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[en] We make a more general determination of the inflationary observables in the standard four-dimensional (4D) and five-dimensional (5D) single-field inflationary scenarios by the exact reconstruction of the dynamics of the inflation potential during the observable inflation with a minimal number of assumptions: the computation does not assume the slow-roll approximation and is valid in all regimes if the field is monotonically rolling down its potential. We address higher order effects in the standard and braneworld single-field inflation scenarios by fitting the Hubbble expansion rate and subsequently the inflationary potential directly to WMAP5+SN+BAO and Planck-like simulated data sets. Making use of the Hamilton-Jacobi formalism developed for the 5D single-field inflation model, we compute the scale dependence of the amplitudes of the scalar and tensor perturbations by integrating the exact mode equation. The solutions in 4D and 5D inflation scenarios differ through the dynamics of the background scalar field and the number of e-folds assumed to be compatible with the observational window of inflation. We analyze the implications of the theoretical uncertainty in the determination of the reheating temperature after inflation on the observable predictions of inflation and evaluate its impact on the degeneracy of the standard inflation consistency relation. We find that the detection of tensor perturbations and the theoretical uncertainties in the inflationary observable represents a significant challenge for the future Planck cosmic microwave background measurements: distinguishing between the observational signatures of the standard and braneworld single-field inflation scenarios. This work has been done in the frame of Planck Core Team activities.
[en] Recently, Warm (keV scale) Dark Matter emerged impressively over CDM (Cold Dark Matter) as the leading Dark Matter candidate. In the context of this new Dark Matter situation, which implies novelties in the astrophysical, cosmological and keV particle physics context, this 16. Paris Colloquium 2012 is devoted to the LambdaWDM Standard Model of the Universe. The topics of the colloquium are as follows: -) observational and theoretical progress on the nature of dark matter: keV scale warm dark matter, -) large and small scale structure formation in agreement with observations at large scales and small galactic scales, and -) neutrinos in astrophysics and cosmology. This document gathers the slides of the presentations.
[en] Anisotropy and polarization of the CMB are probing cosmological models with unprecedented precision. The WMAP satellite data are largely consistent with concordance ACDM cosmology. However, intriguing flukes are known to exist that may pinpoint at physics beyond the standard model. Constraining the violations of discrete symmetries in the CMB pattern is a promising mean to investigate these discrepancies. In this paper we constrain the Parity and CVT symmetries through CMB datasets. We describe the basic formalism, the relevant estimators and the overall analysis strategy. We provide marginal evidence for large scale Parity anomaly in the WMAP data that may be soon confirmed or discarded by the Planck satellite. Planck is currently measuring CMB anisotropies and their polarization with a level of precision that will remain unparalleled for many years to come. We also show how the CMB can be used to constrain fundamental symmetry violations in the photon sector through the so-called cosmological birefringence phenomenon. Finally, we provide forecasts for Planck and we discuss how emission from a specific diffuse foreground component arising within the Solar System needs to be kept under strict control to avoid incurring into false positive detections.
[en] We investigate the role of a HDM component in the form of the three massive neutrino flavors for the reionization history of the Universe. Assuming a flat background cosmology described by the best fit power low ΛCDM model with WMAP data (Ωbh2=0.024, Ωmh2=0.14, h=0.72), we analyze the role of the neutrino mass for the properties of the gas in the intergalactic medium (IGM), showing that the temporal evolution of the hydrogen and helium ionization fractions are sensitive to the neutrino mass, with important implications for the CMB anisotropy and polarization angular power spectra
[en] 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 , 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 2σ interval, is in agreement with the corresponding amplitudes, discussed in 
[en] To asses stability against 1/f noise, the Low Frequency Instrument (LFI) on-board the Planck mission will acquire data at a rate much higher than the data rate allowed by the science telemetry bandwith of 35.5 Kbps. The data are processed by an on-board pipeline, followed on-ground by a decoding and reconstruction step, to reduce the volume of data to a level compatible with the bandwidth while minimizing the loss of information. This paper illustrates the on-board processing of the scientific data used by Planck/LFI to fit the allowed data-rate, an intrinsecally lossy process which distorts the signal in a manner which depends on a set of five free parameters (Naver, r1, r2, q, O) for each of the 44 LFI detectors. The paper quantifies the level of distortion introduced by the on-board processing as a function of these parameters. It describes the method of tuning the on-board processing chain to cope with the limited bandwidth while keeping to a minimum the signal distortion. Tuning is sensitive to the statistics of the signal and has to be constantly adapted during flight. The tuning procedure is based on a optimization algorithm applied to unprocessed and uncompressed raw data provided either by simulations, pre-launch tests or data taken in flight from LFI operating in a special diagnostic acquisition mode. All the needed optimization steps are performed by an automated tool, OCA2, which simulates the on-board processing, explores the space of possible combinations of parameters, and produces a set of statistical indicators, among them: the compression rate Cr and the processing noise εQ. For Planck/LFI it is required that Cr = 2.4 while, as for other systematics, εQ would have to be less than 10% of rms of the instrumental white noise. An analytical model is developed that is able to extract most of the relevant information on the processing errors and the compression rate as a function of the signal statistics and the processing parameters to be tuned. This model will be of interest for the instrument data analysis to asses the level of signal distortion introduced in the data by the on-board processing. The method was applied during ground tests when the instrument was operating in conditions representative of flight. Optimized parameters were obtained and inserted in the on-board processor and the performance has been verified against the requirements with the result that the required data rate of 35.5 Kbps has been achieved while keeping the processing error at a level of 3.8% of the instrumental white noise and well below the target 10% level.
