EIC Users Meeting 6/25/2014 The MEIC Design at Jefferson Laboratory Fulvia Pilat for the MEIC Study...
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Transcript of EIC Users Meeting 6/25/2014 The MEIC Design at Jefferson Laboratory Fulvia Pilat for the MEIC Study...
EIC Users Meeting 6/25/2014
The MEIC Design atJefferson Laboratory
Fulvia Pilat for the MEIC Study Group
EIC Users Meeting
Stony Brook, June 24-27, 2014
EIC Users Meeting 6/25/2014
Context and updates
The MEIC strategy and base of design have not significantly changed in 3+yearsThe “Science Requirements and Conceptual Design for a polarized MEIC at JLAB” published in 2012Augmented the JLAB EIC study Group with additional external collaborationsResolved many of the design challenges, working on resolving remaining onesWorking to support the NSAC process
MEIC design strategy towards high luminosity and polarization (the full scope of EIC is consistent with an upgrade of the MEIC)
High level status of the design, R&D and remaining challenges
Vision and steps towards a Conceptual Design Report (CDR)
Conclusions and outlook
Outline
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EIC Users Meeting 6/25/2014
arXiv:1209.0757
Table of ContentsExecutive Summary
1. Introduction
2. Nuclear Physics with MEIC
3. Baseline Design and Luminosity Concept
4. Electron Complex
5. Ion Complex
6. Electron Cooling
7. Interaction Regions
8. Outlook
MEIC Design Report Released
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EIC Users Meeting 6/25/2014
MEIC Study Group
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EIC Users Meeting 6/25/2014
MEIC Design Goals
EnergyFull coverage of √s from 15 to 70 GeVElectrons 3-12 GeV, protons 20-100 GeV, ions 12-40 GeV/u
Ion speciesPolarized light ions: p, d, 3He, and possibly LiUn-polarized light to heavy ions up to A above 200 (Au, Pb)
At least 2 detectors Full acceptance is critical for the primary detector
LuminosityAbove 1033 cm-2s-1 per IP in a broad CM energy rangeMaximum luminosity >1034 optimized to be around √s=45 GeV
PolarizationAt IP: longitudinal for both beams, transverse for ions onlyAll polarizations >70%
Upgrade to higher energies and luminosity possible20 GeV electron, 250 GeV proton, and 100 GeV/u ion
Design goals consistent with the White Paper requirements
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EIC Users Meeting 6/25/2014
MEIC Layout
Warm large booster(3 to 25 GeV/c)
Warm electron collider ring (3-12 GeV) Medium-energy IPs with
horizontal beam crossing
Injector
12 GeV CEBAF
Pre-booster
SRF linac
Ionsource
Cold ion collider ring (25 -100 GeV)
Three Figure-8 rings stacked vertically
IP IP
Ion Sourc
e
Pre-booster
Linac
12 GeV CEBAF
12 GeV
11 GeV
Full Energy EIC Collider rings
MEIC collider rings
Three compact rings:•3 to 12 GeV electron•Up to 25 GeV/c proton (warm)•Up to 100 GeV/c proton (cold)
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EIC Users Meeting 6/25/2014
CEBAF Commissioning
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EIC Users Meeting 6/25/2014
EIC Users Meeting 6/25/2014
Design Strategy for: High Luminosity
The MEIC design concept for high luminosity is based on high bunch repetition rate CW colliding beams
Beam Design• High repetition rate• Low bunch charge • Short bunch length• Small emittance
IR Design• Small β*• Crab crossing
Damping• Synchrotron radiation
• Electron cooling
“Traditional” hadrons colliders Small number of bunches Small collision frequency f Large bunch charge n1 and n2
Long bunch length Large beta-star
yyx
nnf
nnfL
*21
**21 ~
4
KEK-B already reached above 2x1034 /cm2/s
Linac-Ring colliders•Large beam-beam parameter for the electron beam•Need to maintain high polarized electron current •High energy/current ERL
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EIC Users Meeting 6/25/2014
Design strategy for High Polarization
