LiteBIRD: JAXA's new strategic L-class mission for all-sky surveys of cosmic microwave background polarization

TL;DR

LiteBIRD is a planned space mission by JAXA aiming to map the cosmic microwave background polarization with unprecedented precision to investigate cosmic inflation and fundamental physics.

Contribution

This paper presents the design, scientific goals, and expected outcomes of LiteBIRD, a new strategic L-class mission dedicated to all-sky CMB polarization surveys.

Findings

Designed to detect or rule out inflationary B-mode signals

Full-sky surveys over 15 frequency bands for 3 years

Expected sensitivity of 2.16 micro K-arcmin

Abstract

LiteBIRD, the Lite (Light) satellite for the study of B-mode polarization and Inflation from cosmic background Radiation Detection, is a space mission for primordial cosmology and fundamental physics. JAXA selected LiteBIRD in May 2019 as a strategic large-class (L-class) mission, with its expected launch in the late 2020s using JAXA's H3 rocket. LiteBIRD plans to map the cosmic microwave background (CMB) polarization over the full sky with unprecedented precision. Its main scientific objective is to carry out a definitive search for the signal from cosmic inflation, either making a discovery or ruling out well-motivated inflationary models. The measurements of LiteBIRD will also provide us with an insight into the quantum nature of gravity and other new physics beyond the standard models of particle physics and cosmology. To this end, LiteBIRD will perform full-sky surveys for three years at the Sun-Earth Lagrangian point L2 for 15 frequency bands between 34 and 448 GHz with three telescopes, to achieve a total sensitivity of 2.16 micro K-arcmin with a typical angular resolution of 0.5 deg. at 100GHz. We provide an overview of the LiteBIRD project, including scientific objectives, mission requirements, top-level system requirements, operation concept, and expected scientific outcomes.