Physics of the Cosmic Microwave Background Anisotropy∗
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First Year Wilkinson Microwave Anisotropy Probe (WMAP ) Observations: Determination of Cosmological Parameters
Accepted by the Astrophysical Journal First Year Wilkinson Microwave Anisotropy Probe (WMAP ) Observations: Determination of Cosmological Parameters D. N. Spergel 2, L. Verde 2 3, H. V. Peiris 2, E. Komatsu 2, M. R. Nolta 4, C. L. Bennett 5, M. Halpern 6, G. Hinshaw 5, N. Jarosik 4, A. Kogut 5, M. Limon 5 7, S. S. Meyer 8, L. Page 4, G. S. Tucker 5 7 9, J. L. Weiland 10, E. Wollack 5, & E. L. Wright 11 [email protected] ABSTRACT WMAP precision data enables accurate testing of cosmological models. We find that the emerging standard model of cosmology, a flat ¡ −dominated universe seeded by a nearly scale-invariant adiabatic Gaussian fluctuations, fits the WMAP data. For the WMAP data 2 2 £ ¢ ¤ ¢ £ ¢ ¤ ¢ £ ¢ only, the best fit parameters are h = 0 ¢ 72 0 05, bh = 0 024 0 001, mh = 0 14 0 02, ¥ +0 ¦ 076 ¢ £ ¢ § ¢ £ ¢ = 0 ¢ 166− , n = 0 99 0 04, and = 0 9 0 1. With parameters fixed only by WMAP 0 ¦ 071 s 8 data, we can fit finer scale CMB measurements and measurements of large scale structure (galaxy surveys and the Lyman ¨ forest). This simple model is also consistent with a host of other astronomical measurements: its inferred age of the universe is consistent with stel- lar ages, the baryon/photon ratio is consistent with measurements of the [D]/[H] ratio, and the inferred Hubble constant is consistent with local observations of the expansion rate. We then fit the model parameters to a combination of WMAP data with other finer scale CMB experi- ments (ACBAR and CBI), 2dFGRS measurements and Lyman ¨ forest data to find the model’s 1WMAP is the result of a partnership between Princeton University and NASA's Goddard Space Flight Center. -
Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole
UC Berkeley UC Berkeley Electronic Theses and Dissertations Title Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole Permalink https://escholarship.org/uc/item/6b98h32b Author Takahashi, Yuki David Publication Date 2010 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California Measurement of the Cosmic Microwave Background Polarization with the Bicep Telescope at the South Pole by Yuki David Takahashi A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Physics in the Graduate Division of the University of California, Berkeley Committee in charge: Professor William L. Holzapfel, Chair Professor Adrian T. Lee Professor Chung-Pei Ma Fall 2010 Measurement of the Cosmic Microwave Background Polarization with the Bicep Telescope at the South Pole Copyright 2010 by Yuki David Takahashi 1 Abstract Measurement of the Cosmic Microwave Background Polarization with the Bicep Telescope at the South Pole by Yuki David Takahashi Doctor of Philosophy in Physics University of California, Berkeley Professor William L. Holzapfel, Chair The question of how exactly the universe began is the motivation for this work. Based on the discoveries of the cosmic expansion and of the cosmic microwave background (CMB) ra- diation, humans have learned of the Big Bang origin of the universe. However, what exactly happened in the first moments of the Big Bang? A scenario of initial exponential expansion called “inflation” was proposed in the 1980s, explaining several important mysteries about the universe. Inflation would have generated gravitational waves that would have left a unique imprint in the polarization of the CMB. -
2.1.5 Stress-Strain Relation for Anisotropic Materials
,/... + -:\ 2.1.5Stress-strain Relation for AnisotropicMaterials The generalizedHook's law relatingthe stressesto strainscan be writtenin the form U2, 13,30-32]: o,=C,,€, (i,i =1,2,.........,6) Where: o, - Stress('ompttnents C,, - Elasticity matrix e,-Straincomponents The material properties (elasticity matrix, Cr) has thirty-six constants,stress-strain relations in the materialcoordinates are: [30] O1 LI CT6 a, l O2 03_ a, -t ....(2-6) T23 1/ )1 T32 1/1l 'Vt) Tt2 C16 c66 I The relations in equation (3-6) are referred to as characterizing anisotropicmaterials since there are no planes of symmetry for the materialproperties. An alternativename for suchanisotropic material is a triclinic material. If there is one plane of material property symmetry,the stress- strainrelations reduce to: -'+1-/ ) o1 c| ct2 ct3 0 0 crc €l o2 c12 c22 c23 0 0 c26 a: ct3 C23 ci3 0 0 c36 o-\ o3 ....