New cold source and reactor shutdown scheduling

[NIST Center for Neutron Research]

STATUS REPORT ON NCNR

We are planning a shutdown of several months duration to install a new cold
neutron moderator, which will provide a substantial increase in neutron
flux (we are predicting 80% more) for all the experiments in the guide
hall.  We are also planning improvements to the optics of the two 30 m SANS
machines, which will provide an additional increase of two or more for
those machines.

Since the shutdown may have an impact on your research schedules, I thought
it would be useful to give you some information on the factors determining
when it will occur.

We estimate that we are still several months away from having all the
components of the new cold moderator fabricated and tested.   This means
that the shutdown could occur in the latter part of 2000, but there is
another factor to consider.  We are also building a new cooling tower, and
will need to connect it up when it is complete.  In order to minimize down
time, I will schedule these two activities to occur at the same time, and
that will require a shutdown time of 3 months, plus or minus one month.  We
have ordered the cooling tower, and are preparing the site for
installation.  The exact time of the shutdown will depend on when we can
complete preparations for both the cooling tower and cold source.  Since
the cooling tower work involves construction, I will not start it in the
middle of winter.  Therefore, either it will happen in late summer/fall if
we are ready, or it will have to be postponed until the beginning of good
weather in 2001 (about April).  I am delaying any announcement because
neither operation is time critical for reactor operation; however, a factor
of two for all cold neutron experiments precludes postponement for a very
long time.  As soon as I can be sure of meeting a schedule, I will make an
announcement.  In the meantime, I will welcome any comments that you care
to make on timing (mike.rowe at nist.gov).

Mike

J. Michael Rowe
Director, NIST Center for Neutron Research
100 Bureau Drive Stop 8560
Gaithersburg, MD 20899-8560
Tel. 301-975-6210 Fax 301-869-4770