A&A Supplement Ser., Vol. 124, September 1997, 573-577

Received November 8; accepted December 2, 1996

LonGSp: The Gornergrat longslit infrared spectrometer

L. Vanzi, M. Sozzi, G. Marcucci, A. Marconi, F. Mannucci, F. Lisi, L. Hunt, E. Giani, S. Gennari, V. Biliotti, and C. Baffa

Send offprint request: L. Vanzi

  Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 5, I-50125 Firenze, Italy
  Centro per l'Astronomia Infrarossa e lo Studio del Mezzo Interstellare-CNR, Largo E. Fermi 5, I-50125 Firenze, Italy
  Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy

Abstract:

We present a near-infrared cooled grating spectrometer that has been developed at the Arcetri Astrophysical Observatory for the 1.5 m Infrared Telescope at Gornergrat (TIRGO).

The spectrometer is equipped with cooled reflective optics and a grating in Littrow configuration. The detector is an engineering grade Rockwell NICMOS3 array ( pixels of ). The scale on the focal plane is 1.73 arcsec/pixel and the field of view along the slit is 70 arcsec. The accessible spectral range is with a dispersion, at first order, of about 11.5 Å/pixel. This paper presents a complete description of the instrument, including its optics and cryo-mechanical system, along with astronomical results from test observations, started in 1994. Since January 1996, LonGSp is offered to TIRGO users and employed in several Galactic and extragalactic programs.

keywords: instrumentation: spectrometers -- infrared: general

 
• 1. Introduction
• 2. Optical design
• 3. Cryogenics and mechanics
• 4. Electronics and software
• 5. Detector performance
• 6. Observations and data reduction
• 7. Astronomical results
• References