(2-7) 723 000cqqc450 y)1 T3l 000c4sc5s0 Y3l T1a ct6 c26 c36 0 0 c66 1/t) Where the plane of symmetryis z:0. Such a material is termed monoclinicwhich containstfirfen independentelastic constants. If there are two brthogonalplanes of material property symmetry for a material,symmetry will existrelative to a third mutuallyorthogonal plane. The stress-strainrelations in coordinatesaligned with principal material directionswhich are parallel to the intersectionsof the three orthogonalplanes of materialsymmetry, are'. Ol ctl ct2ctl000 tl O2 Ct2 c22c23000 a./ o3 ct3 c23c33000 * o-\ ....(2-8) T23 0 00c4400 y)1 yll 731 0 000css0 712 0 0000cr'e 1/1) 'lt"' -' , :t i' ,/ Suchmaterial is calledorthotropic material.,There is no interaction betweennormal StreSSeS ot r 02, 03) andanisotropic materials. -
Analysis and Measurement of Horn Antennas for CMB Experiments
Analysis and Measurement of Horn Antennas for CMB Experiments Ian Mc Auley (M.Sc. B.Sc.) A thesis submitted for the Degree of Doctor of Philosophy Maynooth University Department of Experimental Physics, Maynooth University, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland. October 2015 Head of Department Professor J.A. Murphy Research Supervisor Professor J.A. Murphy Abstract In this thesis the author's work on the computational modelling and the experimental measurement of millimetre and sub-millimetre wave horn antennas for Cosmic Microwave Background (CMB) experiments is presented. This computational work particularly concerns the analysis of the multimode channels of the High Frequency Instrument (HFI) of the European Space Agency (ESA) Planck satellite using mode matching techniques to model their farfield beam patterns. To undertake this analysis the existing in-house software was upgraded to address issues associated with the stability of the simulations and to introduce additional functionality through the application of Single Value Decomposition in order to recover the true hybrid eigenfields for complex corrugated waveguide and horn structures. The farfield beam patterns of the two highest frequency channels of HFI (857 GHz and 545 GHz) were computed at a large number of spot frequencies across their operational bands in order to extract the broadband beams. The attributes of the multimode nature of these channels are discussed including the number of propagating modes as a function of frequency. A detailed analysis of the possible effects of manufacturing tolerances of the long corrugated triple horn structures on the farfield beam patterns of the 857 GHz horn antennas is described in the context of the higher than expected sidelobe levels detected in some of the 857 GHz channels during flight. -
La Radiación Del Fondo Cósmico De Microondas Abstracts
Simposio Internacional: La radiación del Fondo Cósmico de Microondas: mensajera de los orígenes del universo International Symposium: CMB Radiation: Messenger of the Origins of Our Universe Madrid, 6 de noviembre de 2014 Madrid, November 6, 2014 I The seeds of structure: A view of the Cosmic Microwave Background, Joseph Silk The shape of the universe as seen by Planck, Enrique Martínez-González Deciphering the beginnings of the universe with CMB polarization, Matías Zaldarriaga 30 years of Cosmic Microwave Background experiments in Tenerife: From temperature to polarization maps, Rafael Rebolo Cosmology from Planck: Do we need a new Physics?, Nazzareno Mandolesi FUNDACIÓN RAMÓN ARECES Simposio Internacional: La radiación del Fondo Cósmico de Microondas: mensajera de los orígenes del universo International Symposium: CMB Radiation: Messenger of the Origins of Our Universe Madrid, 6 de noviembre de 2014 Madrid, November 6, 2014 The seeds of structure: A view of the Cosmic Microwave Background, Joseph Silk One of our greatest challenges is understanding the origin of the structure of the universe.I will describe how the fossil radiation from the beginning of the universe, the cosmic microwave background, has provided a window for probing the initial conditions from which structure evolved. Infinitesimal variations in temperature on the sky, first discovered in 1992, provide the fossil fluctuations that seeded the formation of the galaxies. The cosmic microwave background radiation has now been mapped with ground-based, balloon-borne and satellite telescopes. These provide the basis for our current ``precision cosmology'' in which the universe not only contains Dark Matter but also ``DarkEnergy'', which has accelerated its expansion exponentially in the last 4 billion years. -
