Summary

4MOST will be a wide-field, high-multiplex, fibre-fed, optical spectroscopic survey facility to be mounted on ESO's 4-m-class telescope VISTA and operated in ESO's Paranal Observatory operational environment. 4MOST will be the only instrument installed at VISTA and will be entirely dedicated to observations for ESO Public Surveys. Apart from the instrument itself, the facility will also include the Operations and Data Management Systems necessary for the planning, scheduling and execution of the observations, and for the reduction, analysis, validation and publication of the data and high-level data products.

4MOST will feature a 2.5-degree diameter field-of-view with 2436 science fibres in the focal plane. The fibres will be configured by a fibre positioner based on the tilting spine principle, enabling extremely short reconfiguration times. The fibres feed three, fixed-configuration spectrographs: one third of the fibres (i.e. 812) will go to a single high-resolution spectrograph (HRS) with resolution R ≈ 18000 – 21000, while the remaining 1624 fibres will feed two low-resolution spectrographs (LRS) with resolution R ≈ 4000 – 7500. In each spectrograph the light is split into three different wavelength channels (blue, green and red) before being dispersed by VPH gratings and recorded by identical 6k × 6k E2V CCDs with low readout noise. The instrument will also feature a Wide Field Corrector with an Atmospheric Dispersion Corrector, an Acquisition & Guiding and Wavefront Sensor system, as well as Metrology and Calibration systems..

Detailed information about the instrument can be found in the 4MOST Consortium webpage.

Contact Information

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Content of these pages

The following items are available on all the CRIRES pages, using the bar on the left.

• Overview: a short description of the instrument
• News: list of changes affecting the instrument and/or its pages.
• Instrument Description: all the important parameters of the instrument.
• Manuals: links to all the documents related to CRIRES.
• Tools: a collection of useful tools and informations for preparing and analyzing the CRIRES observations.
• Instrument Operations Team
• Visitor Instructions: Instrument specific instructions for Visiting Astronomers
• Science: Science done with CRIRES, incl. during Science Verification