From: Dawsonzhu@aol.com
Date: Fri Oct 03 2003 - 13:21:18 EDT
Dave Siemens wrote:
> I did a quick search by Google on "Carbon 14." First, the ratio of
> radio-carbon in contemporary living things is about 10^-12. This is the
> 100% level, approximately, for there are technicalities to the standard.
> Measurement by the most advanced techniques gets down to a little more
> than 1%, for an age of 40,000 years. Theoretically, the newest techniques
> might get to 60K, but the practitioners say it doesn't work. In other
> words, 0.1% is a full order of magnitude better than the best labs get.
> Do you suppose it's artifactual?
>
Having personal experience trying to do careful measurements of muons
at several different accelerator facilities, I would think it is just a
matter
of noise. In theory, if you obtain sufficient statistics, your error bars
drop by 1/sqrt(N) where N is the number of events. However, it seems
practically speaking, you have all sorts of things ricocheting around or
decaying in a beam line. Eventually, your error bars flatten out, and
you cannot take some data very seriously even if you have very small
error bars. There is also the practical matter that you also typically have
to apply for beam time and you have limited time for set up, preparation
and fine tuning in a given experiment. Then there is just plain bad luck.
All these factors conspire against you or reap havoc on your detectors
when you push your measurements to the limit.
I'm sure a gain of 100 is perhaps possible, but more than that may be
quite challenging under the circumstances. My experience is not
exactly in the same area , but that would be my take on it.
By Grace alone we measure,
Wayne
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