, C.D. , Keating, B.G. , Ade,Bierman, J. J. Bock, C. D. Dowell, L. Duband, E. F. Hivon,P. Day, C. Dickinson, D. Dowell, M. Dragovan, S. Golwala, K.

  9. Illuminating the background : topics in cosmic microwave background polarization research

    E-Print Network [OSTI]

    Miller, Nathan James

    2012-01-01

    red), QUaD (green), and BICEP (blue). The power spectrum ispower spectrum along with measurements from WMAP (red), SPT (green), andred), QUaD (green), and BICEP (blue). The power spectrum is

  10. The Cosmic Background Imager

    E-Print Network [OSTI]

    S. Padin; M. C. Shepherd; J. K. Cartwright; R. G. Keeney; B. S. Mason; T. J. Pearson; A. C. S. Readhead; W. L. Schaal; J. Sievers; P. S. Udomprasert; J. K. Yamasaki; W. L. Holzapfel; J. E. Carlstrom; M. Joy; S. T. Myers; A. Otarola

    2001-10-05

    Design and performance details are given for the Cosmic Background Imager (CBI), an interferometer array that is measuring the power spectrum of fluctuations in the cosmic microwave background radiation (CMBR) for multipoles in the range 400 switching scheme is used to reject cross-talk and low-frequency pick-up in the signal processing system. The CBI has a 3-axis mount which allows the tracking platform to be rotated about the optical axis, providing improved (u,v) coverage and a powerful discriminant against false signals generated in the receiving electronics. Rotating the tracking platform also permits polarization measurements when some of the antennas are configured for the orthogonal polarization.

  11. Lecture Notes on CMB Theory: From Nucleosynthesis to Recombination

    E-Print Network [OSTI]

    Hu, Wayne

    Lecture Notes on CMB Theory: From Nucleosynthesis to Recombination by Wayne Hu arXiv:0802.3688v1[astro-ph]25Feb2008 #12;Contents CMB Theory from Nucleosynthesis to Recombination page 1 1 Introduction 1 2 Brief Thermal History 1 2.1 Nucleosynthesis and Prediction of the CMB 1 2.2 Thermalization

  12. Vibration Background

    E-Print Network [OSTI]

    Dickinson, Kristin

    2012-01-01

    Vibration Background By Selim Özdo?an Translated by Kristinteacher says we have a vibration background, what is that? Igave some thought to our vibration background. It’s a good

  13. Computing Non- Gaussian Maps of the CMB

    E-Print Network [OSTI]

    Martin Landriau; Paul Shellard

    2003-10-10

    We discuss methods to compute maps of the CMB in models featuring active causal sources and in non-Gaussian models ofinflation. We show our large angle results as well as some preliminary results on small angles. We conclude by discussing on-going work.

  14. Relating gravitational wave constraints from primordial nucleosynthesis, pulsar timing, laser interferometers, and the CMB: implications for the early universe

    E-Print Network [OSTI]

    Latham A. Boyle; Alessandra Buonanno

    2007-08-18

    We derive a general master equation relating the gravitational-wave observables r and Omega_gw(f). Here r is the tensor-to-scalar ratio, constrained by cosmic-microwave-background (CMB) experiments; and Omega_gw(f) is the energy spectrum of primordial gravitational-waves, constrained e.g. by pulsar-timing measurements, laser-interferometer experiments, and Big Bang Nucleosynthesis (BBN). Differentiating the master equation yields a new expression for the tilt d(ln Omega_gw(f))/d(ln f). The relationship between r and Omega_gw(f) depends sensitively on the uncertain physics of the early universe, and we show that this uncertainty may be encapsulated (in a model-independent way) by two quantities: w_hat(f) and nt_hat(f), where nt_hat(f) is a certain logarithmic average over nt(k) (the primordial tensor spectral index); and w_hat(f) is a certain logarithmic average over w_tilde(a) (the effective equation-of-state in the early universe, after horizon re-entry). Here the effective equation-of-state parameter w_tilde(a) is a combination of the ordinary equation-of-state parameter w(a) and the bulk viscosity zeta(a). Thus, by comparing constraints on r and Omega_gw(f), one can obtain (remarkably tight) constraints in the [w_hat(f), nt_hat(f)] plane. In particular, this is the best way to constrain (or detect) the presence of a ``stiff'' energy component (with w > 1/3) in the early universe, prior to BBN. Finally, although most of our analysis does not assume inflation, we point out that if CMB experiments detect a non-zero value for r, then we will immediately obtain (as a free by-product) a new upper bound w_hat < 0.55 on the logarithmically averaged effective equation-of-state parameter during the ``primordial dark age'' between the end of inflation and the start of BBN.

  15. Finite Cosmology and a CMB Cold Spot

    SciTech Connect (OSTI)

    Adler, R.J.; Bjorken, J.D.; Overduin, J.M.; /Stanford U., HEPL

    2006-03-20

    The standard cosmological model posits a spatially flat universe of infinite extent. However, no observation, even in principle, could verify that the matter extends to infinity. In this work we model the universe as a finite spherical ball of dust and dark energy, and obtain a lower limit estimate of its mass and present size: the mass is at least 5 x 10{sup 23}M{sub {circle_dot}} and the present radius is at least 50 Gly. If we are not too far from the dust-ball edge we might expect to see a cold spot in the cosmic microwave background, and there might be suppression of the low multipoles in the angular power spectrum. Thus the model may be testable, at least in principle. We also obtain and discuss the geometry exterior to the dust ball; it is Schwarzschild-de Sitter with a naked singularity, and provides an interesting picture of cosmogenesis. Finally we briefly sketch how radiation and inflation eras may be incorporated into the model.

  16. Hybrid Estimation of CMB Polarization Power Spectra

    E-Print Network [OSTI]

    G. Efstathiou

    2006-01-05

    This paper generalises the hybrid power spectrum estimator developed in Efstathiou (2004a) to the estimation of polarization power spectra of the cosmic microwave background radiation. The hybrid power spectrum estimator is unbiased and we show that it is close to optimal at all multipoles, provided the pixel noise satisfies certain reasonable constraints. Furthermore, the hybrid estimator is computationally fast and can easily be incorporated in a Monte-Carlo chain for Planck-sized data sets. Simple formulae are given for the covariance matrices, including instrumental noise, and these are tested extensively against numerical simulations. We compare the behaviour of simple pseudo-Cell estimates with maximum likelihood estimates at low multipoles. For realistic sky cuts, maximum likelihood estimates reduce very significantly the mixing of E and B modes. To achieve limits on the scalar-tensor ratio of r<<0.1 from sky maps with realistic sky cuts, maximum likelihood methods, or pseudo-Cell estimators based on unambiguous E and B modes, will be essential.

  17. Microwave furnace having microwave compatible dilatometer

    DOE Patents [OSTI]

    Kimrey, H.D. Jr.; Janney, M.A.; Ferber, M.K.

    1992-03-24

    An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy. 2 figs.

  18. Microwave furnace having microwave compatible dilatometer

    DOE Patents [OSTI]

    Kimrey, Jr., Harold D. (Knoxville, TN); Janney, Mark A. (Knoxville, TN); Ferber, Mattison K. (Oak Ridge, TN)

    1992-01-01

    An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy.

  19. Suppressing CMB low multipoles with ISW effect

    SciTech Connect (OSTI)

    Das, Santanu; Souradeep, Tarun E-mail: tarun@iucaa.ernet.in

    2014-02-01

    Recent results of Planck data reveal that the power [1,2] in the low multipoles of the CMB angular power spectrum, approximately up to l = 30, is significantly lower than the theoretically predicted in the best fit ?CDM model. There are different known physical effects that can affect the power at low multipoles, such as features in the primordial power spectrum (PPS) in some models of inflation and ISW effect. In this paper we investigate the possibility of invoking the Integrated Sachs-Wolfe (ISW) effect to explain the power deficit at low multipoles. The ISW effect that originates from the late time expansion history of the universe is rich in possibilities given the limited understanding of the origin of dark energy (DE). It is a common understanding that the ISW effect adds to the power at the low multipoles of the CMB angular power spectrum. In this paper we carry out an analytic study to show that there are some expansion histories in which the ISW effect, instead of adding power, provides negative contribution to the power at low multipoles. Guided by the analytic study, we present examples of the features required in the late time expansion history of the universe that could explain the power deficiency through the ISW effect. We also show that an ISW origin of power deficiency is consistent, at present, with other cosmological observations that probe the expansion history such as distance modulus, matter power spectrum and the evolution of cluster number count. We also show that the ISW effect may be distinguished from power deficit originating from features in the PPS using the measurements of the CMB polarization spectrum at low multipoles expected from Planck. We conclude that the power at low multipoles of the CMB anisotropy could well be closely linked to Dark Energy puzzle in cosmology and this observation could be actually pointing to richer phenomenology of DE beyond the cosmological constant ?.

  20. CMB anisotropies from primordial inhomogeneous magnetic fields

    E-Print Network [OSTI]

    Antony Lewis

    2004-08-19

    Primordial inhomogeneous magnetic fields of the right strength can leave a signature on the CMB temperature anisotropy and polarization. Potentially observable contributions to polarization B-modes are generated by vorticity and gravitational waves sourced by the magnetic anisotropic stress. We compute the corresponding CMB transfer functions in detail including the effect of neutrinos. The shear rapidly causes the neutrino anisotropic stress to cancel the stress from the magnetic field, suppressing the production of gravitational waves and vorticity on super-horizon scales after neutrino decoupling. A significant large scale signal from tensor modes can only be produced before neutrino decoupling, and the actual amplitude is somewhat uncertain. Plausible values suggest primordial nearly scale invariant fields of ~ 10^(-10)G today may be observable from their large scale tensor anisotropy. They can be distinguished from primordial gravitational waves by their non-Gaussianity. Vector mode vorticity sources B-mode power on much smaller scales with a power spectrum somewhat similar to that expected from weak lensing, suggesting amplitudes ~ 10^(-9)G may be observable on small scales for a spectral index of n ~ -2.9. In the appendix we review the covariant equations for computing the vector and tensor CMB power spectra that we implement numerically.

  1. Low-frequency line temperatures of the CMB

    E-Print Network [OSTI]

    Ralf Hofmann

    2009-07-11

    Based on SU(2) Yang-Mills thermodynamics we interprete Aracde2's and the results of earlier radio-surveys on low-frequency CMB line temperatures as a phase-boundary effect. We explain the excess at low frequencies by evanescent, nonthermal photon fields of the CMB whose intensity is nulled by that of Planck distributed calibrator photons. The CMB baseline temperature thus is identified with the critical temperature of the deconfining-preconfining transition.

  2. An "Ultrasonic Image" of the Embryonic Universe: CMB Polarization Tests of the Inflationary Paradigm

    E-Print Network [OSTI]

    Brian G. Keating

    2008-06-11

    This chapter describes how the Cosmic Gravitational Wave Background induces a specific type of CMB polarization and describes the first experiment dedicated to testing this most-promising signature of inflation. This experiment, the Background Imaging of Cosmic Extragalactic Polarization (BICEP) project, has recently embarked on its third observing season. We show preliminary data from the BICEP's first season obtained with a novel polarization modulation mechanism called the "Faraday Rotation Modulator". Our discussion ends with a description of exciting new technology with the potential to probe inflation down to the GUT-scale.

  3. Non-Gaussian extrema counts for CMB maps

    SciTech Connect (OSTI)

    Pogosyan, Dmitri [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta, T6G 2G7 (Canada); Pichon, Christophe; Gay, Christophe [Institut d'astrophysique de Paris, 98, bis Boulevard Arago, 75 014, Paris (France)

    2011-10-15

    In the context of the geometrical analysis of weakly non-Gaussian cosmic microwave background maps, the 2D differential extrema counts as functions of the excursion set threshold is derived from the full moments expansion of the joint probability distribution of an isotropic random field, its gradient, and invariants of the Hessian. Analytic expressions for these counts are given to second order in the non-Gaussian correction, while a Monte Carlo method to compute them to arbitrary order is presented. Matching count statistics to these estimators is illustrated on fiducial non-Gaussian Planck data.

  4. Measuring primordial anisotropic correlators with CMB spectral distortions

    E-Print Network [OSTI]

    Maresuke Shiraishi; Michele Liguori; Nicola Bartolo; Sabino Matarrese

    2015-10-04

    We show that inflationary models with broken rotational invariance generate testable off-diagonal signatures in the correlation between the $\\mu$-type distortion and temperature fluctuations of the cosmic microwave background. More precisely, scenarios with a quadrupolar bispectrum asymmetry, usually generated by fluctuations of primordial vector fields, produce a nonvanishing $\\mu$-$T$ correlation when $|\\ell_1-\\ell_2|=2$. Since spectral distortions are sensitive to primordial fluctuations up to very small scales, a cosmic variance limited spectral distortion experiment can detect such effects with a high signal-to-noise ratio.

  5. Extragalactic foreground contamination in temperature-based CMB lens reconstruction

    SciTech Connect (OSTI)

    Osborne, Stephen J.; Hanson, Duncan; Doré, Olivier E-mail: dhanson@physics.mcgill.ca

    2014-03-01

    We discuss the effect of unresolved point source contamination on estimates of the CMB lensing potential, from components such as the thermal Sunyaev-Zel'dovich effect, radio point sources, and the Cosmic Infrared Background. We classify the possible trispectra associated with such source populations, and construct estimators for the amplitude and scale-dependence of several of the major trispectra. We show how to propagate analytical models for these source trispectra to biases for lensing. We also construct a ''source-hardened'' lensing estimator which experiences significantly smaller biases when exposed to unresolved point sources than the standard quadratic lensing estimator. We demonstrate these ideas in practice using the sky simulations of Sehgal et al., for cosmic-variance limited experiments designed to mimic ACT, SPT, and Planck. We find that for radio sources and SZ the bias is significantly reduced, but for CIB it is essentially unchanged. However, by using the high-frequency, all-sky CIB measurements from Planck and Herschel it may be possible to suppress this contribution.

  6. Background & Publications

    E-Print Network [OSTI]

    Home Background & Projects Calendar Publications Staff Directory Station Videos Links Search to pit. Harvest is expected to continue through this week. Balaton fruit set is light, and harvest abandon some sweet cherry blocks. Brown MAES Home | Field Stations | Station Home | Publications | Fruit

  7. Background & Publications

    E-Print Network [OSTI]

    Home Background & Projects Calendar Publications Staff Directory Station Videos Links Search Home | Field Stations | Station Home | Publications | FruitNet Weekly Report GROWING DEGREE DAY is still relatively light, probably due to few wetting periods during early shoot growth. Sun scald

  8. A perspective on the CMB acoustic peak

    E-Print Network [OSTI]

    T. A. Marriage

    2002-03-11

    CMB angular spectrum measurements suggest a flat universe. This paper clarifies the relation between geometry and the spherical harmonic index of the first acoustic peak ($\\ell_{peak}$). Numerical and analytic calculations show that $\\ell_{peak}$ is approximately a function of $\\Omega_K/\\Omega_M$ where $\\Omega_K$ and $\\Omega_M$ are the curvature ($\\Omega_K > 0$ implies an open geometry) and mass density today in units of critical density. Assuming $\\Omega_K/\\Omega_M \\ll 1$, one obtains a simple formula for $\\ell_{peak}$, the derivation of which gives another perspective on the widely-recognized $\\Omega_M$-$\\Omega_\\Lambda$ degeneracy in flat models. This formula for near-flat cosmogonies together with current angular spectrum data yields familiar parameter constraints.

  9. The full squeezed CMB bispectrum from inflation

    E-Print Network [OSTI]

    Antony Lewis

    2012-06-19

    The small-scale CMB temperature we observe on the sky is modulated by perturbations that were super-horizon at recombination, giving differential focussing and lensing that generate a non-zero bispectrum even for single-field inflation where local physics is identical. Understanding this signal is important for primordial non-Gaussianity studies and also parameter constraints from the CMB lensing bispectrum signal. Because of cancellations individual effects can appear larger or smaller than they are in total, so a full analysis may be required to avoid biases. I relate angular scales on the sky to physical scales at recombination using the optical equations, and give full-sky results for the large-scale adiabatic temperature bispectrum from Ricci focussing (expansion of the ray bundle), Weyl lensing (convergence and shear), and temperature redshift modulations of small-scale power. The delta N expansion of the beam is described by the constant temperature 3-curvature, and gives a nearly-observable version of the consistency relation prediction from single-field inflation. I give approximate arguments to quantify the likely importance of dynamical effects, and argue that they can be neglected for modulation scales l <~ 100, which is sufficient for lensing studies and also allows robust tests of local primordial non-Gaussianity using only the large-scale modulation modes. For accurate numerical results early and late-time ISW effects must be accounted for, though I confirm that the late-time non-linear Rees-Sciama contribution is negligible compared to other more important complications. The total corresponds to f_NL ~ 7 for Planck-like temperature constraints and f_NL ~ 11 for cosmic-variance limited data to lmax=2000. Temperature lensing bispectrum estimates are affected at the 0.2 sigma level by Ricci focussing, and up to 0.5 sigma with polarization.

  10. CMB Distortions from Damping of Acoustic Waves Produced by Cosmic Strings

    E-Print Network [OSTI]

    Hiroyuki Tashiro; Eray Sabancilar; Tanmay Vachaspati

    2013-08-20

    We study diffusion damping of acoustic waves in the photon-baryon fluid due to cosmic strings, and calculate the induced $\\mu$- and $y$-type spectral distortions of the cosmic microwave background. For cosmic strings with tension within current bounds, their contribution to the spectral distortions is subdominant compared to the distortions from primordial density perturbations.

  11. Gun Injection into a Microwave Plasma J. C. Sprott

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    Gun Injection into a Microwave Plasma by J. C. Sprott May, 1970 Plasma Studies University high densities by rapid pulsed gun injection. TIlis no te describes measurements made -Cwo years ago in which a gun plasma was injected into a background microwave plasma of variable density in the toroidal

  12. Microwave Radiometer (MWR) Handbook

    SciTech Connect (OSTI)

    Morris, VR

    2006-08-01

    The Microwave Radiometer (MWR) provides time-series measurements of column-integrated amounts of water vapor and liquid water. The instrument itself is essentially a sensitive microwave receiver. That is, it is tuned to measure the microwave emissions of the vapor and liquid water molecules in the atmosphere at specific frequencies.

  13. High brightness microwave lamp

    DOE Patents [OSTI]

    Kirkpatrick, Douglas A.; Dolan, James T.; MacLennan, Donald A.; Turner, Brian P.; Simpson, James E.

    2003-09-09

    An electrodeless microwave discharge lamp includes a source of microwave energy, a microwave cavity, a structure configured to transmit the microwave energy from the source to the microwave cavity, a bulb disposed within the microwave cavity, the bulb including a discharge forming fill which emits light when excited by the microwave energy, and a reflector disposed within the microwave cavity, wherein the reflector defines a reflective cavity which encompasses the bulb within its volume and has an inside surface area which is sufficiently less than an inside surface area of the microwave cavity. A portion of the reflector may define a light emitting aperture which extends from a position closely spaced to the bulb to a light transmissive end of the microwave cavity. Preferably, at least a portion of the reflector is spaced from a wall of the microwave cavity. The lamp may be substantially sealed from environmental contamination. The cavity may include a dielectric material is a sufficient amount to require a reduction in the size of the cavity to support the desired resonant mode.

  14. Microwave hemorrhagic stroke detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA)

    2007-06-05

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  15. Microwave hemorrhagic stroke detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA)

    2002-01-01

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stroke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  16. CMB anisotropy power spectrum using linear combinations of WMAP maps Rajib Saha,1,2,3

    E-Print Network [OSTI]

    Souradeep, Tarun

    CMB anisotropy power spectrum using linear combinations of WMAP maps Rajib Saha,1,2,3 Simon Prunet year WMAP data by Saha et al. 2006. All previous estimates of the power spectrum of the CMB are based

  17. First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

    E-Print Network [OSTI]

    C. Bennett; R. S. Hill; G. Hinshaw; M. R. Nolta; N. Odegard; L. Page; D. N. Spergel; J. L. Weiland; E. L. Wright; M. Halpern; N. Jarosik; A. Kogut; M. Limon; S. S. Meyer; G. S. Tucker; E. Wollack

    2003-06-05

    Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to remove foreground emission from the WMAP data is examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We construct a model of the Galactic emission components. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (beta ~ -2.5) near star-forming regions, especially in the plane, and steepest (beta ~ -3) in the halo. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to beta < -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with beta ~ 2.2. Microwave and H alpha measurements of the ionized gas agree. Spinning dust emission is limited to < ~5% of the Ka-band foreground emission. A catalog of 208 point sources is presented. Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 +- 1.4) 10^{-3} microK^2 sr at Q-band and negligible levels at V-band and W-band.

  18. CMB hemispherical asymmetry: long mode modulation and non-Gaussianity

    SciTech Connect (OSTI)

    Namjoo, Mohammad Hossein; Baghram, Shant; Firouzjahi, Hassan; Abolhasani, Ali Akbar E-mail: abolhasani@ipm.ir E-mail: firouz@ipm.ir

    2014-08-01

    The observed hemispherical asymmetry in CMB map can be explained by modulation from a long wavelength super horizon mode which non-linearly couples to the CMB modes. We address the criticism in [1] about the role of non-Gaussianities in squeezed and equilateral configurations in generating hemispherical asymmetry from the long mode modulation. We stress that the modulation is sensitive to the non-Gaussianity in the squeezed limit. In addition, we demonstrate the validity of our approach in providing a consistency condition relating the amplitude of dipole asymmetry to f{sub NL} in the squeezed limit.

  19. The clustering of merging star-forming haloes: dust emission as high frequency arcminute CMB foreground

    E-Print Network [OSTI]

    Righi, M; Sunyaev, R

    2007-01-01

    Future observations of CMB anisotropies will be able to probe high multipole regions of the angular power spectrum, corresponding to a resolution of a few arcminutes. Dust emission from merging haloes is one of the foregrounds that will affect such very small scales. We estimate the contribution to CMB angular fluctuations from objects which are bright in the sub-millimeter band due to intense star formation bursts following merging episodes. We also consider the effect of the intergalactic dust expelled from galaxies by strong winds and AGN activity. We base our approach on the Lacey-Cole merger model and on the Kennicutt relation which connects the star formation rate in galaxies with their infrared luminosity. We set the free parameters of the model in order to not exceed the SCUBA source counts, the Madau plot of star formation rate in the universe and COBE/FIRAS data on the intensity of the sub-millimeter cosmic background radiation. We show that the angular power spectrum arising from the distribution o...

  20. Filter!Demonstration Microwave!Office

    E-Print Network [OSTI]

    Filter!Demonstration in Microwave!Office muse #12;Objectives · Demonstrate!project!setup!in!Microwave

  1. Harmonic E/B decomposition for CMB polarization maps

    E-Print Network [OSTI]

    Antony Lewis

    2004-07-15

    The full sky cosmic microwave background polarization field can be decomposed into 'electric' (E) and 'magnetic' (B) components that are signatures of distinct physical processes. We give a general construction that achieves separation of E and B modes on arbitrary sections of the sky at the expense of increasing the noise. When E modes are present on all scales the separation of all of the B signal is no longer possible: there are inevitably ambiguous modes that cannot be separated. We discuss the practicality of performing E/B decomposition on large scales with realistic non-symmetric sky-cuts, and show that separation on large scales is possible by retaining only the well supported modes. The large scale modes potentially contain a great deal of useful information, and E/B separation at the level of the map is essential for clean detection of B without confusion from cosmic variance due to the E signal. We give simple matrix manipulations for creating pure E and B maps of the large scale signal for general sky cuts. We demonstrate that the method works well in a realistic case and give estimates of the performance with data from the Planck satellite. In the appendix we discuss the simple analytic case of an azimuthally symmetric cut, and show that exact E/B separation is possible on an azimuthally symmetric cut with a finite number of non-intersecting circular cuts around foreground sources.

  2. Constraints on dark matter annihilation from CMB observations before Planck

    SciTech Connect (OSTI)

    Lopez-Honorez, Laura [Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C., E-mail: llopezho@vub.ac.be, E-mail: omena@ific.uv.es, E-mail: sergio.palomares.ruiz@ist.utl.pt, E-mail: vincent@ific.uv.es [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de València, Apartado de Correos 22085, E-46071 Valencia (Spain)

    2013-07-01

    We compute the bounds on the dark matter (DM) annihilation cross section using the most recent Cosmic Microwave Background measurements from WMAP9, SPT'11 and ACT'10. We consider DM with mass in the MeV–TeV range annihilating 100% into either an e{sup +}e{sup ?} or a ?{sup +}?{sup ?} pair. We consider a realistic energy deposition model, which includes the dependence on the redshift, DM mass and annihilation channel. We exclude the canonical thermal relic abundance cross section ((?v) = 3 × 10{sup ?26}cm{sup 3}s{sup ?1}) for DM masses below 30 GeV and 15 GeV for the e{sup +}e{sup ?} and ?{sup +}?{sup ?} channels, respectively. A priori, DM annihilating in halos could also modify the reionization history of the Universe at late times. We implement a realistic halo model taken from results of state-of-the-art N-body simulations and consider a mixed reionization mechanism, consisting on reionization from DM as well as from first stars. We find that the constraints on DM annihilation remain unchanged, even when large uncertainties on the halo model parameters are considered.

  3. Variable frequency microwave heating apparatus

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

    1999-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  4. The Cosmic Microwave Background: Ringing in the New Cosmology

    E-Print Network [OSTI]

    Hu, Wayne

    · Without inflation, fluctuations must be generated at intermediate times · Like drilling holes i principle become the seeds of structure today · Can structure originate at intermediate times and provide

  5. Constraints on Cosmology from the Cosmic Microwave Background Power

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collider Tests ofOExperiments (Journal Article) |throughSpectrum of

  6. Constraints on Cosmology from the Cosmic Microwave Background Power

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collider Tests ofOExperiments (Journal Article) |throughSpectrum

  7. Constraints on cosmology from the cosmic microwave background power

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collider Tests ofOExperiments (Journal Article)Fermi Largespectrum

  8. A MEASUREMENT OF SECONDARY COSMIC MICROWAVE BACKGROUND ANISOTROPIES FROM

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnicalInformation4563 LLNL Small-scaleCoherent LightNetworks|Article) |

  9. George Smoot, Blackbody, and Anisotropy of the Cosmic Microwave Background

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFESOpportunities NuclearlongGeneral

  10. Microwave ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Reijonen, Jani; Thomae, Rainer W.

    2005-07-26

    A compact microwave ion source has a permanent magnet dipole field, a microwave launcher, and an extractor parallel to the source axis. The dipole field is in the form of a ring. The microwaves are launched from the middle of the dipole ring using a coaxial waveguide. Electrons are heated using ECR in the magnetic field. The ions are extracted from the side of the source from the middle of the dipole perpendicular to the source axis. The plasma density can be increased by boosting the microwave ion source by the addition of an RF antenna. Higher charge states can be achieved by increasing the microwave frequency. A xenon source with a magnetic pinch can be used to produce intense EUV radiation.

