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	Sachs-Wolfe effect - Wikipedia, the free encyclopedia
		The Sachs-Wolfe effect is a property of the cosmic background radiation (CBR), in which gravitational bodies redshift the CBR, causing it to appear uneven.
		This effect is the predominant source of fluctuations in the CBR for angular scales above about ten degrees.
		Sachs, Rainer Kurt, and Arthur Michael Wolfe, "Perturbations of a cosmological model and angular variations of the cosmic microwave background", Astrophysical Journal, 1967, 147, 73.
	en.wikipedia.org /wiki/Sachs-Wolfe_effect (224 words)

	Daniel Baumann - Princeton University
		We show that both effects produce equal E- and B-parity polarization, and are, in general, several orders of magnitude below the dominant polarization contributions at the last scattering surface to E-modes or the gravitational-lensing contribution to B-modes at intermediate redshifts.
		These effects are also several orders of magnitude below the B polarization due to lensing even after subtraction with higher-order correlations, and are thus too small to constitute a background for searches for the polarization signature of inflationary gravitational waves.
		We discuss (1) the contributions to the angular power spectrum from the thermal and kinetic SZ effects, (2) the effect of SZ non-Gaussianities on cosmological parameter estimation, and (3) the SZ-induced CMB polarization towards galaxy clusters.
	www.princeton.edu /~dbaumann/publications.htm (960 words)

	The Integrated Sachs-Wolfe effect as a probe of non-standard cosmological evolution (Site not responding. Last check: 2007-10-21)
		The Integrated Sachs-Wolfe effect as a probe of non-standard cosmological evolution
		The Integrated Sachs-Wolfe effect is studied in non-standard cosmologies.
		The effect on the overall normalization of the CMB power spectrum is also discussed as non-standard cosmologies can affect the overall normalization significantly and enhance the primordial fluctuations.
	aanda.u-strasbg.fr:2002 /articles/aa/abs/2004/33/aa1104/aa1104.html (134 words)

	Introduction (Site not responding. Last check: 2007-10-21)
		The integrated Sachs-Wolfe (ISW) effect is a gravitational effect experienced by the cosmic microwave background (CMB) photons as they travel to the observers today from the surface of last scattering (SLS) at recombination.
		However, recent observations of the acceleration of the universe have led to the belief that there is a non-trivial smooth energy component in the universe, the so-called Dark Energy.
		It is to this end that this website is dedicated, with the hope that an understanding of the ISW effect's origin, the possibilities of its detection and the information it conveys about the nature of the dark energy may assist us in better understanding the universe in which we all live.
	kicp.uchicago.edu /~davemilr/ISW/ISW_effect_Home.htm (196 words)

	Integrated Sachs-Wolfe Effect
		The subsequent rise at low l in the CMB power spectrum is known as the Sachs-Wolfe (SW) effect, and since it is imprinted on the CMB power spectrum at the time of last scattering, it is considered a primary anisotropy.
		We use the adjective "integrated" because the net effect on the photon is a sum over passages through many potential wells along the line of sight to the observer.
		Furthermore, because the physics driving these two effects are very similar, the bump in the spectrum caused by early ISW segues rather nicely into the first acoustic peak.
	astro.uchicago.edu /~laroque/ISW.html (1346 words)

	Mellon College of Science - News
		The ISW effect is a measurement of this trade-off between these two and says "dark energy" is winning on the largest scales we can see in the universe.
		This effect is an imprint or shadow of dark energy on microwaves.
		The effect also measures the changes in temperature of cosmic microwave background due to the effects of gravity on the energy of photons, added Scranton.
	www.cmu.edu /mcs/about-mcs/news/030721-dark.html (1360 words)

	wunch @ astro . princeton
		Abstract: The Integrated Sachs-Wolfe (ISW) effect is a direct signature of the presence of dark energy in the universe, in the absence of spatial curvature.
		A powerful method for observing the ISW effect is through cross-correlation of the Cosmic Microwave Background (CMB) with a tracer of the matter in the low redshift universe.
		Then, I will argue that, while an ISW detection will not be a very accurate way of constraining the conventional properties of dark energy, it could be a valuable means of testing alternative theories of gravity on large physical scales.
	www.astro.princeton.edu /~wserber/wunch/niayesh.htm (156 words)

