Planck 2013 results. III. LFI systematic uncertainties

We discuss the discordance between the estimated values of the cosmological parameters from Planck assuming the concordance ΛCDM model and low-redshift measurements. In particular, we consider the Hubble constant mismatch between Planck temperature constraint for the ΛCDM model and the Riess et al. [1] local measurements as well as the discordance between the estimated value of S8 from Planck and some weak lensing surveys such as Kilo Degree Survey (KiDS-450) and Dark Energy Survey (DES) observations. The discordance can come from a wide range of non-standard cosmological or astrophysical processes as well as from some particular systematics of the observations. In this paper, without considering any particular astrophysical process or extension to the standard model at the background level, we seek solely to project the effect of these differences in the values of the key cosmological parameters on to the shape of the primordial power spectrum (PPS) . In order to realise this goal, we uncover the shape of the PPS by implementing the Modified Richardson-Lucy algorithm (MRL) that fits the Planck temperature data as acceptably as the case of the standard model of cosmology, but with a Hubble constant consistent with local measurements as well as improving the consistency between the derived S8 and σ8 parameters with estimations of the weak lensing surveys.

Section: Introductionmentioning

confidence: 75%

Parameter discordance in Planck CMB and low-redshift measurements: projection in the primordial power spectrum

Hazra

Shafieloo

Souradeep

2019

“…In general we want this uncertainty to be much less than that imposed by the white noise. Following the approach already adopted for Planck-LFI [100,101] we set this limit to 5% of the white noise level as a goal and 10% of the white noise level as a requirement. In table 5 we provide a list of systematic effects that could affect Strip polarimetric measurements and goal/requirement values for the upper limit in the systematic uncertainty.…”

Section: Lspe-strip Systematic Effectsmentioning

confidence: 99%

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

Addamo

Ade

Baccigalupi

et al. 2021

Self Cite

The measurement of the polarization of the Cosmic Microwave Background (CMB) radiation is one of the current frontiers in cosmology. In particular, the detection of the primordial divergence-free component of the polarization field, the B-mode, could reveal the presence of gravitational waves in the early Universe. The detection of such a component is at the moment the most promising technique to probe the inflationary theory describing the very early evolution of the Universe. We present the updated performance forecast of the Large Scale Polarization Explorer (LSPE), a program dedicated to the measurement of the CMB polarization. LSPE is composed of two instruments: LSPE-Strip, a radiometer-based telescope on the ground in Tenerife-Teide observatory, and LSPE-SWIPE (Short-Wavelength Instrument for the Polarization Explorer) a bolometer-based instrument designed to fly on a winter arctic stratospheric long-duration balloon. The program is among the few dedicated to observation of the Northern Hemisphere, while most of the international effort is focused into ground-based observation in the Southern Hemisphere. Measurements are currently scheduled in Winter 2022/23 for LSPE-SWIPE, with a flight duration up to 15 days, and in Summer 2022 with two years observations for LSPE-Strip. We describe the main features of the two instruments, identifying the most critical aspects of the design, in terms of impact on the performance forecast. We estimate the expected sensitivity of each instrument and propagate their combined observing power to the sensitivity to cosmological parameters, including the effect of scanning strategy, component separation, residual foregrounds and partial sky coverage. We also set requirements on the control of the most critical systematic effects and describe techniques to mitigate their impact. LSPE will reach a sensitivity in tensor-to-scalar ratio of σ r < 0.01, set an upper limit r < 0.015 at 95% confidence level, and improve constraints on other cosmological parameters.

“…However, the way in which systematic effects impact the science products of the mission is far from trivial (e.g. [62]). In general it is necessary to simulate systematic effects and propagate them through the data analysis pipeline up to the cosmological results, with an accuracy and a level of detail that depends on the significance of the specific effect being evaluated.…”

Section: Instrument Calibrationmentioning

confidence: 99%

Exploring cosmic origins with CORE: The instrument

Bernardis

Ade

Baselmans

et al. 2018

Self Cite

We describe a space-borne, multi-band, multi-beam polarimeter aiming at a precise and accurate measurement of the polarization of the Cosmic Microwave Background. The instrument is optimized to be compatible with the strict budget requirements of a mediumsize space mission within the Cosmic Vision Programme of the European Space Agency. The instrument has no moving parts, and uses arrays of diffraction-limited Kinetic Inductance Detectors to cover the frequency range from 60 GHz to 600 GHz in 19 wide bands, in the focal plane of a 1.2 m aperture telescope cooled at 40 K, allowing for an accurate extraction of the CMB signal from polarized foreground emission. The projected CMB polarization survey sensitivity of this instrument, after foregrounds removal, is 1.7 µK•arcmin. The design is robust enough to allow, if needed, a downscoped version of the instrument covering the 100 GHz to 600 GHz range with a 0.8 m aperture telescope cooled at 85 K, with a projected CMB polarization survey sensitivity of 3.2 µK•arcmin.