Theoretical Data UCD Proposal

[Franck Le Petit]

	Dear Marco, and Gerard,

	This summer with Fabrice Roy and the help of Miguel Cervino we began  
to have a look for semantics for Theory.
	As suggested by Gerard, we should coordinate this effort together.  
Unfortunatly I will be very busy up to mid-november. But after that,  
I think we should definitively try to advance on this problem with  
Fabrice and Miguel.

	Best regards
	Franck


Le 22 oct. 07 à 11:17, Gerard a écrit :

> Dear Marco
>
> Would it be possible for you to organize this work together with  
> Franck Le
> Petit, who is leading a corresponding effort within the theory  
> interest
> group?
>
> Thanks
>
> Gerard Lemson
>
>
>> -----Original Message-----
>> From: owner-theory at eso.org [mailto:owner-theory at eso.org] On Behalf Of
>> Marco Molinaro
>> Sent: Monday, October 22, 2007 10:54 AM
>> To: semantics at ivoa.net; theory at ivoa.net; andrea.preitemartinez at iasf-
>> roma.inaf.it
>> Subject: Theoretical Data UCD Proposal
>>
>> Dear all,
>> we want to start writing down a list of quantities for theoretical  
>> data
>> and then propose these quantities for inclusion into the UCD1+
>> controlled vocabulary.
>> The ITVO group works on cosmological simulations and stellar  
>> evolution
>> models. As a first step these notes notes are dealing with  
>> cosmological
>> quantities.
>> The underlying idea is to contribute to the
>>
>> http://www.ivoa.net/twiki/bin/view/IVOA/IVOATheoryGeneralRequirements
>>
>> discussion and, at the same time, suggest some ucds for simulated  
>> data.
>> We opened a wiki page where everyone can add missing quantities and
>> related ucds
>>
>> http://www.ivoa.net/twiki/bin/view/IVOA/TheoreticalDataUCDProposal
>>
>> We feel the absence of the cosmological parameters' ucds, like:
>>
>> H, H0 - Hubble parameter, constant
>> all the 'omega' parameters (matter, baryon, lambda, ...)
>> sigma8, spectrum-normalization parameter.
>> ...
>>
>> For all of these we are, at present, using the not-so-descriptive
>> src.morph.param;phys.cosmology ucd compound and this is a problem
>> because cosmological simulations make large use of these  
>> parameters for
>> their description.
>> Maybe another important parameter to add is the expansion factor  
>> which
>> pairs the cosmological redshift (for this last the ucd already  
>> exists).
>>
>> Other ucds we want to add (or ask attention for) are related to the
>> 'temperatures' used, for example in galaxy clusters simulations. we
>> think a good idea is to add ucds like
>>
>> phys.temperature.emissionweighted
>> phys.temperature.massweighted
>> phys.temperature.speclike
>>
>> following the idea of the existing .effective and .electron ones.
>> Another ucd, or ucd group, could be related with the 'critical  
>> density'
>> radius, adding the simple phys.radius.rhocritic and/or its  
>> extensions to
>> phys.radius.rhocritic.NNN (namely NNN=200, 500, 2500).
>> Maybe another choice for this problem could be something like
>> phys.size.radius;phys.cosmology.rhocritic
>> which is better if one wants to relate the critical density to other
>> quantities than the radius (let's say:
>> phys.temperature.speclike;phys.cosmology.rhocritic)
>>
>> To simplify all these ucds an idea could be adding a new category, to
>> the already existing 12, named 'cosm' to replace the phys.cosmology
>> which is an 'S' word. But I don't know if the resulting  
>> semplification
>> in the single ucds is a sufficient gain compared to adding a  
>> categorie
>> in the UCD schema.
>>
>> We also want to add other ucds like:
>> - 'object.gas', 'object.stellar', 'object.darkmatter', ...and so  
>> on, as
>> 'S' words to specify which masses, temperatures or other  
>> quantities we
>> are talking of
>> - a ucd for the cosmological model of the simulation
>> - a ucd for the code used in the simulation
>> - a ucd for the linear size of the simulated cosmological box
>>
>> Together with these proposed ucds we want to focus the attention  
>> of the
>> community on the ucds needed by the stellar simulations.
>>
>> Regards
>> 	Marco
>>
>> Marco Molinaro
>> INAF - Trieste Astronomical Observatory
>> Phone.: +39 040 3199 152
>> e-mail: molinaro at oats.inaf.it
>> web site: http://wwwas.oat.ts.astro.it/
>