- ID:
- ivo://ivoa.net/std/VODML
- Title:
- VO-DML: a consistent modeling language for IVOA data models
- Date:
- 31 May 2018 09:00:00
- Publisher:
- IVOA
- Description:
- This document defines a standard modelling language, or meta-model, for expressing data models in the IVOA. Adopting such a uniform language for all models allows these to be used in a homogeneous manner and allows a consistent definition of reuse of one model by another. The particular language defined here includes a consistent identification mechanism for model which allows these to be referenced in an explicit and uniform manner also from other contexts, in particular from othe IVOA standard formats such as VOTable. The language defined in this specification is named VO-DML (VO Data Modeling Language). VO-DML is a conceptual modeling language that is agnostic of serializations, or physical representations. This allows it to be designed to fit as many purposes as possible. VO-DML is directly based on UML, and can be seen as a particular representation of a UML2 Profile. VO-DML is restricted to describing static data structures and from UML it only uses a subset of the elements defined in its language for describing "Class Diagrams". Its concepts can be easily mapped to equivalent data modelling concepts in other representations such as relational databases, XML schemas and object-oriented computer languages. VO-DML has a representation as a simple XML dialect named VO-DML/XML that must be used to provide the formal representation of a VO-MDL data model. VO-DML/XML aims to be concise, explicit and easy to parse and use in code that needs to interpret annotated data sets. VO-DML as described in this document is an example of a domain specific modeling language, where the domain here is defined as the set of data and meta-data structures handled in the IVOA and Astronomy at large. VO-DML provides a custom representation of such a language and as a side effect allows the creation and use of standards compliant data models outside of the IVOA standards context.
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- ID:
- ivo://padc.obspm.planeto/meteor_showers/q/epn_core
- Title:
- VOEvent meteor shower service
- Short Name:
- Meteor Showers
- Date:
- 16 Jul 2024 13:55:03
- Publisher:
- Paris Astronomical Data Centre
- Description:
- The ephemeris were produced by simulating the ejection of meteoroids from the sunlit hemisphere of cometary nuclei, typically from 0 to 3 au, followed by the propagation of orbits of meteoroids in the Solar System, taking into account the gravity of the Sun, the 8 planets, Pluto, and the Moon, as well as the radiation pressure and the Poynting-Robertson drag. Note that asteroid parent bodies were considered as active (i.e. comet-like bodies) even if they are not active today. The showers are predicted when a planet enters a large enough set of meteoroids, at a distance less than typically 0.01 au. See Vaubaillon J., Colas F., Jorda L. 2005 A new method to predict meteor showers. I. Description of the model, Astronomy and Astrophysics, Volume 439/2 p.751-760, as well as: Vaubaillon J. 2017 A confidence index for forecasting of meteor showers, Planetary and Space Science, Volume 143 p.78-82
- ID:
- ivo://org.gavo.dc/registryrss/q/rss
- Title:
- VO Fresh: New Services in the VO RSS
- Short Name:
- vofresh_rss
- Date:
- 27 Dec 2024 08:31:12
- Publisher:
- The GAVO DC team
- Description:
- New entries in the `Virtual Observatory <http://www.ivoa.net>`_'s registry in RSS format; this service lets you use a common "news aggregator" to learn of services appearing in the VO in almost real time. The data is taken from the VO registry by querying for new records twice a day. New items are announced here for 30 days. To subscribe to this feed, point your browser/news aggregator to http://dc.g-vo.org/regrss. If you can configure your client's update frequency, for this feed it is sufficient to update every 12 hours -- it is only updated morining and afternoon UTC. New entries on this feed are also distributed `on the Fediverse`_. To get notifications of new VO services, subscribe to `gavo@astrodon.social`_. .. _gavo@astrodon.social: .. _on the Fediverse: https://astrodon.social/@gavo
23944. VO HPSL datacenter Registry
- ID:
- ivo://src.pas/__system__/services/registry
- Title:
- VO HPSL datacenter Registry
- Short Name:
- HPSL Reg
- Date:
- 30 Aug 2018 05:15:21
- Publisher:
- The staff at the VO HPSL datacenter
- Description:
- The publishing registry for the VO HPSL datacenter.
- ID:
- ivo://src.pas/tap
- Title:
- VO HPSL datacenter TAP service
- Short Name:
- HPSL TAP
- Date:
- 17 Aug 2018 11:20:10
- Publisher:
- Space Research Centre of Polish Academy of Sciences
- Description:
- The VO HPSL datacenter is TAP end point. The Table Access Protocol (TAP) lets you execute queries against our database tables, inspect various metadata, and upload your own data. It is thus the VO's premier way to access public data holdings. Tables exposed through this endpoint include: columns, groups, key_columns, keys, schemas, tables from the tap_schema schema, epn_core from the rwcalerts schema, epn_core from the lofar_jupiter_raw schema, main from the arihip schema, epn_core from the lofar_jupiter schema, epn_core from the ionosondes schema, epn_core from the rwc_alerts schema, epn_core from the planetmongo schema.
