Planck pre-launch status: HFI ground calibration

¹ Institut d'Astrophysique Spatiale, Bât. 121, Université Paris Sud-11, 91405 Orsay, France e-mail: francois.pajot@ias.u-psud.fr
² Astronomy and Instrumentation Group, Cardiff University, Cardiff, Wales, UK
³ Laboratoire de l'Accélérateur Linéaire, Université Paris Sud-11, 91405 Orsay, France
⁴ Laboratoire Astroparticule et Cosmologie (APC), UMR 7164, CNRS & Université Paris Diderot – Paris 7, 10 rue A. Domon et L. Duquet, 75205 Paris Cedex 13, France
⁵ Institut Néel, CNRS/UJF, 25 rue des Martyrs, BP 166, 38042 Grenoble Cedex 9, France
⁶ LERMA, CNRS, Observatoire de Paris, 61 Avenue de l'Observatoire, 75014 Paris, France
⁷ Department of Physics, California Institute of Technology, Mail code:59-33, Pasadena, CA 91125, USA
⁸ Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
⁹ Gruppo di Cosmologia Sperimentale, Dipart. di Fisica, Univ. La Sapienza, P. A. Moro 2, 00185 Roma, Italy
¹⁰ Institut d'Astrophysique de Paris, UMR7095, CNRS and Université Pierre & Marie Curie-Paris-6, 98 bis boulevard Arago, 75014 Paris, France
¹¹ Laboratoire d'Astrophysique, Obs. de Grenoble, BP 53, 38041 Grenoble Cedex 9, France
¹² Centre d'Etude Spatiale des Rayonnements, CNRS, 9 Avenue du Colonel Roche, BP 4346, 31028 Toulouse, France
¹³ Princeton University, Department of Physics, Joseph Henry Laboratory, USA
¹⁴ LPSC, Université Joseph Fourier Grenoble I, CNRS/IN2P3, Institut National Polytechnique de Grenoble, 53 Avenue des Martyrs, 38026 Grenoble Cedex, France
¹⁵ CNES, Centre spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France
¹⁶ The University of Manchester, School of Physics and Astronomy, Alan Turing Building, Manchester M13 9PL, UK
¹⁷ Optical Science Laboratory, University College London, Gower Street, WC1E 6BT London, UK
¹⁸ CEA-CE Saclay, DAPNIA, Service de Physique des Particules, Bât. 141, 91191 Gif-sur-Yvette Cedex, France

Received: 28 August 2009
Accepted: 15 March 2010

Abstract

Context. The Planck satellite was successfully launched on May 14th 2009. We have completed the pre-launch calibration measurements of the High Frequency Instrument (HFI) on board Planck and their processing.

Aims. We present the results ot the pre-launch calibration of HFI in which we have multiple objectives. First, we determine instrumental parameters that cannot be measured in-flight and predict parameters that can. Second, we take the opportunity to operate and understand the instrument under a wide range of anticipated operating conditions. Finally, we estimate the performance of the instrument built.

Methods. We obtained our pre-launch calibration results by characterising the component and subsystems, then by calibrating the focal plane at IAS (Orsay) in the Saturne simulator, and later from the tests at the satellite level carried out in the CSL (Liège) cryogenic vacuum chamber. We developed models to estimate the instrument pre-launch parameters when no measurement could be performed.

Results. We reliably measure the Planck-HFI instrument characteristics and behaviour, and determine the flight nominal setting of all parameters. The expected in-flight performance exceeds the requirements and is close or superior to the goal specifications.