[en] The Planck satellite, successfully launched on 2009 May 14 to measure with unprecedented accuracy the primary cosmic microwave background (CMB) anisotropies, is operating as expected. The Standard Model of the Universe ('concordance' model) provides the current realistic context to analyze the CMB and other cosmological/astrophysical data, inflation in the early universe being part of it. The Planck performance for the crucial primordial parameter r, the tensor-to-scalar ratio related to primordial B-mode polarization, will depend on the quality of data analysis and interpretation. The Ginzburg-Landau (G-L) approach to inflation allows us to take high benefit of the CMB data. The fourth-degree double-well inflaton potential gives an excellent fit to the current CMB+LSS data. We evaluate the Planck precision to the recovery of cosmological parameters, taking into account a reasonable toy model for residuals of systematic effects of instrumental and astrophysical origin based on publicly available information. We use and test two relevant models: the ΛCDMr model, i.e., the standard ΛCDM model augmented by r, and the ΛCDMrT model, where the scalar spectral index, ns , and r are related through the theoretical 'banana-shaped' curve r = r(ns ) coming from the G-L theory with a double-well inflaton potential. In the latter case, the analytical expressions for ns and r are imposed as a hard constraint in a Monte Carlo Markov Chain (MCMC) data analysis. We consider two Cl-likelihoods (with and without B modes) and take into account the white noise sensitivity of Planck (LFI and HFI) in the 70, 100, and 143 GHz channels as well as the residuals from systematic errors and foregrounds. We also consider a cumulative channel of the three mentioned. We produce the sky (mock data) for the CMB multipoles CTTl , CTEl , CEEl , and CBBl from the ΛCDMr and ΛCDMrT models and obtain the cosmological parameter marginalized likelihood distributions for the two models. Foreground residuals affect only the cosmological parameters sensitive to the B modes. As expected, the likelihood r distribution is more clearly peaked near the fiducial value (r = 0.0427) in the ΛCDMrT model than in the ΛCDMr model. The best value for r in the presence of residuals turns out to be about r ≅ 0.04 for both the ΛCDMr and the ΛCDMrT models. The ΛCDMrT model is very stable; its distributions do not change by including residuals and the B modes. For r we find 0.028 < r < 0.116 at a 95% confidence level (CL) with the best value r = 0.04. We also compute the B mode detection probability by the most sensitive HFI-143 channel. At the level of foreground residual equal to 30% of our toy model, only a 68% CL (1σ) detection is very likely. For a 95% CL detection (2σ), the level of foreground residual should be reduced to 10% or lower of the adopted toy model. The lower bounds (and most probable value) we infer for r support the searching of CMB B-mode polarization in the current data as well as the planned CMB missions oriented toward B polarization.
[en] We discuss the effects on the cosmic microwave background (CMB), cosmic infrared background (CIB), and thermal Sunyaev-Zeldovich effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. After a brief review of the current observational and theoretical status, we investigate the scientific perspectives opened by future CMB space missions, focussing on the Cosmic Origins Explorer (CORE) proposal. The improvements in sensitivity offered by a mission like CORE, together with its high resolution over a wide frequency range, will provide a more accurate estimate of the CMB dipole. The extension of boosting effects to polarization and cross-correlations will enable a more robust determination of purely velocity-driven effects that are not degenerate with the intrinsic CMB dipole, allowing us to achieve an overall signal-to-noise ratio of 13; this improves on the Planck detection and essentially equals that of an ideal cosmic-variance-limited experiment up to a multipole ℓ2000. Precise inter-frequency calibration will offer the opportunity to constrain or even detect CMB spectral distortions, particularly from the cosmological reionization epoch, because of the frequency dependence of the dipole spectrum, without resorting to precise absolute calibration. The expected improvement with respect to COBE-FIRAS in the recovery of distortion parameters (which could in principle be a factor of several hundred for an ideal experiment with the CORE configuration) ranges from a factor of several up to about 50, depending on the quality of foreground removal and relative calibration. Even in the case of 1 % accuracy in both foreground removal and relative calibration at an angular scale of 1o, we find that dipole analyses for a mission like CORE will be able to improve the recovery of the CIB spectrum amplitude by a factor 17 in comparison with current results based on COBE-FIRAS. In addition to the scientific potential of a mission like CORE for these analyses, synergies with other planned and ongoing projects are also discussed.