	The Doppler Peak
		Although called the ``Doppler'' peak the Doppler effect is only one of the mechanisms which contribute to it.
		The reason for the peak is that a perturbation entering the horizon starts to grow in density contrast with the over-dense zones collapsing and the under-dense expanding until the tightly coupled photons can resist gravity via radiation pressure and reverse the direction of the oscillation.
		The amplitude of the effect is proportional to
	www.iac.es /galeria/raw/cosmosom/node4.html (260 words)

	Evidence for the Big Bang (Site not responding. Last check: 2007-10-21)
		A similar phenomenon is known from the Doppler effect (mostly known for sound, but equally valid for light): when the emitter of light flies away from the observer, the wavelength of the observed light is longer than the wavelength which the sender emitted (measured in his rest frame).
		Since the source for this effect is the same as for the red shift, the BBT predicts that the factor by which time should appear to be slowed down is exactly equal to one plus the redshift of the object.
		One important consequence of this effect is that thermal emission from a fl body at a given temperature at some point in the history of the universe will still appear as a thermal spectrum later on, but at a temperature that is a factor of (1+z) lower.
	www.rzuser.uni-heidelberg.de /~bfeuerba (19204 words)

	Detection
		Now that we have firmly established the theoretical background and the observational phenomenology of the integrated Sachs-Wolfe effect, it is time to see just what progress has been made towards its detection and what this means for the future experiments.
		Since its suggestion by Crittenden and Turok (1996), several attempts have been made to detect the ISW effect both through the CMB temperature anisotropy power spectrum itself and through its cross-correlation with tracers of the large-scale structure gravitational potentials.
		The ISW effect remains one of the most direct and quantitative measure of the dark energy available to us today, and it is proving its worth.
	cfcp.uchicago.edu /~davemilr/ISW/ISW_detection.htm (594 words)

	Astro-ph for busy people (Site not responding. Last check: 2007-10-21)
		The transition from hadronic matter to quark matter in the core of neutron stars is likely to be associated with the appearance of a mixed phase, leading to a smooth variation of the star density profile.
		We study the hydrodynamical effects of two colliding shells, adopted to model internal shocks in various relativistic outflows such as gamma-ray bursts and blazars.
		By using simple models for the evolution of the cluster mass function and detailed modeling for a variety of observational techniques, we show that the optimum survey yield is achieved when the average size of the clusters selected is close to the size of the telescope beam.
	www.camk.edu.pl /~gwar/astro-ph/2004.10.18.html (6853 words)

	Munch (Site not responding. Last check: 2007-10-21)
		This is consistent with the expected amplitude of the ISW effect, but requires a lower matter density than is usually assumed: the amplitude, parametrized by the galaxy bias assuming \Omega_M=0.3, \Omega_\Lambda=0.7 and \sigma_8=0.9, is b_g = 4.05 \pm 1.54 for V band, with similar results for the other bands.
		It has recently been suggested that Planck scale physics may effect the evolution of cosmological fluctuations in the early stages of cosmological inflation in a non-trivial way, leading to an excited state for modes whose wavelength is super-Planck but sub-Hubble.
		In fact, it has been suggested that such back-reaction effects may lead to tight constraints on the magnitude of possible deviations from the usual predictions of inflation.
	home.fnal.gov /~bertone/DM/JC110104.html (1371 words)

	Integrated Sachs Wolfe effect - Encyclopedia Glossary Meaning Explanation Integrated Sachs Wolfe effect (Site not responding. Last check: 2007-10-21)
		Integrated Sachs Wolfe effect - Encyclopedia Glossary Meaning Explanation Integrated Sachs Wolfe effect.
		The list of the Integrated Sachs Wolfe effect Authors is
		The orginal Integrated Sachs Wolfe effect article can be editet
	www.encyclopedia-glossary.com /en/Integrated-Sachs-Wolfe-effect.html (297 words)

	Astro-ph for busy people (Site not responding. Last check: 2007-10-21)
		The Integrated Sachs-Wolfe (ISW) effect is a direct signature of the presence of dark energy in the universe, in the absence of spatial curvature.
		The latter effect is similar to the redshift space distortion seen in galaxy surveys and this can cause changes of 50% or more in the birghtness temperature fluctuations.
		No temperature dependence or isotope effect was observed for the fast component, whereas the slow component exhibits both the H/D isotope effect (1.1-1.3) and strong temperature dependence (15 to 300 K).
	www.camk.edu.pl /~gwar/astro-ph/2004.01.13.html (10319 words)