  11. Microwaves and Chemistry: The Catalysis of an Exciting Marriage 

    E-Print Network [OSTI]

    Wan, J.

    1992-01-01

    hydrocarbon oxidations to environmental technology will be illustrated. BACKGROUND The concept of using microwaves as an energy source for chemical reactions has only recently been appreciated. Part of the reason for this has been the bias of chemists... our first major success in cracking methane to ethylene and hydrogen [1,2], lhe destruction of chlorinated hydrocarbons [3,4], the hydrodesulfurization of hydrocracked pitch [5], and the microwave treatment of some Alberta oil sands and bitumens...

  12. Microwave thawing apparatus and method

    DOE Patents [OSTI]

    Fathi, Zakaryae; Lauf, Robert J.; McMillan, April D.

    2004-06-01

    An apparatus for thawing a frozen material includes: a microwave energy source; a microwave applicator which defines a cavity for applying microwave energy from the microwave source to a material to be thawed; and a shielded region which is shielded from the microwave source, the shielded region in fluid communication with the cavity so that thawed material may flow from the cavity into the shielded region.

  13. BBN And The CMB Constrain Neutrino Coupled Light WIMPs

    E-Print Network [OSTI]

    Kenneth M. Nollett; Gary Steigman

    2015-02-12

    (abridged) In the presence of a light WIMP (mass m_chi 35 MeV, equivalent to no light WIMP at all. All masses below 4--9 MeV (depending on spin) are excluded. Without any light WIMP, BBN alone prefers Delta N_nu = 0.50 +- 0.23, favoring neither Delta N_nu = 0, nor a fully thermalized sterile neutrino (Delta N_nu = 1). This result is consistent with the CMB constraint, N_eff = 3.30 +- 0.27, limiting "new physics" between BBN and recombination. Combining BBN and CMB data gives Delta N_nu = 0.35 +- 0.16 and N_eff = 3.40 +- 0.16; while BBN and the CMB combined require Delta N_nu > 0 at ~98% confidence, they disfavor Delta N_nu > 1 at > 99% confidence. Allowing a neutrino-coupled light WIMP extends the allowed range slightly downward for Delta N_nu and slightly upward for N_eff simultaneously, leaving best-fit values unchanged.

  14. Cosmological Avatars of the Landscape II: CMB and LSS Signatures

    E-Print Network [OSTI]

    R. Holman; Laura Mersini-Houghton; Tomo Takahashi

    2006-12-13

    This is the second paper in the series that confronts predictions of a model of the landscape with cosmological observations. We show here how the modifications of the Friedmann equation due to the decohering effects of long wavelength modes on the wavefunction of the Universe defined on the landscape leave unique signatures on the CMB spectra and large scale structure (LSS). We show that the effect of the string corrections is to suppress $\\sigma_8$ and the CMB $TT$ spectrum at large angles, thereby bringing WMAP and SDSS data for $\\sigma_8$ into agreement. We find interesting features imprinted on the matter power spectrum $P(k)$: power is suppressed at large scales indicating the possibility of primordial voids competing with the ISW effect. Furthermore, power is enhanced at structure and substructure scales, $k\\simeq 10^{-2-0} h~{\\rm Mpc}^{-1}$. Our smoking gun for discriminating this proposal from others with similar CMB and LSS predictions come from correlations between cosmic shear and temperature anisotropies, which here indicate a noninflationary channel of contribution to LSS, with unique ringing features of nonlocal entanglement displayed at structure and substructure scales.

  15. Microwave enhanced silica encapsulation of magnetic nanoparticles

    E-Print Network [OSTI]

    Park, Jeong Chan; Gilbert, Dustin A; Liu, Kai; Louie, Angelique Y.

    2012-01-01

    rapidly by using an ef?cient microwave irradiation method.8449 PAPER www.rsc.org/materials Microwave enhanced silicaachieved within 10 min via microwave irradiation after phase

  16. Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources

    E-Print Network [OSTI]

    P. Giommi; M. Capalbi; E. Cavazzuti; S. Colafrancesco; A. Cucchiara; A. Falcone; J. Kennea; R. Nesci; M. Perri; G. Tagliaferri; A. Tramacere; G. Tosti; A. J. Blustin; G. Branduardi-Raymont; D. N. Burrows; G. Chincarini; A. J. Dean; N. Gehrels; H. Krimm; F. Marshall; A. M. Parsons; B. Zhang

    2007-03-07

    Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year) were never reported before as X-ray sources. We present here the results of 41 Swift observations which led to the detection of all these 23 blazars in the 0.3-10 keV band. We conclude that all micro-wave selected blazars are X-ray emitters and that the distribution of the micro-wave to X-ray spectral slope $\\alpha_{mu x}$ of LBL blazars is very narrow, confirming that the X-ray flux of most blazars is a very good estimator of their micro-wave emission. The X-ray spectral shape of all the objects that were observed long enough to allow spectral analysis is flat and consistent with inverse Compton emission within the commonly accepted view where the radiation from blazars is emitted in a Sychrotron-Inverse-Compton scenario. We predict that all blazars and most radio galaxies above the sensitivity limit of the WMAP and of the Planck CMB missions are X-ray sources detectable by the present generation of X-ray satellites. An hypothetical all-sky soft X-ray survey with sensitivity of approximately $10^{-15}$ erg/s would be crucial to locate and remove over 100,000 blazars from CMB temperature and polarization maps and therefore accurately clean the primordial CMB signal from the largest population of extragalactic foreground contaminants.

  17. The White Mountain Polarimeter Telescope and an Upper Limit on CMB Polarization

    E-Print Network [OSTI]

    Alan R. Levy; Rodrigo Leonardi; Markus Ansmann; Marco Bersanelli; Jeffery Childers; Terrence D. Cole; Ocleto D'Arcangelo; G. Vietor Davis; Philip M. Lubin; Joshua Marvil; Peter R. Meinhold; Gerald Miller; Hugh O`Neill; Fabrizio Stavola; Nathan C. Stebor; Peter T. Timbie; Maarten van der Heide; Fabrizio Villa; Thyrso Villela; Brian D. Williams; Carlos A. Wuensche

    2008-04-23

    The White Mountain Polarimeter (WMPol) is a dedicated ground-based microwave telescope and receiver system for observing polarization of the Cosmic Microwave Background. WMPol is located at an altitude of 3880 meters on a plateau in the White Mountains of Eastern California, USA, at the Barcroft Facility of the University of California White Mountain Research Station. Presented here is a description of the instrument and the data collected during April through October 2004. We set an upper limit on $E$-mode polarization of 14 $\\mu\\mathrm{K}$ (95% confidence limit) in the multipole range $170<\\ell<240$. This result was obtained with 422 hours of observations of a 3 $\\mathrm{deg}^2$ sky area about the North Celestial Pole, using a 42 GHz polarimeter. This upper limit is consistent with $EE$ polarization predicted from a standard $\\Lambda$-CDM concordance model.

  18. Light WIMPs, Equivalent Neutrinos, BBN, and the CMB

    E-Print Network [OSTI]

    Gary Steigman; Kenneth M. Nollett

    2014-01-21

    Recent updates to the observational determinations of the primordial abundances of helium and deuterium are compared to the predictions of BBN to infer the universal ratio of baryons to photons (or, the present Universe baryon mass density parameter Omega_B h^2), as well as to constrain the effective number of neutrinos (N_eff) and the number of equivalent neutrinos (Delta N_nu). These BBN results are compared to those derived independently from the Planck CMB data. In the absence of a light WIMP (chi), N_eff = 3.05(1 + Delta N_nu/3). In this case, there is excellent agreement between BBN and the CMB, but the joint fit finds that Delta N_nu = 0.40 +/- 0.17, disfavoring standard big bang nucleosynthesis (SBBN: Delta N_nu = 0) at 2.4 sigma, as well as a sterile neutrino (Delta N_nu = 1) at 3.5 sigma. In the presence of a light WIMP, the relation between N_eff and Delta N_nu depends on the WIMP mass, leading to degeneracies among N_eff, Delta N_nu, and m_chi. The complementary and independent BBN and CMB data can break some of these degeneracies. Depending on the nature of the light WIMP (Majorana or Dirac fermion, real or complex scalar) the joint BBN + CMB analyses set a lower bound to m_chi in the range from 0.5 to 5 MeV, and they identify best fit values for m_chi in the range from 5 to 10 MeV. The joint BBN + CMB analyses find a best fit value for the number of equivalent neutrinos, Delta N_nu = 0.65, nearly independent of the nature of the WIMP. The best fit still disfavors the absence of dark radiation (Delta N_nu = 0 at 95% confidence), while allowing for the presence of a sterile neutrino (Delta N_nu = 1 at less than 1 sigma). For all cases considered here, the lithium problem persists. These results, presented at the 2013 Rencontres de l'Observatoire de Paris - ESO Workshop, are based on Nollett & Steigman 2013 (arXiv:1312.5725 [astro-ph.CO]).

  19. Microwave Mapping As a Possible New Diagnostic Tool for LargeScale Solar Magnetic Fields

    E-Print Network [OSTI]

    Petrovay, Kristóf

    Microwave Mapping As a Possible New Diagnostic Tool for Large­Scale Solar Magnetic Fields M of microwave maps in the study of weak large­scale solar magnetic fields is discussed. Our knowledge of the large­scale solar background magnetic fields is limited by the circumstance that magnetograph

  20. IDENTIFYING THE RADIO BUBBLE NATURE OF THE MICROWAVE HAZE

    SciTech Connect (OSTI)

    Dobler, Gregory, E-mail: dobler@kitp.ucsb.edu [Kavli Institute for Theoretical Physics, University of California, Santa Barbara Kohn Hall, Santa Barbara, CA 93106 (United States)

    2012-11-20

    Using seven-year data from the Wilkinson Microwave Anisotropy Probe, I identify a sharp 'edge' in the microwave haze at high southern Galactic latitude (-55 Degree-Sign < b < -35 Degree-Sign ) that is spatially coincident with the southern edge of the 'Fermi haze/bubbles'. This finding proves conclusively that the edge in the gamma rays is real (and not a processing artifact), demonstrates explicitly that the microwave haze and the gamma-ray bubbles are indeed the same structure observed at multiple wavelengths, and strongly supports the interpretation of the microwave haze as a separate component of Galactic synchrotron (likely generated by a transient event) as opposed to a simple variation of the spectral index of disk synchrotron. In addition, combining these data sets allows for the first determination of the magnetic field within a radio bubble using microwaves and gamma rays by taking advantage of the fact that the inverse Compton gamma rays are primarily generated by scattering of cosmic microwave background photons at these latitudes, thus minimizing uncertainty in the target radiation field. Assuming uniform volume emissivity, I find that the magnetic field within the southern Galactic microwave/gamma-ray bubble is {approx}5 {mu}G above 6 kpc off of the Galactic plane.

  1. Microwave and Radio Frequency Workshop

    Broader source: Energy.gov [DOE]

    At the Microwave and Radio Frequency Workshop (held in Long Beach, CA, on July 25, 2012), academic and industry experts discussed the existing and emerging electrotechnologies – such as microwave ...

  2. PHOTOCHEMISTRY IN THE MICROWAVE FIELD

    E-Print Network [OSTI]

    Cirkva, Vladimir

    . EDLs Hg-EDLs: I2- and P-EDLs S-EDL vs. solar radiation flux Literature: 1. P. Klán V. Církva, MicrowavePHOTOCHEMISTRY IN THE MICROWAVE FIELD P. Müller, J. Literák, V. Církva, Petr Klán* Department distinctive kinds of electromagnetic radiation, microwave (MW) and ultraviolet/visible: energy of MW radiation

  3. CMB quadrupole suppression: II. The early fast roll stage

    E-Print Network [OSTI]

    D. Boyanovsky; H. J. de Vega; N. G. Sanchez

    2007-03-12

    Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established.Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of efolds N_{tot} ~ 59, there is a 10-20% suppression of the CMB quadrupole and about 2-4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l^2. The suppression is much smaller for N_{tot} > 59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound N_{tot} ~ 59.

  4. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  5. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  6. Improved Cosmological Parameter Constraints from CMB and H(z) Data

    E-Print Network [OSTI]

    Daniel G. Figueroa; Licia Verde; Raul Jimenez

    2008-10-27

    We discuss the cosmological degeneracy between the Hubble parameter H(z), the age of the universe and cosmological parameters describing simple variations from the minimal LCDM model. We show that independent determinations of the Hubble parameter H(z) such as those recently provided by Simon et al., Phys. Rev. D 71 (2005) 123001, combined with Cosmic Microwave Background data, can provide stringent constraints on possible deviations from the LCDM model. In particular we find that this data combination constrains at the 68% (95%) confidence level the following parameters: sum of the neutrino masses < 0.5 (1.0) eV, number of relativistic neutrino species N_rel = 4.1^{+0.4}_{-0.9} (^{+1.1}_{-1.5}), dark energy equation of state parameter w = -0.95 +- 0.17 (+- 0.32), and curvature \\Omega_k = 0.002 +- 0.006 (+- 0.014), in excellent agreement with dataset combinations involving Cosmic Microwave Background, Supernovae and Baryon Acoustic Oscillations. This offers a valuable consistency check for systematic errors.

  7. Evidence of cross-correlation between the CMB lensing and the gamma-ray sky

    E-Print Network [OSTI]

    N. Fornengo; L. Perotto; M. Regis; S. Camera

    2015-03-02

    We report the measurement of the angular power spectrum of cross-correlation between the unresolved component of the Fermi-LAT gamma-ray sky-maps and the CMB lensing potential map reconstructed by the Planck satellite. The matter distribution in the Universe determines the bending of light coming from the last scattering surface. At the same time, the matter density drives the growth history of astrophysical objects, including their capability at generating non-thermal phenomena, which in turn give rise to gamma-ray emissions. The Planck lensing map provides information on the integrated distribution of matter, while the integrated history of gamma-ray emitters is imprinted in the Fermi-LAT sky maps. We report here the first evidence of their correlation. We find that the multipole dependence of the cross-correlation measurement is in agreement with current models of the gamma-ray luminosity function for AGN and star forming galaxies, with a statistical evidence of 3.0$\\sigma$. Moreover, its amplitude can in general be matched only assuming that these extra-galactic emitters are also the bulk contribution of the measured isotopic gamma-ray background (IGRB) intensity. This leaves little room for a big contribution from galactic sources to the IGRB measured by Fermi-LAT, pointing toward a direct evidence of the extragalactic origin of the IGRB.

  8. On the dark energy rest frame and the CMB

    E-Print Network [OSTI]

    Jose Beltran Jimenez; Antonio L. Maroto

    2008-12-11

    Dark energy is usually parametrized as a perfect fluid with negative pressure and a certain equation of state. Besides, it is supposed to interact very weakly with the rest of the components of the universe and, as a consequence, there is no reason to expect it to have the same large-scale rest frame as matter and radiation. Thus, apart from its equation of state $w$ and its energy density $\\Omega_{DE}$ one should also consider its velocity as a free parameter to be determined by observations. This velocity defines a cosmological preferred frame, so the universe becomes anisotropic and, therefore, the CMB temperature fluctuations will be affected, modifying mainly the dipole and the quadrupole.

  9. Contribution of domain wall networks to the CMB power spectrum

    E-Print Network [OSTI]

    Lazanu, A; Shellard, E P S

    2015-01-01

    We use three domain wall simulations from the radiation era to the late time dark energy domination era based on the PRS algorithm to calculate the energy-momentum tensor components of domain wall networks in an expanding universe. Unequal time correlators in the radiation, matter and cosmological constant epochs are calculated using the scaling regime of each of the simulations. The CMB power spectrum of a network of domain walls is determined. The first ever quantitative constraint for the domain wall surface tension is obtained using a Markov chain Monte Carlo method; an energy scale of domain walls of 0.93 MeV, which is close but below the Zel'dovich bound, is determined.

  10. The effective gravitational decoupling between dark matter and the CMB

    SciTech Connect (OSTI)

    Voruz, Luc; Lesgourgues, Julien; Tram, Thomas, E-mail: luc.voruz@gmail.com, E-mail: Julien.Lesgourgues@cern.ch, E-mail: thomas.tram@epfl.ch [Institut de Théorie des Phénomènes Physiques, École Polytechnique Fédérale de Lausanne, CH-1015, Lausanne (Switzerland)

    2014-03-01

    e present a detailed and self-contained analytical derivation of the evolution of sub-horizon cosmological perturbations before decoupling, based on previous work by S. Weinberg. These solutions are valid in the minimal ?CDM scenario, to first order in perturbation theory, in the tight-coupling limit and neglecting neutrino shear stress. We compare them to exact numerical solutions computed by a Boltzmann code, and we find the two to be in very good agreement. The analytic solutions show explicitly that CDM and the baryon-photon fluid effectively behave as separate self-gravitating fluids until the epoch of baryon drag. This in turn leads to the surprising conclusion that the CMB is much less sensitive to the clustering properties of minimally coupled Dark Matter models than what would be naively expected.

  11. FUSING MICROWAVE RADAR AND MICROWAVE-INDUCED THERMOACOUSTICS FOR BREAST CANCER DETECTION

    E-Print Network [OSTI]

    FUSING MICROWAVE RADAR AND MICROWAVE-INDUCED THERMOACOUSTICS FOR BREAST CANCER DETECTION Evgeny in the microwave range. Microwave-radar and microwave-induced thermoacoustic methods both struggle when-induced thermoacoustic (MIT) methods measure and process the acoustic signals induced by differential microwave heating

  12. Microwave solidification project overview

    SciTech Connect (OSTI)

    Sprenger, G.

    1993-01-01

    The Rocky Flats Plant Microwave Solidification Project has application potential to the Mixed Waste Treatment Project and the The Mixed Waste Integrated Program. The technical areas being addressed include (1) waste destruction and stabilization; (2) final waste form; and (3) front-end waste handling and feed preparation. This document covers need for such a program; technology description; significance; regulatory requirements; and accomplishments to date. A list of significant reports published under this project is included.

  13. High Energy Density Microwaves

    SciTech Connect (OSTI)

    Phillips, R.M. [Stanford Linear Accelerator Center, Stanford, CA 94309 (United States)

    1999-04-01

    These proceedings represent papers presented at the RF98 Workshop entitled `High Energy Density Microwaves` held in California in October, 1998. The topics discussed were predominantly accelerator{minus}related. The Workshop dealt, for the most part, with the generation and control of electron beams, the amplification of RF signals, the design of mode converters, and the effect of very high RF field gradients. This Workshop was designed to address the concerns of the microwave tube industry worldwide, the plasma physicists who deal with very high beam currents and gigawatts of RF power, and researchers in accelerator centers around the world. Papers were presented on multibeam klystrons, gyrotron development, plasmas in microwave tubes, RF breakdown, and alternatives to conventional linear coliders at 1 TeV and above. The Workshop was partially sponsored by the US Department of Energy. There were 46 papers presented at the conference,out of which 19 have been abstracted for the Energy,Science and Technology database.(AIP)

  14. Detectability of CMB tensor B modes via delensing with weak lensing galaxy surveys

    E-Print Network [OSTI]

    Laura Marian; Gary M. Bernstein

    2007-10-15

    We analyze the possibility of delensing CMB polarization maps using foreground weak lensing (WL) information. We build an estimator of the CMB lensing potential out of optimally combined projected potential estimators to different source redshift bins. Our estimator is most sensitive to the redshift depth of the WL survey, less so to the shape noise level. Estimators built using galaxy surveys like LSST and SNAP yield a 30-50% reduction in the lensing B-mode power. We illustrate the potential advantages of a 21-cm survey by considering a fiducial WL survey for which we take the redshift depth zmax and the effective angular concentration of sources n as free parameters. For a noise level of 1 muK arcmin in the polarization map itself, as projected for a CMBPol experiment, and a beam with FWHM=10 arcmin, we find that going to zmax=20 at n=100 gal/sqarcmin yields a delensing performance similar to that of a quadratic lensing potential estimator applied to small-scale CMB maps: the lensing B-mode contamination is reduced by almost an order of magnitude. In this case, there is also a reduction by a factor of ~4 in the detectability threshold of the tensor B-mode power. At this CMB noise level, there is little gain from sources with zmax>20. The delensing gains are lost if the CMB beam exceeds ~20 arcmin. The delensing efficiency and useful zmax depend acutely on the CMB map noise level, but beam sizes below 10 arcmin do not help. Delensing via foreground sources does not require arcminute-resolution CMB observations, a substantial practical advantage over the use of CMB observables for delensing.

  15. Microwave sintering of multiple articles

    DOE Patents [OSTI]

    Blake, Rodger D. (Santa Fe, NM); Katz, Joel D. (Los Alamos, NM)

    1993-01-01

    Apparatus and method for producing articles of alumina and of alumina and silicon carbide in which the articles are sintered at high temperatures using microwave radiation. The articles are placed in a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.

  16. Neutral hydrogen structures trace dust polarization angle: Implications for the interstellar medium and CMB foregrounds

    E-Print Network [OSTI]

    Clark, S E; Peek, J E G; Putman, M E; Babler, B L

    2015-01-01

    Using high-resolution data from the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) survey, we show that linear structure in Galactic neutral hydrogen (HI) correlates with the magnetic field orientation implied by Planck 353 GHz polarized dust emission. The structure of the neutral interstellar medium is more tightly coupled to the magnetic field than previously known. At high Galactic latitudes, where the Planck data are noise-dominated, the HI data provide an independent constraint on the Galactic magnetic field orientation, and hence the local dust polarization angle. We detect strong cross-correlations between template maps constructed from estimates of dust intensity combined with either HI-derived angles, starlight polarization angles, or Planck 353 GHz angles. The HI data thus provide a new tool in the search for inflationary gravitational wave B-mode polarization in the cosmic microwave background, which is currently limited by dust foreground contamination.

  17. Possible Evidence for Planck-Scale Resonant Particle Production during Inflation from the CMB Power Spectrum

    E-Print Network [OSTI]

    Mathews, G J; Ichiki, K; Kajino, T

    2015-01-01

    The power spectrum of the cosmic microwave background from both the Planck and WMAP data exhibits a slight dip in for multipoles in the range of l=10-30. We show that such a dip could be the result of resonant creation of a massive particle that couples to the inflaton field. For our best-fit models, epochs of resonant particle creation reenters the horizon at wave numbers of k* ~ 0.00011 (h/Mpc). The amplitude and location of these features correspond to the creation of a number of degenerate fermion species of mass ~ 15 times the planck mass during inflation with a coupling constant between the inflaton field and the created fermion species of near unity. Although the evidence is marginal, if this interpretation is correct, this could be one of the first observational hints of new physics at the Planck scale.

  18. CMB radiation power spectrum in CDM open universes up to 2nd order perturbations

    E-Print Network [OSTI]

    Jose L. Sanz; Enrique Martinez-Gonzalez; Laura Cayon; Joseph Silk; Naoshi Sugiyama

    1996-02-28

    A second--order perturbation theory approach is developed to calculate temperature anisotropies in the cosmic microwave background. Results are given for open universes and fluctuations corresponding to CDM models with either Harrison-Zeldovich (HZ) or Lyth-Stewart-Ratra-Peebles (LSRP) primordial energy--density fluctuation power spectrum. Our perturbation theory approach provides a distinctive multipole contribution as compared to the primary one, the amplitude of the effect being very dependent on normalization. For low--$\\Omega$ models, the contribution of the secondary multipoles to the radiation power spectrum is negligible both for standard recombination and reionized scenarios, with the 2--year COBE--DMR normalization. For a flat universe this contribution is $\\approx 0.1-10\\%$ depending on the reionization history of the universe and on the normalization of the power spectrum.

  19. PANDEMIC INFLUENZA background briefing

    E-Print Network [OSTI]

    Rambaut, Andrew

    , Dave Carr, David Lynn and Phil Green Transmission electron micrograph of Influenza A virus (WellcomePANDEMIC INFLUENZA background briefing Biomedicine Forum 5 November 2008 compiled by David Evans

  20. Cosmology with moving dark energy and the CMB quadrupole

    E-Print Network [OSTI]

    Jose Beltran Jimenez; Antonio L. Maroto

    2007-07-11

    We study the consequences of a homogeneous dark energy fluid having a non-vanishing velocity with respect to the matter and radiation large-scale rest frames. We consider homogeneous anisotropic cosmological models with four fluids (baryons, radiation, dark matter and dark energy) whose velocities can differ from each other. Performing a perturbative calculation up to second order in the velocities, we obtain the contribution of the anisotropies generated by the fluids motion to the CMB quadrupole and compare with observations. We also consider the exact problem for arbitrary velocities and solve the corresponding equations numerically for different dark energy models. We find that models whose equation of state is initially stiffer than radiation, as for instance some tracking models, are unstable against velocity perturbations, thus spoiling the late-time predictions for the energy densities. In the case of scaling models, the contributions to the quadrupole can be non-negligible for a wide range of initial conditions. We also consider fluids moving at the speed of light (null fluids) with positive energy and show that, without assuming any particular equation of state, they generically act as a cosmological constant at late times. We find the parameter region for which the models considered could be compatible with the measured (low) quadrupole.

  1. String Theory clues for the low-$\\ell$ CMB ?

    E-Print Network [OSTI]

    N. Kitazawa; A. Sagnotti

    2014-12-01

    "Brane Supersymmetry Breaking" is a peculiar string-scale mechanism that can unpair Bose and Fermi excitations in orientifold models. It results from the simultaneous presence, in the vacuum, of collections of D-branes and orientifolds that are not mutually BPS, and is closely tied to the scale of string excitations. It also leaves behind, for a mixing of dilaton and internal breathing mode, an exponential potential that is just too steep for a scalar to emerge from the initial singularity while descending it. As a result, in this class of models the scalar can generically bounce off the exponential wall, and this dynamics brings along, in the power spectrum, an infrared depression typically followed by a pre-inflationary peak. We elaborate on a possible link between this type of bounce and the low-$\\ell$ end of the CMB angular power spectrum. For the first 32 multipoles, one can reach a 50 % reduction in $\\chi^{\\,2}$ with respect to the standard $\\Lambda$CDM setting.

