VLT Multi-Object Spectroscopy
26 arcmin. diameter image of the AXAF deep field
Oz-Poz, the multi-fibre positioner of the FLAMES facility which is installed at one Nasmyth focus of MELIPAL, accesses this whole field of view. It feeds the GIRAFFE spectrograph with light from up to 130 different objects and the UVES spectrograph with up to 8 objects.
In multi-slit spectrographs, short slits are either mechanically positioned (FORS1/2) or cut by a laser drill into a mask (FORS2, VIMOS), at the positions of the stars, nebulae or galaxies studied. The fields covered by these instruments are overlayed on the AXAF field.
Please click on an instrument name in the following list to get an enlarged image of its field with the slits superimposed:
- 19 for FORS1
- 75 for FORS2
- 750 for VIMOS
- GIRAFFE shows a small subset of the 130 fibers on the sky.
- NIRMOS was cancelled.
Now that this large multiplex capability is in full operation, the VLT will produce hundreds of thousands of spectra per year.