All rings have a figure-8 shape with critical advantages for both ion and electron beam Spin precessions in the left & right parts of the ring are exactly cancelled Net spin precession (spin tune) is zero, thus energy independent Spin is easily controlled and stabilized by small solenoids or other compact spin rotators
Advantage 1: Ion spin preservation during acceleration
Ensures spin preservation Avoids energy-dependent spin sensitivity for all species of ions Allows a high polarization for all light ion beams
Advantage 2: Ease of spin manipulation • Delivering desired polarization at multiple collision points
Advantage 3: The only practical way to accommodate polarized deuterons(ultra small g-2)
Advantage 4: Strong reduction of quantum depolarization thanks to the energy independent spin tune
This helps to preserve polarization of the electron beam continuously injected from CEBAF
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EIC Users Meeting 6/25/2014
• Ring-Ring with CEBAF as a full energy polarized injector
• Avoids a class of challenging technology R&D (i.e. high current polarized electron source, high energy high current ERL)
• 12 GeV CEBAF source/injector already meets the requirements
• Delivers high luminosity and high polarization
Key design choices
We took some conservative technical choices:
• Limit key design parameters (beam-beam and space charge parameters) within or close to the present state-of-art
• Maximum peak field: SC dipole < 6 T; warm dipole: <1.6 T
• Maximum synchrotron radiation power density at 20 kW/m
• Manageable final focusing: maximum beta at the final focus quads is 2.5 km
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EIC Users Meeting 6/25/2014
Detector Full Acceptance Large AcceptanceProton Electron Proton Electron
Beam energy GeV 60 5 60 5
Collision frequency MHz 750 750 750 750
Particles per bunch 1010 0.416 2.5 0.416 2.5
Beam Current A 0.5 3 0.5 3
Polarization > 70% ~ 80% > 70% ~ 80%
Energy spread 10-4 ~ 3 7.1 ~ 3 7.1
RMS bunch length cm 1 0.75 1 0.75
Horizontal emittance, normalized µm rad 0.35 54 0.35 54
Vertical emittance, normalized µm rad 0.07 11 0.07 11
Horizontal and vertical β* cm 10 and 2 10 and 2 4 and 0.8 4 and 0.8
Vertical beam-beam tune shift 0.014 0.03 0.014 0.03
Laslett tune shift 0.06 Very small 0.06 Very small
Distance from IP to 1st FF quad m 7 (down)3.5 (up)
3 4.5 (down)3.5 (up)
3
Luminosity per IP, 1033 cm-2s-1 5.6 14.2
Nominal Design Parameters
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EIC Users Meeting 6/25/2014
MEIC/EIC e-A luminosity
13
EICMEIC
EIC Users Meeting 6/25/2014
MEIC/EIC e- P Luminosity
A. Accardi
EICMEIC
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EIC Users Meeting 6/25/2014
MEIC systems
Ion injector Conventional technology, detailed simulations needed should not present an issue
Ion pre-booster Ion large booster Ion collider ring • Optimization of non-linear dynamics
correction started• Encouraging initial simulation results • New collaborations on Correction and DA
initiated
Electron collider ring Interaction regions
Polarization Preliminary spin tracking of figure 8 OK
Cooling Circulator design
Transfer lines, synchronization Recent work after EICAC
Overview of MEIC design and R&D
15
Critical MEIC R&D Status Talk
High current ERL and circulator Conceptual design, e-cooling simulations done
High charge/current magnetized e-source 2 options (thermionic gun or RF photo-cathode gun)
Ultra fast kicker RF harmonic kicker concept (JLAB LDRD)
Crab cavity New cavity design developed at ODU
E ring RF system R&D in progress at JLAB SRF
EIC Users Meeting 6/25/2014
Ion Source Prototypes & Parameters
Electron-Cyclotron Resonance Ion Source (ECR)
Universal Atomic Beam Polarized Ion Sources (ABPIS)
Electron Beam Ion source (EBIS)
Polarized light Ions
Non-Polarized Ions
Ions Source Type
Pulse Width (µs)
Rep. Rate (Hz)
Pulsed current (mA)
