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    User name gilman

    Log entry time 11:16:48 on December 11,1998

    Entry number 8183

    This entry is a followup to: 8153

    keyword=VDC multiplicity problem

    Bob Michaels calls and explains a little about the multiplicity problem seen
    in dhist only on the VDC multiplicity. This dhist histogram is uncut,
    whereas the others, and apparently the espace histograms, eliminate
    multiple hits on a single wire by only considering the first hit in time / hit closest
    to that wire. Thus the TDC spectra in dhist and espace spectra look clean.
    Since there is no noise seen on the TDC spectra, apparently the extra hits
    are indeed associated with the real hits, and not just random noise anywhere
    in the chamber, or simply high singles rates.

    There are several possible explanations for getting it seems ~1 extra hit
    on each wire, not all independent, including afterpulsing, too low a threshhold,
    too much gain, larger energy loss (dE/dx) mostly by the pions at the lower
    momenta, bad gas mix...