Abstract Observation Overview Nustar HXR Imaging Microflare
Imaging and Spectroscopy of Six NuSTAR MicroFlares SH11D-2898 Contact: J. Duncan1, L. Glesener1, I. Hannah2, D. Smith3, B. Grefenstette4 (1Univ, of Minnesota; 2Univ. of Glasgow; 3UC Santa Cruz; 4California Institute of Technology) [email protected] Abstract MicroFlare Time Evolution Hard X-ray (HXR) emission in solar flares originates from regions of high temperature plasma, as well as from non-thermal particle populations [1]. Both of these sources of HXR radiation make solar observation in this band important for study of • NuSTAR observed 6 MicroFlares during this observation. Time evolution is shown in both raw and normalized NuSTAR flare energetics. NuSTAR is the first HXR telescope with direct focusing optics, giving it a dramatic increase in sensitivity countsLivetime acrosscorrection several applied energy ranges for each flare. Counts are livetime-corrected (NuSTAR livetime ranged from 1-14%). Livetime correction applied over previous indirect imaging methods. Here we present NuSTAR observation of six microflares from one solar active Livetime correction applied 5 5 6 5×10 4×10 2.0 10 5 × 4×10 5 region during a period of several hours on May 29th, 2018. In conjunction with simultaneous data from SDO/AIA, data 3×10 5 2-4 keV 2-4 keV 6 3×10 1.5 10 Orbit1, Flare B 4-6 keV 2×105 4-6 keV × 5 counts 2 10 2-4 keV × Orbit1, Flare A 6-8 keV counts Orbit1, Flare C 6-8 keV from this observation has been used to create flare-time images showing the spatial extent of HXR emission. Additionally, 5 5 1 10 1×10 8-10 keV × 8-10 keV 6 4-6 keV 1.0×10 (Left) Estimated GOES A5 flare, with 0 0 1.2 1.2 16:07 16:08 16:09 16:10 16:11 16:46 16:48 16:50 16:52 16:54 NuSTAR lightcurves show time evolution in four different HXR energy ranges over the course of each flare. -
Build a Spacecraft Activity
UAMN Virtual Family Day: Amazing Earth Build a Spacecraft SMAP satellite. Image: NASA. Discover how scientists study Earth from above! Scientists use satellites and spacecraft to study the Earth from outer space. They take pictures of Earth's surface and measure cloud cover, sea levels, glacier movements, and more. Materials Needed: Paper, pencil, craft materials (small recycled boxes, cardboard pieces, paperclips, toothpicks, popsicle sticks, straws, cotton balls, yarn, etc. You can use whatever supplies you have!), fastening materials (glue, tape, rubber bands, string, etc.) Instructions: Step 1: Decide what you want your spacecraft to study. Will it take pictures of clouds? Track forest fires? Measure rainfall? Be creative! Step 2: Design your spacecraft. Draw a picture of what your spacecraft will look like. It will need these parts: Container: To hold everything together. Power Source: To create electricity; solar panels, batteries, etc. Scientific Instruments: This is the why you launched your satellite in the first place! Instruments could include cameras, particle collectors, or magnometers. Communication Device: To relay information back to Earth. Image: NASA SpacePlace. Orientation Finder: A sun or star tracker to show where the spacecraft is pointed. Step 3: Build your spacecraft! Use any craft materials you have available. Let your imagination go wild. Step 4: Your spacecraft will need to survive launching into orbit. Test your spacecraft by gently shaking or spinning it. How well did it hold together? Adjust your design and try again! Model spacecraft examples. Courtesy NASA SpacePlace. Activity adapted from NASA SpacePlace: spaceplace.nasa.gov/build-a-spacecraft/en/ UAMN Virtual Early Explorers: Amazing Earth Studying Earth From Above NASA is best known for exploring outer space, but it also conducts many missions to investigate Earth from above. -
Integrated Sachs Wolfe Effect and Rees Sciama Effect
