Pending RLC Actions

transverse impedance items where urgent answers were/are needed

action date in charge priority status
get MAFIA input files & understand boundary conditions used for Y Chamber 28.11.2006 EM high DONE, LCU 26.02.2007
follow up of GSI resistive-wall impedance result 07.07.2006 EM high IN PROGRESS, 19.09.2006, 26.09.2006, 24.10.2006
follow-up impedance of LHC septa 07.04.2006 EM high TO BE FOLLOWED UP
contact D. Macina to organize meeting with experiments on TCTV aperture 17.03.2006 FR highest addressed by RLC discussion on 07.04.2006, CLOSED LCU 26.02.2007 (RA)
contact M. Mayer to question chamber dimensions 17.03.2006 EM, AG highest CLOSED LCU 26.02.2007 (RA)
check whether a reduction of transverse dimensions
of TCTV vacuum chamber is compatible with Totem Roman Pots requirements.
10.03.2006 FR high CLOSED LCU 26.02.2007 (RA)
compute collimation performance and loss maps
with 2 m beta-star at IP2 and IP8 and larger TCTV gaps
17.02.2006 RA, TW high CLOSED LCU 26.02.2007 (RA)
final impedance of TDI 03.02.2006 AG medium TO BE FOLLOWED UP
compare collimator bench measurements with HFSS simulation 08.07.2005 AG low ON HOLD, OR TO BE FOLLOWED U P
compare the size of the longitudinal geometric wake with RW longitudinal wake from A. Koschik 28.01.2005 FR medium TO BE FOLLOWED UP

electron-cloud effects (mostly incoherent)

action date in charge priority status
discuss MAD-X e-cloud module with Frank Schmidt 05.12.2006 FZ high PLANNED
discuss US-LARP contribution to incoherent e-cloud studies with Wolfram Fischer (and Mauro Pivi) 05.12.2006 OB high PLANNED
organize meeting with L. Tavian and write a note on e- cloud 03.02.2006 FR, FZ et al high Meeting with L. Tavian DONE 17.02.2006 by FR, note PLANNED
review or prediction of incoherent electron-cloud effects in the LHC. 11.11.2005 FZ, EB-> GR high PLANNED, task reassigned 03.02.2006
prediction of beam lifetime and emittance growth as a function of density for the LHC and SPS based on HEADTAIL simulations for a dipole field 10.06.2005 EB -> GR, FZ high Task re-assigned 03.02.2006, DONE for LHC by EB on 03.03.2006


action date in charge priority status
simulate conditions of SPS compensation experiment(s) 08.07.2005 UD high ONGOING
estimate stabilization by beam-beam for injection conditions 24.06.2005 WH medium CALCULATIONS DONE (LCU 26.02.2007), DOCUMENTATION PLANNED


action date in charge priority status
review predicted and simulated emittance growth, e.g., for the CERN PS 05.12.2006 EM, FZ high PLANNED
repeat AD Experiment in Simulations (GR) 26.09.2006 GR high IN PROGRESS
simulate effect of SPS collimator on growth rate vs. chromaticity for different energies 26.09.2006 GR high IN PROGRESS
SPS e-cloud simulations at 26 and 60 GeV for a dipole field 05.05.2006 GR high IN PROGRESS
GR and FR will follow-up ideas on debunching transverse impedance measurements with GA, ES, and FZ 10.03.2006 GR, FR medium PLANNED
structured list of intensity limits for CERN and GSI 03.02.2006 FR et al high DONE for CERN, LUMI'06 (GA) and web site

fundamental questions

action date in charge priority status
derive general formula for longitudinal resistive-wall impedance 19.05.2006 EM, +student medium PLANNED
attempt to derive a general nonlinear theory including the inductive bypass 18.03.2005 EM low PLANNED, plan to recruit Ph.D. student
review Landau-damping mechanisms 13.10.2004 EM, FZ very low PENDING

