2nd Workshop on supporting Polarised SANS data

2nd Workshop on Supporting Polarised SANS Data

Thanks to the hard work of Steve King (ISIS), Dirk Honecker (ISIS), Lucas Wilkins (ISIS), and Annika Stellhorn (ESS) there is a proposed extension to the NXcanSAS v1.0 to support the various forms of polarized/magnetic SANS measurements that are performed.

They have written up the proposal on the canSAS wiki here : NXcanSAS_v1.1

They have worked to ensure compliance with the core definition of NXcanSAS with only additions to the standard needed and no other modifications.

To fully implement their vision, some underlying changes to NeXus would be needed, which they have discussed with Freddie Akeroyd as to the reasonableness of their proposal. Pete Jemian has offered to take these proposals to the NIAC.

In order for us to finalise the data format, we will hold a workshop/hackathon at ESS and are proposing April 2nd this year.

The goals of the workshop are to :

1. Finalise the format (including deciding on which of the recommended proposals on the wiki we accept)
2. Produce real-code example of implementation
3. Outline the work needed to read the format into relevant codes (primarily SasView)
4. Initiate the write up of proposal to NIAC for adoption as an update to the NXcansas definition.

Agenda

In order to try to accommodate our US colleagues, we will arrange the day as follows (all times CEST, BST is -1 hour, EDT is -6 hours from CEST).

• 09:00 ESS tour (Annika, Dirk, Andrew)
• 11:00 On-site discussions and preparation (Annika, Dirk, Andrew)
• 12:00 Lunch
• 13:00 Overview of proposal
• 13:30 Summary of opinions/comments
• 14:00 Discussion of recommended items
• 14:30 Discussion and work on goals 2-4 (breakout as needed)
• 17:30 Close-out, next actions and work assignments.

Participants

• Annika Stellhorn (ESS)
• Dirk Honecker (ISIS)
• Lisa Debeer-Schmitt (ORNL)
• Jonathan Gaudet (NIST)
• Jeff Krzywon (NIST)
• Lucas Wilkins (ISIS)
• Mial Lewis (ISIS)
• Adrian Diaz Alvarez (ISIS)
• Oliver Hammond (ESS)
• Andrew Jackson (ESS)

Meeting Notes

Overview of Proposal

Presentation from Annika & Dirk :

Discussion and Work on Goals 2-4

Implementation Example

ISIS Mantid team have prepared an example of a possible implementation (remove.txt extension to use)

Current mantid output : File:half pol data2d group.nxs.txt

Proposed NXcanSAS output : File:half pol data2D larmor nxcansas.h5.txt

Work needed to implement reading

Jeff Krzywon / SasView

NIAC proposal

Figure out process ... what do we need to do (probably PR on relevant github repo?)