  2. Oscillations in the CMB from Axion Monodromy Inflation

    SciTech Connect (OSTI)

    Flauger, Raphael; McAllister, Liam; Pajer, Enrico; Westphal, Alexander; Xu, Gang; /Cornell U., Phys. Dept.

    2011-12-01

    We study the CMB observables in axion monodromy inflation. These well-motivated scenarios for inflation in string theory have monomial potentials over super-Planckian field ranges, with superimposed sinusoidal modulations from instanton effects. Such periodic modulations of the potential can drive resonant enhancements of the correlation functions of cosmological perturbations, with characteristic modulations of the amplitude as a function of wavenumber. We give an analytical result for the scalar power spectrum in this class of models, and we determine the limits that present data places on the amplitude and frequency of modulations. Then, incorporating an improved understanding of the realization of axion monodromy inflation in string theory, we perform a careful study of microphysical constraints in this scenario. We find that detectable modulations of the scalar power spectrum are commonplace in well-controlled examples, while resonant contributions to the bispectrum are undetectable in some classes of examples and detectable in others. We conclude that resonant contributions to the spectrum and bispectrum are a characteristic signature of axion monodromy inflation that, in favorable cases, could be detected in near-future experiments.

  3. Microwave hematoma detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA); Matthews, Dennis L. (Moss Beach, CA)

    2001-01-01

    The Microwave Hematoma Detector is a non-invasive device designed to detect and localize blood pooling and clots near the outer surface of the body. While being geared towards finding sub-dural and epi-dural hematomas, the device can be used to detect blood pooling anywhere near the surface of the body. Modified versions of the device can also detect pneumothorax, organ hemorrhage, atherosclerotic plaque in the carotid arteries, evaluate perfusion (blood flow) at or near the body surface, body tissue damage at or near the surface (especially for burn assessment) and be used in a number of NDE applications. The device is based on low power pulsed microwave technology combined with a specialized antenna, signal processing/recognition algorithms and a disposable cap worn by the patient which will facilitate accurate mapping of the brain and proper function of the instrument. The invention may be used for rapid, non-invasive detection of sub-dural or epi-dural hematoma in human or animal patients, detection of hemorrhage within approximately 5 cm of the outer surface anywhere on a patient's body.

  4. Microwave-driven ultraviolet light sources

    DOE Patents [OSTI]

    Manos, Dennis M. (Williamsburg, VA); Diggs, Jessie (Norfolk, VA); Ametepe, Joseph D. (Roanoke, VA)

    2002-01-29

    A microwave-driven ultraviolet (UV) light source is provided. The light source comprises an over-moded microwave cavity having at least one discharge bulb disposed within the microwave cavity. At least one magnetron probe is coupled directly to the microwave cavity.

  5. Gigatron microwave amplifier

    DOE Patents [OSTI]

    McIntyre, P.M.

    1993-07-13

    An electron tube for achieving high power at high frequency with high efficiency is described, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot there through for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

  6. Gigatron microwave amplifier

    DOE Patents [OSTI]

    McIntyre, Peter M. (611 Montclair, College Station, TX 77840)

    1993-01-01

    An electron tube for achieving high power at high frequency with high efficiency, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot therethrough for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

  7. CAMAC SYSTEM FOR COMPUTER CONTROL OF MICROWAVE SPECTROMETERS

    E-Print Network [OSTI]

    Zizka, G.

    2010-01-01

    of the 5th International Microwave Conference, Hamburg, WestBuscher, and B. Leskovar, "Microwave Absorption Coefficientsof Sulfur Dioxide Microwave Rotational Lines, J. o."

  8. Microwave-Assisted Ignition for Improved Internal Combustion Engine Efficiency

    E-Print Network [OSTI]

    DeFilippo, Anthony Cesar

    2013-01-01

    of Flame Speed by Intense Microwave Radiation. ” CombustionLimits of Gasoline Using a Microwave- Assisted Spark Plug. ”Krage, M. K. (1984) "Microwave Effects on Premixed Flames."

  9. MICROWAVE SPECTROMETER FOR THE DETECTION OF TRANSIENT GASEOUS SPECIES

    E-Print Network [OSTI]

    Kolbe, W.F.

    2011-01-01

    for Computer Control of Microwave Spectrometers, LBL-9276,and H. P. Broida, "Microwave Discharge Cavities Operating atJr. , and C. H. Townes, "Microwave Spectra of the Free

  10. Effects of Microwave Radiation on Selected Mechanical Properties of Silk

    E-Print Network [OSTI]

    Reed, Emily Jane

    2013-01-01

    coli and MRSA using microwave-induced argon plasma atof mycotoxins using microwave-induced argon plasma atClark and W. H. Sutton, "Microwave processing of materials,"

  11. RF and Microwave Amplifier Design With ESD Protection

    E-Print Network [OSTI]

    Lin, Lin

    2010-01-01

    Amplifier,” IEEE Trans. Microwave Theory and Techniques,Amplifier,” IEEE Trans. Microwave Theory and Techniques,for UWB Applications. ” Microwave and Optical Technology

  12. Integrated coherent receivers for high-linearity microwave photonic links

    E-Print Network [OSTI]

    2008-01-01

    down sampling of wideband microwave signals,” J. Lightw.tunable MMI coupler for microwave photonic circuits,” inReceivers for High-Linearity Microwave Photonic Links Anand

  13. Microwave Regenerated DPF for Auxiliary Power Units and Diesel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Microwave Regenerated DPF for Auxiliary Power Units and Diesel Hybrid Vehicles Microwave Regenerated DPF for Auxiliary Power Units and Diesel Hybrid Vehicles Microwave regeneration...

  14. Background & Projects Publications

    E-Print Network [OSTI]

    Home Background & Projects Calendar Publications Staff Directory Links Search MAES Home | Field Stations | Station Home | Publications | FruitNet Weekly Report Northern Michigan FruitNet 2006 Weekly vineyards. Side hedging and/or topping shoots will be needed to get light and air to the fruiting zone

  15. Microwave Meals in a Hurry. 

    E-Print Network [OSTI]

    Haggard, Marilyn A.

    1981-01-01

    Bulletin] Microwave Meals in a Hurry Marilyn A. Haggard* r- Mi, Nave ovens are time-savers for many busy Texans. Used at their optimum, they can be both time and energy savers. However, optimum use takes prac tice. Beginners should allow plenty... foods are being defrosted or cooked. Cook foods that require the same temperature set ting together. It makes preparation faster and saves energy. Study the following examples of organization and planning for microwave meals. Breakfast Orange...

  16. Quantum backgrounds and QFT

    E-Print Network [OSTI]

    Jae-Suk Park; John Terilla; Thomas Tradler

    2009-09-21

    We introduce the concept of a quantum background and a functor QFT. In the case that the QFT moduli space is smooth formal, we construct a flat quantum superconnection on a bundle over QFT which defines algebraic structures relevant to correlation functions in quantum field theory. We go further and identify chain level generalizations of correlation functions which should be present in all quantum field theories.

  17. ARM - Methane Background Information

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach HomepolarizationMeasurementsWarmingMethane Background

  18. LTS Background - Hanford Site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse Bergkamp Graduate student Subtask22Background About Us LTS Home Page LTS

  19. DNA sequencing using fluorescence background electroblotting membrane

    DOE Patents [OSTI]

    Caldwell, K.D.; Chu, T.J.; Pitt, W.G.

    1992-05-12

    A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through amino groups contained on the surface. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to the target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membranes may be reprobed numerous times. No Drawings

  20. Microwave heating apparatus and method

    DOE Patents [OSTI]

    Johnson, Andrew J. (Boulder, CO); Petersen, Robert D. (Thornton, CO); Swanson, Stephen D. (Brighton, CO)

    1990-01-01

    An apparatus is provided for heating and melting materials using microwave energy, and for permitting them to solidify. The apparatus includes a microwave energy source, a resonant cavity having an opening in its floor, a microwave energy choke encompassing the opening in the floor of the cavity, a metal container to hold the materials to be heated and melted, a turntable, and a lift-table. During operation, the combined action of the turntable and the lift-table position the metal container so that the top of the container is level with the floor of the cavity, is in substantial registration with the floor opening, and is encompassed by the microwave energy choke; thus, during operation, the interior of the container defines part of the resonant cavity. Additionally, a screw feeder, extending into the cavity and sheltered from microwave energy by a conveyor choke, may convey the materials to be heated to the container. Also, preferably, the floor of the resonant cavity may include perforatins, so that the offgases and dust generated in the apparatus may be removed from the resonant cavity by pulling outside air between the container choke and the exterior wall of the container into the resonant cavity and out from the cavity through the perforations.

  1. Microwave andTerahertz Generation Based on Photonically Assisted Microwave Frequency

    E-Print Network [OSTI]

    Yao, Jianping

    Microwave andTerahertz Generation Based on Photonically Assisted Microwave Frequency Twelvetupling Member, IEEE DOI: 10.1109/JPHOT.2010.2084993 1943-0655/$26.00 ©2010 IEEE #12;Microwave and Terahertz Generation Based on Photonically Assisted Microwave Frequency Twelvetupling With Large Tunability Wangzhe Li

  2. Bounds on QCD axion mass and primordial magnetic field from CMB $?$-distortion

    E-Print Network [OSTI]

    Damian Ejlli

    2015-08-19

    The oscillation of the CMB photons into axions can cause CMB spectral distortion in the presence of large scale magnetic field. With the COBE limit on the $\\mu$ parameter and a homogeneous magnetic field with strength $B\\lesssim 3.2$ nG at the horizon scale, an upper limit on the axion mass is found to be, $m_a\\lesssim 4.8\\times 10^{-5}$ eV for the KSVZ axion model. On the other hand, using the value of excluded axion mass $m_a\\simeq 3.5\\times 10^{-6}$ eV from the ADMX experiment together with the COBE bound on $\\mu$, is found $B\\simeq 46$ nG for the KSVZ axion model and $B\\simeq 130$ nG for DFSZ axion model, for a homogeneous magnetic field with coherence length at the present epoch $\\lambda_B\\simeq 1.3$ Mpc. Forecast on $B$ and $m_a$ for PIXIE/PRISM expected sensitivity on $\\mu$ are derived. If CMB $\\mu$ distortion would be detected by the future space missions PIXIE/PRISM and assuming that the strength of the large scale magnetic field is close to its canonical value, $B\\simeq 1-3$ nG, axions in the mass range $2\\, \\mu$eV - $3\\, \\mu$eV would be potential candidates of CMB $\\mu$-distortion.

  3. Bounds on QCD axion mass and primordial magnetic field from CMB $?$-distortion

    E-Print Network [OSTI]

    Damian Ejlli

    2014-11-19

    The oscillation of the CMB photons into axions can cause CMB spectral distortion in the presence of large scale magnetic field. With the COBE limit on the $\\mu$ parameter and a homogeneous magnetic field with strength $B\\lesssim 3.2$ nG at the horizon scale, stronger lower limit on the axion mass in comparison with the limit of the ADMX experiment is found to be, $4.8\\times 10^{-5}$ eV $\\lesssim m_a$ for the KSVZ axion model. On the other hand, using the experimental limit on the axion mass $3.5\\times 10^{-6}$ eV $\\lesssim m_a$ from the ADMX experiment together with the COBE bound on $\\mu$, is found $B\\lesssim 53$ nG for the KSVZ axion model and $B\\lesssim 141$ nG for DFSZ axion model, for a homogeneous magnetic field with coherence length at the present epoch $\\lambda_B\\sim 1.3$ Mpc. Limits on $B$ and $m_a$ for PIXIE/PRISM expected sensitivity on $\\mu$ are derived. If CMB $\\mu$ distortion would be detected by the future space missions PIXIE/PRISM and assuming that the strength of the large scale magnetic field is close to its canonical value, $B\\sim 1-3$ nG, axions in the mass range $2\\, \\mu$eV - $3\\, \\mu$eV would be potential candidates of CMB $\\mu$-distortion.

  4. SLAC All Access: Vacuum Microwave Device Department

    ScienceCinema (OSTI)

    Haase, Andy

    2014-06-13

    The Vacuum Microwave Device Department (VMDD) builds the devices that make SLAC's particle accelerators go. These devices, called klystrons, generate intense waves of microwave energy that rocket subatomic particles up to nearly the speed of light.

  5. Numerical and experimental modelling of microwave applicators

    E-Print Network [OSTI]

    Dibben, David

    1995-10-24

    This thesis presents a time domain finite element method for the solution of microwave heating problems. This is the first time that this particular technique has been applied to microwave heating. It is found that the standard frequency domain...

  6. The Fate of the Universe How one set of equations changed

    E-Print Network [OSTI]

    Olszewski Jr., Edward A.

    10-18 s-1 · H0 -1 14 Gyr #12;Cosmic Microwave Background Radiation (CMB) · Radiation from the "Big distribution suggesting an isotropic and homogeneous universe · The mean temperature is 2.725 ± 0002 K http://map

  7. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    C. L. ; De Putter, R. ; Zahn, O. ; Hou, Z., E-mail: cr@bolo.berkeley.edu We present new limits on early dark energy (EDE) from the cosmic microwave background (CMB) using data...

  8. Ignition methods and apparatus using microwave energy

    DOE Patents [OSTI]

    DeFreitas, Dennis Michael (Oxford, NY); Migliori, Albert (Santa Fe, NM)

    1997-01-01

    An ignition apparatus for a combustor includes a microwave energy source that emits microwave energy into the combustor at a frequency within a resonant response of the combustor, the combustor functioning as a resonant cavity for the microwave energy so that a plasma is produced that ignites a combustible mixture therein. The plasma preferably is a non-contact plasma produced in free space within the resonant cavity spaced away from with the cavity wall structure and spaced from the microwave emitter.

  9. Broadband patterned magnetic microwave absorber

    SciTech Connect (OSTI)

    Li, Wei; Wu, Tianlong; Wang, Wei; Guan, Jianguo, E-mail: guanjg@whut.edu.cn [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Zhai, Pengcheng [School of Science, Wuhan University of Technology, Wuhan 430070 (China)

    2014-07-28

    It is a tough task to greatly improve the working bandwidth for the traditional flat microwave absorbers because of the restriction of available material parameters. In this work, a simple patterning method is proposed to drastically broaden the absorption bandwidth of a conventional magnetic absorber. As a demonstration, an ultra-broadband microwave absorber with more than 90% absorption in the frequency range of 4–40 GHz is designed and experimentally realized, which has a thin thickness of 3.7?mm and a light weight equivalent to a 2-mm-thick flat absorber. In such a patterned absorber, the broadband strong absorption is mainly originated from the simultaneous incorporation of multiple ?/4 resonances and edge diffraction effects. This work provides a facile route to greatly extend the microwave absorption bandwidth for the currently available absorbing materials.

  10. Microwavable thermal energy storage material

    DOE Patents [OSTI]

    Salyer, I.O.

    1998-09-08

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.

  11. Microwavable thermal energy storage material

    DOE Patents [OSTI]

    Salyer, Ival O. (Dayton, OH)

    1998-09-08

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene-vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments.

  12. CMB aberration and Doppler effects as a source of hemispherical asymmetries

    SciTech Connect (OSTI)

    Notari, Alessio [Departament de Física Fondamental i Institut de Ciéncies del Cosmos, Universitat de Barcelona, Martí i Franqués 1, Barcelona, E-08028 (Spain); Quartin, Miguel [Instituto de Física, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos 149, Rio de Janeiro, 21941-972 (Brazil); Catena, Riccardo, E-mail: notari@ffn.ub.es, E-mail: mquartin@if.ufrj.br, E-mail: riccardo.catena@theorie.physik.uni-goettingen.de [Institut für Theoretische Physik, Friedrich-Hund-Platz 1, Göttingen, 37077 (Germany)

    2014-03-01

    Our peculiar motion with respect to the CMB rest frame represents a preferred direction in the observed CMB sky since it induces an apparent deflection of the observed CMB photons (aberration) and a shift in their frequency (Doppler). Both effects distort the multipoles a{sub ?m}'s at all ?'s. Such effects are real as it has been recently measured for the first time by Planck according to what was forecast in some recent papers. However, the common lore when estimating a power spectrum from CMB is to consider that Doppler affects only the ? = 1 multipole, neglecting any other corrections. In this work we use simulations of the CMB sky in a boosted frame with a peculiar velocity ??v/c = 1.23 × 10{sup ?3} in order to assess the impact of such effect on power spectrum estimations in different regions of the sky. We show that the boost induces a north-south asymmetry in the power spectrum which is highly significant and non-negligible, of about (0.58±0.10)% for half-sky cuts when going up to ? ? 2500. We suggest that these effects are relevant and may account for some of the north-south asymmetries seen in the Planck data, being especially important at small scales. Finally we analyze the particular case of the ACT experiment, which observed only a small fraction of the sky and show that it suffers a bias of about 1% on the power spectrum and of similar size on some cosmological parameters: for example the position of the peaks shifts by 0.5% and the overall amplitude of the spectrum is about 0.4% lower than a full-sky case.

  13. Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations

    SciTech Connect (OSTI)

    Gómez-Cadenas, J.J.; Martín-Albo, J.; Vidal, J. Muñoz; Peña-Garay, C., E-mail: gomez@mail.cern.ch, E-mail: jmalbos@ific.uv.es, E-mail: jmunoz@ific.uv.es, E-mail: penya@ific.uv.es [Instituto de Física Corpuscular (IFIC), CSIC and Universitat de Valencia Calle Catedrático José Beltrán, 2, 46090 Paterna, Valencia (Spain)

    2013-03-01

    The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, with ?m{sub ?} = (0.32±0.11) eV. This result, if confirmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass m{sub ??} involved in neutrinoless double beta decay (??0?) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based ??0? experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg·year, could already have a sizeable opportunity to observe ??0? events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton·year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely.

  14. MURI High Energy Microwave Sources F496209510253

    E-Print Network [OSTI]

    Wurtele, Jonathan

    MURI ­ High Energy Microwave Sources F49620­95­1­0253 1 August 1999 to 14 March 2000 PROGRESS University Research Initiative (MURI) High Energy Microwave (HEM) research program. The PTSG, reports, and conference papers. The PTSG is primarily involved in the modeling of microwave­beam, plasma

  15. Microwave heat treating of manufactured components

    DOE Patents [OSTI]

    Ripley, Edward B.

    2007-01-09

    An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

  16. Passive Microwave Systems (Rees Chapter 7)

    E-Print Network [OSTI]

    Sandwell, David T.

    Passive Microwave Systems (Rees Chapter 7) At wavelengths greater than about 2 cm and less than 10 radiation from the Earth dominates". Microwaves penetrate clouds and since the signal is from thermal emissions, passive microwave measurements can be made in all weather and in daytime or nighttime

  17. SIGNATURES OF CORONAL CURRENTS IN MICROWAVE IMAGES

    E-Print Network [OSTI]

    White, Stephen

    : August 12, 1996) Abstract. Microwave emission from solar active regions at frequencies above 4 GHz recognized that microwave emission from solar active regions offers a unique diagnostic of coronal magneticSIGNATURES OF CORONAL CURRENTS IN MICROWAVE IMAGES JEONGWOO LEE, STEPHEN M. WHITE, N. GOPALSWAMY

  18. Microwave assisted centrifuge and related methods

    DOE Patents [OSTI]

    Meikrantz, David H. (Idaho Falls, ID) [Idaho Falls, ID

    2010-08-17

    Centrifuge samples may be exposed to microwave energy to heat the samples during centrifugation and to promote separation of the different components or constituents of the samples using a centrifuge device configured for generating microwave energy and directing the microwave energy at a sample located in the centrifuge.

  19. Satellite remote sensing of global rainfall using passive microwave radiometry

    SciTech Connect (OSTI)

    Ferriday, J.G.

    1994-12-31

    Global rainfall over land and ocean is estimated using measurements of upwelling microwaves by a satellite passive microwave radiometer. Radiative transfer calculations through a cloud model are used to parameterize an inversion technique for retrieving rain rates from brightness temperatures measured by the Special Sensor Microwave Imager (SSM/I). The rainfall retrieval technique is based on the interaction between multi-spectral microwave radiances and millimeter sized liquid and frozen hydrometeors distributed in the satellite`s field of view. The rain rate algorithm is sensitive to both hydrometeor emission and scattering while being relatively insensitive to extraneous atmospheric and surface effects. Separate formulations are used over ocean and land to account for different background microwave characteristics and the algorithm corrects for inhomogeneous distributions of rain rates within the satellite`s field of view. Estimates of instantaneous and climate scale rainfall are validated through comparisons with modeled clouds, surface radars, rain gauges and alternative satellite estimates. The accuracy of the rainfall estimates is determined from a combination of validation comparisons, theoretical sampling error calculations, and modeled sensitivity to variations in atmospheric and surface radiative properties. An error budget is constructed for both instantaneous rain rates and climate scale global estimates. At a one degree resolution, the root mean square errors in instantaneous rain rate estimates are 13% over ocean and 20% over land. The root mean square errors in global rainfall totals over a four month period are found to be 46% over ocean and 63% over land. Global rainfall totals are computed on a monthly scale for a three year period from 1987 to 1990. The time series is analyzed for climate scale rainfall distribution and variability.

  20. Friedel Oscillations in Microwave Billiards

    E-Print Network [OSTI]

    A. Baecker; B. Dietz; T. Friedrich; M. Miski-Oglu; A. Richter; F. Schaefer; S. Tomsovic

    2009-11-23

    Friedel oscillations of electron densities near step edges have an analog in microwave billiards. A random plane wave model, normally only appropriate for the eigenfunctions of a purely chaotic system, can be applied and is tested for non-purely-chaotic dynamical systems with measurements on pseudo-integrable and mixed dynamics geometries. It is found that the oscillations in the pseudo-integrable microwave cavity matches the random plane-wave modeling. Separating the chaotic from the regular states for the mixed system requires incorporating an appropriate phase space projection into the modeling in multiple ways for good agreement with experiment.

  1. Power spectrum sensitivity of raster-scanned CMB experiments in the presence of 1/f noise

    E-Print Network [OSTI]

    Tom Crawford

    2007-09-24

    We investigate the effects of 1/f noise on the ability of a particular class of Cosmic Microwave Background experiments to measure the angular power spectrum of temperature anisotropy. We concentrate on experiments that operate primarily in raster-scan mode and develop formalism that allows us to calculate analytically the effect of 1/f noise on power spectrum sensitivity for this class of experiments and determine the benefits of raster-scanning at different angles relative to the sky field versus scanning at only a single angle (cross-linking versus not cross-linking). We find that the sensitivity of such experiments in the presence of 1/f noise is not significantly degraded at moderate spatial scales (l ~ 100) for reasonable values of scan speed and 1/f knee. We further find that the difference between cross-linked and non-cross-linked experiments is small in all cases and that the non-cross-linked experiments are preferred from a raw sensitivity standpoint in the noise-dominated regime -- i.e., in experiments in which the instrument noise is greater than the sample variance of the target power spectrum at the scales of interest. This analysis does not take into account systematic effects.

  2. Scanning tip microwave near field microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Alameda, CA); Schultz, Peter G. (Oakland, CA); Wei, Tao (Albany, CA)

    1998-01-01

    A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an endwall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity.

  3. Microwave scattering from laser spark in air

    SciTech Connect (OSTI)

    Sawyer, Jordan; Zhang Zhili [Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Shneider, Mikhail N. [Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

    2012-09-15

    In this paper, microwave Mie scattering from a laser-induced plasma in atmospheric air is computed. It shows that the scattered microwave transitions from coherent Rayleigh scattering to Mie scattering based on the relative transparency of the laser-induced plasma at the microwave frequency. The microwave penetration in the plasma alters from total transparency to partial shielding due to the sharp increase of the electron number density within the avalanche ionization phase. The transition from Rayleigh scattering to Mie scattering is verified by both the temporal evolution of the scattered microwave and the homogeneity of polar scattering plots.

  4. Modeling microwave/electron-cloud interaction

    E-Print Network [OSTI]

    Mattes, M; Zimmermann, F

    2013-01-01

    Starting from the separate codes BI-RME and ECLOUD or PyECLOUD, we are developing a novel joint simulation tool, which models the combined effect of a charged particle beam and of microwaves on an electron cloud. Possible applications include the degradation of microwave transmission in tele-communication satellites by electron clouds; the microwave-transmission tecchniques being used in particle accelerators for the purpose of electroncloud diagnostics; the microwave emission by the electron cloud itself in the presence of a magnetic field; and the possible suppression of electron-cloud formation in an accelerator by injecting microwaves of suitable amplitude and frequency. A few early simulation results are presented.

  5. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  6. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  7. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  8. Microwave sintering of boron carbide

    DOE Patents [OSTI]

    Blake, R.D.; Katz, J.D.; Petrovic, J.J.; Sheinberg, H.

    1988-06-10

    A method for forming boron carbide into a particular shape and densifying the green boron carbide shape. Boron carbide in powder form is pressed into a green shape and then sintered, using a microwave oven, to obtain a dense boron carbide body. Densities of greater than 95% of theoretical density have been obtained. 1 tab.

  9. MMS 2007 Mediterranean Microwave Symposium

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and the radiating slots. The design was based on electromagnetic simulations made using the CST Microwave Studio substrate metallization has been used to improve radiation properties. The simulated radiation efficiency is one of the possible solutions for the development of radiofrequency (RF) systems [1], for example

  10. Controlled zone microwave plasma system

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxville, TN)

    2009-10-20

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  11. The Microwave Theory And Application

    E-Print Network [OSTI]

    Masoudi, Husain M.

    was testing a new vacuum tube called a magnetron when he discovered that the candy bar in his pocket had microwave energy. Thus, if an egg can be cooked that quickly , why not other foods? Experimentation began are popular because they cook food in an amazingly short amou nt of time. They are also extremely efficient

  12. Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources

    E-Print Network [OSTI]

    Giommi, P; Cavazzuti, E; Colafrancesco, S; Cucchiara, A; Falcone, A; Kennea, J; Nesci, R; Perri, M; Tagliaferri, G; Tramacere, A; Tosti, G; Blustin, A J; Branduardi-Raymont, G; Burrows, D N; Chincarini, G; Dean, A J; Gehrels, N; Krimm, H; Marshall, F; Parsons, A M; Zhang, B

    2007-01-01

    Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year) were never reported before as X-ray sources. We present here the results of 41 Swift observations which led to the detection of all these 23 blazars in the 0.3-10 keV band. We conclude that all micro-wave selected blazars are X-ray emitters and that the distribution of the micro-wave to X-ray spectral slope $\\alpha_{mu x}$ of LBL blazars is very narrow, confirming that the X-ray flux of most blazars is a very good estimator of their micro-wave emission. The X-ray spectral shape of all the objects that were observed long enough to allow spectral analysis is flat and consistent with inverse Compton emission within the commonly accepted view where the radiation from blazars is emitted in a Sychrotron-Inverse-Compton scenario. We predict that all blazars and most radio galaxies a...

