VIMOS Documentation

In this page, you will find all the manuals needed to prepare and analyze your observations with VIMOS.
Please be sure to download the version corresponding to the period in which the observations will take place.

All the manuals are in Adobe's Acrobat format.

VIMOS User's Manual

All the information about the instrument itself, its modes and their characteristics as well as the informations on the acquisition, observation and nighttime calibrations templates.

VIMOS will be decommissioned at the end of Period 100 or early in Period 101, and is therefore not offered in Period 101.

  • Version 101. Includes colour transformations between the VIMOS IMG filter system and the APASS system used in the UK in-kind reprocessing of archival imaging data.
  • Period 100, for P100 phase 1 and 2. No changes wrt P98.
  • Period 99, for P99 phase 1 and 2. No changes wrt P98.
  • Period 98, for P98 phase 1 and 2. Added a warning regarding absorption features in the MR-GG475 setting.
  • Period 97, for P97 phase 1 and 2
  • Period 96, for P96 phase 2. Added information on unified GuideCAM/Pilmos tool.
  • Period 96, for P96 phase 1. Added information on IFU skyflats for HR_blue grism.
  • Period 95, for P95 phase 2. Note the update regarding the rules for attached MOS nighttime calibrations (Sect. 3.5.8.), based on the analysis in Wolff et al. (2014) as summarised further down on this page.
  • Period 95, for P95 phase 1. Note the change about pre-imaging: to be done as loose OBs, not in concatenations.
  • Period 94, for P94 phase 2. Note one change relevant for Phase 2: users are requested to specify standard star requirements for pre-imaging.
  • Period 94, for P94 phase 1 (no change since P92)
  • Period 93, for P93 phase 1 and 2 (no change since P92)
  • Period 92, for P92 phase 1 and 2
  • Period 91, for P91 phase 1 and 2
  • Period 90, for P90 phase 1 and 2
  • Period 89, for P89 phase 1 and 2
  • Older Manuals

VIMOS GuideCam Tool User Manual

The Phase 2 Proposal Preparation Tool - P2PP3

Starting in P90 the preparation of OBs for VIMOS requires P2PP3. New concepts of scheduling containers such as time links and concatenations have been included in P2PP version 3 tool.

Video tutorials and practical examples how to prepare survey OBs can be found on the following page:

VIMOS Pipeline User Manual

The VIMOS pipelines, manuals, and static calibration database can be found here.


Wavelength accuracy without attached MOS calibrations (P95 onwards)

In the following memo Wolff et al. (2014) we investigate the accuracy in wavelength calibration that can be achieved when skipping the attached MOS nighttime calibrations, and thus calibrating nighttime observations with daytime calibrations only. We find that for grisms LR_blue, LR_red, HR_red, the wavelength accuracy is about 0.5-1.0 pixel, whereas it degrades to 1.0-2.0 pixel accuracy for grisms HR_blue, MR, and HR_orange. This is caused by residual flexure effects that cannot be fully corrected with the current Active Flexure Compensation mechanism. Internal accuracy not considering flexure effects are of order 0.3 pixels.

As a consequence, rules in P2PP for attached MOS calibrations have been updated for P95: for the more accurate grisms LR_blue, LR_red and HR_red (<1 pixel) the previously implemented waivable error has been converted to a warning. That is, users can create their MOS OBs without attached calibrations, but need to check that their science case can accept wavelength accuracies of 0.5-1.0 pixels. For the less accurate grisms HR_Blue, MR, and HR_orange the waivable error remains in place.

  • Wolff et al. (2014) memo on the accuracy in wavelength calibration that can be achieved when skipping the attached MOS nighttime calibrations.

Data reduction frequently asked questions

A list of Frequently Asked Questions on data reduction can be found at: