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Anomalous Microwave Emission (AME) is a significant component of Galactic diffuse emission in the frequency range 10–60GHz and a new window into the properties of sub-nanometre-sized grains in the interstellar medium. We investigate the morphology of AME in the ≈10○ diameter λ Orionis ring by combining intensity data from the QUIJOTE experiment at 11, 13, 17, and 19GHz and the C-Band All Sky Survey (C-BASS) at 4.76GHz⁠, together with 19 ancillary data sets between 1.42 and 3000GHz⁠. Maps of physical parameters at 1○ resolution are produced through Markov chain Monte Carlo (MCMC) fits of spectral energy distributions (SEDs), approximating the AME component with a lognormal distribution. AME is detected in excess of 20σ at degree-scales around the entirety of the ring along photodissociation regions (PDRs), with three primary bright regions containing dark clouds. A radial decrease is observed in the AME peak frequency from ≈35GHz near the free–free region to ≈21GHz in the outer regions of the ring, which is the first detection of AME spectral variations across a single region. A strong correlation between AME peak frequency, emission measure and dust temperature is an indication for the dependence of the AME peak frequency on the local radiation field. The AME amplitude normalized by the optical depth is also strongly correlated with the radiation field, giving an overall picture consistent with spinning dust where the local radiation field plays a key role., Partial financial support for QUIJOTE is provided by the Spanish Ministry of Economy and Competitiveness (MINECO) under the projects AYA2007-68058-C03-01, AYA2010-21766-C03-02, AYA2014-60438-P, AYA2017-84185-P, IACA13-3E-2336, IACA15-BE-3707, and EQC2018-004918-P; Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, UE), under projects ESP2017-83921-C2-1-R and AYA2017-90675-REDC; the European Union’s Horizon 2020 research and innovation programme under grant agreement number 687312 (RADIOFORE; FP acknowledges support from the Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN) under grant numbers ESP2015-65597-C4-4-R, ESP2017-86852-C4-2-R, ESP2015-65597-C4-4-R, and ESP2017-86852-C4-2-R. GROUNDS) and number 658499 (PolAME); Unidad de Excelencia María de Maeztu (MDM-2017-0765)

We present a methodology to recover cosmic microwave background (CMB) polarization in which the quantity P = Q + iU is linearly combined at different frequencies using complex coefficients. This is the most general linear combination of the Q and U Stokes parameters which preserves the physical coherence of the residual contribution on the CMB estimation. The approach is applied to the internal linear combination (ILC) and the internal template fitting (ITF) methodologies. The variance of P of the resulting map is minimized to compute the coefficients of the linear combination. One of the key aspects of this procedure is that it serves to account for a global frequency-dependent shift of the polarization phase. Although in the standard case, in which no global E-B transference depending on frequency is expected in the foreground components, minimizing 〈|P|2〉 is similar to minimizing 〈Q2〉 and 〈U2〉 separately (as previous methodologies proceed), multiplying Q and U by different coefficients induces arbitrary changes in the polarization angle and it does not preserve the coherence between the spinorial components. The approach is tested on simulations, obtaining a similar residual level with respect to the one obtained with other implementations of the ILC, and perceiving the polarization rotation of a toy model with the frequency dependence of the Faraday rotation., Partial financial support from the Spanish Ministerio de Economía y Competitividad Projects AYA2010-21766-C03-01, AYA2012-39475-C02-01 and Consolider-Ingenio 2010 CSD2010-00064 is acknowledged.

Several statistical anomalies in the cosmic microwave background (CMB) temperature anisotropies seem to defy the assumption of a homogeneous and isotropic universe. In particular, a dipole modulation has been detected both in WMAP and Planck data. We adapt the methodology proposed by Eriksen et al. on CMBdata to galaxy surveys, tracing the large-scale structure. We analyse the National Radio Astronomy Observatory (NRAO) and Very Large Array (VLA) Sky Survey data at a resolution of ~2° for three different flux thresholds: 2.5, 5.0 and 10.0 mJy, respectively. No evidence of a dipole modulation is found. This result suggests that the origin of the dipole asymmetry found in the CMB cannot be assigned to secondary anisotropies produced at redshifts around z=1. However, it could still have been generated at redshifts higher or lower, such as the integrated Sachs-Wolfe effect produced by the local structures. Other all-sky surveys, like the infrared WISE catalogue, could help to explore with a high sensitivity a redshift interval closer than the one probed with NVSS. © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society., We acknowledge partial financial support from the Spanish Ministerio de Economía y Competitividad Projects HI2008-0129, AYA2010-21766-C03-01, AYA2012-39475-C02-01 and Consolider-Ingenio 2010 CSD2010-00064. RFC thanks financial support from Spanish CSIC for a JAE-predoc fellowship, cofinanced by the European Social Fund.

