The Italian Theoretical Virtual Observatory (ITVO) is an ongoing project with the goal of creating a distributed archive of data coming from numerical simulations. It is fully involved into the International Virtual Observatory Alliance (IVOA) standardization process to meet the requirements of theoretical (or simulated) data.

The data archive presently consists of the outcome of a set of high and cosmological simulations run with the three popular codes:

• Gadget-2 (http://www.mpa-garching.mpg.de/galform/gadget/index.shtml) ;
• Enzo (http://www.cosmos.ucsd.edu/enzo/);
• FLY (http://www.oact.inaf.it/fly/ )

ITVO@Trieste

ITVO@Trieste:

The data archive presently consists of the outcome of a set of high end cosmological simulations run with the two popular codes Gadget-2 (http://www.mpa-garching.mpg.de/galform/gadget/index.shtml) and Enzo (http://www.cosmos.ucsd.edu/enzo/).

Credits/acknowledgements:

You are welcome to use the simulation data in these pages for your own scientific purposes. If you use the data in a publication or proposal please cite:

1. Borgani S. et al., 2004, MNRAS 348, 1078-1096,
   if you use Gadget-2 output or post-proccessing files;
2. S. Ameglio et al. 2007, MNRAS 382..397A
   if you use galaxy clusters maps and/or profiles;
3. Gardini et al. 2004, MNRAS, 351, 505 and Rasia E. et al. 2007 2008, ApJ,674, 728
   if you use X-MAS output file of Level3;
4. we would appreciate inclusion of the following sentence in the `Acknowledgements' section of papers which make significant use of our databases: "The ITVO@Trieste databases used in this paper and the web application providing online access to them were constructed as part of the activities of the Italian Theoretical Virtual Observatory." and/or cite:
5. Manzato P. et al., 2007, proceedings EFMCSC series World Scientific.
6. The archive and tools of the web portal are described in:
   Manzato et al. 2008, Astronomical Data Analysis Software and Systems XVII, ASP Conference Series, Vol. XXX, J. Lewis, R. Argyle, P. Bunclarck, D. Evans and E. Gonzales-Solares, eds.

ITVO@Trieste data description:

The architecture of the database is characterized by multilevels of metadata which contain:

1. Level 0 : the metadata of the direct outcome of the simulation, like the description of the algorithm, the computational and cosmological parameters, the code used to make the running, the redshift , the box size of the direct output files of simulation in HDF5 (Hierarchical Data Format )format for Enzo outcame or Gaget format for Gadget-2 outcome, this last one have the output divided in 16 files named lcdmg_be_gd2_192_480_xxx where xxx is the snapshot number (the interface is under development);
2. Level 1: cutout of Gadget raw data with an identification of interesting objects, at this moment there are the galaxy clusters and groups identified at many redshift , see Borgani et al. 2003 (this web interface is under development), in particular there are 1986 galaxy clusters, about 117 boxes at 17 different redshifts in which you can find these calculated quantities:

   POS	Positions
   VEL	Velocities
   ID	Particle ID's
   MASS	Masses (only for certain particles)
   U	Internal energy (only SPH particles)
   RHO	Density (only SPH particles)
   NE	Electron density (only SPH particles, and only if cooling is enable)
   NH	Neutral hydrogen density (only SPH particles, and only if cooling is enable)
   HSML	SPH smoothing length h (only SPH particles)
   SFR	Star formation rate of SPH particles (only for star formation )
   AGE	Formation time of star particles (only for star formation and STELLARAGE)
   Z	Metallicity of gas and star particles (only for star formation and METALLICITY)

3. Level 2: post-processing of Gadget data in particular a user can download 2-D maps for the density, the spectroscopic-like temperature, the mass-weighted temperature, the Sunyaev-Zel’dovich emission and the X bolometric luminosityin 0.5-2 (10^44erg/s) band and create on-the fly the graphic of the profiles for the density, the spectroscopic-like temperature, the mass-weighted temperature and emission weighted temperature for 117 galaxy clusters and groups at redshift 0.0 (at the moment you can’t view the VOTable, the preview is under development). A C code written by S. Ameglio and now modified by us create on-the-fly a FITS BINTABLE of ten quantities.
4. Level 3 : is the last level of post processing of Gadget data where are stored the output files of X-MAS a code for simulating the Chandra ACIS instrument, at the moment are stored 164 files at redshift near 0 with a mass cut at 1E14 Msun/h:
   INSTRUMENT= CHANDRA ACIS
   EXPOSURE TIME = 200 ksec
   F.O.V.= 16 arcmin
   Z(metallicity) = 0.3 Zsun
   nH(galactic absorption) = 5. 1E-20
   REDSHIFT : ranging between 0.06 and 0.15 modified in order to have R_500 inside the F.O.V.
   For the list of redshift used, the ARF and RMF files used, please, email to E.Rasia

The data of the level 2 are also accessable by a new feature create in the Aladin tool. The Aladin jar file is downloadable here from CDS website http://aladin.u-strasbg.fr/java/nph-aladin.pl?frame=downloading and than you have to download a txt file ITVO.txt for adding the ITVO menu and at the end lunching the Aladin.jar file using the command:

java -jar Aladin.jar -glufile=ITVO.txt

Aladin is a tool written by CDS, Strasbourg, France in which you can find the menu item ITVO (at the moment there are work in progress!!! ).