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VIMOS
VIMOS PIPELINE: SCIENCE REDUCTION
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The VIMOS pipeline is designed to reduce raw science data
On Paranal, the quick-look pipeline makes an attempt to automatically
reduce all science data. The reduction
is performed using standard calibration products from a local
calibration database and using, for MOS, the distorsion models written in the science frames header.
At QC Garching, IMAGING, MOS and IFU SCIENCE data taken in Service Mode are
pipeline-reduced, using the best available calibration solutions
(quality-checked and closest in time, following the calibration cascade).. For imaging the data reduction is pipeline supported for all filters. For spectroscopy the pipeline reduction is supported for the following GRISM + Order Sorting Filter combinations:
- LR_red + OS-red
- LR_blue + OS-blue
- MR + GG475
- HR_orange + GG435
- HR_red + GG475
- HR_blue + None
The reduction of Bezier slits is not pipeline supported.
The products of science reduction are also quality-checked.
If any irregularity in the reduced data is found, an attempt
is made to improve on this. If not possible, information about
the poor quality is made available in the SM package. A list of the typical reduction problems found is given in the ServiceMode
page.
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| TYPES
OF RAW SCIENCE DATA |
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| FITS headers |
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frame
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.txt
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SCIENCE IMAGE
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SCIENCE MOS
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| SCIENCE IFU |
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The following types of raw science data exist for the VIMOS
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DPR TYPE |
template |
comment
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| IMAGE |
OBJECT |
VIMOS_img_obs_Offset |
stare and jitter mode (jitter mode is not pipeline supported) |
| MOS |
OBJECT |
VIMOS_mos_obs_Offset |
stare and jitter mode
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| IFU |
OBJECT |
VIMOS_ifu_obs_Offset |
stare and jitter mode (jitter mode is not pipeline supported) |
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| IMAGE |
SLIT,OBJECT |
VIMOS_mos_acq_Mask |
acquisition frames for MOS |
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![[top]](../img/arr1red-up.gif) |
SCIENCE
PRODUCTS |
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Recipes and products
The following VIMOS raw science files are used to create
science products (click here
for a complete overview of science products and reduction recipes):
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frame(s) |
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recipe
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description |
product(s)
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IMAGE
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![[imgsci.gif 3K]](../img/imgsci.gif) |
vmImObs
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reduce single images and jitter stacks |
<prod>.fits, <,
<prod>.tfits, <prod>.log
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| MOS
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![[mosscirawLR_blue.gif 14K]](../img/mosscirawLR_blue.gif) |
vmMosObs
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reduce MOS single images and jitter stack |
3x <prod>.fits, 2x <prod>.tfits,
<prod>.log
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| IFU
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![[ifusciraw.gif 14K]](../img/ifusciraw.gif) |
vmifuscience
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reduce IFU single images |
2x <prod>.fits, <prod>.log
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Association rules
For the reduction of science data calibration products are
required. The selection of appropriate calibration products follows the
association rules.
Naming scheme
The reduced science products have the same name of the raw
file (or the first of the raw files) with the prefix "r.". If the products are more than one they are
numbered in successive order. Tables have the suffix ".tfits", images ".fits".
As an example: the reduction recipe for the raw MOS science frame VIMOS.2002-12-19T03:48:24.648.fits,
produces 5 products, 3 images and 2 table called: r.VIMOS.2002-12-19T03:48:24.648_0000.fits
r.VIMOS.2002-12-19T03:48:24.648_0001.fits
r.VIMOS.2002-12-19T03:48:24.648_0002.fits
r.VIMOS.2002-12-19T03:48:24.648_0003.tfits
r.VIMOS.2002-12-19T03:48:24.648_0004.tfits
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![[top]](../img/arr1red-up.gif) |
REDUCTION
CASCADE |
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The successful execution of science reduction requires a complete set of calibration products available. All science data processed by QC Garching are reduced with a quality-checked set of calibration files which are usually generated from daytime calibrations
taken immediately after the science night and produced following the calibration cascade.
All science products created by QC Garching follow the reduction
cascade.
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![[top]](../img/arr1red-up.gif) |
ACTUAL
PROBLEMS AND ISSUES |
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VIMOS Pipeline problems
are documented under on the ServiceMode
page. |