  13. PEAR: Pyrus communis L. 'Bartlett' A. Agnello & D. Kain Comstock mealybug (CMB); Pseudococcis comstocki (Kuwana) Dept. of Entomology

    E-Print Network [OSTI]

    Agnello, Arthur M.

    -tree plots that were replicated 4 times. Treatments were applied using a hand-held gun from a truck). CMB infestation pressure was relatively light in this trial, probably as a direct result of the cool

  14. Foreground contamination of the WMAP CMB maps from the perspective of the matched circle test

    E-Print Network [OSTI]

    H. Then

    2006-10-16

    WMAP has provided CMB maps of the full sky. The raw data is subject to foreground contamination, in particular near to the Galactic plane. Foreground cleaned maps have been derived, e.g., the internal linear combination (ILC) map of Bennett et al. and the reduced foreground TOH map of Tegmark et al. Using S statistics we examine whether residual foreground contamination is left over in the foreground cleaned maps. In particular, we specify which parts of the foreground cleaned maps are sufficiently accurate for the circle-in-the-sky signature. We generalise the S statistic, called D statistic, such that the circle test can deal with CMB maps in which the contaminated regions of the sky are excluded with masks.

  15. Big Bang Nucleosynthesis, Implications of Recent CMB Data and Supersymmetric Dark Matter

    E-Print Network [OSTI]

    Keith A. Olive

    2002-03-01

    The BBN predictions for the abundances of the light element isotopes is reviewed and compared with recent observational data. The single unknown parameter of standard BBN is the baryon-to-photon ratio, \\eta, and can be determined by the concordance between theory and observation. Recent CMB anisotropy measurements also lead to a determination of \\eta and these results are contrasted with those from BBN. In addition, the CMB data indicate that the Universe is spatially flat. Thus it is clear that some form of non-baryonic dark matter or dark energy is necessary. Here I will also review the current expectations for cold dark matter from minimal supersymmetric models. The viability of detecting supersymmetric dark matter will also be discussed.

  16. Planck CMB anomalies: astrophysical and cosmological secondary effects and the curse of masking

    SciTech Connect (OSTI)

    Rassat, A.; Starck, J.-L.; Paykari, P.; Sureau, F.; Bobin, J. E-mail: jstarck@cea.fr E-mail: florent.sureau@cea.fr

    2014-08-01

    Large-scale anomalies have been reported in CMB data with both WMAP and Planck data. These could be due to foreground residuals and or systematic effects, though their confirmation with Planck data suggests they are not due to a problem in the WMAP or Planck pipelines. If these anomalies are in fact primordial, then understanding their origin is fundamental to either validate the standard model of cosmology or to explore new physics. We investigate three other possible issues: 1) the trade-off between minimising systematics due to foreground contamination (with a conservative mask) and minimising systematics due to masking, 2) astrophysical secondary effects (the kinetic Doppler quadrupole and kinetic Sunyaev-Zel'dovich effect), and 3) secondary cosmological signals (the integrated Sachs-Wolfe effect). We address the masking issue by considering new procedures that use both WMAP and Planck to produce higher quality full-sky maps using the sparsity methodology (LGMCA maps). We show the impact of masking is dominant over that of residual foregrounds, and the LGMCA full-sky maps can be used without further processing to study anomalies. We consider four official Planck PR1 and two LGMCA CMB maps. Analysis of the observed CMB maps shows that only the low quadrupole and quadrupole-octopole alignment seem significant, but that the planar octopole, Axis of Evil, mirror parity and cold spot are not significant in nearly all maps considered. After subtraction of astrophysical and cosmological secondary effects, only the low quadrupole may still be considered anomalous, meaning the significance of only one anomaly is affected by secondary effect subtraction out of six anomalies considered. In the spirit of reproducible research all reconstructed maps and codes will be made available for download here http://www.cosmostat.org/anomaliesCMB.html.

  17. Is the CMB shift parameter connected with the growth of cosmological perturbations?

    E-Print Network [OSTI]

    S. Basilakos; S. Nesseris; L. Perivolaropoulos

    2008-04-10

    We verify numerically that in the context of general relativity (GR), flat models which have the same $\\Omega_{\\rm m}$ and CMB shift parameter $R$ but different $H(a)$ and $w(a)$ also have very similar (within less than 8%) growth of perturbations even though the dark energy density evolution is quite different. This provides a direct connection between geometrical and dynamical tests of dark energy and may be used as a cosmological test of general relativity.

  18. Extended analysis of CMB constraints on non-gaussianity in isocurvature perturbations

    SciTech Connect (OSTI)

    Hikage, Chiaki [Kobayashi-Maskawa Institute, Nagoya University, Nagoya 464-8602 (Japan); Kawasaki, Masahiro [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Sekiguchi, Toyokazu [Department of Physics and Astrophysics, Nagoya University, Nagoya 464-8602 (Japan); Takahashi, Tomo, E-mail: hikage@kmi.nagoya-u.ac.jp, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: toyokazu.sekiguchi@nagoya-u.jp, E-mail: tomot@cc.saga-u.ac.jp [Department of Physics, Saga University, Saga 840-8502 (Japan)

    2013-03-01

    We study CMB constraints on non-Gaussianity from isocurvature perturbations of general types. Specifically, we study CDM/neutrino isocurvature perturbations which are uncorrelated or totally correlated with adiabatic ones. Using the data from the WMAP 7-year observation at V and W bands, we obtained optimal constraints on the nonlinearity parameters of adiabatic and isocurvature perturbations. Our result shows that primordial perturbations are consistent with Gaussian ones at around 2? level for above mentioned isocurvature modes.

  19. Dark matter annihilation and its effect on CMB and Hydrogen 21 cm observations

    E-Print Network [OSTI]

    Natarajan, Aravind

    2009-01-01

    If dark matter is made up of Weakly Interacting Massive Particles, the annihilation of these particles in halos results in energy being released, some of which is absorbed by gas, causing partial ionization and heating. It is shown that early ionization results in a transfer of power to higher multipoles in the large angle CMB polarization power spectra. Future CMB experiments may be able to detect this effect in the case of certain light dark matter models. We also investigate the effect of gas heating on the expected H21 cm power spectrum. Heating by particle annihilation results in a decrease in the amplitude of the H21 cm power spectrum as the gas temperature $T$ becomes comparable to the CMB temperature $T_\\gamma$, and then an increase as $T > T_\\gamma$. The result is a minimum in the power spectrum at the redshift for which $T \\approx T_\\gamma$. Only certain models (low particle masses $\\sim$ 10 GeV, or favorable halo parameters) show this effect. Within these models, observations of the H21 cm power sp...

  20. Cosmological parameters from CMB and other data: a Monte-Carlo approach

    E-Print Network [OSTI]

    Antony Lewis; Sarah Bridle

    2002-10-14

    We present a fast Markov Chain Monte-Carlo exploration of cosmological parameter space. We perform a joint analysis of results from recent CMB experiments and provide parameter constraints, including sigma_8, from the CMB independent of other data. We next combine data from the CMB, HST Key Project, 2dF galaxy redshift survey, supernovae Ia and big-bang nucleosynthesis. The Monte Carlo method allows the rapid investigation of a large number of parameters, and we present results from 6 and 9 parameter analyses of flat models, and an 11 parameter analysis of non-flat models. Our results include constraints on the neutrino mass (m_nu < 0.3eV), equation of state of the dark energy, and the tensor amplitude, as well as demonstrating the effect of additional parameters on the base parameter constraints. In a series of appendices we describe the many uses of importance sampling, including computing results from new data and accuracy correction of results generated from an approximate method. We also discuss the different ways of converting parameter samples to parameter constraints, the effect of the prior, assess the goodness of fit and consistency, and describe the use of analytic marginalization over normalization parameters.

  1. Microwave assisted hard rock cutting

    DOE Patents [OSTI]

    Lindroth, David P. (Apple Valley, MN); Morrell, Roger J. (Bloomington, MN); Blair, James R. (Inver Grove Heights, MN)

    1991-01-01

    An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

  2. Microwave solidification development for Rocky Flats waste

    SciTech Connect (OSTI)

    Dixon, D.; Erle, R.; Eschen, V.

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology.

  3. MAR Background Report MAR Background Report: Indigenous Protest in Brazil

    E-Print Network [OSTI]

    Milchberg, Howard

    MAR Background Report MAR Background Report: Indigenous Protest in Brazil Hundreds of indigenous people demonstrated at the National Congress in Brasilia, capital of Brazil, following the announcement in the 1990s in the midst of extensive protests in Brazil and around the world. On February 8, an indigenous

  4. MICROWAVE IMAGING REFLECTOMETRY FOR THE VISUALIZATION OF TURBULENCE IN TOKAMAKS

    E-Print Network [OSTI]

    1 MICROWAVE IMAGING REFLECTOMETRY FOR THE VISUALIZATION OF TURBULENCE IN TOKAMAKS E. Mazzucato of density fluctuations in tokamaks. The proposed method is based on microwave reflectometry and consists are discussed. Key words: Tokamak, anomalous transport, turbulent fluctuations, microwave imaging reflectometry

  5. Global longterm passive microwave satellitebased retrievals of vegetation optical depth

    E-Print Network [OSTI]

    Evans, Jason

    Global longterm passive microwave satellitebased retrievals of vegetation optical depth Yi Y. Liu,1 optical depth (VOD) retrievals from three satellitebased passive microwave instruments were merged longterm passive microwave satellitebased retrievals of vegetation optical depth, Geophys. Res. Lett., 38

  6. MICROWAVE RADIOMETER INTER-CALIBRATION: ALGORITHM DEVELOPMENT AND APPLICATION

    E-Print Network [OSTI]

    Ruf, Christopher

    MICROWAVE RADIOMETER INTER-CALIBRATION: ALGORITHM DEVELOPMENT AND APPLICATION by Rachael Ann 1.2.2 Microwave Remote Sensing............................................................................... 8 1.2.4 Spaceborne Microwave Radiometers: Roadmap to TRMM and GPM ...... 10 1.2.5 The Tropical

  7. An Efficient Microwave Power Source: Free-electron Laser Afterburner

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01

    Proceedings of Intense Microwave Pulses (SPIE, Los Angeles,Physics An Efficient Microwave Power Source: Free-Electron4 UC-414 An Efficient Microwave Power Source: Free-electron

  8. Measurement of electron clouds in large accelerators by microwave dispersion

    E-Print Network [OSTI]

    De Santis, Stefano

    2008-01-01

    in Large Accelerators by Microwave Dispersion S. De Santis,li.e. , phase shift) of a microwave signal propagating in thethe phase shift of the microwave signal through the electron

  9. Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast

    E-Print Network [OSTI]

    Wang, Lihong

    Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast Geng Ku Scanning thermoacoustic tomography was explored in the microwave region of the electromagnetic spectrum ultrasonic transducer detected the time-resolved thermoacoustic signals. Based on the microwave

  10. Microwave Photon Counter Based on Josephson Junctions

    E-Print Network [OSTI]

    Y. -F. Chen; D. Hover; S. Sendelbach; L. Maurer; S. T. Merkel; E. J. Pritchett; F. K. Wilhelm; R. McDermott

    2011-11-07

    We describe a microwave photon counter based on the current-biased Josephson junction. The junction is tuned to absorb single microwave photons from the incident field, after which it tunnels into a classically observable voltage state. Using two such detectors, we have performed a microwave version of the Hanbury Brown and Twiss experiment at 4 GHz and demonstrated a clear signature of photon bunching for a thermal source. The design is readily scalable to tens of parallelized junctions, a configuration that would allow number-resolved counting of microwave photons.

  11. Process for microwave sintering boron carbide

    DOE Patents [OSTI]

    Holcombe, C.E.; Morrow, M.S.

    1993-10-12

    A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

  12. Process for microwave sintering boron carbide

    DOE Patents [OSTI]

    Holcombe, Cressie E. (440 Sugarwood Dr., Knoxville, TN 37922); Morrow, Marvin S. (Rte. #3, Box 113, Kingston, TN 37763)

    1993-01-01

    A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

  13. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3259 Investigation of Photonically Assisted Microwave

    E-Print Network [OSTI]

    Yao, Jianping

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3259 Investigation of Photonically Assisted Microwave Frequency Multiplication Based on External Modulation Wangzhe Li, Student Member, IEEE, and Jianping Yao, Senior Member, IEEE Abstract--Microwave frequency

  14. Background reduction in cryogenic detectors

    SciTech Connect (OSTI)

    Bauer, Daniel A.; /Fermilab

    2005-04-01

    This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.

  15. Linear theory of microwave instability in electron storage rings...

    Office of Scientific and Technical Information (OSTI)

    Linear theory of microwave instability in electron storage rings Citation Details In-Document Search Title: Linear theory of microwave instability in electron storage rings...

  16. Microwave (MW) and Radio Frequency (RF) as Enabling Technologies...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced Manufacturing Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced...

  17. Energy Efficiency Standards for Microwave Ovens Saves Consumers...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Efficiency Standards for Microwave Ovens Saves Consumers Energy and Updates the Social Cost of Carbon Energy Efficiency Standards for Microwave Ovens Saves Consumers Energy...

  18. Microwave (MW) and Radio Frequency (RF) as Enabling Technologies...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    International Microwave Power Institute (IMPI), the Japan Society of Electromagnetic Wave Energy Application (JEMEA) and microwave groups from China, India, Russia and Australia....

  19. Background

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    172,000 sq. ft. of space with its two current divisions, EMCORE Fiber Optics and EMCORE Solar Photovoltaics. In October 2006, EMCORE moved its corporate headquarters to...

  20. Background

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from selling an equivalent amount of surplus power. ..... 4 e. Calculation of the net financial value of tangible economic benefits of selling power to Alcoa which would not...

  1. Background

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    not need to have "perfect information before it takes any action." N. Carolina v. Fed. Energy Regulatory Comm'n, 112 F.3d 1175, 1190 (D.C. Cir. 1997) (quoting Dep't of the Interior...

  2. Background:

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    iSUPPLIER PORTAL ACCESS SYSTEM REQUIREMENTS Oracle PO Team mlbritt Page 1 10282010 TABLE OF CONTENTS Recommended Browsers for iSupplier Portal Recommended Microsoft Internet...

  3. Background

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    loads, the Old Corrugated Container (OCC) load (3.275 aMW) and the Unbleached Kraft Pulp and Paper (main mill) load (approximately 17 aMW). PTPC's Contract Demand, defined in...

  4. Background

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    to ADMINISTRATOR'S DRAFT EQUIVALENT BENEFITS ANALYSIS DETERMINATION FOR CONTRACT OFFER TO THE PORT TOWNSEND PAPER CORPORATION February 3, 2011 This page intentionally left...

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass andAtomsVehicles and Fuelsj B JBACKGROUND The safe

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O OLaura BeaneCardwell, ScottGreat:10,-2014 SignJR DTih

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    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and700, 1. .&. 'explains the potential health

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby a contractor ofvarDOE PAGES11NationalEnergy Star

  19. Method of sintering materials with microwave radiation

    DOE Patents [OSTI]

    Kimrey, Jr., Harold D. (Knoxville, TN); Holcombe, Jr., Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN)

    1994-01-01

    A method of sintering ceramic materials following: A compacted article comprising inorganic particles coated with carbon is provided, the carbon providing improved microwave coupling. The compacted article is then heated by microwave radiation to a temperature and for a period of time sufficient to sinter the compacted article.

  20. Microwave-enhanced chemical processes

    DOE Patents [OSTI]

    Varma, R.

    1990-06-19

    A process is disclosed for the disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400 C in the presence of microwave radiation for a time sufficient breaks the hydrocarbon chlorine bonds. Detoxification values in excess of 80 are provided and further detoxification of the bed is followed by additional disposal of toxic wastes. 1 figure.

  1. Microwave drying of ferric oxide pellets

    SciTech Connect (OSTI)

    Pickles, C.A.; Xia, D.K. [Queens` Univ., Kingston, Ontario (Canada). Dept. of Materials and Metallurgical Engineering

    1997-12-31

    The application of microwave energy for the drying of ferric oxide pellets has been investigated and evaluated. It is shown that the microwave drying rates are much higher than those observed in the conventional process. Also there is some potential for improved quality of the product. As a stand-alone technology it is unlikely that microwave drying would be economical for pellets due to the low cost of conventional fuels. However, based on an understanding of the drying mechanisms in the conventional process and in the microwave process, it is shown that microwave-assisted drying offers considerable potential. In this hybrid process, the advantages of the two drying techniques are combined to provide an improved drying process.

  2. Tandem microwave waste remediation and decontamination system

    DOE Patents [OSTI]

    Wicks, George G. (North Aiken, SC); Clark, David E. (Gainesville, FL); Schulz, Rebecca L. (Gainesville, FL)

    1999-01-01

    The invention discloses a tandem microwave system consisting of a primary chamber in which microwave energy is used for the controlled combustion of materials. A second chamber is used to further treat the off-gases from the primary chamber by passage through a susceptor matrix subjected to additional microwave energy. The direct microwave radiation and elevated temperatures provide for significant reductions in the qualitative and quantitative emissions of the treated off gases. The tandem microwave system can be utilized for disinfecting wastes, sterilizing materials, and/or modifying the form of wastes to solidify organic or inorganic materials. The simple design allows on-site treatment of waste by small volume waste generators.

  3. Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole

    E-Print Network [OSTI]

    Takahashi, Yuki David

    2010-01-01

    scans (50 min) Elevation nod (1 min) => Azimuth (deg) Figurescans, a ±0.6 ? elevation “nod” was performed to measuresight airmass (“ elevation nods”), described in §4.2.2. An

  4. Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    Myers, Michael James

    2010-01-01

    This can be done using the Noise Equivalent Power (NEP).The NEP is defined as the optical power required at theconveniently produces a constant NEP for a Gaussian white

  5. A Log-Periodic Focal-Plane Architecture for Cosmic Microwave Background Polarimetry

    E-Print Network [OSTI]

    OBrient, Roger

    2010-01-01

    1.1 2.1 2.2 2.3 2.4 2.5 2.6 NEP of Bolometeric detectors vspublication date. NEP is de?ned as the source power that aPublishers, 1996. Halverson, N. , NEP and Mapping speed for

  6. Design and Deployment of the POLARBEAR Cosmic Microwave Background Polarization Experiment

    E-Print Network [OSTI]

    Arnold, Kam Stahly

    2010-01-01

    bolometer . . . . . . . . . . . . . . . . . . . . NEP g as at in the Layers of the T c and NEP g polarbear focal planethe Noise Equivalent Power (NEP), with units of W / Hz, is

  7. Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope

    E-Print Network [OSTI]

    Lueker, Martin Van

    2010-01-01

    and NEP . . . . . . . . . . . . . . . . . . . . . . Ctemperatures. The value of NEP comes from the photon noisein power on the sensor the NEP is simply equal to the square

  8. The POLARBEAR Cosmic Microwave Background Polarization Experiment and Anti-Reflection Coatings for Millimeter Wave Observations

    E-Print Network [OSTI]

    Quealy, Erin

    2012-01-01

    Flat Anti-Reflection Coating . . . . . . . . . . 4.3.2 Anti-Kam Arnold . . . . . . . . . . . . . . . . AR CoatingAnti-Reflection Coatings . . . . . 2.2.2 Signal and Mapping

  9. Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole

    E-Print Network [OSTI]

    Takahashi, Yuki David

    2010-01-01

    Bierman, J. J. Bock, C. D. Dowell, L. Duband, E. F. Hivon,Bock, H. C. Chiang, C. D. Dowell, L. Duband, E. F. Hivon, W.Chiang, A. Crites, C. D. Dowell, L. Duband, G. S. Griffin,

  10. Design and Deployment of the POLARBEAR Cosmic Microwave Background Polarization Experiment

    E-Print Network [OSTI]

    Arnold, Kam Stahly

    2010-01-01

    Brevik, B. Burger, C. D. Dowell, L. Duband, J. P. Filippini,Brevik, B. Burger, C. D. Dowell, L. Duband, J. P. Filippini,Bierman, J. J. Bock, C. D. Dowell, L. Duband, E. F. Hivon,

  11. Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    Myers, Michael James

    2010-01-01

    4.3.2 Superconducting microstrip simulations 4.4 Impedance4.3 Superconducting microstrip . . . . . . . . . . 4.3.1Principles of superconductive devices and circuits, (second

  12. Post-inflationary non-Gaussianities on the cosmic microwave background

    E-Print Network [OSTI]

    Su, Shi Chun

    2015-06-30

    of Stress-Energy Tensor . . . . . . . . . 34 3.1.3 Einstein Field Equations . . . . . . . . . . . . . . . . . . . . . . . 36 3.1.4 Continuity and Euler Equations . . . . . . . . . . . . . . . . . . . 41 3.2 Second-order Boltzmann Equation... .2.4 Perturbed Optical Depth . . . . . . . . . . . . . . . . . . . . . . . 51 3.2.5 Truncation Scheme for the Boltzmann Hierarchy . . . . . . . . . . 55 3.3 Numerical Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3.3.1 Initial Conditions...

  13. Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    Myers, Michael James

    2010-01-01

    ment with Newton’s law of gravitation. Only in cases ofpublished his Law of Universal Gravitation. This theory

  14. The Anisotropy in the Cosmic Microwave Background At Degree Angular Scales.

    E-Print Network [OSTI]

    are 36­39.5, 39.5­43, 43­46 GHz. The six channels in each radiometer view the sky in a single­axis parabola. The FWHM beam in K a band is 1:42 \\Sigma 0:02 ffi and in Q band is 1:04 \\Sigma 0:02 ffi . After

  15. Progress of the Array for Microwave Background Anisotropy Philippe Raffin*a

    E-Print Network [OSTI]

    Koch, Patrick

    fiber fully steerable platform is mounted on the Hexapod Mount. After integration and equipment by Finite Element Analysis. The Hexapod servo control is now operational and equipment of the platformBA, Hexapod operation, Photogrammetry, Pointing 1. INTRODUCTION The Institute of Astronomy and Astrophysics

  16. The POLARBEAR Cosmic Microwave Background Polarization Experiment and Anti-Reflection Coatings for Millimeter Wave Observations

    E-Print Network [OSTI]

    Quealy, Erin

    2012-01-01

    6.7 Molding defects. Misalignment of the hemisphere and moldmold offset Figure 6.7: Molding defects. Misalignment of the

  17. Hierarchical Bayesian Detection Algorithm for Early-Universe Relics in the Cosmic Microwave Background

    E-Print Network [OSTI]

    McEwen, Jason

    London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ, U.K. 5 Department of Mathematics, Imperial College London, London SW7 2AZ, U.K. (Dated: August 20, 2013) A number of theoretically well to establish its validity. The approximation is implemented using a modular algorithm, designed to avoid

  18. Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole

    E-Print Network [OSTI]

    Takahashi, Yuki David

    2010-01-01

    South Pole Dark Sector and LC-130 . . . . . . .2.2 South Pole site . . . . . . . . . . . . . .Bicep Telescope at the South Pole by Yuki David Takahashi A

  19. Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope

    E-Print Network [OSTI]

    Lueker, Martin Van

    2010-01-01

    6 The South Pole Telescope Atmospheric Conditionsat the South Pole Telescope and Optical Design . . . . . . .interplay of cable delays, poles, resonances and zeroes in

  20. A measurement of the cosmic microwave background damping tail from the

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnicalInformation4563 LLNL(Technical Report)Asegment,the determination

  1. Background Investigation Responsible Administrative Unit

    E-Print Network [OSTI]

    safety of the campus community or unacceptable risks to the integrity of financial processes, assets on the Protection of Minors. Specifically, background investigations will be conducted on persons to whom it offers

  2. Pure pseudo-C_l estimators for CMB B-modes

    E-Print Network [OSTI]

    Kendrick M. Smith

    2006-08-30

    Fast heuristically weighted, or pseudo-C_l, estimators are a frequently used method for estimating power spectra in CMB surveys with large numbers of pixels. Recently, Challinor & Chon showed that the E-B mixing in these estimators can become a dominant contaminant at low noise levels, ultimately limiting the gravity wave signal which can be detected on a finite patch of sky. We define a modified version of the estimators which eliminates E-B mixing and is near-optimal at all noise levels.

  3. Low Background Counting at LBNL

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Smith, A. R.; Thomas, K. J.; Norman, E. B.; Chan, Y. D.; Lesko, K. T.; Hurley, D. L.

    2015-03-24

    The Low Background Facility (LBF) at Lawrence Berkeley National Laboratory in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background cave and remotely at an underground location that historically has operated underground in Oroville, CA, but has recently been relocated to the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K)more »or common cosmogenic/anthropogenic products, as well as active screening via Neutron Activation Analysis for specific applications. The LBF also provides hosting services for general R&D testing in low background environments on the surface or underground for background testing of detector systems or similar prototyping. A general overview of the facilities, services, and sensitivities is presented. Recent activities and upgrades will also be presented, such as the completion of a 3? anticoincidence shield at the surface station and environmental monitoring of Fukushima fallout. The LBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.« less

  4. Photonic microwave bandpass filter with improved dynamic range

    E-Print Network [OSTI]

    Yao, Jianping

    Photonic microwave bandpass filter with improved dynamic range Yu Yan and Jianping Yao* Microwave A technique to improve the dynamic range of a photonic microwave bandpass filter is proposed and experi. The dynamic range of the photonic microwave bandpass filter is increased by reducing the optical

  5. Microwaving of normally opaque and semi-opaque substances

    DOE Patents [OSTI]

    Sheinberg, H.; Meek, T.T.; Blake, R.D.

    1990-07-17

    Disclosed is a method of heating small particles using microwave radiation which are not normally capable of being heated by microwaves. The surfaces of the particles are coated with a material which is transparent to microwave radiation in order to cause microwave coupling to the particles and thus accomplish heating of the particles.

