Planck2018 results

Abstract

We present full-sky maps of the cosmic microwave background (CMB) and polarized synchrotron and thermal dust emission, derived from the third set of Planck frequency maps. These products have significantly lower contamination from instrumental systematic effects than previous versions. The methodologies used to derive these maps follow closely those described in earlier papers, adopting four methods (Commander, NILC, SEVEM, and SMICA) to extract the CMB component, as well as three methods (Commander, GNILC, and SMICA) to extract astrophysical components. Our revised CMB temperature maps agree with corresponding products in the Planck 2015 delivery, whereas the polarization maps exhibit significantly lower large-scale power, reflecting the improved data processing described in companion papers; however, the noise properties of the resulting data products are complicated, and the best available end-to-end simulations exhibit relative biases with respect to the data at the few percent level. Using these maps, we are for the first time able to fit the spectral index of thermal dust independently over 3 • regions. We derive a conservative estimate of the mean spectral index of polarized thermal dust emission of β d = 1.55 ± 0.05, where the uncertainty marginalizes both over all known systematic uncertainties and different estimation techniques. For polarized synchrotron emission, we find a mean spectral index of β s = −3.1 ± 0.1, consistent with previously reported measurements. We note that the current data processing does not allow for construction of unbiased single-bolometer maps, and this limits our ability to extract CO emission and correlated components. The foreground results for intensity derived in this paper therefore do not supersede corresponding Planck 2015 products. For polarization the new results supersede the corresponding 2015 products in all respects.

Possible Effects of the Fractal Distribution of Relic Wormholes

“…We point out that, in the flat space, the light when passing through a wormhole throat is too scattered and may contribute only to the diffuse background radiation [26]. Most likely, the scattered signal is too dim to observe a separate galaxy through wormhole throats.…”

The large scale polarization explorer (LSPE) for CMB measurements: performance forecast

“…Component separation is a key element in CMB data analysis, and it turns out to be particularly challenging for the extraction of CMB polarization (see e.g. [118][119][120]). In particular, diffuse Galactic dust and synchrotron emissions are the most relevant foregrounds in polarization.…”

Primordial information content of Rayleigh anisotropies

“…The smallness of the Rayleigh signal will make it hard to detect, but the guaranteed signal is definitely within reach of upcoming CMB experiments, and the potentially large foregrounds (discussed at the end of Sec. II) can generally be distinguished because of unique frequency dependence [71,72] and are relatively small when considered in comparison to those that, for example, hinder all cosmological 21 cm observations [73,74].…”