Meetings | SAS Data Analysis Questionnaire 1997

In May 1997, we sent out a questionnaire concerning the use of facilities and data treatment programs by the small-angle scattering community of the ILL and the ESRF, as well as their experience with different data formats.

We summarise here the results of this exercise.

Altogether, we received answers from 55 out of about 500 people to whom we had sent the e-mail. Their answers are summarised below:

1. Fields of study

1. Biological assemblies: 18

2. Membranes structures: 11

3. Colloids: 17

4. Conc. polymer systems: 14

5. Copolymers: 18

6. Polymer networks: 8

7. Rheological studies: 11

8. Voids & defects: 5

9. Phase studies, nucleation etc: 19

10. Critical phenomena: 11

11. Magnetic flux lattices: 3

12. Time resolved experiments: 22

13. Other, please specify: 8

Fields named under "other" were: Liquid crystals (3), polymer adsorption, scattering from gratings, supported metal catalysis, protein folding, crystallization

2. Synchrotrons and/or neutron sources used:

(The European bias is primarily a reflection of our e-mail list which started from ILL and ESRF user lists)

20 were named (multiple nominations)

ILL 28

SRS (Daresbury) 18

ESRF 17

ISIS (RAL) 15

DORIS/HASYLAB/DESY/EMBL 11

LLB (Saclay) 6

RISO 6

LURE (Saclay) 5

NIST 4

ORNL 4

Photon Factory (Japan) 3

NSLS (Brookhaven NL) 3

GKSS 3

KFA JULICH 3

KENS (Japan) 2

Argonne 2

Elettra (Trieste) 2

HMI 2

Studsvik 1

Los Alamos 1

3. Kinds of data treatment

1.) Indirect transforms 19

2.) Particle size distribution 20

3.) Fitting of 1D, 2D functions 32

4.) Model fitting 34

5.) De-smearing 13

6.) Other, please specify 17

Data treatment mentioned under "other" were:deconvolution p(r) -> rho(r), single-crystal analysis, Hayter-Penfold analysis, MaxEnt, Fourier transforms, Crowley inversion, time evolution of Bragg peaks, measurement of orientations, analysis of projections, correlation functions, shape analysis.

4. Exported data reduction, data analysis or interconversion utilities

Site supplied: SRS, OTOKO, BSL, ILL, Genie, Colette, Oak Ridge

Distributed/commercial: MAR, Peakfit, Transform, PDH/ITP, SCT, Mathematica, Cerius, RFIT, Gnom, Image Quant, PVWave, Igor, Spyglass, Origin, Lotus

Own: 36 users reported on the use of their own programs, of which most are neither available to the community nor documented

5. Major treatment problems related to data formats

14 had no problems dealing with their data

6 mentioned that they would like a common standard

2 commented on Unix <=> VMS problems

6. Formats

7 marked a distinct preference for simple ASCII data

2 proposed CIF, especially for sequences of 2-D data

1 proposed that an EXCEL option would be generally useful

6 wished to have interconversion programs available, especially in source form

Amongst those commenting there was a general wish for documentation on formats in use, at least as a starting point even if a common standard could not be envisaged.

 

SAS groups of ESRF and ILL, Grenoble

sas@ill.fr

Monitored by Wim Bras(ESRF), Claudio Ferrero(ESRF), Ron Ghosh(ILL), Roland May(ILL) Peter Timmins(ILL).