  6. The COMPTEL instrumental line background

    E-Print Network [OSTI]

    G. Weidenspointner; M. Varendorff; U. Oberlack; D. Morris; S. Plueschke; R. Diehl; S. C. Kappadath; M. McConnell; J. Ryan; V. Schoenfelder; H. Steinle

    2000-12-14

    The instrumental line background of the Compton telescope COMPTEL onboard the Compton Gamma-Ray Observatory is due to the activation and/or decay of many isotopes. The major components of this background can be attributed to eight individual isotopes, namely 2D, 22Na, 24Na, 28Al, 40K, 52Mn, 57Ni, and 208Tl. The identification of instrumental lines with specific isotopes is based on the line energies as well as on the variation of the event rate with time, cosmic-ray intensity, and deposited radiation dose during passages through the South-Atlantic Anomaly. The characteristic variation of the event rate due to a specific isotope depends on its life-time, orbital parameters such as the altitude of the satellite above Earth, and the solar cycle. A detailed understanding of the background contributions from instrumental lines is crucial at MeV energies for measuring the cosmic diffuse gamma-ray background and for observing gamma-ray line emission in the interstellar medium or from supernovae and their remnants. Procedures to determine the event rate from each background isotope are described, and their average activity in spacecraft materials over the first seven years of the mission is estimated.

  7. Low Background Micromegas in CAST

    E-Print Network [OSTI]

    J. G. Garza; S. Aune; D. Calvet; J. F. Castel; F. E. Christensen; T. Dafni; M. Davenport; T. Decker; E. Ferrer-Ribas; J. Galán; J. A. García; I. Giomataris; R. M. Hill; F. J. Iguaz; I. G. Irastorza; A. C. Jakobsen; D. Jourde; H. Mirallas; I. Ortega; T. Papaevangelou; M. J. Pivovaroff; J. Ruz; A. Tomás; T. Vafeiadis; J. K. Vogel

    2015-03-17

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as the strategies to further reduce the background level. Finally, we will describe the R&D paths to achieve sub-keV energy thresholds, which could broaden the physics case of axion helioscopes.

  8. On the dipole straylight contamination in spinning space missions dedicated to CMB anisotropy

    E-Print Network [OSTI]

    Carlo Burigana; Alessandro Gruppuso; Fabio Finelli

    2006-07-21

    We present an analysis of the dipole straylight contamination (DSC) for spinning space-missions designed to measure CMB anisotropies. Although this work is mainly devoted to the {\\sc Planck} project, it is relatively general and allows to focus on the most relevant DSC implications. We first study a simple analytical model for the DSC in which the pointing direction of the main spillover can be assumed parallel or not to the spacecraft spin axis direction and compute the time ordered data and map. The map is then analysed paying particular attention to the DSC of the low multipole coefficients of the map. Through dedicated numerical simulations we verify the analytical results and extend the analysis to higher multipoles and to more complex (and realistic) cases by relaxing some of the simple assumptions adopted in the analytical approach. We find that the systematic effect averages out in an even number of surveys, except for a contamination of the dipole itself that survives when spin axis and spillover directions are not parallel and for a contamination of the other multipoles in the case of complex scanning strategies. In particular, the observed quadrupole can be affected by the DSC in an odd number of surveys or in the presence of survey uncompleteness or over-completeness. Various aspects relevant in CMB space projects (such as implications for calibration, impact on polarization measurements, accuracy requirement in the far beam knowledge for data analysis applications, scanning strategy dependence) are discussed.

  9. Constraints on the neutrino parameters by future cosmological 21cm line and precise CMB polarization observations

    E-Print Network [OSTI]

    Yoshihiko Oyama; Kazunori Kohri; Masashi Hazumi

    2015-10-13

    Observations of the 21 cm line radiation coming from the epoch of reionization have a great capacity to study the cosmological growth of the Universe. Also, CMB polarization produced by gravitational lensing has a large amount of information about the growth of matter fluctuations at late time. In this paper, we investigate their sensitivities to the impact of neutrino property on the growth of density fluctuations, such as the total neutrino mass, the effective number of neutrino species (extra radiation), and the neutrino mass hierarchy. We will show that by combining a precise CMB polarization observations such as Simons Array with a 21 cm line observation such as Square kilometer Array (SKA) phase 1 and a baryon acoustic oscillation observation (Dark Energy Spectroscopic Instrument:DESI) we can measure effects of non-zero neutrino mass on the growth of density fluctuation if the total neutrino mass is larger than 0.1eV. Additionally, the combinations can strongly improve errors of the bounds on the effective number of neutrino species sigma(N_nu) ~ 0.06-0.09 at 95 % C.L.. Finally, by using SKA phase 2, we can determine the neutrino mass hierarchy at 95 % C.L. if the total neutrino mass is similar to or smaller than 0.1 eV.

  10. Constraints on the neutrino parameters by future cosmological 21cm line and precise CMB polarization observations

    E-Print Network [OSTI]

    Oyama, Yoshihiko; Hazumi, Masashi

    2015-01-01

    Observations of the 21 cm line radiation coming from the epoch of reionization have a great capacity to study the cosmological growth of the Universe. Also, CMB polarization produced by gravitational lensing has a large amount of information about the growth of matter fluctuations at late time. In this paper, we investigate their sensitivities to the impact of neutrino property on the growth of density fluctuations, such as the total neutrino mass, the effective number of neutrino species (extra radiation), and the neutrino mass hierarchy. We will show that by combining a precise CMB polarization observations such as Simons Array with a 21 cm line observation such as Square kilometer Array (SKA) phase 1 and a baryon acoustic oscillation observation (Dark Energy Spectroscopic Instrument:DESI) we can measure effects of non-zero neutrino mass on the growth of density fluctuation if the total neutrino mass is larger than 0.1eV. Additionally, the combinations can strongly improve errors of the bounds on the effect...

  11. A test of the Poincare dodecahedral space topology hypothesis with the WMAP CMB data

    E-Print Network [OSTI]

    B. S. Lew; B. F. Roukema

    2008-04-24

    It has been suggested by Roukema and coworkers (hereafter R04) that the topology of the Universe as probed by the ``matched circles'' method using the first year release of the WMAP CMB data, might be that of the Poincar\\'e dodecahedral space (PDS) model. An excess in the correlation of the ``identified circles'' was reported by R04, for circles of angular radius of ~11 deg for a relative phase twist -36deg, hinting that this could be due to a Clifford translation, if the hypothesized model were true. R04 did not however specify the statistical significance of the correlation signal. We investigate the statistical significance of the signal using Monte Carlo CMB simulations in a simply connected Universe, and present an updated analysis using the three-year WMAP data. We find that our analyses of the first and three year WMAP data provide results that are consistent with the simply connected space at a confidence level as low as 68%.

  12. 496 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 2, FEBRUARY 2009 Chirped Microwave Pulse Compression Using

    E-Print Network [OSTI]

    Yao, Jianping

    496 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 2, FEBRUARY 2009 Chirped Microwave Pulse Compression Using a Photonic Microwave Filter With a Nonlinear Phase Response Chao Wang, Student Member, IEEE, and Jianping Yao, Senior Member, IEEE Abstract--Chirped microwave pulse compression

  13. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 2, FEBRUARY 2009 505 Microwave Frequency Measurement Based on

    E-Print Network [OSTI]

    Yao, Jianping

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 2, FEBRUARY 2009 505 Microwave, Hao Chi, and Jianping Yao, Senior Member, IEEE Abstract--An approach to the measurement of a microwave and investigated. In the proposed system, a microwave signal is applied to a Mach­Zehnder mod- ulator, which

  14. MICROWAVE IMAGING FOR DAMAGE DETECTION Microwave imaging technology has been developed to detect invisible damage such as

    E-Print Network [OSTI]

    De Flaviis, Franco

    MICROWAVE IMAGING FOR DAMAGE DETECTION By ABSTRACT Microwave imaging technology has been developed to construct 2D and 3D objects from the scattered microwave fields. Both numerical simulation and experiments demonstrated the effectiveness of the proposed microwave imaging technology in detecting voids inside

  15. Microwave meta-atom enhanced spintronic rectification

    SciTech Connect (OSTI)

    Gou, Peng; Xi, Fuchun; Qian, Qinbai; Xu, Jie; Gui, Y. S.; Hu, C.-M.; An, Zhenghua

    2015-04-06

    An artificial meta-atom (MA), or alternatively, a plasmonic antenna, has been demonstrated to significantly enhance the microwave spin rectifying photovoltage by more than two orders in magnitude (?280) in the ferromagnetic resonance regime. The large enhancement is attributed to the unique structure of the MA which magnifies both microwave electric (?5) and magnetic (?56) fields in the same near-field spatial region. Our work develops the interdisciplinary direction with artificial and natural magnetism and may find promising applications in high-frequency or opto-spintronic devices and wireless microwave energy harvesting.

  16. Detector Background at Muon Colliders

    SciTech Connect (OSTI)

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2011-09-01

    Physics goals of a Muon Collider (MC) can only be reached with appropriate design of the ring, interaction region (IR), high-field superconducting magnets, machine-detector interface (MDI) and detector. Results of the most recent realistic simulation studies are presented for a 1.5-TeV MC. It is shown that appropriately designed IR and MDI with sophisticated shielding in the detector have a potential to substantially suppress the background rates in the MC detector. The main characteristics of backgrounds are studied.

  17. Microwave Excitation In ECRIS plasmas

    SciTech Connect (OSTI)

    Ciavola, G.; Celona, L.; Consoli, F.; Gammino, S.; Maimone, F.; Barbarino, S.; Catalano, R. S.; Mascali, D.; Tumino, L.

    2007-09-28

    A number of phenomena related to the electron cyclotron resonance ion sources (ECRIS) has been better understood recently by means of the improvement of comprehension of the coupling mechanism between microwave generators and ECR plasma. In particular, the two frequency heating and the frequency tuning effect, that permit a remarkable increase of the current for the highest charge states ions, can be explained in terms of modes excitation in the cylindrical cavity of the plasma chamber. Calculations based on this theoretical approach have been performed, and the major results will be presented. It will be shown that the electric field pattern completely changes for a few MHz frequency variations and the changes in ECRIS performances can be correlated to the efficiency of the power transfer between electromagnetic field and plasma.

  18. Planar slot coupled microwave hybrid

    DOE Patents [OSTI]

    Petter, Jeffrey K. (Williston, VT)

    1991-01-01

    A symmetrical 180.degree. microwave hybrid is constructed by opening a slot line in a ground plane below a conducting strip disposed on a dielectric substrate, creating a slot coupled conductor. Difference signals propagating on the slot coupled conductor are isolated on the slot line leaving sum signals to propagate on the microstrip. The difference signal is coupled from the slot line onto a second microstrip line for transmission to a desired location. The microstrip branches in a symmetrical fashion to provide the input/output ports of the 180.degree. hybrid. The symmetry of the device provides for balance and isolation between sum and difference signals, and provides an advantageous balance between the power handling capabilities and the bandwidth of the device.

  19. SIMULATION AND ANALYSIS OF MICROWAVE TRANSMISSION THROUGH AN ELECTRON CLOUD, A COMPARISON OF RESULTS

    E-Print Network [OSTI]

    Sonnad, Kiran G.; Furman, Miguel; Veitzer, Seth A.; Cary, John

    2008-01-01

    of the propagation of microwaves through electron cloudsSimulation and analysis of microwave transmission through anfor transmission of microwaves through electron cloudes show

  20. Microwave Transmission Measurements of the Electron Cloud density In the Positron Ring of PEP-II

    E-Print Network [OSTI]

    Pivi, Mauro T.F.

    2009-01-01

    frequency is equal to the microwave frequency, the totalMICROWAVE TRANSMISSION MEASUREMENT OF THE ELECTRON CLOUDCERN SPS Experiment On Microwave Transmission Through the

  1. Microwave Ion Source and Beam Injection for an Accelerator-driven Neutron Source

    E-Print Network [OSTI]

    2007-01-01

    LBNL-62514 MICROWAVE ION SOURCE AND BEAM INJECTION FOR ANAbstract An over-dense microwave driven ion source capableregion. Matching of the microwave power from the waveguide

  2. CANCELLED Microwave Ion Source and Beam Injection for an Accelerator-Driven Neut ron Source

    E-Print Network [OSTI]

    2008-01-01

    Abstract An over-dense microwave driven ion source capableregion. Matching of the microwave power from the waveguideperveance. ION SOURCE Microwave source was selected due to

  3. DETECTION AND MEASUREMENTS OF AIR POLLUTANTS AND CONSTITUENTS BY MELLIMETER-WAVE MICROWAVE SPECTROSCOPY

    E-Print Network [OSTI]

    Leskovar, Branko

    2011-01-01

    of Sulfur Dioxide Microwave Rotational Lines. Journal ofT. Buscher, B. Leskovar, Microwave Absorption CoefficientsPiezo- electric-Tuned Microwave Cavity for Absorption

  4. Simulation and Analysis of Microwave Transmission through an Electron Cloud, a Comparison of Results

    E-Print Network [OSTI]

    Sonnad, Kiran

    2008-01-01

    of the propagation of microwaves through electron cloudsSIMULATION AND ANALYSIS OF MICROWAVE TRANSMISSION THROUGH ANfor transmission of microwaves through electron cloudes show

  5. Low Background Micromegas in CAST

    E-Print Network [OSTI]

    Garza, J G; Calvet, D; Castel, J F; Christensen, F E; Dafni, T; Davenport, M; Decker, T; Ferrer-Ribas, E; Galán, J; García, J A; Giomataris, I; Hill, R M; Iguaz, F J; Irastorza, I G; Jakobsen, A C; Jourde, D; Mirallas, H; Ortega, I; Papaevangelou, T; Pivovaroff, M J; Ruz, J; Tomás, A; Vafeiadis, T; Vogel, J K

    2015-01-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as ...

  6. Experimental and theoretical investigations of microwave heating 

    E-Print Network [OSTI]

    Kota, Bhagat Chandra

    2004-09-30

    In this work we proposed the governing equations for describing the microwave heating process where the complex interactions between the thermo-mechanical and electromagnetic fields are taken into account. Starting point are the general balance laws...

  7. Modulated microwave microscopy and probes used therewith

    DOE Patents [OSTI]

    Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

    2012-09-11

    A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

  8. Continuous, real time microwave plasma element sensor

    DOE Patents [OSTI]

    Woskov, P.P.; Smatlak, D.L.; Cohn, D.R.; Wittle, J.K.; Titus, C.H.; Surma, J.E.

    1995-12-26

    Microwave-induced plasma is described for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury. 3 figs.

  9. Continuous, real time microwave plasma element sensor

    DOE Patents [OSTI]

    Woskov, Paul P. (4 Ledgewood Dr., Bedford, MA 01730); Smatlak, Donna L. (10 Village Hill Rd., Belmont, MA 02178); Cohn, Daniel R. (26 Walnut Hill Rd., Chestnut Hill, MA 02167); Wittle, J. Kenneth (1740 Conestoga Rd., Chester Springs, PA 19425); Titus, Charles H. (323 Echo Valley La., Newton Square, PA 19072); Surma, Jeffrey E. (806 Brian La., Kennewick, WA 99337)

    1995-01-01

    Microwave-induced plasma for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury.

  10. Chemical vapor infiltration using microwave energy

    DOE Patents [OSTI]

    Devlin, David J. (Los Alamos, NM); Currier, Robert P. (Los Alamos, NM); Laia, Jr., Joseph R. (Los Alamos, NM); Barbero, Robert S. (Santa Cruz, NM)

    1993-01-01

    A method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

  11. Container evaluation for microwave solidification project

    SciTech Connect (OSTI)

    Smith, J.A.

    1994-08-01

    This document discusses the development and testing of a suitable waste container and packaging arrangement to be used with the Microwave Solidification System (MSS) and Bagless Posting System (BPS). The project involves the Rocky Flats Plant.

  12. Detection of contraband using microwave radiation

    DOE Patents [OSTI]

    Toth, Richard P. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Bacon, Larry D. (Albuquerque, NM); Watson, Robert D. (Tijeras, NM)

    2002-01-01

    The present invention relates to a method and system for using microwave radiation to detect contraband hidden inside of a non-metallic container, such as a pneumatic vehicle tire. The method relies on the attenuation, retardation, time delay, or phase shift of microwave radiation as it passes through the container plus the contraband. The method is non-invasive, non-destructive, low power, and does not require physical contact with the container.

  13. Continuous microwave regeneration apparatus for absorption media

    DOE Patents [OSTI]

    Smith, Douglas D. (Knoxville, TN)

    1999-01-01

    A method and apparatus for continuously drying and regenerating ceramic beads for use in process gas moisture drying operations such as glove boxes. A microwave energy source is coupled to a process chamber to internally heat the ceramic beads and vaporize moisture contained therein. In a preferred embodiment, the moisture laden ceramic beads are conveyed toward the microwave source by a screw mechanism. The regenerated beads flow down outside of the screw mechanism and are available to absorb additional moisture.

  14. Microwaves in Photochemistry and Photocatalysis Vladimir Cirkva

    E-Print Network [OSTI]

    Cirkva, Vladimir

    563 14 Microwaves in Photochemistry and Photocatalysis Vladim´ir C´irkva 14.1 Introduction photocatalysis. The energy of MW radia- tion (e.g., E = 0.98 J mol-1 at = 2.45 GHz) is considerably lower than by Wiley-VCH Verlag GmbH & Co. KGaA. #12;564 14 Microwaves in Photochemistry and Photocatalysis UV

  15. The Microwave Air Yield Beam Experiment (MAYBE): measurement of GHz radiation for Ultra-High Energy Cosmic Rays detection

    E-Print Network [OSTI]

    M. Monasor; M. Bohacova; C. Bonifazi; G. Cataldi; S. Chemerisov; J. R. T. De Mello Neto; P. Facal San Luis; B. Fox; P. W. Gorham; C. Hojvat; N. Hollon; R. Meyhandan; L. C. Reyes; B. Rouille D'Orfeuil; E. M. Santos; J. Pochez; P. Privitera; H. Spinka; V. Verzi; C. Williams; J. Zhou

    2011-08-31

    We present first measurements by MAYBE of microwave emission from an electron beam induced air plasma, performed at the electron Van de Graaff facility of the Argonne National Laboratory. Coherent radio Cherenkov, a major background in a previous beam experiment, is not produced by the 3 MeV beam, which simplifies the interpretation of the data. Radio emission is studied over a wide range of frequencies between 3 and 12 GHz. This measurement provides further insight on microwave emission from extensive air showers as a novel detection technique for Ultra-High Energy Cosmic Rays.

  16. Portsmouth Background | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof EnergyAprilEnergyPartnership forHydrogenandGuidanceBackground

  17. Statistics of solar microwave radio burst spectra with implications for operations of microwave radio systems

    E-Print Network [OSTI]

    .6 GHz to employ an adaptable mode wherein, if the prediction of solar activity suggested the possible [Hey, 1946], the understanding and prediction of solar events that might produce interfering noiseStatistics of solar microwave radio burst spectra with implications for operations of microwave

  18. Microwave photochemistry. Photoinitiated radical addition of tetrahydrofuran to peruorohexylethene under microwave irradiation

    E-Print Network [OSTI]

    Cirkva, Vladimir

    ¯uorohexylethene under microwave irradiation VladimõÂr CõÂrkva, Milan HaÂjek* Institute of Chemical Process Fundamentals combined irradiation using a new simple photochemical reactor developed for organic synthetic reactions reserved. Keywords: Radical addition; Microwave irradiation; Photoinitiation; Electrodeless UV lamp

  19. Planck 2015 results. XI. CMB power spectra, likelihoods, and robustness of parameters

    E-Print Network [OSTI]

    Aghanim, N; Ashdown, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bock, J J; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bucher, M; Burigana, C; Butler, R C; Calabrese, E; Cardoso, J -F; Catalano, A; Challinor, A; Chiang, H C; Christensen, P R; Clements, D L; Colombo, L P L; Combet, C; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Désert, F -X; Di Valentino, E; Dickinson, C; Diego, J M; Dolag, K; Dole, H; Donzelli, S; Doré, O; Douspis, M; Ducout, A; Dunkley, J; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Fergusson, J; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Gauthier, C; Gerbino, M; Giard, M; Gjerløw, E; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Hamann, J; Hansen, F K; Harrison, D L; Helou, G; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Holmes, W A; Hornstrup, A; Huffenberger, K M; Hurier, G; Jaffe, A H; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kiiveri, K; Knoche, J; Knox, L; Kunz, M; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J -M; Lasenby, A; Lattanzi, M; Lawrence, C R; Jeune, M Le; Leonardi, R; Lesgourgues, J; Levrier, F; Lewis, A; Liguori, M; Lilje, P B; Lilley, M; Linden-Vørnle, M; Lindholm, V; López-Caniego, M; Macías-Pérez, J F; Maffei, B; Maggio, G; Maino, D; Mandolesi, N; Mangilli, A; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Meinhold, P R; Melchiorri, A; Migliaccio, M; Millea, M; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Narimani, A; Naselsky, P; Nati, F; Natoli, P; Noviello, F; Novikov, D; Novikov, I; Oxborrow, C A; Paci, F; Pagano, L; Pajot, F; Paoletti, D; Partridge, B; Pasian, F; Patanchon, G; Pearson, T J; Perdereau, O; Perotto, L; Pettorino, V; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Ristorcelli, I; Rocha, G; Rossetti, M; Roudier, G; d'Orfeuil, B Rouillé; Rubiño-Martín, J A; Rusholme, B; Salvati, L; Sandri, M; Santos, D; Savelainen, M; Savini, G; Scott, D; Serra, P; Spencer, L D; Spinelli, M; Stolyarov, V; Stompor, R; Sunyaev, R; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Toffolatti, L; Tomasi, M; Tristram, M; Trombetti, T; Tucci, M; Tuovinen, J; Umana, G; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Wehus, I K; Yvon, D; Zacchei, A; Zonca, A

    2015-01-01

    This paper presents the Planck 2015 likelihoods, statistical descriptions of the 2-point correlation functions of CMB temperature and polarization. They use the hybrid approach employed previously: pixel-based at low multipoles, $\\ell$, and a Gaussian approximation to the distribution of cross-power spectra at higher $\\ell$. The main improvements are the use of more and better processed data and of Planck polarization data, and more detailed foreground and instrumental models. More than doubling the data allows further checks and enhanced immunity to systematics. Progress in foreground modelling enables a larger sky fraction, contributing to enhanced precision. Improvements in processing and instrumental models further reduce uncertainties. Extensive tests establish robustness and accuracy, from temperature, from polarization, and from their combination, and show that the {\\Lambda}CDM model continues to offer a very good fit. We further validate the likelihood against specific extensions to this baseline, suc...

  20. BEDES Background | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels DataEnergy Webinar:I Due DateOpportunityManual Audit»Background BEDES

  1. Numerical simulations of output pulse extraction from a high-power microwave compressor with a plasma switch

    SciTech Connect (OSTI)

    Shlapakovski, Anatoli; Beilin, Leonid; Bliokh, Yuri; Donskoy, Moshe; Krasik, Yakov E. [Physics Department, Technion, Haifa 32000 (Israel); Hadas, Yoav [Department of Applied Physics, Rafael, PO Box 2250, Haifa 31021 (Israel); Schamiloglu, Edl [Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2014-05-07

    Numerical simulations of the process of electromagnetic energy release from a high-power microwave pulse compressor comprising a gas-filled cavity and interference switch were carried out. A microwave plasma discharge in a rectangular waveguide H-plane tee was modeled with the use of the fully electromagnetic particle-in-cell code MAGIC. The gas ionization, plasma evolution, and interaction with RF fields accumulated within the compressor were simulated using different approaches provided by the MAGIC code: particle-in-cell approach accounting for electron-neutral collisions, gas conductivity model based on the concept of mobility, and hybrid modeling. The dependences of the microwave output pulse peak power and waveform on parameters that can be controlled in experiments, such as an external ionization rate, RF field amplitude, and background gas pressure, were investigated.

  2. Applications for Microwave Generators in the Process Industries 

    E-Print Network [OSTI]

    Humphrey, J. L.; Vasilakos, N. P.

    1983-01-01

    Microwaves find widespread use in radar applications, in telephonic communications, and in the generation of thermal energy for heating. It is this last use that is of interest here. The use of microwave generators to dry heat-sensitive materials...

  3. Microwave imaging reflectometry for the visualization of turbulence in tokamaks

    E-Print Network [OSTI]

    Mazzucato, Ernesto

    Microwave imaging reflectometry for the visualization of turbulence in tokamaks E. Mazzucato describes the results of an extensive numerical study of microwave reflectometry in tokamaks showing scheme for the global visualization of turbulent fluctuations in tokamaks is described. 1. Introduction

  4. Microwave off-gas treatment apparatus and process

    DOE Patents [OSTI]

    Schulz, Rebecca L. (Aiken, SC); Clark, David E. (Gainesville, FL); Wicks, George G. (North Aiken, SC)

    2003-01-01

    The invention discloses a microwave off-gas system in which microwave energy is used to treat gaseous waste. A treatment chamber is used to remediate off-gases from an emission source by passing the off-gases through a susceptor matrix, the matrix being exposed to microwave radiation. The microwave radiation and elevated temperatures within the combustion chamber provide for significant reductions in the qualitative and quantitative emissions of the gas waste stream.

  5. Low Background Counting At SNOLAB

    SciTech Connect (OSTI)

    Lawson, Ian; Cleveland, Bruce [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)

    2011-04-27

    It is a continuous and ongoing effort to maintain radioactivity in materials and in the environment surrounding most underground experiments at very low levels. These low levels are required so that experiments can achieve the required detection sensitivities for the detection of low-energy neutrinos, searches for dark matter and neutrinoless double-beta decay. SNOLAB has several facilities which are used to determine these low background levels in the materials and the underground environment. This proceedings will describe the SNOLAB High Purity Germanium Detector which has been in continuous use for the past five years and give results of many of the items that have been counted over that period. Brief descriptions of SNOLAB's alpha-beta and electrostatic counters will be given, and the radon levels at SNOLAB will be discussed.

  6. Low background aspects of GERDA

    SciTech Connect (OSTI)

    Simgen, Hardy [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2011-04-27

    The GERDA experiment operates bare Germanium diodes enriched in {sup 76}Ge in an environment of pure liquid argon to search for neutrinoless double beta decay. A very low radioactive background is essential for the success of the experiment. We present here the research done in order to remove radio-impurities coming from the liquid argon, the stainless steel cryostat and the front-end electronics. We found that liquid argon can be purified efficiently from {sup 222}Rn. The main source of {sup 222}Rn in GERDA is the cryostat which emanates about 55 mBq. A thin copper shroud in the center of the cryostat was implemented to prevent radon from approaching the diodes. Gamma ray screening of radio-pure components for front-end electronics resulted in the development of a pre-amplifier with a total activity of less than 1 mBq {sup 228}Th.

