The ARCHES SED archive - System overview
Archive Search

The ARCHES Archive at CAB (INTA-CSIC) is accessed by means of a web-based fill-in form which permits queries driven by lists of object names and/or coordinates and radius. 3XMM identifiers are directly searched in the ARCHES database. Other object names are resolved using the SESAME service

The output format is in HTML and the Spectral Energy Distributions (SEDs) can be downloaded in VOTable or ASCII format. The magnitude to flux conversion was done using the Filter Profile Service of the Spanish Virtual Observatory

The calculations of the distances between the input data and the targets in the database are done using the Haversine formula. Results of searches using 3XMM identifiers will have associated a distance of zero.

Result from Search

The system provides the following functionalities:

  • Single / Multidownload: SEDs in VOTable format can be retrieved individually or in groups. Multidownload generates a file in ZIP format. Only one instance of each SED found is provided, even if it appears twice in the output table.
  • SAMP: The ARCHES archive implements the SAMP (Simple Application Messaging Protocol). SAMP allows applications to communicate with each other in a seamless and transparent way for the user. This way, the ARCHES SEDs can be easily transferred to other VO application, such as VOSpec or Topcat.
  • Results associated to specific catalogues can be shown or hidden individually.
  • Moving the pointer over a column title will show a tooltip with information about it.
  • Note: fluxes are not computed for upper limits in magnitude
Technical information
  • The ARCHES SED archive currently provides access to the following ARCHES cross-correlated catalogues:
    • 3xmm_galex5ais_ucac4_2mass_allwise_sumssnvss_AKARIfis_bins_sqrt2
    • 3xmm_galex5ais_sdss9_2mass_allwise_sumssnvss_AKARIfis_bins_sqrt2
  • 3XMMe fluxes are given in erg/cm2/s. For the SED building they were transformed to W/m2/m using the following procedure:
    • Divide by 1E+3 to transform fluxes from erg/cm2/s to W/m2
    • Compute the wavelength range (angstroms) from the associated energy (keV) using the formulae

      This way, 6.1 keV - the central point of the 3XMMe XC_EP_8 band (0.12keV-12keV)- is equal to 2.033 angstroms.
    • Divide the flux computed in the first step by the wavelength range in angstroms.
    • Multiply by 1e+10 to express the flux in W/m2/m