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    Re: Dip uncertainty
    From: Alexandre Eremenko
    Date: 2004 Dec 6, 20:42 -0500

    I did some calculations and obtained a result
    which shows that the matter is more complicated
    than it was suggested in our "thought experiments".
    In the Bruce experiment,
    all refraction was concentrated on one single height
    the height of the small observer.
    In this idealized case, the error (ERR) of the dip due
    to refraction of the tall observer is
    approximately
    ERR=err.sqrt(h/H),
    where err is the similar error of the short observer.
    So ERR is indeed somewhat smaller.
    (So Trevor was right in analysing Bruce's imaginary
    experiment!)
    On the other hand, when we increase H,
    the part of the refraction between the two guys increases,
    and it is hard to imagine that most of the refraction
    happens on a very small height.
    (Recall my thought experiment when H is higher than the whole
    atmosphere).
    
    Now, taking into account that we are only talking of the
    "anomalous part" of the dip correction due to the refraction,
    it seems that the question is impossible to settle theoretically.
    One needs experiments.
    
    Alex.
    
    
    

       
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