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R. J. Goyette

FAQ
1) How do I arrange to do an experiment at IPNS?
1) Here are some instructions for arranging beamtime at IPNS:
  1. Submit a proposal. Go to the Resources page and use the link to get a copy of the Online Proposal Form. Fill out the proposal completely and submit it by following the instructions on the web page where you got the form.
  2. Arrange dates. If your proposal is accepted you will be contacted by the POSY2 Instrument Scientist to arrange beam time.
  3. Register. Once your beamtime has been arranged, register online as an IPNS user, using the appropriate link on the Resources page. Note: For foreign nationals this must be done 30 days in advance.
  4. Confirm. Finally, contact Maria Heinig to confirm the gatepass and make arrangements (lodging/local transportation from airport, etc.) for your visit. Maria's information is located on the Contacts page.
2) What size samples can I bring?
2) POSY2 is designed to accept a two inch diameter sample. Other sample sizes may be accommodated on an individual basis, if advanced discussions with the POSY2 staff deem it possible.
3) Can I study liquid samples?
3) POSY2 does have a liquid sample holder for studying liquid-solid interfaces. The sample holder consists of two circular, four inch diameter silicon slabs which sandwich a Teflon ring, and holding about 23 ml of liquid.
4) How about sample annealing?
4) In-situ annealing up to about 150 degrees centigrade is possible. Ex-situ annealing up to about 200 degrees centigrade is also possible.
5) How long does it take to collect a data set?
5) That depends a lot on the sample. Two inch diameter, strongly scattering samples (i.e., deuterated samples) can collect a complete data set with a Q range out to about .12 in as little as eight hours. Higher Q ranges will take longer. Weakly scattering samples will obviously take longer, and may, for practical reasons, have a lower Q range.
6) What sample thickness can I study? 6) Thicknesses below 30 Angstroms will display few features, and will generally be difficult to distinguish from a bare substrate. Thicknesses above 5000 Angstroms will display features very closely spaced, and may be difficult to resolve.
7) What do I do if I want my samples returned to me? 7) If you are present at IPNS when your samples are run and they have been cleared by health physics, you can carry them back with you. See the link in the Resources section on getting samples cleared by Health Physics. If you are not present, or you leave before one of your samples is completed, we can ship samples back to you, provided we have a complete shipping address, with phone number. Please note that if you want us to ship a sample back to you, you must provide us with as complete an MSDS as possible for your sample materials.
8) Hey, where did the beam go? 8) While the IPNS facility operates seven days a week, twenty four hours a day during normal operations, there are scheduled periods during oerations cycles when IPNS does not produce neutrons for users. These periods are as follows:

1. RCS maintanence checks:

Daily 9:00 A.M. - 9:15 A.M.

2. Accelerator machine research periods:

First Thursday of every run cycle 9:00 A.M. - 11:00 A.M.

Every Tuesday 9:00 A.M. - 3:00 P.M.

3. Moderator annealing:

Every Monday and Friday, 9:00 A.M. - 9:45 A.M.

No data will be collected during these periods. This is normal.
9) When I use the IDL software my backspace key does not work. What happened? 9) This is usually a problem with Windows users running Exceed. The primary keyboard setting does not correctly map the backspace keyboard for use with IDL. Switching to the alternate keyboard usually corrects this problem. Right Click on the Exceed icon in the task bar, scroll down to TOOLS, and select Switch to Alternate Keyboard.
10) What software can I use to fit my data? 10) Our home made IDL software has a simple program to generate a theoretical reflectivity curve from a supplied model for comparison with the experimental data. In addition, reflectivity files can be written in formats compatible with Parratt32 , SURFace2, Reflfit or SimulReflec.