Working groups

HB2012 have formed five working groups (WG). The WG conveners are responsible for organizing the parallel sessions including joint sessions.

WG-A: Beam dynamics in high-intensity circular machines
Conveners: G. Franchetti (GSI) , E. Metral (CERN), J. Holmes (SNS)

WG-B: Beam dynamics in high-intensity linacs
Conveners: P.A.P. Nghiem (CEA-Saclay), Zhihui Li (IHEP), D. Raparia (BNL)

WG-C: Accelerator system design, injection, extraction, beam-material interaction
Conveners: N. Mokhov (FNAL), H.W. Zhao (IMP), D. Li (LBNL)

WG-D: Commissioning, operations and performance
Conveners: Y. Sato (J-PARC), R. Schmidt (CERN), M. Plum (SNS)

WG-E: Beam diagnostics and instrumentation for high-intensity beams.
Conveners: R. Doelling (PSI), N. Hayashi (J-PARC), V. Scarpine (FNAL)

Dear Colleagues.

HB2012 will be held on September 17-21. The program has been posted onhttp://hb2012.ihep.ac.cn/. Besides the talks, the following discussion sessions have been scheduled:

Tuesday afternoon:
Working group D (Commissioning, operations and performance)
Working group E (Beam diagnostics and instrumentation for high-intensity beams)

Wednesday afternoon:
Working group C (Accelerator system design, injection, extraction, beam-material interaction)

Thursday afternoon:
Working group A (Beam dynamics in high-intensity circular machines)
Working group B (Beam dynamics in high-intensity linacs)

The conveners of WG-D and WG-E call the participants (all the HB2012 participants planning to attend the discussion sessions, not only those giving talks or providing posters)to prepare for the discussion sessions on Tuesday.

 

  1. The WG-E convenersĄ¯ call:?

As the title "52nd ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams" suggests, the workshop is centered on beam dynamics. Hence, it is particularly appropriate to focus the working group E discussion on aspects of beam diagnostics that are at the boundary to beam dynamics.

As we all know, one of the central issues in developing and maintaining high power accelerators is to limit the beam loss and activation of the machine (e.g. losses < 1W/m). To initiate discussion, one may raise the question "Is it possible to know the beam (and the machine) in such detail, that we are able, with the aid of simulation, to fully understand the beam losses and are subsequently able to reduce them in a predictable way?". (Ingo Hofmann will present a talk also addressing this theme on the Monday afternoon plenary session.)

At first instance, it appears to be a task for beam dynamics to study this case through simulation and to subsequently formulate requirements to beam diagnostics. However, beam diagnostics can also support this effort by providing the constraints (dynamic range, accuracy, spatial and temporal resolution) with which the beam parameters and beam losses can be measured (either with standard or more advanced tools).

But we can also take a look at the present "environment" in which answers to the above question have to evolve, and ask ourselves how far we have already come.

In this respect, we invite the speakers and poster contributors from working group E, and all other interested parties, to present a short presentation (1 to 3 minutes with 0 to 3 slides), adressing some of the following topics (A-C), in the light of their own accelerator:

0) What machine? Already in operation?

Topic A
1) What diagnostics are used for losses?
2) What diagnostics are used for transverse/longitudinal beam distribution (core and halo)?
3) What diagnostics are used for other projections of the 6D-phase space?

Together with an estimation of the numbers for dynamic range, accuracy, spatial and temporal resolution

We are of course not expected in an 80 minute discussion period, to reach a comprehensive and detailed statement from what is already a vast field (see e.g. http://cas.web.cern.ch/cas/France-2008/Lectures/Wittenburg-halo2.pdf). We should, however, aim to come to a consensus (within? ~20 minutes) on what we believe to be both standard and feasible in the future.

Topic B
4) Is there a need to improve beam losses?
5) To what degree the beam losses are understood? (Do you feel it is at all possible to get a sufficiently detailed understanding that will allow the prediction of beam losses?)
6) Are the diagnostics of 2), 3) used to improve the understanding of beam losses which occur during standard operation? (or mainly for empirical tuning or trouble shooting?)
7) Is there a clear plan regarding how to proceed with improving beam losses and to what extent are diagnostics involved?
8) Are our beam dynamics colleagues aware of the performance capabilities/constraints of the beam diagnostics? Is further improvement called for and are they able to provide well-founded specifications?

Topic C
9) Other points which complement the above.

Each contribution (we hope for approximately 15) should be followed by a short discussion. We may start with Topics A and continue with B, C. A general discussion will then follow if time permits.

2. The WG-D conveners have built a discussion program focused on answering the following issues:

- Observation of beam losses (e.g. time structure, other parameters ...)
- Reducing beam losses with operational parameters away from the design set points
- Reducing beam losses (or concentrating beam losses at a few locations) using collimators
- Minimizing beam losses due to beam transfer from one accelerator to the following accelerator
- What parameters are important?

The second issue - reducing beam losses with operational parameters away from the design set points - is especially valuable as it is rarely discussed.

During the Working Group D discussion session on Tuesday afternoon, we would be happy to hear from anyone in attendance about experiences that relate to the above issues at their home facilities.

Our intent is to compile the data presented in the WG-D talks and discussion session into a document that summarizes and compares these data for the various accelerator facilities.