<html>
  <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    Dear all,<br>
    last week I and Dan had a short chat about a strategy on  how the
    PAC-suggested bg measurements would match a BDX-DRIFT NSF proposal
    (to be submitted by the end of October).<br>
    We agreed that we should work in the spirit of the  full bg
    characterization: the low energy part with BDX-DRIFT  and the high
    enregy part with BDX-prototype deploying the two detectors.<br>
    <br>
    It's clear that JLab management (as the PAC) has no clear directions
    for these tests at JLab (see Elton's discussion with Rolf) and, if
    we want to be efficient, we probably better want to propose
    something and discuss it with Bob and the PAC (rather than having a
    discussion starting from scratch). The drawback of this strategy is
    that we may do some useless work, if we we are not interpreting
    correctly what they want.<br>
    <br>
    We would need to measure the beam-related bg in an experimental
    configuration (beam, dump, shielding) as close as possible as the
    one proposed in the Proposal but all these conditions together will
    not be satisfied at the same time, in the same place. I drafted a
    table with the different options specifying the experimental
    conditions and which concerns it may address (requires more input
    from all of you).<br>
    Be aware that each of the possible option is almost an experiment
    per-se and, before the next PAC, more than one test is difficult to
    conceive (we need to find a compromise!).<br>
    <br>
    The options I see are the following:<br>
    <br>
    <table border="1" cellpadding="2" cellspacing="2" width="100%">
      <tbody>
        <tr>
          <td valign="top"><b>Where?</b><b><br>
            </b></td>
          <td valign="top"><b>Opportunity (politically)</b><b><br>
            </b></td>
          <td valign="top"><b>Beam </b><b>(GeV)</b><b><br>
            </b></td>
          <td valign="top"><b>Dump</b><b><br>
            </b></td>
          <td valign="top"><b>Current</b><b><br>
            </b></td>
          <td valign="top"><b>Timescale</b><b><br>
            </b></td>
          <td valign="top"><b>shielding</b><b><br>
            </b></td>
          <td valign="top"><b>shield staging</b><b><br>
            </b></td>
          <td valign="top"><b>logistic</b><b><br>
            </b></td>
          <td valign="top"><b>Low E n</b><b><br>
            </b></td>
          <td valign="top"><b>High E n</b><b><br>
            </b></td>
          <td valign="top"><b>muons from the dump</b><b><br>
            </b></td>
          <td valign="top"><b>neutrino</b><b><br>
            </b></td>
          <td valign="top"><b>similar to the real set up</b><b><br>
            </b></td>
        </tr>
        <tr>
          <td valign="top">JLab Hall-A<br>
          </td>
          <td valign="top">5/5: High<br>
          </td>
          <td valign="top">10<br>
          </td>
          <td valign="top">hall-A<br>
          </td>
          <td valign="top">high<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">dirt only<br>
          </td>
          <td valign="top">no<br>
          </td>
          <td valign="top">2/5: dig a small hole in front of the dump<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">probably not<br>
          </td>
          <td valign="top">3/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top">JLab Hall-A<br>
          </td>
          <td valign="top">5/5: High<br>
          </td>
          <td valign="top">10<br>
          </td>
          <td valign="top">ad-hoc<br>
          </td>
          <td valign="top">low<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">concrete<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">3/5: much simple<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">not<br>
          </td>
          <td valign="top">not<br>
          </td>
          <td valign="top">2/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top">JLab Hall-B<br>
          </td>
          <td valign="top">4/5: medium<br>
          </td>
          <td valign="top">10 <br>
          </td>
          <td valign="top">hall-B<br>
          </td>
          <td valign="top">medium<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">magnet? concrete?<br>
          </td>
          <td valign="top">yes (?)<br>
          </td>
          <td valign="top">3/5: the tunnel is accessible<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">probably not<br>
          </td>
          <td valign="top">3/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top">Jlab<br>
            Hall-D<br>
          </td>
          <td valign="top">4/5: medium<br>
          </td>
          <td valign="top">10 <br>
          </td>
          <td valign="top">Hall-D<br>
          </td>
          <td valign="top">medium/high<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">iron/concrete<br>
          </td>
          <td valign="top">no<br>
          </td>
          <td valign="top">4/5: avove ground, requires all services<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">probably yes<br>
          </td>
          <td valign="top">4/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top">LNF BTF<br>
          </td>
          <td valign="top">3/5: low/irrilevant<br>
          </td>
          <td valign="top">0.75<br>
          </td>
          <td valign="top">ad-hoc<br>
          </td>
          <td valign="top">medium<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">possible<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">5/5: simple, dedicated facility<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">no<br>
          </td>
          <td valign="top">no<br>
          </td>
          <td valign="top">no<br>
          </td>
          <td valign="top">3/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top">SLAC<br>
          </td>
          <td valign="top">2/5: competitors?<br>
          </td>
          <td valign="top">10<br>
          </td>
          <td valign="top">ad-hoc<br>
          </td>
          <td valign="top">medium<br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top">possible<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">5/5: simple, dedicated facility<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes<br>
          </td>
          <td valign="top">yes (?)<br>
          </td>
          <td valign="top">4/5<br>
          </td>
        </tr>
        <tr>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
        </tr>
        <tr>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
        </tr>
        <tr>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
          <td valign="top"><br>
          </td>
        </tr>
      </tbody>
    </table>
    <br>
    Votes and comments simply reflect my personal, preliminary (before
    the discussion) opinions.<br>
    Please do the same exercise, filling the table, and complete it
    including other relevant information if you think I missed something
    to discuss it at tomorrow's meeting.<br>
    We shall define the best configuration (that better matches the PAC
    recommendations running a test next spring)  and have a plan to
    propose at a meeting  with Bob, Jim Napolitano and the two reviewers
    by mid October to get feedback (from PAC members) and approval (by
    Bob, since many of them involve Jlab).<br>
    Cheers<br>
    Marco<br>
  </body>
</html>