Ions/pulse (1010)
Polarization (Pz)
Emittance (90%) (π·mm·mrad)
Note
H-/D- ABPIS 500 5 4 (10) 1000 >90% (95) 1.0 / 1.8 (1.2)
H-/D- ABPIS 500 5 150 / 60 40000/15000 0 1.8
3He++ ABPIS-RX 500 5 1 200 70% 1
3He++ EBIS 10 to 40 5 1 5 (1) 70% 1 BNL
6Li+++ ABPIS 500 5 0.1 20 70% 1
Pb30+ EBIS 10 5 1.3 (1.6) 0.3 (0.5) 0 1 BNL
Au32+ EBIS 10 to 40 5 1.4 (1.7) 0.27 (0.34) 0 1 BNL
Pb30+ ECR 500 5 0.5 0.5 (1) 0 1
Au32+ ECR 500 5 10.5 0.4 (0.6) 0 1
• Numbers in red are “realistic extrapolation for future”; numbers in blue are “performance requirements of BNL EBIS
• MEIC ion sources rely on existing and matured technologies• Design parameters are within the state-of-the-art
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EIC Users Meeting 6/25/2014
Ion Linac
Parameters Unit Value
Species p to lead
Reference Design 208Pb
Kinetic energy MeV/u 100
Max. pulse current Light ions (A/q≤3) Heavy ions (A/q≥3)
mAmA
2
0.5
Pulse repetition rate Hz 10
Pulse length ms 0.25
Max. beam pulsed power kW 680
Fundament frequency MHz 115
Total length M 150
SuperconductingNormal
conductingQWR
HWR
• Pulsed linac, peak power 680 kW
• Consists of quarter wave and half wave resonators
• Originally developed at ANL as a heavy-ion driver accelerator for Rare Isotope Beam Facility
• Adopted for MEIC ion linac because: • Satisfies MEIC ion linac requirements• Covers similar energies, variety of ion species• Excellent and mature design
• All subsystems are either commercially available or based on well-developed technologies
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EIC Users Meeting 6/25/2014
Ion Pre-boosterPurpose of pre-booster
• Accumulation of ions injected from linac• Acceleration of ions• Extraction and transfer of ions to the large
booster
Design ConceptsFigure-8 shape(Quasi-independent) modular design
• FODO arcs for simplicity and ease optics corrections
Design constraints• Maximum bending field: 1.5 T• Maximum quad field gradient: 20 T/m• Momentum compaction smaller than 1/25• Maximum beta functions less than 35 m• Maximum full beam size less than 2.5 cm, • 5m dispersion-free sections for RF, cooling,
collimation and extraction.
18
Inje
cti
on
Arc
1
Str
aig
ht
1
Arc
3
Str
aig
ht
2
Arc
2
EIC Users Meeting 6/25/2014
200
0
200
200
0
200
5
0
5
MEIC Ion Large Booster• Accelerates protons from 3 to 25 GeV (and ion energies with similar magnetic rigidity)• Follow electron/ion collider ring footprints, housed in same tunnel• Made of warm magnets and warm RF
• No transition energy crossing (always below γt=25.03)
• Quadrupole based dispersion suppression.• Tunable to any working point.
• Vertical chicane to bring low energy ions to the plane of the electron ring
• Add electron cooling and SRF
• Share detector with MEIC
IP
Possible to convert the large booster to
a low energy collider ring
19
EIC Users Meeting 6/25/2014
Lattice design of geometrically-matched collider rings completed
Detector requirements fully satisfied
Collider Ring and IR Layout
20
IPs
e-
ions
e-
ions
IP
EIC Users Meeting 6/25/2014
Detector Region Design
21
Fully-integrated detector and interaction region satisfyingX Detector requirements: full acceptance and
high resolutionX Beam dynamics requirements: consistent
with non-linear dynamics requirementsX Geometric constraints:
matched collider ring footprints
far forwardfar forwardhadron detectionhadron detectionlow-Q2
electron detectionelectron detection large-apertureelectron quads
small-diameterelectron quads
central detectorcentral detector with endcaps
ion quads
50 mrad beam(crab) crossing angle
n,
ep
p
small anglesmall anglehadron detectionhadron detection
~60 mrad bend
(from GEANT4)
2 Tm 2 Tm dipoledipole
EndcapEndcap Ion quadrupolesIon quadrupoles
Electron quadrupolesElectron quadrupoles
1 m1 m11 m m
IP FP
Roman potsRoman potsThin exit Thin exit windowswindows
Fixed Fixed trackers in trackers in vacuum?vacuum?
