Workshop on Nuetron Scattering Instrument Design

[Hjelm, Rex]

Workshop on
"Methods for Neutron Scattering Instrument Design"

Meeting Goals

In view of the current level of activity worldwide  associated with the design and 
construction of new, next-generation neutron sources, it appears highly desirable 
to review the design tools and techniques available to the neutron scattering 
community fo

1. Review the present situation regarding approaches to neutron scattering 
instrument design and the tools available for this purpose.

2. Determine the present and future needs of the neutron scattering community 
regarding techniques and design tools for neutron scattering instrument design.

3. Given that these tools can be used in a variety of ways for:

- Analysis of existing instruments,
- Design of new instruments,
- Optimization of existing or new instruments,
- Planning of experiments,
- Teaching,

how do we best address the needs of the community in these various categories? 
Where do we focus future efforts? How do we share information and codes between 
different institutions?

4. How can we validate our design tools? How do we implement proposal mechanisms 
that would allow beam time to be devoted to instrument development and code 
benchmarking? Should we create dedicated beamlines to test neutron optical 
elements, measure their

5. How do we measure instrument performance? Should we define "standard" test to 
measure instrument performance? What are meaningful figures of merit?

Some of these questions will be addressed directly by invited speakers.  Others are 
appropriate topics for discussions between the meeting participants.

Meeting Dates and Location

We have scheduled the workshop for September 23-25, 1996 at Lawrence Berkeley 
National Laboratory, Berkeley, California.  If you wish to receive further 
information, please fill out the form at the end of this document and return it to:

                        Molly O. Field
MS 65
Lawrence Berkeley National Laboratory
1 Cyclotron Road
Berkeley, California 94720

or contact one of the organizers.   Information and registration forms are 
available at our WEBsite at http://www.lansce.lanl.gov/instrument_design.html

Meeting Organization

Organizing Committee:

                I. Anderson (Institut Laue-Langevin)
                J. Copley (National Institute of Standards and Technology)
                K. Crawford (Argonne National Laboratory)
                L.L. Daemen (Los Alamos National Laboratory)
                W. Hamilton (Oak Ridge National Laboratory)
                R.P. Hjelm (Los Alamos National Laboratory)
                M. Johnson (Rutherford-Appleton Laboratory)
                G. Kearley (Institut Laue-Langevin)
                
Meeting format

* Sessions will consist of (invited) oral presentations focused on broad overviews. 
We will try to limit formal presentations to 3 or 4 hours per day to leave ample 
room for discussions. During these discussions, participants are invited to make 
brief (5-
* Computers (PC, Mac, Workstation) and printers will be made available to 
participants for code demos.  Direct access to the Internet will be provided to 
simplify the transfer of codes to the local computers and/or allow demos to be run 
remotely.
* The proceedings of the Workshop will be published either as an EO-LBNL report or 
in an archival journal.

Participants

M. Bourke (LANL)
J. Browne (LANL)
T. Brun (LANL)
J. Carpenter, (ANL)
J Copley (NIST)
K. Crawford (ANL)
B. Czirr (MSI)
B. David (ISIS)
L. Daemen (LANL)
M. Fitzsimmons (LANL)
P. Ferguson (LANL)
A. Freund (ESRF/ILL)
R. Gaehler (TUM)
W. Hamilton (ORNL)
C. Hayes (ILL)
G. Ice (ORNL)
M. Johnson (RAL)
M. Khan (CXrL)
M. Lampton (Stellar Software)
D. Martin (ISIS)
F. Mezei (HMI),
G. Olah (LANL)
W. Oosterhuis (BES/MS)
L. Passell (BNL)
M. Popovici  (U. Missouri)
T. Reiker (SANDIA/UNM)
R. Pynn (LANL)
J. Roberts (LANL)
L. Robertson (ORNL)
R. Robinson (LANL).
N. Rosov (NIST)
P. Seeger (LANL)
D. Sivia (RAL)
G. Smith (LANL)
S. Spooner (ORNL)
P. Thiyagarajan, (ANL)
H. Tiezte (ISIS/KFA)
F. Trouw (ANL)
W. Wagner (PSI),
U. Wildgruber (BNL)
G. Williams (ISIS)
I. Zalzinyak (JHU/NIST)
C. Zeyen (ILL)


Tentative Meeting Agenda

Wecome and meeting goals

9:00-9:30 - TBA


Session 1: Design Tools for X-ray Scattering Instruments

Topics - Overview of design tools currently available
- How are these tools being used and by whom ?
- What was the general approach/philosophy followed in the development of these   
tools ? What was the history of the developments of these design tools ?
- How is the development of these tools supported ?
- What are future directions for the development of these tools ?