Recent results of the ESA Planck satellite have confirmed the existence of some anomalies in the statistical distribution of the cosmic microwavebackground (CMB) anisotropies. One of the most intriguing anomalies is the cold spot, first detected in the Wilkinson Microwave Anisotropy Probe (WMAP) data by Vielva et al. In a later paper, Vielva et al. (2011) developed a method to probe the anomalous nature of the cold spot by using the cross-correlation of temperature and polarization of the CMB fluctuations. Whereas this work was built under the assumption of analysing full-sky data, in this paper we extend such approach to deal with realistic data sets with a partial-sky coverage. In particular, we exploit the radial and tangential polarization patterns around temperature spots. We explore the capacity of the method to distinguish between a standard Gaussian CMB scenario and an alternative one, in which the cold spot arises from a physical process that doesnot present correlated polarization features (e.g. topological defects), asa function of the instrumental-noise level. Moreover, we consider more in detail the case of an ideal noise-free experiment and the ones with the expected instrumental-noise levels in QUIJOTE and Planck experiments. We also present an application to the 9-year WMAP data, without being able to obtainfirm conclusions, with a significance level of 32 per cent. In the ideal case, the alternative scenario could be rejected at a significance level of around 1 per cent, whereas for expected noise levels of QUIJOTE and Planck experiments the corresponding significance levels are 1.5 and 7.4 per cent, respectively. © 2013 The Authors, Published by Oxford University Press on behalf of the Royal Astronomical Society., We acknowledge partial financial support from the Spanish Ministerio de Economía y Competitividad Projects AYA2010-21766-C03-01, AYA2012-39475-C02-01 and Consolider-Ingenio 2010 CSD2010-00064. RFC thanks financial support from Spanish CSIC for a JAE-predoc fellowship, cofinanced by the European Social Fund.

We present a map of the cosmic microwave background (CMB) anisotropies induced by the late integrated Sachs-Wolfe effect. The map is constructed by combining the information of the Wilkinson Microwave Anisotropy Probe 7-yr CMB data and the NRAO VLA Sky Survey (NVSS) through a linear filter. This combination improves the quality of the map that would be obtained using information only from the large-scale structure data. In order to apply the filter, a given cosmological model needs to be assumed. In particular, we consider the standard Λ cold dark matter model. As a test of consistency, we show that the reconstructed map is in agreement with the assumed model, which is also favoured against a scenario where no correlation between the CMB and NVSS catalogue is considered. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society., We acknowledge partial financial support from the Spanish Ministerio de Economía y Competitividad AYA2010-21766-C03-01 and Consolider-Ingenio 2010 CSD2010- 00064 projects. PV also acknowledges financial support from the Ramón y Cajal programme and AMCthanks the Spanish Ministerio de Economía y Competitividad for a pre-doctoral fellowship. We also acknowledge the use of Legacy Archive for Microwave Background Data Analysis (LAMBDA). Support for it is provided by the NASA Office of Space Science.

We use a quadratic maximum likelihood (QML) method to estimate the angular power spectrum of the cross-correlation between cosmic microwave background and large-scale structure maps as well as their individual auto-spectra. We describe our implementation of this method and demonstrate its accuracy on simulated maps. We apply this optimal estimator to Wilkinson Microwave Anisotropy Probe (WMAP) 7-yr and National Radio Astronomical Observatory (NRAO) Very Large Array Sky Survey (NVSS) data and explore the robustness of the angular power spectrum estimates obtained by the QML method. With the correction of the declination systematics in NVSS, we can safely use most of the information contained in this survey. We then make use of the angular power spectrum estimates obtained by the QML method to derive constraints on the dark energy critical density in a flat Λ cold dark matter model by different likelihood prescriptions. When using just the cross-correlation between WMAP 7-yr and NVSS maps with 1°.8 resolution, the best-fitting model has a cosmological constant of approximately 70 per cent of the total energy density, disfavouring an Einstein–de sitter universe at more than 2σ confidence level., This work is supported by ASI through ASI/INAF Agreement I/072/09/0 for the Planck LFI Activity of Phase E2. PV, RBB, AMC and EMG acknowledge partial financial support from the Spanish Ministerio de Ciencia e Innovación project AYA2010-21766-C03-01 and the Consolider Ingenio-2010 Programme project CDS2010-00064, and PV also acknowledges financial support from the Ramón y Cajal programme. RGC is supported by STFC grant ST/H002774/1.