SSA-1.1

[Petr Skoda]

> TARGETNAME is an important feature for some new things we want to do
> (e.g. SEDs), however it is not needed for the usual spectrum searches
> and is rarely implemented by services.

Yes - it is a reason I think we should suggest even for "usual searches"
Maybe I was not clear enough in my mail:
Hence the summary is:

1) There are objects you can easily find only if using TARGETNAME query
   You cannot find easily their coordinates in common name resolvers

2) If the service does not provide TARGETNAME search, you have to bother 
to enter coordinates manually in current VO tools - which is extremely 
bothering (including the conversion to dec degrees)

3) Still you cannot select precisely the spectrum you want as the 
coordinates given are not precise enough - e.g. high proper motion star,
spectra extracted from different stars on slit while pointing to the same 
place

4) You cannot get spectra of solar light reflected from e.g. minor planets 
- commonly used for calibrating echelle spectra EW (e.g. ELODIE 
calibration on Vesta) or just sky spectrum taken early morning.. And there 
is no need to make TARGETNAME mandatory (as it is not the service handling 
solar system objects in most cases)

5) You cannot publish spectra of Planet harboring star if the PI requires 
to wipe out coordinates and/or time information - but the spectrum itself 
is not "harmful" - common problem in ELODIE archive.

The reason, why there are not services supporting TARGETNAME is simple - 
we have very few SSA spectra archives and the necessity of provide 
coordinates may prevents providers  to include all really processed 
spectra due to the above mentioned problems.

I hope this will change soon and IMHO the standard should be here already 
to provide the strict rules how to do it.
I am pretty sure that the current providers of spectra (e.g. CADC serving 
spectra from CHFT instruments, French community behind NARVAL etc ...) 
will face the above problems immediately after looking in their archives 
and FITS headers ;-)


  We also need more experience to 
> learn how to use this effectively so I don't see this as an issue
> which needs to hold up SSA 1.1.

I do not see reason for holding up release of SSA too long. If there are 
no services we cannot break any ;-)
So just adding the sentence about the format of the name - including the 
recommended wildcard schema could be done quickly - I am not just strong 
in URL enconding so I wanted to ask the experienced community.

> What we are finding for SEDs is that TARGETNAME wants to be mandatory

I would be happy if we could rise the TARGETNAME to REC status for all 
services - but here I feel some problem with accepting this on existing 
services.

> as name resolution has usually already been performed for SEDs since
> they combine data from multiple observations, often of well known
> sources,
well but you have to collect the parts first which may involve the same 
problems (look for specific catalog - e.g. the satellite target list and 
enter the coordinates manually or as a input list.

> and searches for SEDs are normally performed by object name.
> Hence this will give us an opportunity to gain more experience with use
> of this parameter for non-planetary data.  (This is one example
> BTW of how SEDs and SSA/spectrum can differ).

I do not see any difference - simply the taget name is an (almost) unique
identifier of any object - I can be interested in SED of star KEPLER 
xxxxxx in a archive without knowing the identity of a star (real example - 
the observer only gets coordinates from the PI) and while writting the 
FITS the OBJECT is filled naturally with such weird name.
Does not matter whether it is photometry point or spectrum ....

>
> Rather than make SSA more complicated than it is I think we should gain
> some more experience with SEDs and time series as compared to spectra,

I am afraid that it may take a long time before working SED services 
(using the Photometry DM ) will apear. But there is a lot of people asking 
for practical rules how to publish spectra from pointed observations as 
the VO-awareness is rising in astronomical community.

> to see what features/capabilities are most important for each class of
> data, closely related as they may be.

I think that ask for name using some wildcards is a most natural thing 
everyone understands (thanks to google ;-)

Cheers,

Petr

*************************************************************************
*  Petr Skoda                         Phone : +420-323-649201, ext. 361 *
*  Stellar Department                         +420-323-620361           *
*  Astronomical Institute AS CR       Fax   : +420-323-620250           *
*  251 65 Ondrejov                    e-mail: skoda at sunstel.asu.cas.cz  *
*  Czech Republic                                                       *
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