Completed RLC Actions

action date in charge priority status
add 2003 minutes and presentations to the RLC web site 17.03.2006 FZ medium DONE, fall 2006
scaling of the effective LHC collimator impedance as a function of the collimator gap, bunch length & bunch spacing emails by FR,  27.04.2006 and 08.05.2006 EM, FZ, GR high DONE by EM and FZ. EM presented results at LTC 6.12.2006
contact Trevor for help with impedance calculations 07.11.2006 OB high DONE, 21.11.2006
organize team meeting on impedance database plans 07.11.2006 WH medium DONE, 21.11.2006
check definitions of transverse impedance with J. Tuckmantel and possibly B. Zotter 03.03.2006 FZ high DONE, email exchange with J. Tuckmantel, inconclusive
develop a lattice for crab cavity option 03.03.2006 RT, FZ high DONE, presented at LUMI'06
perform e-cloud simulations for the two SPS working points. 11.11.2005 EB->FZ,GR,GF high PLANNED , task reassigned 03.02.2006, DONE by GF and EB in summer 2006
compute longitudinal impedance for an IPM model 17.05.2005 AG high DONE, 10.03.2006
provide WH and HB with information for activity presentations in general group meeting 28.09.2006 12.09.2006 All high DONE, 28.09.2006
contact Bruno Spataro and/or Derun Li for Y-Chamber MAFIA input files  07.11.2006 EM high DONE, 28.11.2006
provide OB with information on US LARP 12.09.2006 All involved high DONE, 22.09.2006 meeting with Hermann Schmickler
Review of Stupakov paper 07.11.2006 EM low DONE, 21.11.2006
TDI: Inform ABMB & Brennan about need of rf fingers; check gap with Ralph 19.09.2006 OB and EM high DONE, 26.09.2006
send code questionanire to Tom Roberts for g4beamline 19.09.2006 FZ high DONE, 20.09.2006
Clarify differences in Hereward & M-S dispersion relations? 07.07.2006 EM? medium DONE, 19.09.2006
TDI follow up: gap requirements, operation mode, heating, no of units w/o ferrites & spares 12.09.2006 EM high DONE, 19.09.2006
contact rf group for possibly higher-quality bunch profiles 05.05.2006 GR, FZ high DONE, APC 18.05.2006
contact Stefano Redaelli to clarify number of TCTV 17.03.2006 EM, AG highest DONE, 07.04.2006
short note on the TCDS impedance estimates that can be referenced to in the Functional Specifications 07.04.2006 AG high DONE, 05.05.2006
include all contributions to the broad band impedance in the stability diagram both at injection and at top energy 07.04.2006 EM high DONE, 21.04.2006
inform collimation team that a gap of 12 mm is needed for
two devices and 30 mm in case of more than 2 devices
17.03.2006 FR highest DONE, 17.03.2006
contact GA and/or Bruno Spataro to clarify whether
high Q's of these modes include effect of a load
10.03.2006 GR high DONE 17.03.2006
collect existing literature on resistive coatings by FC, check scaling and the damping required for half of nominal LHC intensity, and clarify logics for correct reply to IPM team. 10.03.2006 EM, AG high DONE 17.03.2006
HFSS simulations for tertiary collimators 18.11.2005 AG high ALMOST DONE, 03.02.2006; DONE 17.03.2006
develop theory for 2-beam resistive-wall wake field 17.02.2006 FZ high DONE 03.03.2006
inform Warner Bruns about suspected bug in GdfidL 17.02.2006 AG very high DONE, 17.02.2006
inform Manfred Mayer of TCTV changes suggested 17.02.2006 AG very high DONE, 17.02.2006
produce plot comparing theoretical prediction with transverse collimator impedance inferred from FC&TK's measurement, taking into account driving and detuning wakes 03.02.2006 FZ high DONE by EM and FZ, 10.02.2006
obtain access to FC for TDI wire measurement 03.02.2006 AG via LB (FR) high DONE, 10.02.2006 by AG (email)
send email to D. Macina on TOTEM Roman Pots 03.02.2006 FR very high DONE, 06.02.2006
literature search for 2-beam wake fields 18.11.2005 EM, FZ high COMPLETED, 16.12.2005
check exact timing of bunches at TCTV and TCLIs 18.11.2005 RA high DONE by SR and AG 13.01.2006
tentative conclusion for PS kicker impedance limiting cases 18.11.2005 EM high DONE, PRESENTATION by EM 20.01.2006
stability limit for Cu secondary collimators 18.11.2005 EM medium 1ST ESTIMATE DONE 01.12.2005, final  2nd ESTIMATE 03.02.2006
check adequacy of conducting boundary conditions for HEADTAIL simulations 18.11.2005 GR medium PARTLY DONE 01.12.2005 COMPLETED 20.01.2006
discussion of the SPS single-bunch electron-cloud instability and incoherent effects scaling with energy in reply to ES. 11.11.2005 FZ high COMPLETED, 18.11.2005
clarify the offset at the first turn and the offset at which beam loss occurs for SPS fast vertical instability 14.10.2005 EM medium COMPLETED, 21.10.2005
follow up optics with beta*=2 m with LOC team and experiment 03.06.2005 WH medium COMPLETED, 23.09.2005
extract transverse impedance from bench measurement data 08.07.2005 FZ high COMPLETED, 15.07.2005
compare and understand the different predictions of the Burov-Lebedev theory calculated by FZ and EM. 13.05.2005 EM, FZ high COMPLETED, 17.06.2005 (only question mark which remains is Piwinski theory, FZ - SOLVED 26.08.2005)
produce a plot of HT growth rates as a function of
chromaticity at injection energy for nominal current
10.06.2005 EM, FZ highest COMPLETED, 17.06.2005 (one further cross check will be done by FZ for coupled-bunch growth rates
analytical/numerical estimate of the slot impedance for TCDS & TCDQ 10.06.2005 AG, EM high COMPLETED, 17.06.2005 (no hardware change will be requested)


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FZ or FR, 21 October, 2005