Re: Baseline Optimization Memo

From: Josh R Klein <>
Date: Fri May 14 2004 - 13:26:57 CDT

Hi, Jon,
   The memo looks very nice. One comment I have is that
we probably should not treat systematics and statistics on an
equal footing---for the same total uncertainty, I'd rather be
statistically limited, since we know how those uncertainties are
distributed, and we usually don't know for systematics. In other
words, build the biggest experiment you think you can afford, and
place it at a baseline which minimizes the absolute systematic
uncertainty, not the ratio to statistical uncertainty.

    In any case, I suppose I would argue for the slightly closer baseline if
that allows a better rate+shape analysis. I think that although the sources
of uncertainty are larger for such an analysis (relative energy
non-linearities and background shapes matter much more), the additional
information should provide an overall reduction in the total systematic
uncertainty (not to mention, be a more believable measurement in general).

    Also, Bayes would say that dM2 is likely to go up from where it is,
not down, since that is where it came from...though I suppose I wouldn't be
willing to bet too much money on it either way.


On Fri, May 14, 2004 at 12:22:08PM -0500, Jonathan Link wrote:
> Hi All,
> Now that we have the go ahead from Exelon, we are hoping to move rather
> quickly on getting the bore holes dug at Braidwood. The optimal
> location of the near shaft is well understood, but I believe that we
> should revisit the question of what is the optimal location for the far
> shaft before the bore holes are dug. Our objective is to choose the
> best location given our current knowledge of delta m^2 and the
> measurement philosophy, and the odds of what we select now being right
> are not great, but we should try anyway. Since a bore hole at the exact
> location of the shafts will be critical to reducing the project
> contingency, the cost of getting it wrong now will be $50K to $80K to
> drill prior to bidding the civil construction.
> I have written a memo describing a recent baseline study I conducted,
> and discussing the risks associated with uncertainties like delta m^2.
> We would like to initiate the bidding process by May 24th, so the
> internal discussion should be complete by then. Please take sometime to
> look at the memo and enter the debate.
> Thanks,
> Jon Link
Received on Fri May 14 13:27:03 2004

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