The names of all pipeline products follow a certain naming convention. This is done to have human-readable rather than technical file names. The naming scheme has been chosen to have the type of product, its date of creation, and its pipeline-relevant parameter values all recognizable from the product name.

Since the begin of period 75 (April 2005), both science and calibration product files are renamed. (Actually, there was a transition phase extending for some instruments from April towards the end of the year 2005).

Before that date only calibration products followed the common scheme which is described here. (Some instruments had their own naming scheme which is described below, if applicable).

The general format of user-oriented product file names is the same for all VLT/VLTI instruments.

Instrument code

All pipeline product names start with two letters which are specific for the instrument. For instance: UVES product names start with 'UV', VISIR names with 'VR'.

Type of product

Next, the product type is coded. The full value is coded in the fits header key HIERARCH.ESO.PRO.CATG. A short form of this tag is coded in four characters being unique per instrument:

1st letter M or P calibration product   S science product   G general calibration product (as of P82) 2nd to 4th letter ... type of product

top MIDI

All MIDI products start with MI_. Not all products listed below are delivered to the users, as some are needed only during early steps of the calibration cascade (i.e. not for the processing of science data) or even only needed for quality checks.

top SCIENCE PRODUCTS

Science products have the following scheme:
MI_S<PPP>_<OBS_ID>_<DATE_TIME>_<parameter_string>.<ext> (e.g. MI_SHSS_224715_2006-04-15T05:34:56.000_U1U4_HD135344P.fits)
where:

• S<PPP> is the four letter code uniquely describing the type of SCIENCE product (the first letter is always S for SCIENCE)
• <OBS_ID> is the OB number read from the OBS.ID fits key
• <date_time> is the UT date and time of the first raw frame measured for the OB (e.g. 2005-04-01T04:31:12); this information is required since OBs can be executed several times
• <S1><S2> are the telescope stations (e.g. A1J3)
• <target> is the target name, e.g. hd0953
• <disp> is the dispersion, e.g. P(rism) or G(rism)

where:
<S1><S2> are the telescope stations (e.g. A1J3)
<target> is the target name (e.g hd9053)
<dataset> refers to the teelscope producing the image (d1/d2 for telescope 1/telescope 2)
<disp> gives the dispersive element (OPen/GRism/PRism)
<tel> gives the status of the beams ABOPen/CLOSED