	Cosmology -- Large Scale Structure (Site not responding. Last check: 2007-10-21)
		Their results indicate that lensing at moderate redshift can probe the filaments best among these three observational strategies, but also that the SZ effect will be useful for probing the outskirts of clusters.
		Bharadwaj (MRI) and D. Munshi (QMW) has studied the effect of nonlinear corrections to the Sachs-Wolfe relation on the gaussianity of the cosmic microwave background (CMB) temperature fluctuations arising from gaussian initial conditions.
		Previous studies have been limited to the effect of nonlinear gravitational instability of density perturbations.
	www.cita.utoronto.ca /webpages/CITA/annrep96/node29.html (1457 words)

	The Cosmic Mirror # 258
		This effect is an imprint or shadow of dark energy on microwaves and also measures the changes in temperature of cosmic microwave background due to the effects of gravity on the energy of photons.
		Technically speaking, the ISW effect is the integrated differential gravitational redshift caused by the evolution of gravitational potentials along the path traveled by the photons.
		A unique aspect of the SDSS data is its ability to accurately measure the distances to all galaxies from photographic analysis of their photometric redshifts: Therefore one can watch the imprint of this effect on the CMB grow as a function of the age of the universe.
	www.astro.uni-bonn.de /~dfischer/mirror/258.html (1971 words)

	[No title] (Site not responding. Last check: 2007-10-21)
		In some scenarios, the peculiar gravitational potential of linear and mildly nonlinear structures depends on time and, as a result of this dependence, a late integrated Sachs-Wolfe effect appears.
		Here, an appropriate formalism is used which allows us to improve on the analysis of the spatial scales and locations of the main cosmological inhomogeneities producing this effect.
		The study is performed in the framework of the currently preferred flat model with cosmological constant, and it is also developed in an open model for comparisons.
	www.elsevier.com /cdweb/journals/13841076/articles/5/2/S138410760000016.abstract.en (106 words)

	COLLECTED ABSTRACTS (Site not responding. Last check: 2007-10-21)
		One of the principal advangtages of the SDSS sample over previous samples is that the galaxies in it lie in environments ranging from isolation in the field to the dense cores of clusters.
		Magnitude and redshift limited samples show that radio galaxies have a different optical luminosity distribution than non-radio galaxies selected by the same criteria; when galaxies are further separated by their colors, this result remains valid for both blue and red galaxies.
		The distributions of radio-to-optical flux ratio are similar for blue and red galaxies in redshift-limited samples; this similarity implies that the difference in their luminosity functions, and resulting selection effects, are the dominant cause for the preponderance of red radio galaxies in flux-limited samples.
	www.strw.leidenuniv.nl /~overzier/science/surveys/sdss.html (6791 words)

	Astrophysics authors/titles "new"
		The presence of an inner (secondary) bar in the galaxy images is shown to have no effect on the circumnuclear kinematics of the gas and stars.
		For possible detection of these relatively small (compared to pressure effects) fields by helioseismic methods it is important to know the range of the field strengths and their distribution.
		With the diagram, it is found that four conversions occur in supernova, two are induced by the RSF effect and two by the pure MSW.
	www.tat.physik.uni-tuebingen.de /~weth/astro-ph/astro-ph_021107.html (6935 words)

	6.4 Curvature perturbations and the Sachs-Wolfe effect
		The KK effects on the brane contribute a non-adiabatic mode, although
		The brane-world corrections to the general relativistic Sachs-Wolfe effect are then given by [191]
		on large scales is discussed in [19], and the Sachs-Wolfe effect is estimated as
	www.emis.de /journals/LRG/Articles/lrr-2004-7/articlesu21.html (390 words)

