Details

Autor(en) / Beteiligte

• de Graauw, T.
• Caux, E.
• Gusten, R.
• Jellema, W.
• Luinge, W.
• Pearson, J.
• Phillips, T.
• Schieder, R.
• Stutzki, J.
• Wafelbakker, K.
• Whyborn, N.
• Wildeman, K.

Titel

The Herschel-Heterodyne Instrument for the Far-Infrared (HIFI)

Ist Teil von

• Infrared and Millimeter Waves, Conference Digest of the 2004 Joint 29th International Conference on 2004 and 12th International Conference on Terahertz Electronics, 2004, 2004, p.579-580

Ort / Verlag

IEEE

Erscheinungsjahr

2004

Quelle

IEEE

Beschreibungen/Notizen

• The Heterodyne Instrument for the Far-Infrared (HIFI) is a single sky-pixel, high-resolution (>300.000), spectrometer for ESA's Herschel Space Observatory. The instrument is designed to provide a wide and continuous frequency coverage with a velocity resolved resolution and a high sensitivity. This allows detailed investigations of a wide variety of astronomical sources, ranging from solar system objects, star formation regions to nuclei of galaxies. The frequency bands cover many emission and absorption lines of molecules, like H/sub 2/O, and atomic and ionic lines, like CII, NII. The instrument comprises of 5 frequency bands covering 480-150 GHz with SIS mixers and a sixth dual band for the 1410-1910 GHz range with Hot Electron Bolometer Mixers. The Local Oscillator (LO) subsystem consists of a Ka-band synthesiser followed by 14 chains of frequency multipliers, 2 for each frequency band. Each frequency band has two mixers operating on orthogonal polarisations. All mixers are designed to have a noise performance close to the quantum noise limit. One frequency band is operated at a time. Modular design of the Focal Plane Unit, with a common optical path for all the mixer bands, and of the Local Oscillator Unit with a common LO Source Unit for all the LO chains, make the instrument very compact. A pair of Auto-Correlators and a pair of Acousto-Optic spectrometers process the two IF signals from the dual-polarisation front-ends and provide instantaneous frequency coverage of 4 GHz, resulting in a set of resolutions (140 KHz to 1 MHz), better than <0.1 Km/s. The instrument development is in an advanced state with mixers and LO chains approaching aimed performance.