  7. Constraints on the polarization purity of a Stokes microwave radiometer

    E-Print Network [OSTI]

    Ruf, Christopher

    Constraints on the polarization purity of a Stokes microwave radiometer Christopher S. Ruf of the third and fourth Stokes parameters of microwave thermal emission can be degraded by nonideal radiometer of microwave emission by the ocean surface identified wind direc- tion as the cause [Bespalova et al., 1982

  8. Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment A. Boxer, J. Kesner a multi-channel microwave interferometer. Such a device makes use the relationship between a plasma;Basic Design · An RF of 60 GHz puts our interferometer in the microwave spectrum. · The primary design

  9. Microwave frequency measurement with improved measurement range and

    E-Print Network [OSTI]

    Yao, Jianping

    Microwave frequency measurement with improved measurement range and resolution X. Zou and J. Yao An approach is proposed and demonstrated to improve the measure- ment range and resolution of a microwave frequency measurement system. Two optical wavelengths are modulated by a microwave signal in a Mach

  10. Quantitative Microwave Imaging Based on a Huber regularization

    E-Print Network [OSTI]

    Pizurica, Aleksandra

    Quantitative Microwave Imaging Based on a Huber regularization Funing Bai, Wilfried Philips University, Belgium Abstract--Reconstruction of inhomogeneous dielectric objects from microwave scattering by means of quantitative microwave tomography is a nonlinear, ill-posed inverse problem. In this paper, we

  11. A NOVEL MICROWAVE CAMERA FOR NDE OF CONCRETE STRUCTURES

    E-Print Network [OSTI]

    De Flaviis, Franco

    A NOVEL MICROWAVE CAMERA FOR NDE OF CONCRETE STRUCTURES By Maria Q. Feng1 , Yoo Jin Kim2 , Franco a novel microwave camera for detecting and quantitatively assessing such internal damage in concrete. For the experimental verification, a prototype planar microwave camera was fabricated and tested on a concrete block

  12. MICROWAVE IMAGING REFLECTOMETRY FOR THE VISUALIZATION OF TURBULENCE IN TOKAMAKS

    E-Print Network [OSTI]

    1 MICROWAVE IMAGING REFLECTOMETRY FOR THE VISUALIZATION OF TURBULENCE IN TOKAMAKS E. Mazzucato of density fluctuations in tokamaks. The proposed method is based on microwave reflectometry and consists, and forming an image of the reflecting plasma layer onto a 2D array of microwave receivers. Based on results

  13. EE 402 Microwave and RF Circuits Aqeel Ahmad Qureshi

    E-Print Network [OSTI]

    Saskatchewan, University of

    EE 402 Microwave and RF Circuits Aqeel Ahmad Qureshi aqeel.ahmad@usask.ca Objective: There is currently an explosion in wireless communications at microwave and millimeter-wave frequencies, for both-effective and highly integrated devices and circuits are required. An understanding of modern microwave theory

  14. Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment A. Boxer, J. Kesner design follows other microwave interferometers in the literature, in particular C.W. Domier et. al. Rev.Sci.Instrum. 59 [1988], 1588 · An RF beam of 60 GHz puts our interferometer in the microwave spectrum. · Our

  15. Apparatus for microwave heat treatment of manufactured components

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN)

    2008-04-15

    An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

  16. Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment A. Boxer, J. Kesner the density profile of the plasma in LDX, we are constructing a multi-channel microwave interferometer be inverted to reconstruct a radially symmetric density profile. The microwave interferometer of LDX

  17. Preliminary Validation and Performance of the Jason Microwave Radiometer

    E-Print Network [OSTI]

    Ruf, Christopher

    Preliminary Validation and Performance of the Jason Microwave Radiometer Shannon Brown and Chris Pasadena, CA Abstract ­ The Jason Microwave Radiometer is calibrated using hot and cold on-located Topex Microwave Radiometer and radiosonde values. The calibrated path delay values are demonstrated

  18. VICARIOUS CALIBRATION OF GLOBAL PRECIPITATION MEASUREMENT MICROWAVE RADIOMETERS1

    E-Print Network [OSTI]

    Ruf, Christopher

    VICARIOUS CALIBRATION OF GLOBAL PRECIPITATION MEASUREMENT MICROWAVE RADIOMETERS1 Darren Mc of the TMI, WindSat, SSM/I F13 and SSM/I F14 microwave radiometers using data from the GPM Inter Terms-- Microwave radiometry, Calibration 1. INTRODUCTION The primary goal of NASA's Global

  19. MICROWAVE PROCESSING OF LUNAR SOIL Lawrence A. Taylor1

    E-Print Network [OSTI]

    Taylor, Lawrence A.

    MICROWAVE PROCESSING OF LUNAR SOIL Lawrence A. Taylor1 and Thomas T. Meek2 The unique properties of lunar regolith make for the extreme coupling of the soil to microwave radiation. Space weathering lunar soil (i.e., 1200-1500 o C) in minutes in a normal kitchen-type 2.45 GHz microwave, almost as fast

  20. Methods for microwave heat treatment of manufactured components

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN)

    2010-08-03

    An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

  1. CONTROLLED THERMONUCLEAR PROCESSES THE APPLICATION OF MICROWAVE TECHNIQUES

    E-Print Network [OSTI]

    MATT-I7 CONTROLLED THERMONUCLEAR PROCESSES THE APPLICATION OF MICROWAVE TECHNIQUES f TO STELLARATOR-11 .. · The Application of Microwave Techniques to Ste11arator Research Mark A. Heald August 26, 1959 Abstract .. This report summarizes the basic principles of microwave diagnostics as applied

  2. Tunable photonic microwave generation using optically injected semiconductor

    E-Print Network [OSTI]

    Chan, Sze-Chun

    Tunable photonic microwave generation using optically injected semiconductor laser dynamics feedback are investigated for photonic microwave generation. The optical injection first drives the laser into P1 dynamics so that its intensity oscillates at a microwave frequency. A dual-loop optical feedback

  3. A direct digital synthesis chirped pulse Fourier transform microwave spectrometer

    E-Print Network [OSTI]

    Blake, Geoffrey

    A direct digital synthesis chirped pulse Fourier transform microwave spectrometer Ian A. Finneran OF SCIENTIFIC INSTRUMENTS 84, 083104 (2013) A direct digital synthesis chirped pulse Fourier transform microwave pulse Fourier transform microwave (CP-FTMW) spectrometers have become the instrument of choice

  4. Thermite powder ignition by localized microwaves Yehuda Meir, Eli Jerby

    E-Print Network [OSTI]

    Jerby, Eli

    Thermite powder ignition by localized microwaves Yehuda Meir, Eli Jerby Faculty of Engineering Keywords: Thermite Microwave heating Hotspots Thermal runaway Ignition a b s t r a c t This paper presents a new method to ignite pure thermite powder by low-power microwaves ($100 W). In this method

  5. Microwave and hard X-ray imaging observations of

    E-Print Network [OSTI]

    White, Stephen

    Microwave and hard X-ray imaging observations of energetic electrons in solar flares: event of 2003 to nonthermal energies are seen via microwave and hard X-ray emission from the solar corona. Imaging sophisticated and fully dedicated solar radio telescope operating at microwave frequencies (17 & 34 GHz) capable

  6. THZ TRANSMISSION SPECTROSCOPY APPLIED TO DIELECTRICS AND MICROWAVE CERAMICS

    E-Print Network [OSTI]

    KuÂ?el, Petr

    THZ TRANSMISSION SPECTROSCOPY APPLIED TO DIELECTRICS AND MICROWAVE CERAMICS ALEXEJ PASHKIN, ELENA of Ba(Mg1/3Ta2/3)O3 (BMT) high-permittivity microwave ceramics was measured in the sub; time-resolved spectroscopy; microwave ceramics INTRODUCTION The method of time-domain terahertz

  7. Effect of microwave radiation on coal flotation

    SciTech Connect (OSTI)

    Ozbayoglu, G.; Depci, T.; Ataman, N. [Middle East Technical University, Ankara (Turkey). Mining Engineering Department

    2009-07-01

    Most low-rank coals are high in moisture and acid functional groups, therefore showing poor floatability. Drying, which removes the water molecules trapped in the pores and adsorbed at the surface of coal, decreases the hydrophilic character and improves the floatability. Microwave heating, whose simplest application is drying, was applied at 0.9 kW power level for 60 sec exposure time in the experiments to decrease the moisture content of coal in order to enhance the hydrophobicity. The flotation tests of microwave-treated coal by using heptanol and octanol lead to a higher flotation yield and ash removal than original coal.

  8. Microwave gas breakdown in elliptical waveguides

    SciTech Connect (OSTI)

    Koufogiannis, I. D.; Sorolla, E., E-mail: eden.sorolla@epfl.ch; Mattes, M. [École Polytechnique Fédérale de Lausanne, Laboratoire d’Électromagnétisme et d'Acoustique (LEMA), Station 11, CH-1015 Lausanne (Switzerland)] [École Polytechnique Fédérale de Lausanne, Laboratoire d’Électromagnétisme et d'Acoustique (LEMA), Station 11, CH-1015 Lausanne (Switzerland)

    2014-01-15

    This paper analyzes the microwave gas discharge within elliptical waveguides excited by the fundamental mode. The Rayleigh-Ritz method has been applied to solve the continuity equation. The eigenvalue problem defined by the breakdown condition has been solved and the effective diffusion length of the elliptical waveguide has been calculated, what is used to find the corona threshold. This paper extends the microwave breakdown model developed for circular waveguides and shows the better corona withstanding capabilities of elliptical waveguides. The corona breakdown electric field threshold obtained with the variational method has been compared with the one calculated with the Finite Elements Method, showing excellent agreement.

  9. Synthesis of ultrafine powders by microwave heating

    DOE Patents [OSTI]

    Meek, T.T.; Sheinberg, H.; Blake, R.D.

    1987-04-24

    A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has dissolved. The resulting material is an ultrafine powder. This method can be used to make Al/sub 2/O/sub 3/, NiO /plus/ Al/sub 2/O/sub 3/ and NiO as well as a number of other materials including GaBa/sub 2/Cu/sub 3/O/sub x/. 1 tab.

  10. Synthesis of ultrafine powders by microwave heating

    DOE Patents [OSTI]

    Meek, Thomas T. (Knoxville, TN); Sheinberg, Haskell (Los Alamos, NM); Blake, Rodger D. (Santa Fe, NM)

    1988-01-01

    A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has been removed. The resulting material is an ultrafine powder. This method can be used to make Al.sub.2 O.sub.3, NiO+Al.sub.2 O.sub.3 and NiO as well as a number of other materials including GaBa.sub.2 Cu.sub.3 O.sub.x.

  11. ANOMALOUS ANISOTROPIC CROSS-CORRELATIONS BETWEEN WMAP CMB MAPS AND SDSS GALAXY DISTRIBUTION AND IMPLICATIONS ON THE DARK FLOW SCENARIO

    SciTech Connect (OSTI)

    Li Zhigang; Chen Xuelei [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Science, Beijing 100012 (China); Zhang Pengjie, E-mail: zgli@bao.ac.cn, E-mail: pjzhang@shao.ac.cn, E-mail: xuelei@cosmology.bao.ac.cn [Key Laboratory for Research in Galaxies and Cosmology, Shang Astronomical Observatory, Nandan Road 80, Shanghai 200030 (China)

    2012-10-20

    We search for the dark flow induced diffuse kinetic Sunyaev-Zel'dovich (kSZ) effect through CMB-galaxy cross-correlation. Such angular correlation is anisotropic, with a unique cos ({theta}{sub DF}) angular dependence, and hence can be distinguished from other components. Here, {theta}{sub DF} is the angle between the opposite dark flow direction and the direction of the sky where the correlation is measured. We analyze the KIAS-VAGC galaxy catalog of SDSS-DR7 and the WMAP seven-year temperature maps, applying an unbiased optimal weighting scheme to eliminate any statistically isotropic components and to enhance the dark flow detection signal. Non-zero weighted cross-correlations are detected at 3.5 {sigma} for the redshift bin z < 0.1 and at 3 {sigma} for the bin 0.1 < z < 0.2, implying the existence of statistically anisotropic components in CMB. However, further analysis does not support the dark flow explanation. The observed directional dependence deviates from the {proportional_to}cos {theta}{sub DF} relation expected, and hence cannot be explained by the presence of a single dark flow, and if the observed cross-correlation is generated by the dark flow induced kSZ effect, the velocity would be too high ({approx}> 6000 km s{sup -1}). We report this work as the first attempt to search for dark flow through weighted CMB-galaxy cross-correlation and to draw the attention on the sources of the detected anomalous CMB-galaxy cross-correlation.

  12. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3269 Tunable Programmable Microwave Photonic Filters

    E-Print Network [OSTI]

    Purdue University

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3269 Tunable Programmable Microwave Photonic Filters Based on an Optical Frequency Comb Ehsan Hamidi, Student Member, IEEE the application of optical combs to implement tunable programmable microwave photonic filters. We design well

  13. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 59, NO. 11, NOVEMBER 2011 2987 Frequency-Tunable Microwave Generation

    E-Print Network [OSTI]

    Yao, Jianping

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 59, NO. 11, NOVEMBER 2011 2987 Frequency-Tunable Microwave Generation Based on Time-Delayed Optical Combs Montasir Qasymeh, Wangzhe Li, Student Member, IEEE, and Jianping Yao, Senior Member, IEEE Abstract--A novel approach to generating a frequency-tun- able microwave

  14. 804 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 54, NO. 2, FEBRUARY 2006 Photonic Generation of Microwave Signal Using

    E-Print Network [OSTI]

    Yao, Jianping

    804 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 54, NO. 2, FEBRUARY 2006 Photonic Generation of Microwave Signal Using a Dual-Wavelength Single-Longitudinal-Mode Fiber Ring Laser Xiangfei of high-fre- quency microwave signals using a dual-wavelength single-longitu- dinal-mode fiber ring laser

  15. 3470 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 61, NO. 9, SEPTEMBER 2013 Photonic-Assisted Microwave Channelizer With

    E-Print Network [OSTI]

    Yao, Jianping

    3470 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 61, NO. 9, SEPTEMBER 2013 Photonic-Assisted Microwave Channelizer With Improved Channel Characteristics Based on Spectrum-Controlled Stimulated, Senior Member, IEEE, and Jianping Yao, Fellow, IEEE Abstract--A photonic-assisted microwave channelizer

  16. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 39, NO. 12, DECEMBER 1991 1931 Aperture Synthesis Concepts in Microwave

    E-Print Network [OSTI]

    Ruf, Christopher

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 39, NO. 12, DECEMBER 1991 1931 Aperture Synthesis Concepts in Microwave Remote Sensing of the Earth Calvin T. Swift, Fellow, IEEE, David M. Le of magnitude overwhat is presently achieved by microwave imaging systems that are collecting data from earth

  17. 422 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 19, NO. 6, JUNE 2009 Instantaneous Microwave Frequency Measurement

    E-Print Network [OSTI]

    Yao, Jianping

    422 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 19, NO. 6, JUNE 2009 Instantaneous Microwave Frequency Measurement Using an Optical Phase Modulator Xiaomin Zhang, Hao Chi, Xianmin Zhang technique for instantaneous microwave fre- quency measurement using an optical phase modulator is proposed

  18. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3279 Nonuniformly Spaced Photonic Microwave

    E-Print Network [OSTI]

    Yao, Jianping

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 11, NOVEMBER 2010 3279 Nonuniformly Spaced Photonic Microwave Delay-Line Filters and Applications Yitang Dai and Jianping Yao, Senior Member, IEEE Abstract--A finite impulse response (FIR) filter for microwave signal processing implemented

  19. 4002 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 54, NO. 11, NOVEMBER 2006 Programmable Photonic Microwave Filters With

    E-Print Network [OSTI]

    Purdue University

    4002 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 54, NO. 11, NOVEMBER 2006 Programmable Photonic Microwave Filters With Arbitrary Ultra-Wideband Phase Response Shijun Xiao, Member, IEEE for synthesis of programmable microwave phase filters over an ultra-wideband. Our scheme relies

  20. Degree-scale anomalies in the CMB: Localizing the first peak dip to a small patch of the north ecliptic sky

    SciTech Connect (OSTI)

    Yoho, Amanda [CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079 (United States); Ferrer, Francesc [Physics Department and McDonnell Center for the Space Sciences, Washington University, St Louis, Missouri 63130 (United States); Starkman, Glenn D. [CERCA/ISO, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079 (United States)

    2011-04-15

    Noticeable deviations from the prediction of the fiducial lambda cold dark matter cosmology are found in the angular power spectrum of the cosmic microwave background. Besides large-angle anomalies, the WMAP first year data revealed a dip in the power spectrum at l{approx}200, which seemed to disappear in the third year and subsequent angular power spectra. Using the WMAP single first, third, and fifth year data as well as the total 5 yr coadded data, we study the intensity and spatial distribution of this feature in order to unveil its origin and its implications for the cosmological parameters. We show that in the 5 yr coadded WMAP data release there is a suppression of the first Doppler peak in a region near the north ecliptic pole at a significance level between 99% and 96% depending on the weighting scheme that is considered.

  1. DarkLight radiation backgrounds

    SciTech Connect (OSTI)

    Kalantarians, Narbe [University of Texas

    2013-11-01

    We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-on, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW CW beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, field emission inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation.

  2. DarkLight radiation backgrounds

    SciTech Connect (OSTI)

    Kalantarians, N. [Department of Physics, Hampton University, Hampton VA 23668 (United States); Collaboration: DarkLight Collaboration

    2013-11-07

    We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-on, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW CW beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, field emission inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation.

  3. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1995-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  4. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, L.A.

    1995-11-14

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

  5. Simple Microwave Method for Detecting Water Holdup

    E-Print Network [OSTI]

    Iqbal, Sheikh Sharif

    combinations of oil and water contents. The #12;reflection responses (S11) of the pipe with water level rangingSimple Microwave Method for Detecting Water Holdup Sheikh S. I., Alqurashi K. Y., Ragheb H to determine the water holdup of a near horizontal oil carrying pipeline. This technique is particularly useful

  6. Planar controlled zone microwave plasma system

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxvlle, TN)

    2011-10-04

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  7. Microwave and Terahertz wave sensing with metamaterials

    E-Print Network [OSTI]

    Zhang, Xin

    Microwave and Terahertz wave sensing with metamaterials Hu Tao,1 Emil A. Kadlec,2 Andrew C designed, fabricated, and characterized metamaterial enhanced bimaterial cantilever pixels for far codes: (160.3918) Metamaterials; (040.2235) Detectors, Far infrared or terahertz; (050.6875) Three

  8. Microwave Sensors Active and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    Chapter 6 Microwave Sensors ­ Active and Passive David G. Long Electrical and Computer Engineering Department Brigham Young University Center for Remote Sensing 459 Clyde Building, Provo, UT 84602, long be classified as either passive (radiometers) or active (radars). Each sensor class provides unique insight

  9. Environmental assessment: South microwave communication facilities

    SciTech Connect (OSTI)

    Not Available

    1989-06-01

    Western Area Power Administration (Western) is proposing to construct, operate, and maintain eight microwave repeater stations in southwestern Colorado, southeastern Utah, and northern Arizona, in order to meet the minimum fade criteria established by the Western Systems Coordinating Council (WSCC) for the operation and protection of electric power systems. The proposed microwave facilities would increase the reliability of communication. This environmental assessment (EA) describes the existing environmental conditions and the impacts from construction of the eight microwave communication facilities. The EA was prepared in compliance with the National Environmental Policy Act of 1969, the Council on Environmental Quality Regulations (40 CFR 1500-1508), and the Department of Energy Guidelines (52 FR 47662, December 15, 1987). The proposed project would consist of constructing eight microwave facilities, each of which would include a self-supported lattice tower, an equipment building, a propane tank, distribution lines to provide electric power to the sites, and access roads to the sites. The facilities would be constructed in San Miguel and Montezuma Counties in Colorado, San Juan County, Utah, and Navajo, Apache, Coconino, and Yavapai Counties in Arizona. 20 refs., 2 figs., 2 tabs.

  10. Analysis of characteristic of microwave regeneration for diesel particulate filter

    SciTech Connect (OSTI)

    Ning Zhi; Zhang Guanglong; Lu Yong; Liu Junmin; Gao Xiyan; Liang Iunhui; Chen Jiahua [Dalian Univ. of Technology (China)

    1995-12-31

    The mathematical model for the microwave regeneration of diesel particulate filter is proposed according to the characteristic of microwave regeneration process. The model is used to calculate the temperature field, distribution of particulate and density field of oxygen in the filter during the process of regeneration with typical ceramic foam particulate filter data. The parametric study demonstrates how some of the main parameters, such as microwave attenuation constant of the filter, filter particulate loading, the power and distribution of microwave energy and so on, affect the efficiency of regeneration, the maximum filter temperature and regeneration duration. The results show that it is possible to regenerate the diesel particulate filters in certain conditions by using microwave energy. This paper can give one a whole understanding to several main factors that have effects on the process of microwave regeneration and provide a theoretical basis for the optimal design of the microwave regeneration system.

  11. Measuring the tensor to scalar ratio from CMB B-modes in presence of foregrounds

    E-Print Network [OSTI]

    Betoule, Marc; Delabrouille, J; Jeune, M Le; Cardoso, Jean-François

    2009-01-01

    Abreg: We investigate the impact of polarized foreground emission on the performances of future CMB experiments in measuring the tensor-to-scalar ratio r. We design a component separation pipeline, based on the Smica method, aimed at estimating r and the foreground contamination from the data with no prior assumption on the frequency dependence or spatial distribution of the foregrounds. We derive error bars accounting for the uncertainty on foreground contribution. We use the current knowledge of galactic and extra-galactic foregrounds as implemented in the Planck Sky Model (PSM), to build simulations of the sky emission for various experimental setups. Our method, permits us to detect r = 0.1 at more than 3 sigma from B-modes only with Planck data, and r = 0.001 at 6 sigma for the most ambitious designs of the future EPIC probe. We find that all-sky experiments permit a proper measurement of the reionization bump despite the large scale foreground emission and are nearly insensitive to contamination from po...

  12. A String-Inspired Model for the Low-$\\ell$ CMB

    E-Print Network [OSTI]

    Kitazawa, N

    2015-01-01

    We present a semi--analytic exploration of some low--$\\ell$ angular power spectra inspired by "Brane Supersymmetry Breaking". This mechanism splits Bose and Fermi excitations in String Theory, leaving behind an exponential potential that is just too steep for the inflaton to emerge from the initial singularity while descending it. As a result, the scalar generically bounces against the exponential wall, which typically introduces an infrared depression and a pre--inflationary peak in the power spectrum of scalar perturbations. We elaborate on a possible link between this phenomenon and the low--$\\ell$ CMB. For the first 32 multipoles, combining the hard exponential with a milder one leading to $n_s\\simeq 0.96$ and with a small gaussian bump we have attained a reduction of $\\chi^{\\,2}$ to about 46% of the standard $\\Lambda$CDM setting, with both WMAP9 and PLANCK 2013 data. This result corresponds to a $\\chi^{\\,2}/DOF$ of about 0.45, to be compared with a $\\Lambda$CDM value of about 0.85. The preferred choices ...

  13. A String-Inspired Model for the Low-$\\ell$ CMB

    E-Print Network [OSTI]

    N. Kitazawa; A. Sagnotti

    2015-06-06

    We present a semi--analytic exploration of some low--$\\ell$ angular power spectra inspired by "Brane Supersymmetry Breaking". This mechanism splits Bose and Fermi excitations in String Theory, leaving behind an exponential potential that is just too steep for the inflaton to emerge from the initial singularity while descending it. As a result, the scalar generically bounces against the exponential wall, which typically introduces an infrared depression and a pre--inflationary peak in the power spectrum of scalar perturbations. We elaborate on a possible link between this phenomenon and the low--$\\ell$ CMB. For the first 32 multipoles, combining the hard exponential with a milder one leading to $n_s\\simeq 0.96$ and with a small gaussian bump we have attained a reduction of $\\chi^{\\,2}$ to about 46% of the standard $\\Lambda$CDM setting, with both WMAP9 and PLANCK 2013 data. This result corresponds to a $\\chi^{\\,2}/DOF$ of about 0.45, to be compared with a $\\Lambda$CDM value of about 0.85. The preferred choices combine naturally quadrupole depression, a first peak around $\\ell=5$ and a wide minimum around $\\ell=20$. We have also gathered some evidence that similar spectra emerge if the hard exponential is combined with more realistic models of inflation. A problem of the preferred examples is their slow convergence to an almost scale--invariant profile.

  14. North-South non-Gaussian asymmetry in Planck CMB maps

    SciTech Connect (OSTI)

    Bernui, A.; Oliveira, A.F.; Pereira, T.S. E-mail: adhimar@unifei.edu.br

    2014-10-01

    We report the results of a statistical analysis performed with the four foreground-cleaned Planck maps by means of a suitably defined local-variance estimator. Our analysis shows a clear dipolar structure in Planck's variance map pointing in the direction (l,b) ? (220°,-32°), thus consistent with the North-South asymmetry phenomenon. Surprisingly, and contrary to previous findings, removing the CMB quadrupole and octopole makes the asymmetry stronger. Our results show a maximal statistical significance, of 98.1% CL, in the scales ranging from ?=4 to ?=500. Additionally, through exhaustive analyses of the four foreground-cleaned and individual frequency Planck maps, we find unlikely that residual foregrounds could be causing this dipole variance asymmetry. Moreover, we find that the dipole gets lower amplitudes for larger masks, evidencing that most of the contribution to the variance dipole comes from a region near the galactic plane. Finally, our results are robust against different foreground cleaning procedures, different Planck masks, pixelization parameters, and the addition of inhomogeneous real noise.

  15. Note: A novel design of a microwave feed for a microwave frequency standard with a linear ion trap

    SciTech Connect (OSTI)

    Zhang, J. W., E-mail: zhangjw@tsinghua.edu.cn; Miao, K.; Wang, S. G.; Wang, Z. B. [NIM-THU Joint Institute for Measurement Science (JMI), Tsinghua University, Beijing 100084 (China); Department of Precision Instrument, Tsinghua University, Beijing 100084 (China)

    2014-07-15

    Linear ion traps are important tools in many applications, particularly in mass spectrum analyzers and frequency standards. Here a novel design of a microwave feed integrated into one electrode of a linear quadrupole ion trap is demonstrated for the application of a microwave frequency standard based on cadmium ions. The mechanical structure of the microwave feed is compact and easy to build. The ion trap integrated with this microwave feed is successfully applied to measure the hyperfine splitting of the ground state of {sup 113}Cd{sup +}, thus demonstrating the practicality and reliability of the microwave feed.

