Planckpre-launch status: The optical system

Abstract

Planck is a scientific satellite that represents the next milestone in space-based research related to the cosmic microwave background, and in many other astrophysical fields. Planck was launched on 14 May of 2009 and is now operational. The uncertainty in the optical response of its detectors is a key factor allowing Planck to achieve its scientific objectives. More than a decade of analysis and measurements have gone into achieving the required performances. In this paper, we describe the main aspects of the Planck optics that are relevant to science, and the estimated in-flight performance, based on the knowledge available at the time of launch. We also briefly describe the impact of the major systematic effects of optical origin, and the concept of in-flight optical calibration. Detailed discussions of related areas are provided in accompanying papers.

Planckpre-launch status: ThePlanckmission

“…The knowledge of the beams achieved on the ground (Tauber et al 2010) is close to, but not enough to achieve the calibration accuracy goals (1% at all multipoles up to 2000 in the 70-217 GHz frequency channels, and 3% at other frequencies). It will be supplemented with measurements of planets during flight (see Sect.…”

“…See Lamarre et al (2010). (b) Band-averaged, including polarised and unpolarised detectors, see Tauber et al (2010).…”

“…(c) Band-averaged, including polarised and unpolarised detectors, see Tauber et al (2010). (d) In μK/K (thermodynamic temperature) for 15 months integration, 1σ, for square pixels whose sides are given in the row "Mean FWHM".…”

“…A detailed description of the Planck telescope and the instrument optics is provided in Tauber et al (2010), Sandri et al (2010) and Maffei et al (2010). The LFI horns are situated in a ring around the HFI, see Fig.…”

“…- Tauber et al (2010), describing the optical performance of the combined payload, i.e. telescope plus instruments; - Mandolesi et al (2010), describing programmatic aspects of the LFI and its development; - Bersanelli et al (2010), describing in detail the design of the LFI; - Mennella et al (2010), describing the test and calibration programme of the LFI at instrument and system levels prior to launch; - , describing the test and calibration of the LFI radiometer chains; - Sandri et al (2010), describing the design and test of the LFI optics; - Leahy et al (2010), describing the polarisation aspects of the LFI, and its expected performance in orbit; - Lamarre et al (2010), describing in detail the on-ground design, manufacture, test and performance of the HFI; - Pajot et al (2010), describing the test and calibration programme of the HFI prior to launch; - Ade et al (2010), describing the design, test and performance of the cryogenic elements of the HFI focal plane; - Holmes et al (2008), describing the design, manufacture and test of the HFI bolometers; - Maffei et al (2010), describing the design and test of the HFI optics; - Rosset et al (2010), describing the polarisation aspects of the HFI.…”