Visual and IR photometric systems

From: Chris Lidman (clidman@eso.org)
Date: Sat Feb 07 2004 - 22:22:50 PST

  • Next message: Tony Spadafora: "i-band meeting postponed until tomorrow"

    Hi Serena,
      I did a quick test on the compatibility of the fundamental ZPs of
    visual and near-IR standard star systems by examining the median V-J
    colour of A0V stars that are in the Hipparcos catalogue. I did
    this by cross correlating Hipparcos stars with the 2MASS catalogue. I
    first pruned the Hipparcos catalogue of obviously reddened stars by
    choosing stars with B-V < 0.05.

      The resulting median colours of stars in the matched catalogue (557
    stars) are

    B-V = 0.015
    V-J = 0.070
    J-K = 0.002

      I find this interesting. I must say, that I am not too surprised
    by the discrepancy. I might refine these numbers over the next few days
    as I restrict the matching by other criteria.

    Cheers, Chris.
        

    This archive was generated by hypermail 2.1.4 : Sat Feb 07 2004 - 22:32:11 PST