Prog. Theor. Exp. Phys. 2012, 00000 (24 pages) DOI: 10.1093/ptep/0000000000 Integrated Sachs Wolfe Effect and Rees Sciama Effect Atsushi J. Nishizawa1 1 Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), The University of Tokyo, Chiba 277-8582, Japan ∗E-mail: [email protected] ............................................................................... It has been around fifty years since R. K. Sachs and A. M. Wolfe predicted the existence of anisotropy in the Cosmic Microwave Background (CMB) and ten years since the integrated Sachs Wolfe effect (ISW) was first detected observationally. The ISW effect provides us with a unique probe of the accelerating expansion of the Universe. The cross-correlation between the large-scale structure and CMB has been the most promising way to extract the ISW effect from the data. In this article, we review the physics of the ISW effect and summarize recent observational results and interpretations. ................................................................................................. Subject Index Cosmological perturbation theory, Cosmic background radiations, Dark energy and dark matter 1. Overview After the discovery of the isotropic radiation of the Cosmic Microwave Background (CMB) of the Universe by A. A. Penzias and R. W. Wilson in 1965 [100], R. K. Sachs and A. M Wolfe predict the existence of anisotropy in the CMB associated with the gravitational redshift in 1967 [116]. They fully integrate the geodesic equation in a perturbed Friedman-Robertson-Walker (FRW) metric in the fully general relativistic framework. The Sachs-Wolfe (SW) is the first paper that predicts the presence of the anisotropy in the CMB which now plays an important role for constraining cosmo- logical models, the nature of dark energy, modified gravity, and non-Gaussianity of the primordial fluctuation. -
FIRST-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) 1 OBSERVATIONS: DETERMINATION of COSMOLOGICAL PARAMETERS D. N. Spergel,2
The Astrophysical Journal Supplement Series, 148:175–194, 2003 September E # 2003. The American Astronomical Society. All rights reserved. Printed in U.S.A. FIRST-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP)1 OBSERVATIONS: DETERMINATION OF COSMOLOGICAL PARAMETERS D. N. Spergel,2 L. Verde,2,3 H. V. Peiris,2 E. Komatsu,2 M. R. Nolta,4 C. L. Bennett,5 M. Halpern,6 G. Hinshaw,5 N. Jarosik,4 A. Kogut,5 M. Limon,5,7 S. S. Meyer,8 L. Page,4 G. S. Tucker,5,7,9 J. L. Weiland,10 E. Wollack,5 and E. L. Wright11 Received 2003 February 11; accepted 2003 May 20 ABSTRACT WMAP precision data enable accurate testing of cosmological models. We find that the emerging standard model of cosmology, a flat Ã-dominated universe seeded by a nearly scale-invariant adiabatic Gaussian fluctuations, fits the WMAP data. For the WMAP data only, the best-fit parameters are h ¼ 0:72 Æ 0:05, 2 2 þ0:076 bh ¼ 0:024 Æ 0:001, mh ¼ 0:14 Æ 0:02, ¼ 0:166À0:071, ns ¼ 0:99 Æ 0:04, and 8 ¼ 0:9 Æ 0:1. With parameters fixed only by WMAP data, we can fit finer scale cosmic microwave background (CMB) measure- ments and measurements of large-scale structure (galaxy surveys and the Ly forest). This simple model is also consistent with a host of other astronomical measurements: its inferred age of the universe is consistent with stellar ages, the baryon/photon ratio is consistent with measurements of the [D/H] ratio, and the inferred Hubble constant is consistent with local observations of the expansion rate. -
The Reionization of Cosmic Hydrogen by the First Galaxies Abstract 1
David Goodstein’s Cosmology Book The Reionization of Cosmic Hydrogen by the First Galaxies Abraham Loeb Department of Astronomy, Harvard University, 60 Garden St., Cambridge MA, 02138 Abstract Cosmology is by now a mature experimental science. We are privileged to live at a time when the story of genesis (how the Universe started and developed) can be critically explored by direct observations. Looking deep into the Universe through powerful telescopes, we can see images of the Universe when it was younger because of the finite time it takes light to travel to us from distant sources. Existing data sets include an image of the Universe when it was 0.4 million years old (in the form of the cosmic microwave background), as well as images of individual galaxies when the Universe was older than a billion years. But there is a serious challenge: in between these two epochs was a period when the Universe was dark, stars had not yet formed, and the cosmic microwave background no longer traced the distribution of