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/4329
- Title:
- Void galaxies in the nearby Universe
- Short Name:
- J/MNRAS/482/4329
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The main goal of this work is to form a large, deep and representative sample of dwarf galaxies residing in voids of the nearby Universe. The formed sample is the basement for the comprehensive mass study of the galaxy content, their evolutionary status, clustering and dynamics with respect to their counterparts residing in more typical, denser regions and for study of void small-scale substructures. We present 25 voids over the entire sky within 25Mpc from the Local Group. They are defined as groups of lumped empty spheres bounded by `luminous' galaxies with the absolute K-band magnitudes brighter than -22.0. The identified void regions include the Local Void and other known nearby voids. The nearest nine voids occupy a substantial part of the Local Volume. Of the total number of 6792 cataloged galaxies in the considered volume, 1354 objects fall into 25 nearby voids. Of this general void galaxy sample, we separate the sub-sample of 'inner' void galaxies, residing deeper in voids, with distances to the nearest luminous galaxy DNN>2.0Mpc. The 'inner' galaxy sample includes 1088 objects, mostly dwarfs with MB distribution peaked near -15.0 and extending down to -7.5mag. Of them, 195 fall in the Local Volume (space within R=11Mpc). We present the general statistical properties of this Nearby Void Galaxy sample and discuss the issues related to the sample content and the prospects of its use.
- ID:
- ivo://CDS.VizieR/J/MNRAS/464/666
- Title:
- Void Galaxy Survey, photometry and structure
- Short Name:
- J/MNRAS/464/666
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse photometry from deep B-band images of 59 void galaxies in the Void Galaxy Survey (VGS), together with their near-infrared 3.6{mu}m and 4.5{mu}m Spitzer photometry. The VGS galaxies constitute a sample of void galaxies that were selected by a geometric-topological procedure from the Sloan Digital Sky Survey Data Release 7 data release, and which populate the deep interior of voids. Our void galaxies span a range of absolute B-magnitude from M_B_=-15.5 to -20, while at the 3.6{mu}m band their magnitudes range from M_3.6_=-18 to -24. Their B-[3.6] colour and structural parameters indicate these are star-forming galaxies. A good reflection of the old stellar population, the near-infrared band photometry also provide a robust estimate of the stellar mass, which for the VGS galaxies we confirm to be smaller than 3x10^10^M_{sun}_. In terms of the structural parameters and morphology, our findings align with other studies in that our VGS galaxy sample consists mostly of small late-type galaxies. Most of them are similar to Sd-Sm galaxies, although a few are irregularly shaped galaxies. The sample even includes two early-type galaxies, one of which is an AGN. Their Sersic indices are nearly all smaller than n=2 in both bands and they also have small half-light radii. In all, we conclude that the principal impact of the void environment on the galaxies populating them mostly concerns their low stellar mass and small size.
- ID:
- ivo://org.gavo.dc/voidoi/q/ui
- Title:
- VOiDOI DOI registration web service
- Short Name:
- DOI registration
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This service lets VO data publishers assign Digital Object Identifiers to their services, greatly enhancing their citability. Since technically, the DOI references the registry record, this service can only be used on properly registered services.
- ID:
- ivo://CDS.VizieR/J/AJ/161/42
- Title:
- Volume-limited sample of cool dwarfs. I. L0-T8 dwarfs
- Short Name:
- J/AJ/161/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new volume-limited sample of L0-T8 dwarfs out to 25pc defined entirely by parallaxes, using our recent measurements from UKIRT/WFCAM along with Gaia DR2 and literature parallaxes. With 369 members, our sample is the largest parallax-defined volume-limited sample of L and T dwarfs to date, yielding the most precise space densities for such objects. We find the local L0-T8 dwarf population includes 5.5%{+/-}1.2% young objects (<~200Myr) and 2.6%{+/-}1.6% subdwarfs, as expected from recent studies favoring representative ages <~4Gyr for the ultracool field population. This is also the first volume-limited sample to comprehensively map the transition from L to T dwarfs (spectral types ~L8-T4). After removing binaries, we identify a previously unrecognized, statistically significant (>4.4{sigma}) gap ~0.5mag wide in (J-K)_MKO_ colors in the L/T transition, i.e., a lack of such objects in our volume-limited sample, implying a rapid phase of atmospheric evolution. In contrast, the most successful models of the L/T transition to date-the "hybrid" models of Saumon & Marley-predict a pileup of objects at the same colors where we find a deficit, demonstrating the challenge of modeling the atmospheres of cooling brown dwarfs. Our sample illustrates the insights to come from even larger parallax-selected samples from the upcoming Legacy Survey of Space and Time by the Vera Rubin Obsevatory.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/1416
- Title:
- Volume-limited sample of M7-M9.5 dwarfs <20pc
- Short Name:
- J/ApJ/705/1416
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In a volume-limited sample of 63 ultracool dwarfs of spectral type M7-M9.5, we have obtained high-resolution spectroscopy with UVES at the Very Large Telescope and HIRES at Keck Observatory. In this first paper we introduce our volume-complete sample from DENIS and 2MASS targets, and we derive radial velocities and space motion. Kinematics of our sample are consistent with the stars being predominantly members of the young disk. The kinematic age of the sample is 3.1Gyr. We find that six of our targets show strong Li lines implying that they are brown dwarfs younger than several hundred million years. Five of the young brown dwarfs were unrecognized before. Comparing the fraction of Li detections to later spectral types, we see a hint of an unexpected local maximum of this fraction at spectral type M9. It is not yet clear whether this maximum is due to insufficient statistics, or to a combination of physical effects including spectral appearance of young brown dwarfs, Li line formation, and the star formation rate at low masses.