Trackers and “donut” calorimeterTrackers and “donut” calorimeter
RICH+
TORCH?
dual-solenoid in common cryostat4 m coil
barrel DIRC + TOF
EM
ca
lori
met
er
EM calorimeter
Tracking
EM
ca
lori
met
er
e/π
th
res
ho
ldC
he
ren
ko
v
EIC Users Meeting 6/25/2014
MEIC Ion Collider Ring
R = 90.4 m
Arc, 2400
IPs
Long straight
Dog Leg #1
Dog Leg #2
Dog Leg #1
Dog Leg #2Detector elements
CCB/dispersion suppressorArc CCB
Arc CCB
Arc CCB
Arc CCB
FODO-cell arcs
CCB in arcs for local chromaticity correction
Vertical doglegs to bring ions to electron plane
X With horizontal bendX Dispersion suppression
22
Circumference m 1415.3
arc radius / length m 90.4 / 414.90
Long straight m 292.77
Max x/y functions m 2301 / 2450
Betatron tunes (x, y) 25(.79) / 26(.27)
Chromatisities x,y (2 IR) -224 / -233
Momentum compaction 10-3 5.76
Transition gamma tr 13.2
Norm. emittancesx,y m 0.35 / 0.07
EIC Users Meeting 6/25/2014
MEIC Electron Collider RingFlat ring, defines geometry
FODO-cell arcs
All-energy Universal Spin Rotators (USR)
CCB in straights for chromaticity correction
23
Circumference m 1415.9
arc radius / length m 90.4 / 445.34
Long straight m 262.61
Max x/y functions m 769 / 842
Betatron tunes (x, y) 56(.65) / 52(.89)
Chromatisities x,y (2 IR) -204 / -203
Momentum compaction 10-3 0.76
Transition gamma tr 36.2
Norm. emittancesx,y m 53.5 / 10.7
R = 90.4 m
Arc 445m, 2400
USR, 13.2 , 54m
IPs
USR, 13.2 , 54m
USR, 13.2 , 54m USR, 13.2 , 54m
CCB
Forward e- detection
CCB Long straight
EIC Users Meeting 6/25/2014
Change the harmonic number of the ion beam at discrete energies (harmonic jump)Employ two 10 cm path length chicanes (one per arc) between jumps
10 regular 3 m long arc dipoles per chicaneThe green dipoles are regular arc dipoles with fixed bending anglesThe bending of the outer and inner red dipoles is adjusted to change the path length
FeaturesX Provides coverage of the full energy rangeX Automatic synchronization of both IP’s with two chicanes for even number of ion bunchesX Requires total additional space of < 20 m (green dipoles are already a part of the arc)X No closed orbit shift (shift the design orbit instead), no SRF frequency change,
no CEBAF synchronization issue (electron frequency is fixed), no R&D requiredX Need to evaluate the engineering challenge of moving cold magnets by up to 50 cm
Beam Synchronization
24
x = 42.6 cm
x = -53.8 cm
Total bending angle and z length are fixed
EIC Users Meeting 6/25/2014
Design requirements– High polarization (~80%) of protons and light ions (d, 3He++, and possibly 6Li+++)– Both longitudinal and transverse polarization orientations available at all IP’s– Spin flipping (through the source)
Figure-8 structure as a solution– No preferred periodic spin direction, energy-independent zero spin tune Polarization can be controlled by small magnetic fields– Eliminates depolarization problem during acceleration– Works for all ion species including deuterons
Acceleration and spin matching– Polarization is stabilized by weak (< 3 Tm) solenoids– Injection and extraction from straight with solenoid
Polarization control in the collider ring– Beam is injected longitudinally polarized, accelerated and
then the desired spin orientation is adjusted– Weak solenoids for deuterons (< 1.5 Tm each)– Weak radial-field dipoles for protons (< 0.25 Tm each)– Small or no orbit excursions, easy magnet field ramp
Ion Polarization
25
EIC Users Meeting 6/25/2014
