International scoping study of a future
Neutrino Factory and super-beam facility

Physics working group

Council meeting 4:

Phone meeting: 29Nov05, 15h00 GMT

Present:            S. King, M. Lindner, K. Long, Y. Nagashima, L. Roberts, O. Yasuda, H. Murayama

Apologies:         P. Hernandez, D. Harris, M.Mezzetto

Notes

1.         Introduction                                                                                                 Y. Nagashima

2.         Notes from previous meeting and review of actions

3.         Summary of Physics workshop and discussion:

3.1 Theory: SK

Productive session on Friday, talks presented were relevant for what theory group needs to achieve. AdeG’s roadmap talk should be reviewed carefully as most issues were addressed in that. L.Everett from US wants to be involved as does S.Hannestad from Denmark. Neither could come but should be invited to either or both of the next meetings.

‘Theory parallel’ on Thursday PM to discuss writing of the document. Recognised the need to make coherent document and that this would take a significant amount of work. LR emphasised the need for an editor for the whole chapter. Agreed that Council should be editorial board for physics chapter.

3.2 Phenomenology: OY

Four talks on flavour-changing interactions that could mimic neutrino oscillations. Talks gave a good understanding of what has been done so far. Now there is a need to do some systematic work to identify how measurements at the neutrino facilities can address the models.

Sterile neutrinos, especially 3+2 schemes, offered interesting possible descriptions of the data. Recent work, however, seems to indicate that such schemes can not explain the atmospheric neutrino data. Those working on such models are now trying to make alternative fits looking for a best-fit point that takes into account the atmospheric constraint. If such a fit can be found, then there is a scenario which can be investigated within the phenomenological working group. Sorel, the author of this work, will be invited to the KEK workshop.

Y.Grossman and J.Valle have been invited to contribute to the report.

HM asked whether there is an effort to build models that can give effects at a level that is interesting from the point of view of future experiments. OY replied that only example which he is aware of is that being developed by Y.Grossman, this is work in progress.

3.3 Experimental: KL

Productive to have detailed conversations between those using GLoBES, the Madrid, and the Valencia codes. Though disagreements were observed in the studies performed in preparation for the workshop, these were shown to be due to different flux, or detector-performance assumptions. This clearly indicates the need to work with the Accelerator and Detector groups to define the reference set of assumptions. During the workshop it was shown that the three codes gave good agreement when all assumptions were the same.

Joint session with the Detector group on Thursday was very valuable. The various detector options were discussed and the need to make realistic assumptions for the various systematic errors depending on the case being considered was emphasised. It was agreed to communicate using grids of efficiencies, resolutions, etc. stored in ntuple files. Later it may be necessary to exchange event-data files. It was agreed that the first input from the detector group would be provided at the KEK meeting.

ML emphasised the need to define the flux assumption particularly for the beta beam. It was therefore decided to invite M.Lindroos or one of his co-workers to the KEK meeting.

Action 3.3.1: KL: Invite M.Lindroos to the KEK meeting.

3.4 Muon physics: LR

Two interesting theory talks at the w/s. Informal discussions have taken place over what should be in the document, responsibilities for different areas have been allocated though writing assignments have not yet been agreed. Goal is to be very well along in the planning at the Boston meeting. LR needs to deputise, perhaps to Y.Kuno, the organisation of the KEK meeting.

4.         What should be done before KEK plenary meeting

YN presented block schedule that had been circulated before the meeting. Suggestions for Physics working group plenary speakers were made. Summary of work in preparation for the KEK meeting and plans for the KEK meeting itself, KL. Final Physics group summary – P.Hernandez or W.Winter.

Action 4.1: KL: Email M.Goodman to ask him to advertise KEK meeting.

5.         What should be done at KEK meeting

To be defined by conveners.

6.         Time line for preparing (final) reports

YN commented that SK and LR have a good idea of how to proceed. OY and KL need to define content of report over the period up to the Boston meeting. It was agreed to make a first attempt at the table of contents at the KEK meeting.

Action 6.1: KL: Ask S.Choubey to draft section on present and near future experiments.

7.         Any other items

Next phone call in two to three weeks, by this call, conveners should have a good idea of the agenda for the KEK meeting’s parallel sessions.

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