In-flight calibration and verification of the Planck-LFI instrument

TL;DR

This paper details the in-flight calibration and performance verification of the Planck-LFI instrument, demonstrating successful calibration activities that enhanced noise performance and confirmed ground test results.

Contribution

It presents the first comprehensive account of in-flight calibration procedures and results for the Planck-LFI instrument, including tuning and performance assessment.

Findings

Calibration activities were successfully completed in space.

Instrument response matched ground test results.

In-flight tuning improved noise performance for some channels.

Abstract

In this paper we discuss the Planck-LFI in-flight calibration campaign. After a brief overview of the ground test campaigns, we describe in detail the calibration and performance verification (CPV) phase, carried out in space during and just after the cool-down of LFI. We discuss in detail the functionality verification, the tuning of the front-end and warm electronics, the preliminary performance assessment and the thermal susceptibility tests. The logic, sequence, goals and results of the in-flight tests are discussed. All the calibration activities were successfully carried out and the instrument response was comparable to the one observed on ground. For some channels the in-flight tuning activity allowed us to improve significantly the noise performance.