Design requirements– High polarization (>80%) and sufficient life time– Longitudinal polarization at all interaction points– Spin flipping (through the source) at required
frequencies
Highly vertically polarized electron beam is injected from CEBAF
Polarization is vertical in the arc to avoid spin diffusion
Universal spin rotator rotates polarization from vertical
to longitudinal at IP
Spin flipping through the source
Compton polarimeters to measure polarization
Continuous injection is considered to maintain high polarization at higher energies
Figure 8 structure removes electron spin tune energy dependence
Electron Polarization
26
arc
dipolearc dipole
Solenoid 1
Solenoid 2
α2≈4.4º α1≈8.8º
spin
φ1
e-
φ2spin
Lost or Extracted
P0 (>Pt)
Pt
EIC Users Meeting 6/25/2014
Multi-Staged e-Cooling Scheme
ion sources
SRF Linac
pre-booster (3 GeV)(accumulation)
large booster (25 GeV)
medium energy collider ring
High Energy cooling
DC cooling
Stage Ion (GeV/u) Electron (MeV)
Cooling beam /Cooler
Pre-booster
Assisting accumulation of positive ions
0.1 (injection) long bunches
0.59 DC
Initial cooling to reduce emittance
3 (extraction)long bunches
2.1 DC
Collider ring
Initial cooling for emittance reduction
25 (injection) long bunches
13Bunched
/ERL
Final cooling for emittance reduction
Up to 100 bunched beam
55Bunched
/ERL
During collision (suppress IBS)
Up to 100 bunched beam, 1 cm
55Bunched
/ERL
state-of-the-art
27
EIC Users Meeting 6/25/2014
Cooling Technology Staging
The “ready-to-build” version utilizes only (loosely speaking) existing and established accelerator technologies
Proton/ion Energy (GeV/u)
Ready-to-Build
Ultimate
Pre-booster DC electron cooling to assist accumulation of positive ions
0.1
DC electron cooling for emittance reduction
3
Collider ring ERL-based electron cooling at injection energy for emittance reduction
25 (option)
ERL-based electron cooling at top energy for emittance reduction
Up to 100 “Weak”
ERL-based electron cooling during collision to suppress IBS
Up to 100 “Weak”
Stochastic cooling of heavy ions during collision to suppress IBS
Up to 100
Luminosity 1033 1/cm2/s 1 ~ 3 5.6 ~ 14
28
EIC Users Meeting 6/25/2014
Luminosity at different cooling stagesL
um
ino
sity
(10
33 1
/cm
2/s
)
Add “weak” electron cooling & stochastic cooling (heavy ions) during collision
Add 3 GeV DC cooling at pre-booster
Low energy DC cooling only at pre-
booster injection
Full capacity electron cooling (ERL-circulator cooler)
~0.41 ~1.1
~3.3
5.6
Based on existing technologies
EICAC recommendation
29
EIC Users Meeting 6/25/2014
Jefferson Lab plans to have a comprehensive Conceptual Design Report in 2-3 years
Resources: Manpower:
Given competing priorities MEIC design and R&D have operated at the 5-6 FTE level at JLAB plus leveraged collaborations
The end of 12 GeV Project accelerator scope (12 GeV experiment till 2017 and the integration of FEL personnel in Accelerator and Engineering significantly increased manpower in 2014
Pursuing new collaborations
MEIC Design and R&D funding:
NP grants (mainly towards supporting 3 post-docs)
Commonwealth of Virginia funding
LDRD (fast kicker R&D)
SBIR (Tech-X)
JLAB Accelerator R&D funds
Plans towards CDR
30
EIC Users Meeting 6/25/2014
A preliminary (“not ready for review” ) cost estimate for MEIC was carried out in 2012
A task force to issue a cost estimate for MEIC has been appointed at JLAB in January 2014 and is working now. The task force includes senior management from the 12 GeV Project, the Accelerator and Engineering Divisions, with support from the Project Management Group.
