Archeops: A CMB anisotropy balloon experiment
measuring a broad range of angular scales

the Archeops Collaboration

from the following institutes:
California Institute of Technology, Pasadena USA
Centre d'Etude Spatiale des Rayonnements, Toulouse France
Centre de spectrométrie nucléaire et de spectrométrie de masse, Orsay France
Colllège de France, Paris France
DAPNIA CEA, Saclay France
Institut d'Astrophysique de Paris, Paris France
Institut d'Astrophysique Spatiale, Orsay France
Institut des Sciences Nucléaires de Grenoble, Grenoble France
IROE CNR, Firenze Italy
Jet Propulsion Laboratory, Pasadena USA
Laboratoire de l'accélérateur linéaire, Orsay France
Landau Institute of Theoretical Physics, Moscow Russia
Observatoire Midi-Pyrénées, Toulouse France
Queen Mary and Westfield College, London UK
Universita di Roma La Sapienza, Roma Italy
University of Minnesota at Minneapolis USA

Abstract:

The Cosmic Microwave Background Radiation is the oldest photon radiation that can be observed, having been emitted when the Universe was about 300,000 year old. It is a blackbody at 2.73 K, and is almost perfectly isotropic, the anisotropies being about one part to 100,000. However, these anisotropies, detected by the COBE satellite in 1992, constrain the cosmological parameters such as the curvature of the Universe.

Archeops is a balloon-borne experiment designed to map these anisotropies. The instrument is composed of a 1.5 m telescope and bolometers cooled at 85 mK to detect radiation between 150 and 550 GHz. To lower parasitic signals, the instrument is borne by a stratospheric balloon during the arctic night. This instrument is also a preparation for the Planck satellite mission, as its design is similar to HFI.

We discuss here the results of the first scientific flight from Esrange (near Kiruna, Sweden) to Russia on January 29th 2001, which led to a 22% (sub)millimetre sky coverage unprecedented at this resolution. Here, we put some emphasis on interstellar dust foreground emission observations.