  16. Gravitational clustering in Static and Expanding Backgrounds

    E-Print Network [OSTI]

    T. Padmanabhan

    2003-08-28

    A brief summary of several topics in the study of gravitational many body problem is given. The discussion covers both static backgrounds (applicable to astrophysical systems) as well as clustering in an expanding background (relevant for cosmology)

  17. INVESTIGATION Genomic Background and Generation Time

    E-Print Network [OSTI]

    Lynch, Michael

    INVESTIGATION Genomic Background and Generation Time Influence Deleterious Mutation Rates variation is generated and how selection shapes mutation rates over evolutionary time requires knowledge, genomic background and generation time, on deleterious mutation in Daphnia pulicaria, a cyclically

  18. Design and fabrication of InGaN/GaN heterojunction bipolar transistors for microwave power amplifiers

    E-Print Network [OSTI]

    Keogh, David Martin

    2006-01-01

    power, high efficiency microwave amplifiers. ” ProceedingsBipolar Transistors for Microwave Power Amplifiers by DavidBipolar Transistors For Microwave Power Amplifiers A

  19. Apparatus and method for microwave processing of materials

    DOE Patents [OSTI]

    Johnson, A.C.; Lauf, R.J.; Bible, D.W.; Markunas, R.J.

    1996-05-28

    Disclosed is a variable frequency microwave heating apparatus designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency heating apparatus is used in the method of the present invention to monitor the resonant processing frequency within the furnace cavity depending upon the material, including the state thereof, from which the workpiece is fabricated. The variable frequency microwave heating apparatus includes a microwave signal generator and a high-power microwave amplifier or a microwave voltage-controlled oscillator. A power supply is provided for operation of the high-power microwave oscillator or microwave amplifier. A directional coupler is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 10 figs.

  20. Apparatus and method for microwave processing of materials

    DOE Patents [OSTI]

    Johnson, Arvid C. (Lake in the Hills, IL); Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Markunas, Robert J. (Chapel Hill, NC)

    1996-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency heating apparatus (10) is used in the method of the present invention to monitor the resonant processing frequency within the furnace cavity (34) depending upon the material, including the state thereof, from which the workpiece (36) is fabricated. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a microwave voltage-controlled oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  1. Apparatus and method for microwave processing of materials using field-perturbing tool

    DOE Patents [OSTI]

    Tucker, Denise A. (Raleigh, NC); Fathi, Zakaryae (Cary, NC); Lauf, Robert J. (Oak Ridge, TN)

    2001-01-01

    A variable frequency microwave heating apparatus designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity for heating or other selected applications. A field-perturbing tool is disposed within the cavity to perturb the microwave power distribution in order to apply a desired level of microwave power to the workpiece.

  2. Study of Cosmogenic Neutron Backgrounds at LNGS

    E-Print Network [OSTI]

    Empl, A; Hungerford, E; Mosteiro, P

    2012-01-01

    Cosmic muon interactions are important contributors to backgrounds in underground detectors when searching for rare events. Typically neutrons dominate this background as they are particularly difficult to shield and detect in a veto system. Since actual background data is sparse and not well documented, simulation studies must be used to design shields and predict background rates. This means that validation of any simulation code is necessary to assure reliable results. This work studies the validation of the FLUKA simulation code, and reports the results of a simulation of cosmogenic background for a liquid argon two-phase detector embedded within a water tank and liquid scintillator shielding.

  3. On the significance of power asymmetries in Planck CMB data at all scales

    SciTech Connect (OSTI)

    Quartin, Miguel [Instituto de Física, Universidade Federal do Rio de Janeiro, 21941-972, Rio de Janeiro, RJ (Brazil); Notari, Alessio, E-mail: mquartin@if.ufrj.br, E-mail: notari@ffn.ub.es [Departament de Física Fondamental i Institut de Ciéncies del Cosmos, Universitat de Barcelona, Martí i Franqués 1, E-08028 Barcelona (Spain)

    2015-01-01

    We perform an analysis of the CMB temperature data taken by the Planck satellite investigating if there is any significant deviation from cosmological isotropy. We look for differences in the spectrum between two opposite hemispheres and also for dipolar modulations. We propose a new way to avoid biases due to partial-sky coverage by producing a mask symmetrized in antipodal directions, in addition to the standard smoothing procedure. We also properly take into account both Doppler and aberration effects due to our peculiar velocity and the anisotropy of the noise, since these effects induce a significant hemispherical asymmetry. We are thus able to probe scales all the way to ? = 2000. After such treatment we find no evidence for significant hemispherical anomalies along any of the analyzed directions (i.e. deviations are less than 1.5? when summing over all scales). Although among the larger scales there are sometimes higher discrepancies, these are always less than 3?. We also find results on a dipolar modulation of the power spectrum. Along the hemispheres aligned with the most asymmetric direction for 2 ? ? ? 2000 we find a 3.3? discrepancy when comparing to simulations. However, if we do not restrict ourselves to Planck's maximal asymmetry axis, which can only be known a posteriori, and compare Planck data with the modulation of simulations along their respective maximal asymmetry directions, the discrepancy goes down to less than 1? (with, again, almost 3? discrepancies in some low-? modes). We thus conclude that no significant power asymmetries seem to be present in the full data set. Interestingly, without proper removal of Doppler and aberration effects one would find spurious anomalies at high ?, between 3? and 5?. Even when considering only ? < 600 we find that the boost is non-negligible and alleviates the discrepancy by roughly half-?.

  4. Microwave-cut silicon layer transfer

    SciTech Connect (OSTI)

    Thompson, D.C.; Alford, T.L.; Mayer, J.W.; Hochbauer, T.; Nastasi, M.; Lau, S.S.; Theodore, N. David; Henttinen, K.; Suni, Ilkka; Chu, Paul K. [Department of Chemical and Materials Engineering, Arizona State University, Tempe, Arizona 85287-6006 (United States); Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); Department of Electrical and Computer Engineering, University of California at San Diego, San Diego, California 92093 (United States); Advanced Products Research and Development Laboratory, Freescale Semiconductor Incorporated, 2100 East Elliot Road, Tempe, Arizona 85284 (United States); VTT Centre for Microelectronics, P.O. Box 1208, 02044 VTT (Finland); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2005-11-28

    Microwave heating is used to initiate exfoliation of silicon layers in conjunction with the ion-cut process for transfer of silicon layers onto insulator or heterogeneous layered substrates. Samples were processed inside a 2.45 GHz, 1300 W cavity applicator microwave system for time durations as low as 12 s. This is a significant decrease in exfoliation incubation times. Sample temperatures measured by pyrometry were within previous published ranges. Rutherford backscattering spectrometry and cross-sectional transmission electron microscopy were used to determine layer thickness and crystallinity. Surface quality was measured by using atomic force microscopy. Hall measurements were used to characterize electrical properties as a function of postcut anneal time and temperature.

  5. Double-Slit Experiments with Microwave Billiards

    E-Print Network [OSTI]

    S. Bittner; B. Dietz; M. Miski-Oglu; P. Oria Iriarte; A. Richter; F. Schäfer

    2011-07-27

    Single and double-slit experiments are performed with two microwave billiards with the shapes of a rectangle, respectively, a quarter stadium. The classical dynamics of the former is regular, that of the latter is chaotic. Microwaves can leave the billiards via slits in the boundary, forming interference patterns on a screen. The aim is to determine the effect of the billiard dynamics on their structure. For this the development of a method for the construction of a directed wave packet by means of an array of multiple antennas was crucial. The interference patterns show a sensitive dependence not only on the billiard dynamics but also on the initial position and direction of the wave packet.

  6. Nonlinear multiferroic phase shifters for microwave frequencies

    SciTech Connect (OSTI)

    Ustinov, Alexey B.; Kalinikos, Boris A. [Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University, St. Petersburg 197376 (Russian Federation); Srinivasan, G. [Department of Physics, Oakland University, Rochester, Michigan 48309 (United States)

    2014-02-03

    A nonlinear microwave phase shifter based on a planar multiferroic composite has been studied. The multiferroic structure is fabricated in the form of a bilayer consisting of yttrium iron garnet and barium strontium titanate. The principle of operation of the device is based on the linear and nonlinear control of the phase shift of the hybrid spin-electromagnetic waves propagating in the bilayer. The linear control is realized with magnetic and electric fields. The nonlinear control is provided by the input power of microwave signal. The device showed a nonlinear phase shift up to 250°, electric field induced phase shift up to 330°, and magnetic field induced phase shift of more than 180°.

  7. Quantum and Wave Dynamical Chaos in Superconducting Microwave Billiards

    E-Print Network [OSTI]

    B. Dietz; A. Richter

    2015-04-17

    Experiments with superconducting microwave cavities have been performed in our laboratory for more than two decades. The purpose of the present article is to recapitulate some of the highlights achieved. We briefly review (i) results obtained with flat, cylindrical microwave resonators, so-called microwave billiards, concerning the universal fluctuation properties of the eigenvalues of classically chaotic systems with no, a threefold and a broken symmetry; (ii) summarize our findings concerning the wave-dynamical chaos in three-dimensional microwave cavities; (iii) present a new approach for the understanding of the phenomenon of dynamical tunneling which was developed on the basis of experiments that were performed recently with unprecedented precision, and finally, (iv) give an insight into an ongoing project, where we investigate universal properties of (artificial) graphene with superconducting microwave photonic crystals that are enclosed in a microwave resonator, i.e., so-called Dirac billiards.

  8. A container for heat treating materials in microwave ovens

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Kimrey, H.D. Jr.; Mills, J.E.

    1988-01-26

    The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed to top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation for reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achievable in the oven without the container.

  9. Joining of thermoplastic substrates by microwaves

    DOE Patents [OSTI]

    Paulauskas, Felix L. (Oak Ridge, TN); Meek, Thomas T. (Knoxville, TN)

    1997-01-01

    A method for joining two or more items having surfaces of thermoplastic material includes the steps of depositing an electrically-conductive material upon the thermoplastic surface of at least one of the items, and then placing the other of the two items adjacent the one item so that the deposited material is in intimate contact with the surfaces of both the one and the other items. The deposited material and the thermoplastic surfaces contacted thereby are then exposed to microwave radiation so that the thermoplastic surfaces in contact with the deposited material melt, and then pressure is applied to the two items so that the melted thermoplastic surfaces fuse to one another. Upon discontinuance of the exposure to the microwave energy, and after permitting the thermoplastic surfaces to cool from the melted condition, the two items are joined together by the fused thermoplastic surfaces. The deposited material has a thickness which is preferably no greater than a skin depth, .delta..sub.s, which is related to the frequency of the microwave radiation and characteristics of the deposited material in accordance with an equation.

  10. Non-thermal Cosmic Backgrounds and prospects for future high-energy observations of blazars

    E-Print Network [OSTI]

    P. Giommi; S. Colafrancesco

    2006-02-10

    We discuss the contribution of the blazar population to the extragalactic background radiation across the electromagnetic (e.m.) spectrum with particular reference to the microwave, hard-X-ray and gamma-ray bands. Our estimates are based on a recently derived blazar radio LogN-LogS that was built by combining several radio and multi-frequency surveys. We show that blazar emission integrated over cosmic time gives rise to a considerable broad-band non-thermal cosmic background that dominates the extragalactic brightness in the high-energy part of the e.m. spectrum. We also estimate the number of blazars that are expected to be detected by future planned or hypothetical missions operating in the X-ray and gamma-ray energy bands.

  11. dissociation in ArO surface-wave microwave discharges

    E-Print Network [OSTI]

    Guerra, Vasco

    O 2 dissociation in Ar­O 2 surface-wave microwave discharges This article has been downloaded from.1088/0022-3727/45/19/195205 O2 dissociation in Ar­O2 surface-wave microwave discharges Kinga Kutasi1 , Paulo A S´a2,3 and Vasco in Ar­O2 surface-wave microwave discharges. The dissociation degree of O2 molecules ([O]/2[O2

  12. Assessment of microwave power flow for reflectometry measurements in tokamak plasmas

    E-Print Network [OSTI]

    Gourdain, P-A; Peebles, W. A.

    2008-01-01

    of incident and reflected microwave rays for O-mode and X-Assessment of microwave power flow for reflectometryLos Angeles, CA 90095-1547 Microwave diagnostics, such as

  13. A Reconfigurable Microwave Photonic Channelized Receiver Based on Dense Wavelength Division Multiplexing Using an Optical Comb

    E-Print Network [OSTI]

    Yao, Jianping

    A Reconfigurable Microwave Photonic Channelized Receiver Based on Dense Wavelength Division, Hangzhou, 310027 China b Microwave Photonics Research Laboratory, School of Information Technology: Received 27 September 2011 Accepted 13 January 2012 Available online 30 January 2012 Keywords: Microwave

  14. Electrically detected magnetic resonance in a W-band microwave cavity

    E-Print Network [OSTI]

    Lang, V.

    2012-01-01

    resonance in a W-band microwave cavity V. Lang, 1, ? C. C.resonant W-band (94 GHz) microwave cavity. The advantages ofmagnetic ?elds and high microwave frequencies is therefore a

  15. Plasma and Beam Production Experiments with HYBRIS, a Microwave-assisted H- Ion

    E-Print Network [OSTI]

    Keller, R. AUTHOR-Kwan, S.; Hahto, S.; Regis, M.; Wallig, J.

    2006-01-01

    Experiments with HYBRIS, a Microwave-assisted H - Ionvoltage. The reflected microwave power, however, amounted toE lect(500 mA) Collector Microwave power (W) FIGURE 7. H -

  16. 1 Filter_Supplemental-Info_090913.doc Supplemental Information Regarding RF/Microwave Filter Design

    E-Print Network [OSTI]

    Weller/USF 1 Filter_Supplemental-Info_090913.doc Supplemental Information Regarding RF/Microwave Filter Design The video module on RF/microwave filter design, Filter Demonstration in Microwave Office

  17. A STUDY OF MICROWAVE INSTABILITIES BY MEANS OF A SQUARE-WELL POTENTIAL

    E-Print Network [OSTI]

    Kim, K.-J.

    2010-01-01

    a more realistic theory of microwave·~nstabi1ities.16-27, 1979 A STUDY OF MICROWAVE INSTABILITIES BY MEANS OF ABerkeley A Study of Microwave Instabilities by means of a

  18. Integrated microwave and millimeter-wave phased-array designs in silicon technologies

    E-Print Network [OSTI]

    Koh, Kwang-Jin

    2008-01-01

    RF/Microwave Phased-Array Design: X-/Ku-Band 8-ElementPhased-array Receiver,” Microwave Journal, vol. 50, no. 5,power divider,” IRE Trans. Microwave Theory & Tech. , vol.

  19. Linear, Low Noise Microwave Photonic Systems using Phase and Frequency Modulation

    E-Print Network [OSTI]

    Wyrwas, John Michael

    2012-01-01

    ii List of Figures Microwave photonics frequencies ofof signal propagation in a microwave photonic link. The out-optical FM-FDM Gb/s microwave PSK signals,” IEEE Photonics

  20. A Permanent-Magnet Microwave Ion Source for a Compact High-Yield Neutron Generator

    E-Print Network [OSTI]

    Waldmann, Ole

    2011-01-01

    A Permanent-Magnet Microwave Ion Source for a Compact High-A Permanent-Magnet Microwave Ion Source for a Compact High-on the development of a microwave ion source that will be

  1. Microwave Plasma Monitoring System For Real-Time Elemental Analysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    System Microwave Plasma Monitoring System For Real-Time Elemental Analysis The invention apparatus can also be used to monitor for the presence of halogens, sulfur and...

  2. Method and apparatus for thickness measurement using microwaves

    DOE Patents [OSTI]

    Woskov, Paul (Bedford, MA) [Bedford, MA; Lamar, David A. (West Richland, WA) [West Richland, WA

    2001-01-01

    The method for measuring the thickness of a material which transmits a detectable amount of microwave radiation includes irradiating the material with coherent microwave radiation tuned over a frequency range. Reflected microwave radiation is detected, the reflected radiation having maxima and minima over the frequency range as a result of coherent interference of microwaves reflected from reflecting surfaces of the material. The thickness of the material is determined from the period of the maxima and minima along with knowledge of the index of refraction of the material.

  3. New Energy Efficiency Standards for Microwave Ovens to Save Consumers...

    Broader source: Energy.gov (indexed) [DOE]

    today that the Energy Department has finalized new energy efficiency standards for microwave ovens that will save consumers nearly 3 billion on their energy bills through 2030....

  4. Applications of Substrate Integrated Waveguide (SIW) Structure in Microwave Engineering

    E-Print Network [OSTI]

    Shen, Zhi

    2015-01-01

    Constantine A. Advanced engineering electromagnetics. Vol.Structure in Microwave Engineering A thesis submitted inof Science in Electrical Engineering by Zhi Shen © Copyright

  5. Hanford Site background: Part 1, Soil background for nonradioactive analytes. Revision 1, Volume 2

    SciTech Connect (OSTI)

    Not Available

    1993-04-01

    Volume two contains the following appendices: Description of soil sampling sites; sampling narrative; raw data soil background; background data analysis; sitewide background soil sampling plan; and use of soil background data for the detection of contamination at waste management unit on the Hanford Site.

  6. High frequency background quantization of gravity

    SciTech Connect (OSTI)

    von Borzeszkowski, H.

    1982-06-01

    Considering background quantization of gravitational fields, it is generally assumed that the classical background satisfies Einstein's gravitational equations. However, there exist arguments showing that, for high frequency (quantum) fluctuations, this assumption has to be replaced by a condition describing the back reaction of fluctuations on the background. It is shown that such an approach leads to limitations for the quantum procedure which occur at distances larger than Planck's elementary length 1 = (Gh/c/sup 3/)/sup 1/2/.

  7. IDENTIFICATION OF BACKGROUND INTELLECTUAL PROPERTY (BIP)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    or is published copyrighted computer software; including minor modifications of such computer software. Background Patent means a patent covering an invention or discovery...

  8. Final Conservation Billing Credit Policy Supplement Background...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    December 17, 2014 Page 1 Final Conservation Billing Credit Policy Supplement Background and Need: This Conservation Billing Credit Policy Supplement describes how Bonneville Power...

  9. Radiometer System to Map the Cosmic Background Radiation

    E-Print Network [OSTI]

    Gorenstein, Marc V.; Muller, Richard A.; Smoot, George F.; Tyson, J. Anthony

    1977-01-01

    SYSTEM TO MAP THE COSMIC BACKGROUND RADIATION RECEIVEDSystem to Map the Cosmic Background Radiation* Marc V.

  10. MARSAME Appendix B B. SOURCES OF BACKGROUND RADIOACTIVITY

    E-Print Network [OSTI]

    : · The Nuclear Regulatory Commission (NRC) provides information concerning background radioactivity in Background

  11. The cross correlation between the 21-cm radiation and the CMB lensing field: a new cosmological signal

    SciTech Connect (OSTI)

    Vallinotto, Alberto

    2011-01-01

    The measurement of Baryon Acoustic Oscillations through the 21-cm intensity mapping technique at redshift z {<=} 4 has the potential to tightly constrain the evolution of dark energy. Crucial to this experimental effort is the determination of the biasing relation connecting fluctuations in the density of neutral hydrogen (HI) with the ones of the underlying dark matter field. In this work I show how the HI bias relevant to these 21-cm intensity mapping experiments can successfully be measured by cross-correlating their signal with the lensing signal obtained from CMB observations. In particular I show that combining CMB lensing maps from Planck with 21-cm field measurements carried out with an instrument similar to the Cylindrical Radio Telescope, this cross-correlation signal can be detected with a signal-to-noise (S/N) ratio of more than 5. Breaking down the signal arising from different redshift bins of thickness {Delta}z = 0.1, this signal leads to constraining the large scale neutral hydrogen bias and its evolution to 4{sigma} level.

  12. Chiral perturbation theory in a nuclear background

    E-Print Network [OSTI]

    Weise, Wolfram

    Chiral perturbation theory in a nuclear background L. Girlanda,a,* A. Rusetsky,a,b,1 and W. Weisea March 2004 Abstract We propose a novel way to formulate chiral perturbation theory (ChPT) in a nuclear in the background of the heavy nucleus at Oðp5 � in the chiral expansion, and to derive the leading terms

  13. M2-Branes and Background Fields

    E-Print Network [OSTI]

    Neil Lambert; Paul Richmond

    2009-08-20

    We discuss the coupling of multiple M2-branes to the background 3-form and 6-form gauge fields of eleven-dimensional supergravity, including the coupling of the Fermions. In particular we show in detail how a natural generalization of the Myers flux-terms, along with the resulting curvature of the background metric, leads to mass terms in the effective field theory.

  14. Broadband microwave burst produced by electron beams

    E-Print Network [OSTI]

    A. T. Altyntsev; G. D. Fleishman; G. -L. Huang; V. F. Melnikov

    2007-12-16

    Theoretical and experimental study of fast electron beams attracts a lot of attention in the astrophysics and laboratory. In the case of solar flares the problem of reliable beam detection and diagnostics is of exceptional importance. This paper explores the fact that the electron beams moving oblique to the magnetic field or along the field with some angular scatter around the beam propagation direction can generate microwave continuum bursts via gyrosynchrotron mechanism. The characteristics of the microwave bursts produced by beams differ from those in case of isotropic or loss-cone distributions, which suggests a new tool for quantitative diagnostics of the beams in the solar corona. To demonstrate the potentiality of this tool, we analyze here a radio burst occurred during an impulsive flare 1B/M6.7 on 10 March 2001 (AR 9368, N27W42). Based on detailed analysis of the spectral, temporal, and spatial relationships, we obtained firm evidence that the microwave continuum burst is produced by electron beams. For the first time we developed and applied a new forward fitting algorithm based on exact gyrosynchrotron formulae and employing both the total power and polarization measurements to solve the inverse problem of the beam diagnostics. We found that the burst is generated by a oblique beam in a region of reasonably strong magnetic field ($\\sim 200-300$ G) and the burst is observed at a quasi-transverse viewing angle. We found that the life time of the emitting electrons in the radio source is relatively short, $\\tau_l \\approx 0.5$ s, consistent with a single reflection of the electrons from a magnetic mirror at the foot point with the stronger magnetic field. We discuss the implications of these findings for the electron acceleration in flares and for beam diagnostics.

  15. Microwaves and particle accelerators: a fundamental link

    SciTech Connect (OSTI)

    Chattopadhyay, Swapan [Universities of Lancaster, Liverpool and Manchester and Cockcroft Institute, Cheshire (United Kingdom)

    2011-07-01

    John Cockcroft's splitting of the atom and Ernest Lawrence's invention of the cyclotron in the first half of the twentieth century ushered in the grand era of ever higher energy particle accelerators to probe deeper into matter. It also forged a link, bonding scientific discovery with technological innovation that continues today in the twenty first century. The development of radar and high power vacuum electronics, especially microwave power tubes like the magnetrons and the klystrons in the pre-second world war era, was instrumental in the rapid development of circular and linear charged particle accelerators in the second half of the twentieth century. We had harnessed the powerful microwave radio-frequency sources from few tens of MHz to up to 90 GHz spanning L-band to W-band frequencies. Simultaneously in the second half of the twentieth century, lasers began to offer very first opportunities of controlling charged particles at smaller resolutions on the scale of wavelengths of visible light. We also witnessed in this period the emergence of the photon and neutron sciences driven by accelerators built-by-design producing tailored and ultra-bright pulses of bright photons and neutrons to probe structure and function of matter from aggregate to individual molecular and atomic scales in unexplored territories in material and life sciences. As we enter the twenty first century, the race for ever higher energies, brightness and luminosity to probe atto-metric and atto-second domains of the ultra-small structures and ultra-fast processes continues. These developments depend crucially on yet further advancements in the production and control of high power and high frequency microwaves and light sources, often intricately coupled in their operation to the high energy beams themselves. We give a glimpse of the recent developments and innovations in the electromagnetic production and control of charged particle beams in the service of science and society. (author)

  16. or a long time, micro-wave engineers have

    E-Print Network [OSTI]

    Hagness, Susan C.

    College in Hanover, New Hampshire, USA. M.A. Stuchly is with the University of Victoria in Victoria outlook? More so than for any other cancers, breast tumors have electrical properties at microwave of new generations of microwave researchers despite strong competition from wireless communication

  17. Accuracy of an Atomic Microwave Power Standard (Conference digest)

    E-Print Network [OSTI]

    Paulusse, D C; Michaud, A; Paulusse, David C.; Rowell, Nelson L.; Michaud, Alain

    2004-01-01

    We have studied the accuracy of the atomic microwave power standard. The atoms are cooled and kept in a Magneto-Optical Trap (MOT), then dropped through a terminated transmission line (a rectangular, R-70 type, waveguide). The measurement of the internal atomic state allows an accurate determination of the transmitted microwave power.

  18. Scanning multichannel microwave radiometer snow water equivalent assimilation

    E-Print Network [OSTI]

    Walker, Jeff

    ,2 Jeffrey P. Walker,3 Paul R. Houser,4 and Chaojiao Sun2,5 Received 16 February 2006; revised 7 December. Citation: Dong, J., J. P. Walker, P. R. Houser, and C. Sun (2007), Scanning multichannel microwave; Rodell et al., 2004]. [3] Space-borne passive microwave sensors provide an alternate capability

  19. Microwave sintering of sol-gel derived abrasive grain

    DOE Patents [OSTI]

    Plovnick, Ross (St. Louis Park, MN); Celikkaya, Ahmet (Woodbury, MN); Blake, Rodger D. (Tuscon, AZ)

    1997-01-01

    A method is provided for making microwave-sintered, free flowing alpha alumina-based ceramic abrasive grain, under conditions effective to couple microwaves with calcined alpha alumina-based abrasive gain precursor and sinter it at a temperature of at least about 1150.degree. C.

  20. Microwave sintering of single plate-shaped articles

    DOE Patents [OSTI]

    Katz, Joel D. (Los Alamos, NM); Blake, Rodger D. (Tucson, AZ)

    1995-01-01

    Apparatus and method for high temperature sintering of plate-shaped articles of alumina, magnesia, silica, yttria, zirconia, and mixtures thereof using microwave radiation. An article is placed within a sintering structure located within a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.

  1. Microwave sintering of single plate-shaped articles

    DOE Patents [OSTI]

    Katz, J.D.; Blake, R.D.

    1995-07-11

    Apparatus and method are disclosed for high temperature sintering of plate-shaped articles of alumina, magnesia, silica, yttria, zirconia, and mixtures thereof using microwave radiation. An article is placed within a sintering structure located within a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled. 2 figs.