	Small Scale Integrated Sachs-Wolfe Effect (Site not responding. Last check: 2007-10-21)
		The integrated Sachs-Wolfe (ISW) effect can be an important factor in the generation of cosmic microwave background anisotropies on all scales, especially in a reionized curvature- or Lambda -dominated universe.
		We present a simple analytic treatment of the ISW effect, which is analogous to thick last scattering surface techniques for the Doppler effect, that compares quite well with the full numerical calculations.
		The power spectrum of temperature fluctuations due to the small scale ISW effect has a wave number dependence k^-5 times that of the matter power spectrum.
	astro.uchicago.edu /~laroque/abstracts/hu_sugiyama_abs.html (97 words)

	[No title] (Site not responding. Last check: 2007-10-21)
		The integrated Sachs-Wolfe (ISW) effect is a secondary CMB signal normally buried beneath the primary one.
		Its dependence on the evolution of the gravitational potential makes it a tantalizing candidate for a different way of seeing the effects of dark energy.
		One technique for extracting more information from the ISW effect is to look for correlations between CMB maps and other observations dependent on structure along the line of sight.
	stokstad.lbl.gov /INPA/Abstracts/052804.html (97 words)

	Joint UVA/NRAO Colloquium (Site not responding. Last check: 2007-10-21)
		Current interpretations of supernova light curves and the acoustic peaks in the power spectrum of fluctuations in the cosmic microwave background (CMB) suggest that the universe is accelerating rather than decelerating.
		If this is the case, then additional fluctuations are generated as CMB photons traverse collapsing structures (the integrated Sachs-Wolfe effect).
		A comparison of the CMB with tracers of mass on scales of hundreds of kpc provides an important test of this effect and allows a constraint to be placed on the value of the cosmological constant.
	www.astro.virginia.edu /events/event.php?eventID=29 (120 words)

	ABC Online Forum (Site not responding. Last check: 2007-10-21)
		I followed the links and looked at the paper that was behind the news story in Nature.
		The paper mentioned the Integrated Sachs-Wolfe effect and how it caused the energy shift in the photons that they observed.
		They didn't elaborate much on what it did and I'm not familiar with the journal names they used the abbreviations of in their references.
	www2b.abc.net.au /science/k2/stn/archives/archive56/newposts/610/topic610968.shtm (126 words)

	Drexel University: Department of Physics: Colloquium on Searching for the Integrated Sachs-Wolfe Effect: More Evidence ...
		Searching for the Integrated Sachs-Wolfe Effect: More Evidence for a Cosmological Constant
		Recent observations of supernovae and of the cosmic microwave background (CMB) indicate that the universe may have a substantial Cosmological Constant and, therefore, exhibit accelerated expansion.
		I will discuss our recent attempts to search for correlations of the X-ray background as well as NVSS radio sources with the WMAP satellite CMB map and discuss the implications regarding a cosmological constant.
	einstein.drexel.edu /colloquia/abstracts/042403.html (140 words)

	At Haverford - Academic Update
		Stephen Boughn, the John Farnum Professor of Astronomy, received a two-year $55,000 grant from NASA for research entitled "Investigations of Large-Scale Structure in the X-ray Background and Limits on Cosmological Parameters from the Integrated Sachs-Wolfe Effect." Boughn was also reappointed for another three-year term as divisional associate editor of Physical Review Letters.
		Julio de Paula, associate professor of chemistry, was appointed by the president of the International Union of Pure and Applied Chemistry to the organization's Education Strategy Development Committee (ESDC).
		Finally, in June 2000 Williams will give a one-person exhibition at the Chester Springs Studio of photographs of sites on the Underground Railroad in Chester County, a commission funded by the Pew Exhibtion Initiative Grants.
	www.haverford.edu /publications/spring00/academic.htm (766 words)

	Pitt Chronicle: Science: Dark Energy’s Shadow—Sloan Digital Sky Survey detects physical evidence for dark ... (Site not responding. Last check: 2007-10-21)
		The effect also measures the changes in temperature of cosmic microwave background owing to the effects of gravity on the energy of photons, added Scranton.
		The discovery is “a physical detection of dark energy and highly complementary to other detections of dark energy,” added Bob Nichol, an SDSS collaborator and associate professor of physics at Carnegie Mellon University.
		“Therefore, we can watch the imprint of this effect on the CMB grow as a function of the age of the universe,”; Connolly said.
	www.discover.pitt.edu /media/pcc030908/sci1_dark_energy.html (731 words)

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