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About Project


The COCOS database provide access to the data from a series of cosmological numerical simulations dubbed collectively as the Copernicus Complexio. The main purpose is to allow general audience and researchers fro mall-around the world to access this big cosmological data resource. Modern cosmological simulations consists of Terabytes of various heterogeneous data sets. It is not only not-practical but also infeasible to provide every interested researcher with their own copy of the simulation data. On the other hand modern big cosmological simulation provide essential data for many different science projects. Hence it is vital to provide as broad as possible audience with means allowing them to access the simulation data efficiently. In the past decade we have seen that this direction has been intensively developed in the community. The first pioneering data-base on this frontier was the famous Millennium Run Database, (hereafter MRD, established around 2004), which set out the standards and directions for the community for years to come. The great popularity and success of the MRD inspired other projects to follow. Next big cosmological database that was established in the past few recent years was the CosmoSim, which now contains the data from Multidark, Bolshoi and CLUES projects.

The designed purpose and functionality of the COCOS database are following the line outlined by these two successful projects. Here we are providing large data from the new class of cosmological simulations. The data is accessible via query engine that is compatible with easy to learn Structure Query Language SQL Structure Query Language SQL, but at the same time is based on modern fast and flexible Cloudera Impala SQL querry engine and Apache Hadoop database server.

The full database is accessible after proper registration. You can start immediately testing the database and construct test queries by using the TOY-SIMULATION, which is accessible without registration. For quick-start you might be also interested in Example Queries and Manual we have prepared.

You will find detailed information about the simulations and the database inventory and database model&structure in the documentation.

Copyrights and credits

This database is hosted and developed by ICM of University of Warsaw. The data is released under Creative Commons Licence CC BY-NC 4.0.

If you use the data please refer to these articles/resources:

Copernicus complexio simulations

The Copernicus Complexio (from Latin the Copernicus Conundrum; hereafter COCO), consists of a series of DM-only simulations tailored for the study of a statistically significant sample of well resolved Milky Way-size haloes and their satellites. The project was conducted in cooperation and collaboration between the ICM of University of Warsaw and the ICC of University of Durham. The family of simulations contains parent lower resolution simulations that we dub COLOR (COpernicus complexio Low Resolution), and main high resolution runs dubbed COCO. The COLOR simulations are characterized by an uniform resolution, while the COCO simulations follow a hybrid 'zoom-in' approach, with a high-resolution region of radius 17Mpc/h embedded within a much larger box resolved at low-resolution. The large volume of the high-resolution region contains around 60 MW-size haloes and their satellite populations, resolved at a resolution close to that of the Aquarius level 3 simulations. This is more than sufficient to properly capture the internal structure and properties of subhaloes hosting faint Milky Way satellites, attaining at the same time a good statistical sample of dark matter hosts of various masses located in diverse environments. In addition, the simulations contain a very large number of well-resolved lower mass haloes, whose properties are studied here for the first time with such good statistics. The COCO simulation suite is characterised by WMAP7 cosmological parameters and currently implements two different models of dark matter: cold dark matter (CDM) and warm dark matter (WDM). The WDM model initial power spectrum corresponds to that of a thermal relic mass of 3.3 keV with a sterile neutrino as dark matter particle. Currently the COCOS database provides the data from the following simulations:

  • COCO_CDM - 70.4 Mpc/h main box with a 17.4 Mpc/h high resolution sphere in the centre, 12.8 billion particles, CDM model,
  • COCO_WDM - 70.4 Mpc/h main box with a 17.4 Mpc/h high resolution sphere in the centre, 12.8 - billion particles, 3.3keV WDM model,
  • COLOR_CDM - 70.4 Mpc/h main box with 4.2 billion particles, CDM model,
  • COLOR_WDM - 70.4 Mpc/h main box with 4.2 billion particles, 3.3 keV WDM model,
  • TOY_SIM - 20 Mpc/h box with 262144 particles, CDM model.