  2. Precision Cosmology and the Density of Baryons in the Universe

    E-Print Network [OSTI]

    M. Kaplinghat; M. S. Turner

    2000-11-14

    Big-bang Nucleosynthesis (BBN) and Cosmic Microwave Background (CMB) anisotropy measurements give independent, accurate measurements of the baryon density and can test the framework of the standard cosmology. Early CMB data are consistent with the longstanding conclusion from BBN that baryons constitute a small fraction of matter in the Universe, but may indicate a slightly higher value for the baryon density. We clarify precisely what the two methods determine, and point out that differing values for the baryon density can indicate either an inconsistency or physics beyond the standard models of cosmology and particle physics. We discuss other signatures of the new physics in CMB anisotropy.

  3. Probing lepton asymmetry with 21 cm fluctuations

    SciTech Connect (OSTI)

    Kohri, Kazunori; Oyama, Yoshihiko [The Graduate University for Advanced Studies (Sokendai), 1-1 Oho, Tsukuba 305-0801 (Japan); Sekiguchi, Toyokazu [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 (Japan); Takahashi, Tomo, E-mail: kohri@post.kek.jp, E-mail: oyamayo@post.kek.jp, E-mail: toyokazu.sekiguchi@helsinki.fi, E-mail: tomot@cc.saga-u.ac.jp [Department of Physics, Saga University, Saga 840-8502 (Japan)

    2014-09-01

    We investigate the issue of how accurately we can constrain the lepton number asymmetry ?{sub ?}=?{sub ?}/T{sub ?} in the Universe by using future observations of 21 cm line fluctuations and cosmic microwave background (CMB). We find that combinations of the 21 cm line and the CMB observations can constrain the lepton asymmetry better than big-bang nucleosynthesis (BBN). Additionally, we also discuss constraints on ?{sub ?} in the presence of some extra radiation, and show that the 21 cm line observations can substantially improve the constraints obtained by CMB alone, and allow us to distinguish the effects of the lepton asymmetry from the ones of extra radiation.

  4. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1985-07-29

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and sway from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch.

  5. Microwave fidelity studies by varying antenna coupling

    E-Print Network [OSTI]

    B. Köber; U. Kuhl; H. -J. Stöckmann; T. Gorin; D. V. Savin; T. H. Seligman

    2010-09-16

    The fidelity decay in a microwave billiard is considered, where the coupling to an attached antenna is varied. The resulting quantity, coupling fidelity, is experimentally studied for three different terminators of the varied antenna: a hard wall reflection, an open wall reflection, and a 50 Ohm load, corresponding to a totally open channel. The model description in terms of an effective Hamiltonian with a complex coupling constant is given. Quantitative agreement is found with the theory obtained from a modified VWZ approach [Verbaarschot et al, Phys. Rep. 129, 367 (1985)].

  6. On-Chip Josephson Junction Microwave Switch

    E-Print Network [OSTI]

    O. Naaman; M. O. Abutaleb; C. Kirby; M. Rennie

    2015-12-04

    The authors report on the design and measurement of a reflective single-pole single-throw microwave switch with no internal power dissipation, based on a superconducting circuit containing a single Josephson junction. The data demonstrate the switch operation with 2 GHz instantaneous bandwidth centered at 10 GHz, low insertion loss, and better than 20 dB on/off ratio. The switch's measured performance agrees well with simulations for input powers up to -100 dBm. An extension of the demonstrated circuit to implement a single-pole double-throw switch is shown in simulation.

  7. Paratek Microwave Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland:NPIProtectio Program |View NewParatek Microwave Inc Jump to: navigation, search

  8. ARM - Field Campaign - Microwave Radiometer Profiler Evaluation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design togovCampaignsMASRAD: Pt. Reyes Stratus CloudAtmosphericgovCampaignsMicrowave

  9. Microwave Melting | Y-12 National Security Complex

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetection ofOctober10 Years2,2004Microwave Melting

  10. Mobile system for microwave removal of concrete surfaces

    DOE Patents [OSTI]

    White, Terry L. (Oak Ridge, TN); Bigelow, Timothy S. (Knoxville, TN); Schaich, Charles R. (Lenoir City, TN); Foster, Jr., Don (Knoxville, TN)

    1997-01-01

    A method and apparatus for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface.

  11. Cosmological String Backgrounds from Gauged WZW Models

    E-Print Network [OSTI]

    C. Kounnas; D. Luest

    1992-05-18

    We discuss the four-dimensional target-space interpretation of bosonic strings based on gauged WZW models, in particular of those based on the non-compact coset space $SL(2,{\\bf R})\\times SO(1,1)^2 /SO(1,1)$. We show that these theories lead, apart from the recently broadly discussed black-hole type of backgrounds, to cosmological string backgrounds, such as an expanding Universe. Which of the two cases is realized depends on the sign of the level of the corresponding Kac-Moody algebra. We discuss various aspects of these new cosmological string backgrounds.

  12. Faraday rotation limits on a primordial magnetic field from Wilkinson Microwave Anisotropy Probe five-year data

    SciTech Connect (OSTI)

    Kahniashvili, Tina [Department of Physics and McWilliams Center for Cosmology, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON P3E 2C6 (Canada); National Abastumani Astrophysical Observatory, Ilia Chavchavadze State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Maravin, Yurii [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States); Kosowsky, Arthur [Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, Pennsylvania 15260 (United States)

    2009-07-15

    A primordial magnetic field in the early universe will cause Faraday rotation of the linear polarization of the cosmic microwave background generated via Compton scattering at the surface of last scattering. This rotation induces a nonzero parity-odd (B-mode) polarization component. The Wilkinson Microwave Anisotropy Probe 5-year data puts an upper limit on the magnitude of the B-polarization power spectrum; assuming that the B-polarization signal is totally due to the Faraday rotation effect, the upper limits on the comoving amplitude of a primordial stochastic magnetic field range from 6x10{sup -8} to 2x10{sup -6} G on a comoving length scale of 1 Mpc, depending on the power spectrum of the magnetic field.

  13. Yttrium oxide transparent ceramics by low-temperature microwave sintering

    SciTech Connect (OSTI)

    Luo, Junming, E-mail: ljmniat@126.com [School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063 (China)] [School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063 (China); Zhong, Zhenchen; Xu, Jilin [School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063 (China)] [School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063 (China)

    2012-12-15

    Graphical abstract: The figure shows the SEM photos of the surfaces of the Y{sub 2}O{sub 3} transparent ceramic samples obtained by microwave sintering and vacuum sintering. It is clearly demonstrated that the grain distribution of the vacuum sintering sample is not uniform with the smallest and the largest particle size at about 2 ?m and 15 ?m respectively, while the grain distribution of microwave sintering sample is uniform with the average diameter at about 2–4 ?m (the smallest reported so far) and with no abnormal growth-up or coarsening phenomenon. We have further found out that the smaller the grain size, the higher the mechanical and optical properties. Display Omitted Highlights: ? The microwave sintering temperature of the sample is lower compared with vacuum. ? The microwave sintering time of the sample is shorter compared with vacuum. ? The mechanical properties of the microwave sintering sample is improved greatly. ? The Y{sub 2}O{sub 3} grain of microwave sintering sample is the smallest reported so far. -- Abstract: Yttrium oxide (Y{sub 2}O{sub 3}) transparent ceramics samples have been successfully fabricated by microwave sintering processing at relatively low temperatures. In comparison with the vacuum sintering processing, Y{sub 2}O{sub 3} transparent ceramics can be obtained by microwave sintering at lower sintering temperature and shorter sintering time, and they possess higher transmittances and mechanical properties. The technologies of low-temperature microwave sintering and the relationships of the microstructures and properties of the specified samples have been investigated in detail. We have found out that the low-temperature microwave sintering technique has its obvious advantages over the conventional methods in manufacturing yttrium oxide transparent ceramics.

  14. The South Pole Telescope bolometer array and the measurement of secondary Cosmic Microwave Background anisotropy at small angular scales

    E-Print Network [OSTI]

    Shirokoff, Erik D.

    2011-01-01

    101 Measured NEP for individual detectors in the season 3noise factor. G and NEP vs. T c . . . . . . . . . . . . . .optimized system delivering an NEP which is around T amp /T

  15. Volume 135B, number 4 PHYSICSLETTERS 9 February 1984 ANISOTROPY OF THE MICROWAVE BACKGROUND IN THE INFLATIONARY COSMOLOGY

    E-Print Network [OSTI]

    Abbott, Laurence

    - tions of wave-vector, k, produce variations in the metric and energy momentum tensor given by *1 g00. WISE z CahforniaInstitute of Technology, Pasadena, CA 91125, USA Received 31 October 1983 Using the Harnson-Zel dovich energy-density fluctuation spectrum predicted by the inflationary cosmology, we com

  16. The South Pole Telescope bolometer array and the measurement of secondary Cosmic Microwave Background anisotropy at small angular scales

    E-Print Network [OSTI]

    Shirokoff, Erik D.

    2011-01-01

    iii 2 The South Pole Telescope 2.1 The Telescope . . . . .modifications . . . . II The South Pole Telescope SZ Cameraand exciting as the South Pole Telescope. Fewer still do so

  17. Low background counting techniques at SNOLAB

    SciTech Connect (OSTI)

    Lawson, Ian; Cleveland, Bruce [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)] [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)

    2013-08-08

    Many of the experiments currently searching for dark matter, studying properties of neutrinos or searching for neutrinoless double beta decay require very low levels of radioactive backgrounds both in their own construction materials and in the surrounding environment. These low background levels are required so that the experiments can achieve the required sensitivities for their searches. SNOLAB has several facilities which are used to directly measure these radioactive backgrounds. This proceedings will describe SNOLAB's High Purity Germanium Detectors, one of which has been in continuous use for the past seven years measuring materials for many experiments in operation or under construction at SNOLAB. A description of the characterisation of SNOLAB's new germanium well detector will be presented. In addition, brief descriptions of SNOLAB's alpha-beta and electrostatic counters will be presented and a description of SNOLAB's future low background counting laboratory will be given.

  18. Lighting Choices - White Background | Department of Energy

    Energy Savers [EERE]

    Choices - White Background Image icon All of these lightbulbs-CFLs, LEDs, and energy-saving incandescents-meet the new energy standards that take effect from 2012-2014. More...

  19. ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Maria Cadeddu

    2004-02-19

    Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

  20. A Low-Cost Hands-On Laboratory for an Undergraduate Microwave Course

    E-Print Network [OSTI]

    Hum, Sean Victor

    A Low-Cost Hands-On Laboratory for an Undergraduate Microwave Course S. V.Hum and M. Okoniewski@ieee.org Abstract A low-operating-cost microwave laboratory for undergraduate students is presented, which and measurement of microwave circuits. By training the students in the proper use of modern microwave test

  1. Sensitivity of satellite microwave and infrared observations to soil moisture at a global scale

    E-Print Network [OSTI]

    Aires, Filipe

    Sensitivity of satellite microwave and infrared observations to soil moisture at a global scale observations include passive microwave emissivities, active microwave scatterometer data, and infrared. For example, we show that the passive microwave polarization differences at 19 GHz and above are essentially

  2. Fiber Bragg gratings for microwave photonics Chao Wang and Jianping Yao*

    E-Print Network [OSTI]

    Yao, Jianping

    Fiber Bragg gratings for microwave photonics subsystems Chao Wang and Jianping Yao* Microwave, Ontario K1N 6N5, Canada *jpyao@eecs.uottawa.ca Abstract: Microwave photonics (MWP) is an emerging filed in which photonic technologies are employed to enable and enhance functionalities in microwave systems

  3. ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Maria Cadeddu

    Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

  4. Portable microwave instrument for non-destructive evaluation of structural characteristics

    DOE Patents [OSTI]

    Bible, D.W.; Crutcher, R.I.; Sohns, C.W.; Maddox, S.R.

    1995-01-24

    A portable microwave instrument for evaluating characteristics of a structural member includes a source of microwave energy, a transmitter coupled to the source of microwave energy for transmitting a microwave signal at the structural member, and a receiver positioned on the same side of the structural member as the transmitter and being disposed to receive a microwave signal reflected by the structural member. A phase angle difference is determined between the transmitted microwave signal and the received microwave signal using a signal splitter and a balanced mixer. The difference in phase angle varies in accordance with differences in size, shape and locations of constituent materials within the structural member. 6 figures.

  5. Portable microwave instrument for non-destructive evaluation of structural characteristics

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Crutcher, Richard I. (Knoxville, TN); Sohns, Carl W. (Oak Ridge, TN); Maddox, Stephen R. (Loudon, TN)

    1995-01-01

    A portable microwave instrument for evaluating characteristics of a structural member includes a source of microwave energy, a transmitter coupled to the source of microwave energy for transmitting a microwave signal at the structural member, and a receiver positioned on the same side of the structural member as the transmitter and being disposed to receive a microwave signal reflected by the structural member. A phase angle difference is determined between the transmitted microwave signal and the received microwave signal using a signal splitter and a balanced mixer. The difference in phase angle varies in accordance with differences in size, shape and locations of constituent materials within the structural member.

  6. 3-point temperature anisotropies in WMAP: Limits on CMB non-Gaussianities and non-linearities

    E-Print Network [OSTI]

    E. Gaztanaga; J. Wagg

    2003-06-12

    We present a study of the 3-pt angular correlation function w_3= of (adimensional) temperature anisotropies measured by the Wilkinson Microwave Anisotropy Probe (WMAP). Results can be normalized to the 2-point function w_2 = in terms of the hierarchical: q_3 ~ w_3/w_2^2 or dimensionless: d_3 ~ w_2/w_2^{3/2}$ amplitudes. Strongly non-Gaussian models are generically expected to show d_3 > 1 or q_3 > 10^3 d_3. Unfortunately, this is comparable to the cosmic variance on large angular scales. For Gaussian primordial models, q_3 gives a direct measure of the non-linear corrections to temperature anisotropies in the sky: delta = delta_L + f_{NLT} (delta_L^2 - ) with f_{NLT} = q_3/2 for the leading order term in w_2^2. We find good agreement with the Gaussian hypothesis d_3 ~ 0 within the cosmic variance of LCDM simulations (with or without a low quadrupole). The strongest constraints on q_3 come from scales smaller than 1 degree. We find q_3 =19 +/-141 for (pseudo) collapsed configurations and an average of q_3 = 336 +/-218 for non-collapsed triangles. The corresponding non-linear coupling parameter, f_{NL}, for curvature perturbations Phi, in the Sachs-Wolfe (SW) regime is: f_{NL}^{SW} = q_3/6, while on degree scales, the extra power in acoustic oscillations produces f_{NL} ~ q_3/30 in the LCM model. Errors are dominated by cosmic variance, but for the first time they begin to be small enough to constrain the leading order non-linear effects with coupling of order unity.

  7. The Background Field Approximation in (quantum) cosmology

    E-Print Network [OSTI]

    R. Parentani

    1998-03-12

    We analyze the Hamilton-Jacobi action of gravity and matter in the limit where gravity is treated at the background field approximation. The motivation is to clarify when and how the solutions of the Wheeler-DeWitt equation lead to the Schr\\"odinger equation in a given background. To this end, we determine when and how the total action, solution of the constraint equations of General Relativity, leads to the HJ action for matter in a given background. This is achieved by comparing two neighboring solutions differing slightly in their matter energy content. To first order in the change of the 3-geometries, the change of the gravitational action equals the integral of the matter energy evaluated in the background geometry. Higher order terms are governed by the ``susceptibility'' of the geometry. These classical properties also apply to quantum cosmology since the conditions which legitimize the use of WKB gravitational waves are concomitant with those governing the validity of the background field approximation.

  8. Galvanically split superconducting microwave resonators for introducing internal voltage bias

    SciTech Connect (OSTI)

    Graaf, S. E. de, E-mail: degraaf@chalmers.se; Davidovikj, D.; Adamyan, A.; Kubatkin, S. E.; Danilov, A. V. [Department of Microtechnology and Nanoscience, MC2, Chalmers University of Technology, SE-41296 Gothenburg (Sweden)

    2014-02-03

    We present the design and performance of high-Q superconducting niobium nitride microwave resonators intended for use in hybrid quantum systems, coupling spin degrees of freedom to the cavity mode, both magnetically and electrically. We demonstrate a solution that allows to introduce static electric fields in the resonator without compromising the microwave performance. Quality factors above 10{sup 5} remain unchanged in strong applied static electric fields above 10 MV/m and magnetic fields up to ?400?mT. By design, the configuration of the dc field matches that of the microwave field, especially advantageous for experiments on electrostatically controlled spin systems.

  9. Electrical detection of microwave assisted magnetization reversal by spin pumping

    SciTech Connect (OSTI)

    Rao, Siddharth; Subhra Mukherjee, Sankha; Elyasi, Mehrdad; Singh Bhatia, Charanjit; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering and NUSNNI, National University of Singapore, Singapore 117576 (Singapore)

    2014-03-24

    Microwave assisted magnetization reversal has been investigated in a bilayer system of Pt/ferromagnet by detecting a change in the polarity of the spin pumping signal. The reversal process is studied in two material systems, Pt/CoFeB and Pt/NiFe, for different aspect ratios. The onset of the switching behavior is indicated by a sharp transition in the spin pumping voltage. At a threshold value of the external field, the switching process changes from partial to full reversal with increasing microwave power. The proposed method provides a simple way to detect microwave assisted magnetization reversal.

  10. Electron beam collector for a microwave power tube

    DOE Patents [OSTI]

    Dandl, Raphael A. (Oak Ridge, TN)

    1980-01-01

    This invention relates to a cylindrical, electron beam collector that efficiently couples the microwave energy out of a high power microwave source while stopping the attendant electron beam. The interior end walls of the collector are a pair of facing parabolic mirrors and the microwave energy from an input horn is radiated between the two mirrors and reassembled at the entrance to the output waveguide where the transmitted mode is reconstructed. The mode transmission through the collector of the present invention has an efficiency of at least 94%.

  11. Method and apparatus for component separation using microwave energy

    DOE Patents [OSTI]

    Morrow, Marvin S. (Kingston, TN); Schechter, Donald E. (Ten Mile, TN); Calhoun, Jr., Clyde L. (Knoxville, TN)

    2001-04-03

    A method for separating and recovering components includes the steps of providing at least a first component bonded to a second component by a microwave absorbent adhesive bonding material at a bonding area to form an assembly, the bonding material disposed between the components. Microwave energy is directly and selectively applied to the assembly so that substantially only the bonding material absorbs the microwave energy until the bonding material is at a debonding state. A separation force is applied while the bonding material is at the debonding state to permit disengaging and recovering the components. In addition, an apparatus for practicing the method includes holders for the components.

  12. Microwave Processing of Simulated Advanced Nuclear Fuel Pellets

    SciTech Connect (OSTI)

    D.E. Clark; D.C. Folz

    2010-08-29

    Throughout the three-year project funded by the Department of Energy (DOE) and lead by Virginia Tech (VT), project tasks were modified by consensus to fit the changing needs of the DOE with respect to developing new inert matrix fuel processing techniques. The focus throughout the project was on the use of microwave energy to sinter fully stabilized zirconia pellets using microwave energy and to evaluate the effectiveness of techniques that were developed. Additionally, the research team was to propose fundamental concepts as to processing radioactive fuels based on the effectiveness of the microwave process in sintering the simulated matrix material.

  13. Evidence-Based Background Material Underlying Guidance for Federal...

    Energy Savers [EERE]

    Background Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans Evidence-Based Background Material Underlying Guidance...

  14. Background model for the Majorana Demonstrator

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cuesta, C.; Abgrall, N.; Aguayo, E.; Avignone, F. T.; Oak Ridge National Lab.; Barabash, A. S.; Bertrand, F. E.; Boswell, M.; Brudanin, V.; Busch, M.; et al

    2015-01-01

    The Majorana Collaboration is constructing a system containing 40 kg of HPGe detectors to demonstrate the feasibility and potential of a future tonne-scale experiment capable of probing the neutrino mass scale in the inverted-hierarchy region. To realize this, a major goal of the Majorana Demonstrator is to demonstrate a path forward to achieving a background rate at or below 1 cnt/(ROI-t-y) in the 4 keV region of interest around the Q-value at 2039 keV. This goal is pursued through a combination of a significant reduction of radioactive impurities in construction materials with analytical methods for background rejection, for example usingmore »powerful pulse shape analysis techniques profiting from the p-type point contact HPGe detectors technology. The effectiveness of these methods is assessed using simulations of the different background components whose purity levels are constrained from radioassay measurements.« less

  15. Tidal Forces in Naked Singularity Backgrounds

    E-Print Network [OSTI]

    Goel, Akash; Roy, Pratim; Sarkar, Tapobrata

    2015-01-01

    The end stage of a gravitational collapse process can generically result in a black hole or a naked singularity. Here we undertake a comparative analysis of the nature of tidal forces in these backgrounds. The effect of such forces is generically exemplified by the Roche limit, which predicts the distance within which a celestial object disintegrates due to the tidal effects of a second more massive object. In this paper, using Fermi normal coordinates, we numerically compute the Roche limit for a class of non-rotating naked singularity backgrounds, and compare them with known results for Schwarzschild black holes. Our analysis indicates that there might be substantially large deviations in the magnitudes of tidal forces in naked singularity backgrounds, compared to the black hole cases. If observationally established, these can prove to be an effective indicator of the nature of the singularity at a galactic centre.

  16. Background model for the Majorana Demonstrator

    SciTech Connect (OSTI)

    Cuesta, C. [Univ. of Washington, Seattle, WA (United States); Abgrall, N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Aguayo, E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Avignone, F. T. [Univ. of South Carolina, Columbia, SC (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Barabash, A. S. [Inst. of Theoretical and Experimental Physics (ITEP), Moscow (Russian Federation); Bertrand, F. E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Boswell, M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brudanin, V. [Joint Inst. for Nuclear Research (JINR), Dubna (Russian Federation); Busch, M. [Duke Univ., Durham, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Byram, D. [Univ. of South Dakota, Vermillion, SD (United States); Caldwell, A. S. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Chan, Y -D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Christofferson, C. D. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Combs, D. C. [North Carolina State Univ., Raleigh, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Detwiler, J. A. [Univ. of Washington, Seattle, WA (United States); Doe, P. J. [Univ. of Washington, Seattle, WA (United States); Efremenko, Yu. [Univ. of Tennessee, Knoxville, TN (United States); Egorov, V. [Joint Inst. for Nuclear Research (JINR), Dubna (Russian Federation); Ejiri, H. [Osaka Univ. (Japan). Research Center for Nuclear Physics and Dept. of Physics; Elliott, S. R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fast, J. E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Finnerty, P. [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Fraenkle, F. M. [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Galindo-Uribarri, A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giovanetti, G. K. [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Goett, J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Green, M. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gruszko, J. [Univ. of Washington, Seattle, WA (United States); Guiseppe, V. [Univ. of South Carolina, Columbia, SC (United States); Gusev, K. [Joint Inst. for Nuclear Research (JINR), Dubna (Russian Federation); Hallin, A. [Univ. of Alberta, Edmonton, AB (Canada); Hazama, R. [Osaka Univ. (Japan). Research Center for Nuclear Physics and Dept. of Physics; Hegai, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Henning, R. [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Hoppe, E. W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Howard, S. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Howe, M. A. [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Keeter, K. J. [Black Hills State Univ., Spearfish, SD (United States); Kidd, M. F. [Tennessee Technological Univ., Cookeville, TN (United States); Kochetov, O. [Joint Inst. for Nuclear Research (JINR), Dubna (Russian Federation); Konovalov, S. I. [Inst. of Theoretical and Experimental Physics (ITEP), Moscow (Russian Federation); Kouzes, R. T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); LaFerriere, B. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Leon, J. [Univ. of Washington, Seattle, WA (United States); Leviner, L. E. [North Carolina State Univ., Raleigh, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States); Loach, J. C. [Shanghai Jiao Tong Univ. (China)

    2015-01-01

    The Majorana Collaboration is constructing a system containing 40 kg of HPGe detectors to demonstrate the feasibility and potential of a future tonne-scale experiment capable of probing the neutrino mass scale in the inverted-hierarchy region. To realize this, a major goal of the Majorana Demonstrator is to demonstrate a path forward to achieving a background rate at or below 1 cnt/(ROI-t-y) in the 4 keV region of interest around the Q-value at 2039 keV. This goal is pursued through a combination of a significant reduction of radioactive impurities in construction materials with analytical methods for background rejection, for example using powerful pulse shape analysis techniques profiting from the p-type point contact HPGe detectors technology. The effectiveness of these methods is assessed using simulations of the different background components whose purity levels are constrained from radioassay measurements.

  17. Microwave Instability Simulations for NSLS-II

    SciTech Connect (OSTI)

    Blednykh,A.; Krinsky, S.; Nash, B.; Yu, L.

    2009-05-04

    Potential-well distortion and the microwave instability in the NSLS-II storage ring are investigated. The longitudinal wakepotential is calculated as a sum of the contributions due to vacuum chamber components distributed around the ring. An approximation to the wakepotential for a 0.05-mm charge distribution length, much shorter than the 4.5-mm length of the unperturbed circulating bunch, is used as a pseudo-Green's function for beam dynamics simulations. Comparison of particle tracking simulations using the TRANFT code with the Haissinski solution shows good agreement below the instability threshold current. Above threshold two regimes are observed: (1) energy spread and bunch length are time-dependent (saw tooth behavior); (2) both are time-independent.

  18. Microwave guiding of electrons on a chip

    E-Print Network [OSTI]

    Johannes Hoffrogge; Roman Fröhlich; Mark A. Kasevich; Peter Hommelhoff

    2010-12-10

    Electrons travelling in free space have allowed to explore fundamental physics like the wave nature of matter, the Aharonov-Bohm and the Hanbury Brown-Twiss effect. Complementarily, the precise control over the external degrees of freedom of electrons has proven pivotal for wholly new types of experiments such as high precision measurements of the electron's mass and magnetic moment in Penning traps. Interestingly, the confinement of electrons in the purely electric field of an alternating quadrupole has rarely been considered. Recent advances in the development of planar chip-based ion traps suggest that this technology can be applied to enable entirely new experiments with electron beams guided in versatile potentials. Here we demonstrate the transverse confinement of a low energy electron beam in a linear quadrupole guide based on microstructured planar electrodes and driven at microwave frequencies. A new guided matter-wave system will result, with applications ranging from electron interferometry to novel non-invasive electron microscopy.

  19. 140 GHz pulsed fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, William F. (Oakland, CA); Leskovar, Branko (Moraga, CA)

    1987-01-01

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer (10), including means (11, 19) for generating a high frequency carrier signal, and means (12) for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator (20) and the modulating signal is fed through a pulse switch (23) to the modulator. When the pulse switch (23) is on, the modulator (20) will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device (31) is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device (31) is controlled by the pulse switch (23).

  20. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1987-10-27

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal is disclosed. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch. 5 figs.