A comprehensive MEIC WBS to level 5
Baseline (Base of estimate) – June 2014
Engineering study - July 2014
Cost estimate – September-October 2014
Plan for cost estimate
31
EIC Users Meeting 6/25/2014
Towards a Conceptual Design Report
Detector R&D
Report on High Energy Electron Cooling
Report on Beam Polarization DesignA
ccel
erat
or R
&D
Report on Detector /IR Design Studies
Existing Design Report
Design Optimization
MEIC Conceptual
Design Report
2MeV DC Cooler Technical Design Report
32
EIC Users Meeting 6/25/2014
Accelerator Team & Current Collaboration
Core team (CASA): A. Bogacz, Y. Derbenev, D. Douglas, R. Li, R. Kazimi, G. Krafft, F. Lin, V. Morozov, Y. Roblin, M.Spata, C. Tennant, M. Tiefenback,
H. Zhang, Y. Zhang, students (C-Y Tsai , A. Castilla)
RF systems: F. Hannon, R. Rimmer, H. Wang, S. Wang (SRF R&D, Jlab)
RF Fast Kicker: A. Kimber (Engineering), C. Tennant LDRD
High current un-polarized e-source: R. Suleiman (Source, Jlab)
Interaction regions: M. Sullivan (SLAC)
Polarization: A. Kondratenko (Novosibirsk), D. Barber (DESY)
Low energy ion complex: linac: P. Ostroumov (Argonne Lab) pre-booster: B. Erdelyi (Northern Illinois Univ.)
Beam-beam simulation: J. Qiang (LBL)
Cooling Simulation: I. Pogorelov (Tech-X) SBIR
Nonlinear corrections, DA: D. Trbojevic, Y. Jing, Y. Luo (BNL) U. Wienands, Y. Nosochkov (SLAC)
33
EIC Users Meeting 6/25/2014
Tasks assignments for Accelerator R&D towards CDR
ResponsibilityCore MEIC team High energy electron cooling
ERL-Circulator cooler developmentCollider rings and boosters designInteraction region designElectron polarizationInstabilities and collective effectsFast beam kicker
JLab internal collaboration Electron ring RF (SRF/Rimmer)Cooler demo (FEL/Douglas)
External collaboration (out-sourcing)
2D DC electron cooler technical designStochastic coolingIon polarization Ion sourcesIon linac (update)Low energy ion beam formationDetector backgroundNonlinear corrections, DA
To be determined Magnetized electron photo-cathode gun
34
EIC Users Meeting 6/25/2014
The MEIC design fulfills the requirements for high luminosity and polarization needed by the nuclear physics community
We have a mature strategy and design and a very significant progress has been achieved on technical challenges in the last 3 years
We need to:
Demonstrate the remaining open technical issues with studies, modeling and a strategic and collaborative R&D program
Strengthen further the Design Team at Jefferson Lab as well as widen the external collaboration
Secure R&D funding commensurate with the stated goals
We believe we can deliver a comprehensive Conceptual Design Review in 2-3 years
Conclusions and outlook
35
EIC Users Meeting 6/25/2014
Backup Slides
36
EIC Users Meeting 6/25/2014
electron beams with high polarization are injected from CEBAF– avoid spin decoherence, simplify spin transport from CEBAF to MEIC, alleviate the detector background
Polarization is designed to be vertical in the arc to avoid spin diffusion and longitudinal at collision points using spin rotators
A Universal spin rotator rotates the electron polarization from 3 to 12GeV
spin flipping is implemented by changing the source polarization
A Compton polarimeter is considered for polarization measurements Two long opposite polarized bunch trains (instead of alternate polarization between bunches) simplify the Compton polarimetry
The figure-8 geometry removes electron spin dependence on energy
Continuous injection of electron bunch trains from the CEBAF is envisioned to preserve and/or replenish the electron polarization, especially at higher energies, and
maintain a constant beam current in the collider ring
Spin matching in some key regions is considered if it is necessary
Electron polarization
37
… …… …
Empty buckets Empty buckets1.33ns
748.5MHz
Polarization (Up) Polarization (Down)
bunch train & polarization pattern in the collider ring
EIC Users Meeting 6/25/2014
Why a magnetized electron cooler?