Chairman::  J.R.D. Copley

9:30 - 10:10:  G.E. Ice (ORNL) - Modeling of x-ray beamlines and devices.

        10:10 - 10:30:  Break

10:30 - 11:10:  A. Freund (ILL/ESRF) - Common aspects and basic differences of 
optical devices for x-ray and neutron optics & design optimization of synchrotron 
radiation beamlines.

11:10-11:50  M. Khan (U. Wisconsin) - SHADOW

11:50 - 12:30  Open discussion: Lessons learned from the x-ray scattering 
community.


12:30 - 14:00:  Lunch


Session 2: Design Tools for Neutron Scattering Instruments

Topics  - Overview of existing tools
- Approaches to neutron scattering instrument design
- Examples of successful designs
- Examples of mistakes and lessons learned

Chairman::  R.P. Hjelm

14:00-14:40:  L. Passell (BNL) - Historical Overview of Neutron Instrument Design.

14:40 - 15:20:  K. Crawford (ANL) - Approaches to instrument design at pulsed 
spallation sources.

15:20 - 15:40: Break

15:40 - 16:20:  J. Carpenter (ANL) -  Matching instruments and sources.

16:20 - 17:00:  Discussion: Lessons learned on neutron instrument design.


Session 3: Instrument Design - Analytical & Numerical Techniques

Topics - Examples of successful instrument design
- Phase space transformation methods
- Ray tracing
- Optimization methods
        - Examples of successful instrument design.
- Figures of merit for measuring performance and optimizing instruments.
- Benchmarking: comparison of calculated and measured performance.
- Monte Carlo and other numerical techniques.
- Treatment of background and noise.

Chairman::  W. Hamilton

9:00 - 9:30:  M. Johnson (RAL) - Figures of merit.

9:30 - 10:00: D. Sivia (RAL) - Figures of merit: another view.

10:00 - 10:30:  B. David (RAL) -  Figures of merit: the view from the experimental 
perspective.

10:30 - 11:00: Break

11:00 - 11:40: R. Robinson (LANL) - Matrix methods.

11:40 - 12:30:  Discussion.


12:30 - 14:00:  Lunch.


Session 4: Instrument Design - Analytical & Numerical Techniques

Chairman::  K. Crawford

14:00-14:35: R. Gaehler (TU Muenchen) - Coherence properties of neutron beams for 
scattering instrumentation

14:40 - 15:15: P. Seeger (LANL) - MCLIB, a general Monte Carlo library for 
simulation of neutron scattering instruments.

15:15 - 15: 35:  Break

15:35 - 16:00: U. Wildgruber (BNL) - NEUTRAK,  The Brookhaven Monte Carlo package.

16:00 - 17:00 Discussion:  The codes:  What can be done to improve code sharing and 
collaboration?  Other computational aspects.


Session 5: Modeling of Neutron Optical Components

Topics - Overview of existing models.
- Generation of scattering kernels for simulating samples.
- Identify model deficiencies and need for new/improved models.
- Validation of models.

Chairman:  L. Daemen

9:00 - 9:40: J.R.D. Copley (NIST) - The design of a reactor-based time-of-flight 
spectrometer

9:40 - 10:00:  C. Hayes (ILL) - Toroidal mirrors.

10:00 - 10:30: Break

10:30 - 10:50: N. Rosov (NIST) - Modeling components of an neutron spin echo 
spectrometer.

10:50 - 11:20: C. Zeyen (ILL) - Modeling magnetic optics of an neutron spin echo 
spectrometer.

11:20 - 11:40:  M. Popovici (U. Missouri) - Modeling triple-axis spectrometers 
optics.

11:40 - 12:30:  Discussion


12:30 - 14:00: Lunch


Discussion: Present and Future Needs of the Community

Goals:  - Open discussion

Chairman:  M. Johnson

14:00 - 14:40   Presentations on the present and future needs for instrumentation 
design:

J. Carpenter
R. Pynn
W. Wagner
F. Mezei

14:40 - 16:00  DiscussionÐPresent and future needs of neutron scattering instrument 
design.