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Facilities and Instruments Description framework

Describing Facilities, Telescopes and Instruments

This is a common effort initiated in the Semantics working group, namely with suggestions from Planetary science services at Paris Obseervatory and collaborators.

The idea is to identify and gather needs for a homogeneized description and identification of instruments, telescopes, space missions, space crafts, etc. and create a maintained repository of identifiers re-usable by the community for

- keywords verifications in data sets serialisation

- data citation

- facilicity citations tracing

etc...

Context: "science questions drive the need for multi-lambda, multi-messenger observations" (Mark Allen, HCERES). Discoverability of observations would be improved.

Existing Initiatives

ExistingInit

UseCases

Use Cases for Facilities description

Discussion for a description schema

from the usage exposed , we see the facilities and instruments need to be standardized (name , ids ) together with physical features such as spectral range, operational period, field of view, spatial resolution, mode, etc.

Nominal feature values for instruments can be used in various services, when the information attached to a dataset ( associated data , catalog , etc) is not available).

Use cases exposed above may have 3 levels of usage for instruments/ telecope parameters:

  • precise : theses are the exact parameters for a specific observation
  • intermediate: the usual values ex spectral coverage , recorded for a data collection ( ex 2MASS J --> fits the range of filter J.
    This applies when fluxes have been converted to a different photometric system than the original instrumental one
  • global : when no other info is provided for the spectral range of a data set, the min and max spectral range of the instrument can be used.

Missions/ Telescopes X

                                                                
        -----------------------------------------------------------------------------------------------> 
        1978 1981 1883  1986 1990  1993  1995 1996    1999  2001  2002   2004                        2011
        Einstein   EXOSAT     |      |            Beppo SAX('96-'02) |     SWIFT (2004-ongoing?)       
                             BBXRT   |                               INTEGRAL(2002-ongoing)               
                              |      |-----------------------|
                              |             ASCA(1993-2001)          
                              |            |----------------------------------------------------------|
                              |                                RXTE(1995-2011)    
                              |-----------------------|
                                  Rosat (1990-1999)   |
                                                      Chandra(1999-ongoing)
                                                      XMM-Netwon : EPIC, MOS/PM, RGS (1999-ongoing)                     

Example of Mihaela schema for observation dates of X-ray missions.

She made the same kind of diagram for the wavelengths:

                                                      
             3000A    4000A    5000A    6000A    7000A    8000A    9000A    10000A
             300nm    400nm    500nm    600nm    700nm    800nm    900nm    1Ám     1.2Ám      1.6Ám     2.1Ám                                         
             ---------------------------------------------------------------------------------------------------------> 
                 U u      g B        V       r R       i I          z                J          H         K         filtres Simbad
                          B=F435W    V=F555W r=F625W   i=F775W      z=F850LP         J=F110W    H=F160W             filtres HST
                          g=F475W                      I=F814W                                                      filtres HST
           ___________________________                                   ____________________________________                                              
                                      |                                 |
                                      |                                 |
             0.01nm    10nm      380nm(3800A)    700nm(7000A)   1Ám   2.5Ám  30Ám  300Ám  1mm/300GHz   1cm/30GHz    1m/ 300MHz       longueur d'onde                                               
        --------|--------|----------|----------------------------|-------|-----|-----|---------|-----------|---------|----------------> 
         Gam         X        UV             Opt                    NIR    MIR   FIR     smm        mm      micro-onde                                            
                                                                                                            -------------Rad----> 

It shows that by having a centralised description of telescopes/instruments and the physical features of spectral range or operationnal periods, the discoverability of specific observations is facilitated.

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Topic revision: r11 - 2017-02-22 - EmmanuellePerret
 
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