Life is full of ironies! As a mailing list we have been discussing the
merits and demerits of neutron powder diffraction resolution. One of the
important contributions to the discussion was Alan Hewat's agreeing to post
an HRPD dataset on the ILL website. Time-of-flight neutron powder
diffraction data hosted on a reactor web-site,
http://www.ill.fr/dif/hrpd-mgo.txt !!!!
Vive l'entente cordialle! To reciprocate Alan's generosity, I would like to
strongly endorse and encourage you all the endorse his plans for a super-D2b
at the ILL.
I have two reasons for doing this.
The first is that D2b is simply already a wonderful machine and a tremendous
resource for those of us (OK principally those in Europe) who use powder
diffraction as a tool for understanding the materials problems that make
life so interesting for us! The new super-D2b
(http://www.ill.fr/dif/2000/2000-D2b.html) will be quite sensational. To
quote Alan on the web-site
"The proposal is to increase both the resolution and the efficiency of D2B
by replacing the detector, with a bank of 128 commercial high pressure He3
detectors and collimators, and the monochromator, with a vertical and
horizontally focusing composite, an extension of the design already proved
on D2B and triple axis machines. This will result in an order of magnitude
gain in efficiency, a significant gain in resolution, and zero loss of
operation of the machine; the new detector bank and monochromator will be
constructed and tested off-line, and installed during a winter or summer
long-shutdown."
Far too good a chance to miss and a snip at the cost!
And the second reason for the strong support comes from Alan's e-mail and I
quote again ...
"Naturally our Science Council need to understand the scientific interest
of such a proposal - to emphasise that point, one (a theoretician) asked at
the last meeting if higher intensity would "just mean more second-rate
science".
Many people (and I strongly believe they are misinformed and I guess all the
subscribers to the mailing list must feel similarly!) such as theoreticians
and scientists from non-condensed matter disciplines do not attach any
importance to the field of powder diffraction. We must realise this and
support one another proactively to ensure that the best laboratory X-ray,
synchrotron X-ray, constant wavelength neutron and time-of-flight neutron
powder diffractometers are available for our use around the world.
As Bob von Dreele said, let's enjoy the apples and the pears - ah, yes and
support the fruit growers as actively as possible!
Bill
