PS (electron cloud?!) instability at flat top Mauro Pivi Gianni Iadarola, Giovanni Rumolo, Simone Gilardoni, Hannes Bartosik, Sandra Aumon 27/06/2012 ICE.

Slides:



Advertisements
Similar presentations
Electron-cloud instability in the CLIC damping ring for positrons H. Bartosik, G. Iadarola, Y. Papaphilippou, G. Rumolo TWIICE workshop, TWIICE.
Advertisements

Damping ring K. Ohmi LC Layout Single tunnel Circumference 6.7 km Energy 5 GeV 2 km 35 km.
E-Cloud Effects in the Proposed CERN PS2 Synchrotron M. Venturini, M. Furman, and J-L Vay (LBNL) ECLOUD10 Workshshop, Oct Cornell University Work.
Preliminary results and ideas for the SPS upgrade MDs on LHC beams in 2011 G. Rumolo on behalf of all the MD team (Elena, Thomas, Karel, Christina, Holger,
SPS scrubbing run in 2014 H. Bartosik, G. Iadarola, G. Rumolo LHC Performance Workshop (Chamonix 2014), 22/9/2014 Many thanks to: G. Arduini, T. Argyropoulos,
Elias Métral, 1st ICE meeting, 14/07/2010 /191 STATUS OF THE LHC INSTABILITIES E. Métral, N. Mounet and B. Salvant E. Métral, N. Mounet and B. Salvant.
Giovanni Rumolo, G. Iadarola and O. Dominguez in LHC Beam Operation workshop - Evian 2011, 13 December 2011 For all LHC data shown (or referred to) in.
Simulations on the EC detector in MU98 A. Romano, G. Iadarola, G. Rumolo LIU-PS Meeting 28 April 2015 Many thanks to: M. Taborelli, C. Yin Vallgren.
March 2, 2007ELC Experience with clearing voltages and solenoids at SPS damper pick-ups W. Hofle Acknowledgements PS-OP, SL-OP, SL-BI LHC-VAC, SL-HRF.
AB-ABP/LHC Injector Synchrotrons Section CERN, Giovanni Rumolo 1 Final results of the E-Cloud Instability MDs at the SPS (26 and 55 GeV/c) G.
SPS scrubbing experience: electron cloud observables L. Mether on behalf of the LIU-SPS e-cloud team LIU SPS scrubbing review, September 8, 2015.
H. Bartosik, K. Cornelis, A. Guerrero, B. Mikulek, G. Rumolo, Y. Papaphilippou, B. Salvant, E. Shaposhnikova June 16 th, 2011.
G. Rumolo, G. Iadarola, H. Bartosik, G. Arduini for CMAC#6, 16 August 2012 Many thanks to: V. Baglin, G. Bregliozzi, S. Claudet, O. Dominguez, J. Esteban-
Elias Métral, APC meeting, 02/02/2006 1/35 E. Métral, G. Arduini and G. Rumolo u Observations of fast instabilities in the SPS (1988 and 2002/3) and PS.
Collected by E. Jensen, BE-RF 1 ATOP days RF limitations.
Managed by UT-Battelle for the Department of Energy Analysis of 2008 Beam Instability Data S. Cousineau, V. Danilov, M. Plum HB2008.
Simulations and measurements of the injection oscillations and the MTE A. Huschauer Supervisor: S. Gilardoni Acknowledgements: H. Bartosik, H. Damerau,
0 1 Alternative Options in the Injectors – Preliminary Summary H. Damerau LIU-TM#8 18 October 2013 Many thanks for discussions and input to T. Argyropoulos,
PS (electron cloud?!) instability at flat top Mauro Pivi Gianni Iadarola, Giovanni Rumolo, Simone Gilardoni 05/06/2012 LIU-PS meeting, CERN.
Update of the SPS transverse impedance model C. Zannini, G. Rumolo, B. Salvant Acknowledgments: H. Bartosik, O.Berrig, F. Caspers, E. Chapochnikova, G.
Elias Métral, LHC Beam Commissioning Working Group meeting, 08/06/2010 /191 SINGLE-BUNCH INSTABILITY STUDIES IN THE LHC AT 3.5 TeV/c Elias Métral, N. Mounet.
Wolfgang Hofle BE/RFSPS Studies WG - November 17, 20091/23 reported by Wolfgang Hofle CERN BE/RF/FB Transverse feedback to cure electron-cloud induced.
Chromaticity dependence of the vertical effective impedance in the PS Chromaticity dependence of the vertical effective impedance in the PS S. Persichelli.
BEPCII Transverse Feedback System Yue Junhui Beam Instrumentation Group IHEP , Beijing.
Improved electron cloud build-up simulations with PyECLOUD G. Iadarola (1),(2), G. Rumolo (1) (1) CERN, Geneva, Switzerland, (2) Università di Napoli “Federico.
CERN, LIU-SPS ZS Review, 20/02/ Brief review on electron cloud simulations for the SPS electrostatic septum (ZS) G. Rumolo and G. Iadarola in LIU-SPS.
Elias Métral, ICFA-HB2004, Bensheim, Germany, 18-22/10/ E. Métral TRANSVERSE MODE-COUPLING INSTABILITY IN THE CERN SUPER PROTON SYNCHROTRON G. Arduini,
Heat load analysis for Inner Triplet and Stand Alone Modules H. Bartosik, J. Hulsmann, G. Iadarola and G. Rumolo LBOC meeting 28 October 2014 Based on.
Elias Métral, SPSU Study Group and Task Force on SPS Upgrade meeting, 25/03/2010 /311 TMCI Intensity Threshold for LHC Bunch(es) in the SPS u Executive.
