VIMOS spectrograph

VIMOS
VIsible imaging Multi-Object Spectrograph

mounted at the Nasmyth focus of MELIPAL, the third of the four 8.2m ESO-VLT Unit Telescopes in Paranal, Chile.

Current status:VIMOS offered to the community for P71 April-September 2003:
ESO call for proposals to be issued October 25, 2002, answer due by November 5th, 2002.

VIMOS User's Manual - V1 (pdf file)

Overall Performances
Imaging characteristics & performances

Multi-slit spectroscopy characteristics & performances

Integral field spectroscopy characteristics & performances

Outlay of the VIMOS Field of View

Design Overview

Manufacturing

Instrument status at OHP, France on the 28 July 2000.

Technical First Light at OHP, France, May 2000.

Links:
OAC-Technology Working Group

ESO VIMOS web page

OVERALL PERFORMANCES

IMAGING CHARACTERISTICS & PERFORMANCES

Configuration Filter inserted in the beam

Field
4 x 7'x8'

slight vignetting on the corners out to the 8' field

corresponding CCD area: 2048 x 2350 pixel²

Sampling 0.205 arcsec / pixel

Throughput (instrument only)
3700 to 5200 Angs: 60% to 80%

above 5200 Angs: 80% to 84%

Filters 10 filters at any time, U'BVRIz standard set

Limiting magnitudes in 1h (Ag coated UT)
V = 27.7, I = 26.6, 5sigma detection for a point source

V = 26.5, I = 25.4, 5sigma detection in 3" aperture for a galaxy

MULTI-SLIT SPECTROSCOPY CHARACTERISTICS & PERFORMANCES

Configuration Grisms inserted in the beams

Field
Slit selection is in 4 x 7'x8'

The cameras image spectra on the full 2048 x 4096 pixel² CCD area

Slit length
7' per beam in "single layer" mode = 28' total length

5 x 7' per beam in 5 spectra layers mode = 140' total length

Slit masks 4 masks, each ~ 300 x 300mm, laser cut

Multiplex ~ 800 simultaneous slits, each 10 arcsec long, at R ~ 200

Slit sampling 4.88 pixels for one arcsec slit

Slit width & length Larger than 0.35 arcsec, any length and shape

Grisms 75 to 720 gr/mm rulings

Dispersions 6.3 Ang/pixel to 0.53 Ang/pixel

Resolutions R = 180 to 2520 (1 arcsec slit)

Limiting magnitudes in 1h (Ag coated UT) I = 24.1, 5sigma, R ~ 200; I = 22.7, 5sigma, R ~ 2500

INTEGRAL FIELD SPECTROSCOPY CHARACTERISTICS & PERFORMANCES

Configuration Input fiber selection, special masks in place

Field 1' x 1' and 24" x 24"

Design 6400 microlenses coupled to fibers, fibers coupled to 4 output long slits per channel

Wavelength range 3700 to 10000 Angs (Silica microlens array)

Spectral resolution Same as for MOS with 1" equivalent slit

Outlay of the VIMOS Field of View

DESIGN OVERVIEW
(click on postage stamps to get full resolution images)

Design Assembly Design View

Optics

Opto-Mechanical Layout

Mechanical Sub-Systems

Integral Field Unit

Co-rotator

MANUFACTURING
(click on postage stamps to get full resolution images)

Integration hall

at OHP, France

Instrument

Optics

Grisms
Filters

Grism data and curves, Grism dimensions

Filters data and curves

Structure

Mechanical sub-assemblies

Integral Field Unit

IFU, mask modules

Detectors, see also

ESO optical detector team

Test Tools

Configuration	Filter inserted in the beam
Field	4 x 7'x8' slight vignetting on the corners out to the 8' field corresponding CCD area: 2048 x 2350 pixel²
Sampling	0.205 arcsec / pixel
Throughput (instrument only)	3700 to 5200 Angs: 60% to 80% above 5200 Angs: 80% to 84%
Filters	10 filters at any time, U'BVRIz standard set
Limiting magnitudes in 1h (Ag coated UT)	V = 27.7, I = 26.6, 5sigma detection for a point source V = 26.5, I = 25.4, 5sigma detection in 3" aperture for a galaxy

Configuration	Grisms inserted in the beams
Field	Slit selection is in 4 x 7'x8' The cameras image spectra on the full 2048 x 4096 pixel² CCD area
Slit length	7' per beam in "single layer" mode = 28' total length 5 x 7' per beam in 5 spectra layers mode = 140' total length
Slit masks	4 masks, each ~ 300 x 300mm, laser cut
Multiplex	~ 800 simultaneous slits, each 10 arcsec long, at R ~ 200
Slit sampling	4.88 pixels for one arcsec slit
Slit width & length	Larger than 0.35 arcsec, any length and shape
Grisms	75 to 720 gr/mm rulings
Dispersions	6.3 Ang/pixel to 0.53 Ang/pixel
Resolutions	R = 180 to 2520 (1 arcsec slit)
Limiting magnitudes in 1h (Ag coated UT)	I = 24.1, 5sigma, R ~ 200; I = 22.7, 5sigma, R ~ 2500

Configuration	Input fiber selection, special masks in place
Field	1' x 1' and 24" x 24"
Design	6400 microlenses coupled to fibers, fibers coupled to 4 output long slits per channel
Wavelength range	3700 to 10000 Angs (Silica microlens array)
Spectral resolution	Same as for MOS with 1" equivalent slit

Design Assembly	Design View
Optics
Opto-Mechanical Layout
Mechanical Sub-Systems
Integral Field Unit
Co-rotator

Integration hall at OHP, France
Instrument
Optics
Grisms Filters	Grism data and curves, Grism dimensions Filters data and curves
Structure
Mechanical sub-assemblies
Integral Field Unit
IFU, mask modules
Detectors, see also ESO optical detector team
Test Tools