1. Current impedance issues

2. Impedance issues
Short term issues: Isolated requests for impedance calculations of elements before hardware modification or installation
Medium term issues Implementation and population of the impedance database (ZBASE) for PSB, PS, SPS and LHC.
Long term issues Improving our methods to compute, simulate and measure impedances General questions

3. Long term : Understanding and improving our methods
General questions:
Impedance of structures with particles at low energy (PSB, PS)
Formula for impedance of elliptic chamber
Formula for impedance of elements with finite length
Impact of external circuits of kickers
Non linearity of the wake with transverse offset
Properties of materials at very high frequencies? Measurement methods?
Reliability of wire measurements
Anomalous skin effect for CLIC (and maybe LHC at low temperature)
Vanishing longitudinal impedance at low frequency (“hidden bypass”)
Other ways to measure, compute, simulate impedance on bench or with beam?

4. Medium term : implementation of ZBASE
Implementation of the Java based ZBASE
Improvement of the Matlab based ZBASE (at the moment more than 5000 lines…)
Allow possibility to import efficiently from different impedance calculation codes ABCI/ReWall/CST, for different machines and for varying beam parameters.
Use the new model of kickers for the SPS impedance model

5. Short term : Impedance of single elements (1/2)
LHC:
plan of new vacuum chamber in ATLAS, request from Mark Gallilee/Ray Veness on December 2010(reduction of pipe aperture, new unshielded bellow, transition)
 M4 Holes in DS collimator design request by Marc Timmins on February 2011 
MKI request by (Mike Barnes) and MKD
collimators with BPMs
PIMS+ unshielded bellows
RF cavities
Rotatable Collimators
beam screen weld
beam screen holes
TDI
Septa
Trapped modes in collimators

6. Short term : Impedance of single elements (2/2)
SPS:
Improve impedance model (request from SPS Upgrade study team)
Pumping ports
MSE, MST and ZS
Shielded MKE kickers (request from Mike Barnes)
Segmented MKPs
Multilayer kicker (MKDH) PS
Extraction kicker (request by Sandra Aumon on February 2011)
Build the impedance model
PSB
Kickers with external circuit
Y piece and ceramic chamber (request from M. Barnes and W. Wetterings)

7. Purpose of these informal meetings
Discuss new results, problems and questions
Gather and keep an eye on impedance requests
Set priorities and needs for the team to be discussed with direct supervisors
In brief…. Nothing changes…