CERN F. Ruggiero Univ. “La Sapienza”, Rome, 20–24 March 2006 Measurements, ideas, curiosities beam diagnostics and fundamental limitations to the performance.
News on TMCI in the SPS: Injecting high intensity bunches Benoit for the MD team: T. Bohl, K. Cornelis, H. Damerau, W. Hofle, E. Metral, G. Rumolo, B.
SPS proton beam for AWAKE E. Shaposhnikova 13 th AWAKE PEB Meeting With contributions from T. Argyropoulos, T. Bohl, H. Bartosik, S. Cettour.
Elias Métral, LHC Beam Commissioning Working Group meeting, 30/11/2010 /241 PRELIMINARY FINDINGS FROM INSTABILITY MEASUREMENTS DURING THE 75ns AND 50ns.
Coupled bunch instabilities in the CERN PS
LIU-SPS e-cloud contribution to TDR Electron cloud meeting, 17/02/20141 o First draft by end of February Between 5 to 10 max pages per chapter, refer.
Comparison of stainless steel and enamel clearing electrodes E. Mahner, F. Caspers, T. Kroyer Acknowledgements to G. Arduini, H. Damerau, S. Hancock, B.
Simulation of the new PS EC detector: implementation and results A. Romano, G. Iadarola, G. Rumolo LIU-PS Student Day 20 April 2015.
RF measurements during floating MD in Week 40 3 rd of October 2012 LIU-SPS BD WG 25/10/2012 Participants: T. Argyropoulos, H. Bartosik, T. Bohl, J. Esteban.
Progress on e-cloud effects (PS and SPS) G. Iadarola, H.Bartosik, G. Rumolo, M. Taborelli, C. Yin Vallgren Many thanks to: G. Arduini, T. Argyropoulos,
Feedback Simulations with Amplifier Saturation, Transient and Realistic Filtering Mauro Pivi, Claudio Rivetta, Kevin Li Webex CERN/SLAC/LBNL 13 September.
Summary of ions measurements in 2015 and priorities for 2016 studies E. Shaposhnikova 3/02/2016 Based on input from H. Bartosik, T. Bohl, B. Goddard, V.
US Dependence of e-Cloud on the Longitudinal Bunch Profile Studies in the PS & Extension to the HL-LHC C. M. Bhat Fermilab/CERN H. Damerau, S. Hancock,
Benchmarking Headtail with e-cloud observations with LHC 25ns beam H. Bartosik, W. Höfle, G. Iadarola, Y. Papaphilippou, G. Rumolo.
Longitudinal Limitations of Beams for the LHC in the CERN PS 0.
Status of the single-bunch feedback system for the SPS/LHC M. Pivi C. Rivetta, J. Cesaratto, J. Fox, O. Turgut, S. Uemuda, W. Hofle, U. Wehrle, K. Li,
AB-ABP/LHC Injector Synchrotrons Section CERN, Giovanni Rumolo 1 Preliminary results of the E-Cloud Instability MDs at the SPS G. Rumolo, in.
PS beam dynamics issues in view of LHC beams upgrade: brief status and prospects G. Rumolo (Beam Dynamics for the PSB/PS Upgrade Working Groups), based.
Juan F. Esteban Müller P. Baudrenghien, T. Mastoridis, E. Shaposhnikova, D. Valuch IPAC’14 – Acknowledgements: T. Bohl, G. Iadarola, G. Rumolo,
HEADTAIL simulation during the accelerating ramp in the PS S. Aumon - EPFL & CERN Acknowledgement to B. Salvant, G. Rumolo.
A preliminary overview on the 2014 Scrubbing Run II The scrubbing team, i.e. H. Bartosik, G. Iadarola, K. Li, L. Mether, A. Romano, G. Rumolo, B. Salvant,
LIU Day 2014 – M.Bodendorfer - LEIR model. LEIR model A plan for understanding/upgrading the LEIR performance limitations M.Bodendorfer BE/ABP & LEIR.
Beam Instability in High Energy Hadron Accelerators and its Challenge for SPPC Liu Yu Dong.
Longitudinal beam parameters and stability
e- Cloud Machine Studies-Tune Shift Studies
Proposals for 2015 impedance-related MD requests for PSB and SPS
Benchmarking the SPS transverse impedance model: headtail growth rates
MD2490: Measurement of the TMCI Threshold at Flat-Top
Multiturn extraction for PS2
Summary of Space-Charge Measurements, 2011
The SPS 800 MHz RF system E. Shaposhnikova for BE/RF
G. Arduini, R. Calaga, E. Metral, G. Papotti, G. Rumolo, B. Salvant, R
Introduction to LHC beam production in PSB and PS
W. Bartmann, M. Benedikt, E. Métral, D. Möhl, G. Rumolo and B. Salvant
News on TMCI in the SPS: Injecting high intensity bunches
Beam dynamics requirements after LS2
Observation of Transverse Mode Coupling Instability at the PS and SPS
Collective effects in the SPS and LHC (longitudinal plane)
CERN-SPS horizontal instability
2008 MDs Helmut Burkhardt, Rama Calaga, Wolfgang Hoefle, Riccardo de Maria, Elias Metral, Giulia Papotti, Giovanni Rumolo, Benoit Salvant, Bruno Spataro,
Wednesday h18: 228b fill lost just before start of ramp.
Presentation transcript:

PS (electron cloud?!) instability at flat top Mauro Pivi Gianni Iadarola, Giovanni Rumolo, Simone Gilardoni, Hannes Bartosik, Sandra Aumon 27/06/2012 ICE meeting, CERN

Previous Work [1] R. Cappi, M. Giovannozzi, E. Metral, G. Metral, G. Rumolo, and F. Zimmermann, PRST AB Volume 5, (2002) [2] Rende Steerenberg et al. APC – Meeting December (2006)

LHC beam, 25 ns bunch spacing LHC beam, 25 ns bunch spacing, 1.15 e11 ppb Removed last part of compression before extraction from PS: – 40 MHz cavity maxed up at 100kV (adiabatic compression) – 80 MHz cavity turned OFF – 11-14ns long bunch Added 35ms to obtain long flat top 27/06/2012 Mauro Pivi, ICE meeting

Nominal RF cycle 27/06/2012 Mauro Pivi, ICE meeting

RF Gymnastics in the PS with the 40 and 80 MHz Cavities 5 Nominal RF cycle What happens before the extraction of LHC beam from the PS? 80 MHz (h= 168) 40 MHz (h= 84) 4  = 14 ns 11 ns 4 ns Adiabatic shortening Bunch rotation Bunch splittings Extraction …and lots of other things: Extraction bump, synchronization, etc. Heiko Damerau

RF cycle – 40 MHz cavity ramp and added flat top RF cavity 40 MHz: measured RF Voltage ramp -- RF 40 MHz cavity -- extraction bump 27/06/2012 Mauro Pivi, ICE meeting

Measured beam at 4 different times on flat top 2419 ms2426 ms2436 ms2446 ms LHC 25 ns RF ramp to 100kV RF ramp END at 2419 ms RF cavity 40 MHz: measured RF Voltage ramp 27/06/2012 Mauro Pivi, ICE meeting

Instability measurements at longer flat top – Preview 2419 ms2426 ms2436 ms2446 ms 1.15 x ppbUNSTABLE 0.6 x ppbslightly unstable UNSTABLE 27/06/2012 Mauro Pivi, ICE meeting

