2. LIU-PS Beam Dynamics Working Group Introduction and objectives
23/08/2017
H. Damerau, A. Huschauer, A. Lasheen

3. Introduction Reliably double intensity of 25 ns spacing beam for LHC
LIU/HL-LHC projects set demanding beam parameters for the PS after LS2
Reliably double intensity of 25 ns spacing beam for LHC
Initial set of studies to define baseline upgrades, < 2014
1.4 GeV  2 GeV injection reducing space charge
RF upgrades: Local 1-turn delay and global feedbacks
2014 – 2016: Refined MD studies
Difficult to reach beam parameters with baseline upgrades
From 2016:
Ramping up studies again: MDs, simulations, impedance model
Additional ideas beyond LIU baseline to be scrutinized

4. Introduction
Objectives: LIU baseline parameters/HL-LHC request, standard
Parameter
Achieved
Injection
Intensity per bunch (total: 2 · 1013 ppp)
ppb
(12  )
Injection energy, Ekin
2.0 GeV
1.4 GeV
Transverse emittances
1.8 mm
Longitudinal emittance
3.0 eVs PS
Beam loss 5%
Transverse emittance growth
Controlled longitudinal blow-up
~50%
Space charge tune shift, DQy
-0.3
Ejection
Intensity per bunch
ppb
ppb
1.9 mm
> 2 mm
0.35
Bunch length
4 ns

5. Introduction
Objectives: LIU baseline parameters/HL-LHC request, standard
Parameter
Achieved
Injection
Intensity per bunch (total: 2 · 1013 ppp)
ppb
(12  )
Injection energy, Ekin
2.0 GeV
1.4 GeV
Transverse emittances
1.8 mm
Longitudinal emittance
3.0 eVs PS
Beam loss 5%
Transverse emittance growth
Controlled longitudinal blow-up
~50%
Space charge tune shift, DQy
-0.3
Ejection
Intensity per bunch
ppb
1.9 mm
>> 2 mm
0.35
0.45…0.5 eVs
Bunch length
4 ns
4.5…5 ns

6. Introduction Objectives: LIU baseline parameters/HL-LHC request, BCMS
Achieved
Injection
Intensity per bunch (total: 2 · 1013 ppp)
ppb
(6  )
Injection energy, Ekin
2.0 GeV
1.4 GeV
Transverse emittances
1.2 mm
Longitudinal emittance
1.5 eVs PS
Beam loss 5%
Transverse emittance growth
Controlled longitudinal blow-up
~50%
Space charge tune shift, DQy
-0.31
Ejection
Intensity per bunch
ppb
ppb
1.9 mm
~2 mm
0.35
Bunch length
4 ns

7. Objectives of the new working group
Discuss measurements, calculations and simulations for all beam dynamics issues relevant to LHC-type beams in the PS
Focus on work in progress, ongoing MD studies, e.g.,
Beam stability and bunch rotation
Space charge, sources of uncontrolled emittance growth
Large longitudinal emittance
Impedance model (longitudinal/transverse) …
Agree on priorities for further studies
Interface between beam dynamics and hardware issues
Define needs from equipment for further studies, e.g., special mode of operation for cavities or kickers
Suggest improvements and recommend their implementation
Report back to LIU-PS Coordination meeting (K. Hanke)

8. Practical issues
Meeting to take place according to needs, about four-weekly
Mixed subjects: longitudinal and transverse
3-4 short presentations per meeting
Discussions should be the most important part
Open to everybody, participation according to subjects
Please forward invitation to interested colleagues
Potential slot for regular meeting:
Tuesday, 16h00 in parallel to LIU-PSB meeting
Thursday, 10h15
Thursday, 16h00 alternating with LIU-SPS BD WG
Friday, 14h00 alternating with MSWG