matter. And this is precisely the most interesting period, when the primordial soup evolved into the rich zoo of objects we now see. The observers are moving ahead along several fronts. The first involves the construction of large infrared telescopes on the ground and in space, that will provide us with new photos of the first galaxies. Current plans include ground-based telescopes which are 24-42 meter in diameter, and NASA’s successor to the Hubble Space Telescope, called the James Webb Space Telescope. In addition, several observational groups around the globe are constructing radio arrays that will be capable of mapping the three-dimensional distribution of cosmic hydrogen in the infant Universe. -
CMBEASY:: an Object Oriented Code for the Cosmic Microwave
www.cmbeasy.org CMBEASY:: an Object Oriented Code for the Cosmic Microwave Background Michael Doran∗ Department of Physics & Astronomy, HB 6127 Wilder Laboratory, Dartmouth College, Hanover, NH 03755, USA and Institut f¨ur Theoretische Physik der Universit¨at Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany We have ported the cmbfast package to the C++ programming language to produce cmbeasy, an object oriented code for the cosmic microwave background. The code is available at www.cmbeasy.org. We sketch the design of the new code, emphasizing the benefits of object orienta- tion in cosmology, which allow for simple substitution of different cosmological models and gauges. Both gauge invariant perturbations and quintessence support has been added to the code. For ease of use, as well as for instruction, a graphical user interface is available. I. INTRODUCTION energy, dark matter, baryons and neutrinos. The dark energy can be a cosmological constant or quintessence. The cmbfast computer program for calculating cos- There are three scalar field field models implemented, or mic microwave background (CMB) temperature and po- alternatively one may specify an equation-of-state his- larization anisotropy spectra, implementing the fast line- tory. Furthermore, the modular code is easily adapted of-sight integration method, has been publicly available to new problems in cosmology. since 1996 [1]. It has been widely used to calculate spec- In the next section IIA we explain object oriented pro- cm- tra for open, closed, and flat cosmological models con- gramming and its use in cosmology. The design of beasy taining baryons and photons, cold dark matter, massless is presented in section II B, while the graphical and massive neutrinos, and a cosmological constant. -
On Gravitational Energy in Newtonian Theories
On Gravitational Energy in Newtonian Theories Neil Dewar Munich Center for Mathematical Philosophy LMU Munich, Germany James Owen Weatherall Department of Logic and Philosophy of Science University of California, Irvine, USA Abstract There are well-known problems associated with the idea of (local) gravitational energy in general relativity. We offer a new perspective on those problems by comparison with Newto- nian gravitation, and particularly geometrized Newtonian gravitation (i.e., Newton-Cartan theory). We show that there is a natural candidate for the energy density of a Newtonian gravitational field. But we observe that this quantity is gauge dependent, and that it cannot be defined in the geometrized (gauge-free) theory without introducing further structure. We then address a potential response by showing that there is an analogue to the Weyl tensor in geometrized Newtonian gravitation. 1. Introduction There is a strong and natural sense in which, in general relativity, there are metrical de- grees of freedom|including purely gravitational, i.e., source-free degrees of freedom, such as gravitational waves|that can influence the behavior of other physical systems. And yet, if one attempts to associate a notion of local energy density with these metrical degrees of freedom, one quickly encounters (well-known) problems.1 For instance, consider the following simple argument that there cannot be a smooth ten- Email address: [email protected] (James Owen Weatherall) 1See, for instance, Misner et al. (1973, pp. 466-468), for a classic argument that there cannot be a local notion of energy associated with gravitation in general relativity; see also Choquet-Brouhat (1983), Goldberg (1980), and Curiel (2017) for other arguments and discussion.