Beam fill 27/06/2012 Mauro Pivi, ICE meeting

Measurement at end of RF ramp – low bam intensity Beam pick-up signals -- Wall current monitor -- Sum -- Horizontal -- Vertical Electron cloud signals: -- e- cloud pickup 1 -- e- cloud strip-line -- pressure - 0.6e11 ppb ms, RF ramp End Horizontal plane slightly unstable near end of train 2419 ms RF ramp This measurement taken at this time 27/06/2012 Mauro Pivi, ICE meeting

Measurement along flat top – Low beam intensity Bunch intensity = 0.6e11 ppb bunch length = 11.5 ns 2419 ms2426 ms2436 ms2446 ms Legend Beam Pick-up Signals: -- Horizontal -- Vertical -- Sum -- Wall current monitor RF ramp Note: electron cloud is under the radar … Legend Electron cloud pick-ups -- e- cloud pickup 1 -- e- cloud strip-line -- pressure 27/06/2012 Mauro Pivi, ICE meeting

Measurement along flat top – Nominal beam intensity 2419 ms2426 ms2436 ms2446 ms -- Sum -- Horizontal -- Vertical -- Wall current monitor RF ramp Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns electron cloud signal -- e- cloud pickup 1 -- e- cloud strip-line -- pressure 27/06/2012 Mauro Pivi, ICE meeting

Measurement along flat top – nominal beam intensity: Closer look at 2419 ms Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor RF ramp This measurement taken at: 2419 ms Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Measurement along flat top – nominal beam intensity: Closer look at 2446 ms Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor RF ramp This measurement taken at: 2446 ms Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Transverse beam profile Horizontal (mm) Bunch intensity = 1.15e11 ppb LHC beam, 25 ns bunch spacing Beam profile in the presence of instability at flat top

Instability measurements at longer flat top – Summary so far 2419 ms2426 ms2436 ms2446 ms 1.6e e11UNSTABLE 0.8e11 0.6e11slightly unstable UNSTABLE 27/06/2012 Mauro Pivi, ICE meeting

Following MD In a subsequent MD, the beam was more stable: at 2421 ms -> stable (on 10 cycles ) at 2426 ms -> threshold (11 stable/6 unstable) at 2431 ms -> unstable (1 stable 9 un-stable) As observed in 2006, the beam is not always stable/un-stable

Re-established nominal RF cycle - measuring just before extraction 2455 ms -- RF 40 MHz cavity -- extraction bump RF cavity 40 MHz: measured RF Voltage ramp Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Re-established nominal RF cycle - measuring just before extraction just before extraction, 500 turns acquisition Beam Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Re-established nominal RF cycle - measuring just before extraction just before extraction: bunch undergoes compression Beam Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor Horizontal displacement due to extraction bump? Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Re-established nominal RF cycle - measuring just before extraction just before extraction: bunch undergoes compression Beam Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor Only displacement? and why also in vertical? Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Re-established nominal RF cycle - measuring just before extraction Beam extracted Pick-up Signals: -- Horizontal -- Vertical -- Sum - Wall current monitor Bunch intensity = 1.15e11 ppb bunch length = 13.5 ns 27/06/2012 Mauro Pivi, ICE meeting

Future Plan With a long flat top: Next MD on Friday: Check with 50 ns bunch spacing and increase bunch population up to 2e11 ppb Scan chromaticity and intensity Measure tune shift as a function of bunch position in the train (positive tune shift  electron cloud sign) Nominal RF cycle More measurements to verify if there is an instability at all before extraction Need tools to analyse data 27/06/2012 Mauro Pivi, ICE meeting

Medium- and Long-Term Plan Estimate SEY in PS test chamber by PyEcloud Use the WARP (Berkeley LBNL) code in coupled- bunch mode and Head-Tail to: – Understand if it is an Electron cloud driven instability – Disentangle between coupled- or single-bunch instability If the PS suffers of an electron cloud instability, plan for countermeasures: – Feedback system – Coating of the PS 27/06/2012 Mauro Pivi, ICE meeting

Summary Measured transverse instability at flat top, LHC nominal beam and 25 ns bunch spacing Goal is to: – Understand if it is an Electron cloud instability – Estimate SEY in PS test chamber by using PyEcloud – disentangle between coupled- or single-bunch instability also by using WARP (LBNL) code With the nominal RF cycle more work is needed to understand if there is effectively an instability 27/06/2012 Mauro Pivi, ICE meeting

Data in directory: G:\Departments\BE\Projects\PSUpgrade\MDs \PSecloud_ sp?shiftId= /06/2012Mauro Pivi, LIU-PS meeting