Metadata for publication in GAVO's Data Center
==============================================

To make your data visible to other astronomers and the general public,
the umbrella organization of the VO, the IVOA_, runs a registry of
services.  To feed it meaningful data, and also to enable users of your
service to find out whose data they are using, we ask you to provide
data as specified below (and, of course, as applicable).  You are most
welcome to get back to us if you have questions.

The italicized text in the explanations is taken from [RMI]_.

:Title:
  A short phrase (preferably less than 6 words) giving people an idea
  what the service is about.  This will be the title and the headline on
  forms, etc.  *Title should be an unabbreviated form (e.g., Hubble
  Space Telescope) rather than an acronym unless the acronym is so well
  known as to be part of standard usage.*

:Short Name:
  This should be an abbreviation of less than 16 characters.  If you
  can't think of anything sensible, don't worry, we'll make one up for
  you.  *The ShortName will be used where brief annotations for the
  resource name are desired, such as in GUIs that might refer to many
  resources in a compact display. [...] ShortName strings are limited to
  a maximum of sixteen characters.  Care should be taken to define
  illuminating ShortNames indicating either where the resource comes
  from or what data collection it provides.  ShortNames are not required
  to be unique.  Indeed, a resource provider may use the same ShortName
  for several related resources (e.g., different services that access
  the same collection), or the same ShortName might be used by different
  providers for common/mirrored resources.*


:Creator Name:
  Well, your name and the names of your collaborators.  If you have a
  logo, be sure to pass it to us.  Some GUIs display logos in their
  result listings, and that increases visiblity dramatically...
  *An entity primarily responsible for making the content of the resource.
  Examples of a Creator include a person or an organisation.  Users of
  the resource should include Creator in subsequent credits and
  acknowledgments. [..] If the resource is a data collection or service
  accessing a collection, then Creator fields should list the scientists
  responsible for the original data collection.  Typically, this would
  be list of authors associated with the defining published paper for
  the collection. [...] Full names should be given, not just surnames.*

:Version:
  Optional. If you think you will make "data releases" and old "releases" might be
  required to stick around, giving a version is a good idea.  In those
  cases, you should talk to us, since we might need to plan how old
  releases might be kept.  For most cases, we believe this versioning
  adds largely unnecessary overhead (until a service is very
  successful and in some way changes behaviour, that is).

:Subjects:
  *A list of the topics, object types, or other descriptive keywords
  about the resource. [...] To support keyword-based searches of
  registry contents, the Subject element should be as specific as
  possible and include as many relevant terms as possible.* If at all
  possible, the subjects should come from a controlled vocabulary.  We
  recommend you first check the `IVOA Vocabulary Explorer`_, but
  both `Astronomy Journal Keywords`_ and `Vizier Keywords`_ will do fine
  if you already have those.

:Description:
  *Thorough text descriptions are particularly encouraged in order to
  make text-based searches against the registries maximally useful.
  Description should emphasize what the resource is about, as other
  matters such as who created it, when it was created, and where it is
  located are described elsewhere in the resource metadata.*   This
  should not be a complete article, but *at most* something like an
  abstract.  In general, we feel a few lines would be optimal here.
  For anything more, we can include a "long documentation" that will
  be exposed in the service info.  Please write in the third person
  (i.e., "Fantasurvey is..." rather than "We present the fantasurvey...")

:Source:
  Optional. Some paper describing what you did to arrive at your data, if you
  already have published one.  Preferable, we'd like to see a bibcode
  here.  For online publications, use referenceURL.

:Reference URL:
  If you have substantial amounts of documentation on your data, you
  should provide a URL to that document here.  You're welcome to host
  these documents at our data center (where, we hope, it might be
  longer-lived than on some private web page, for example).  If you
  don't give us a reference URL, the DC software will insert the URL of
  the query page, which is usually not what you want.

:Facility:
  Optional.  *The observatory or facility where the data was obtained.
  Some resources are likely to hold data from multiple observatories.
  If just a few, this could be a list; if very many, just say "many".
  Theoretical data will not originate with an observatory, but rather
  might be characterized by the computational facility used to create
  them (NCSA, SDSC, etc.).  Facility should be used only to describe
  entities that specifically produce or manage data.  Observatory names
  are the most common values.*  Actually, facilities can receive
  identifiers that in turn makes more information about a facility
  accessible within the VO.  GAVO can give you such an identifier if you
  want.
  
:Instrument:
  Optional. *Can be a specific instrument name (Wide Field/Planetary
  Camera 2) or generic instrument type (CCD camera).  Theoretical data
  is produced by a computer code, and the name of the code could be
  specified.*

:Coverage:
  Optional.  This is supposed to reflect what part of the sky, the
  electromagnetic spectrum, etc., the data is talking about.  If you
  feel you want to specify coverage, talk to us; the topic is too
  complicated to discuss here.

:Copyright information:
  If you have any special wishes ("if you use..., please
  acknowledge..."), or if you want to restrict what people can do with
  your data, this would go here.  GAVO offers "embargoed" publication
  where, for a limited time, only persons having a password can access
  data files or a service.  If this is interesting for you, talk to us.

:Service profile:
  Certain VO protocols have a notion of "verbosity", giving more or less
  fields depending on the query.  For data giving enough columns, it
  would be nice if you gave us your assessment of the "importance" of a
  column, going from 1 (most important, data is worthless without this
  column) to 30 (only very specific and exotic applications will need
  this column).
  

Other issues
------------

If you have data "with positions" (i.e., your data will be published
using the Simple Cone Search (SCS) protocol), a unique identifier
for each table row is required.  While a row counter will do fine, you
will probably do yourself a favour if you follow the IAU conventions
([IAU]_).

If you have any wishes concerning the appearance of your service (on the
Web or within the VO), just let us know.  We can do a lot of
customization and even if we can't, we'd still like to know about them.


.. _Astronomy Journal Keywords: http://www.aanda.org/index2.php?option=com_content&task=view&id=170&Itemid=184
.. _IVOA: http://www.ivoa.net
.. _IVOA Vocabulary Explorer: http://explicator.dcs.gla.ac.uk/WebVocabularyExplorer/
.. _Vizier Keywords: http://vizier.u-strasbg.fr/doc/ADCkwds.htx


Bibliography
------------

.. [RMI]  Hanisch, R., et al, "Resource Metadata for the Virtual
   Observatory", http://www.ivoa.net/Documents/latest/RM.html

.. [IAU] IAU Commission 5, "Specifications concerning designations for
   astronomical radiation sources outside the solar system",
   http://cdsweb.u-strasbg.fr/Dic/iau-spec.html