With the cathode immersed in a solenoid, the gun generates an almost parallel (laminar) beam state of a large size
– Larmor circles very small compared to the beam size
This state is then transported to the solenoid in the cooling section – Conserves the canonical emittances
The solenoid field is chosen to make the electron beam size match properly the ion beam size
Magnetization results in the following critical advantages
(compared to a non-magnetized gun):
Large reduction (by two orders of value) of (local and global) space charge
Improves the dynamics in CCR (tune shift, micro-bunching)
Strong suppression of CSR micro-bunching/ energy spread growth
Limits reduction of cooling rates due to high electron transverse velocity spread and short-wave misalignments
– Ion collides with “frozen” electrons
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EIC Users Meeting 6/25/2014
Continuous injection principle
Note that:– Continuous injection mainly considered at higher energies– A relatively low averaged beam current of tens-of-nA level – Constant beam current maintained
On possible injection bunch pattern
Continuous Injection Technique
39
Lost or Extracted
P0 (>Pt)
Pt
10 )1(
injdk
ringrevequ I
ITPP
……
1.33 ns, 748.5 MHz 2.4 pC
2.3μs, ~1700 bunches2.4 pC
1.33 ns, 748.5 MHz
2.3μs, ~1700 bunches
……
……
1 ms
Iave = 59 nA 140 ms
EIC Users Meeting 6/25/2014
Detector Type Full Acceptance High Luminosity
Proton Electron Proton Electron
Beam energy GeV 100 5 100 5
Collision frequency MHz 748.5 748.5 748.5 748.5
Particles per bunch 1010 0.42 2.5 0.42 2.5
Beam Current A 0.5 3 0.5 3
Polarization ~ 80% > 80% ~ 80% > 80%
RMS bunch length cm 1 0.75 1 0.75
Energy spread 10-4 ~ 3 7.1 ~ 3 7.1
Normalized emittance, x/y µm rad 0.4 / 0.04 54 / 5.4 0.4 / 0.04 54 / 5.4
Horizontal and vertical β* cm 10 / 2 10 / 2 8 / 0.8 5.5 / 0.55
Beam-beam tune shift, x/y 0.014 0.03 0.014 0.03
Laslett tune shift 0.03 < 0.001 0.03 < 0.001
Distance from IP to 1st FF quad m7 (downstream)3.5 (upstream)
34.5 (downstream)3.5 (upstream)
3
Luminosity per IP, 1033 cm-2s-1 8.3 21
MEIC Nominal Parameters at Design Point 100X5 GeV2
40EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Detector Type Full Acceptance High Luminosity
Proton Electron Proton Electron
Beam energy GeV 50 5 50 5
Collision frequency MHz 748.5 748.5 748.5 748.5
Particles per bunch 1010 0.21 2.2 0.21 2.2
Beam Current A 0.25 2.6 0.25 2.6
Polarization ~ 80% > 80% ~ 80% > 80%
RMS bunch length cm 1 0.75 1 0.75
Energy spread 10-4 ~ 3 7.1 ~ 3 7.1
Normalized emittance, x/y µm rad 0.3 / 0.06 54 / 5.4 0.3 / 0.06 54 / 5.4
Horizontal and vertical β* cm 10 / 2 10 / 2 4 / 0.8 4.1 / 0.82
Beam-beam tune shift, x/y 0.015 0.014 0.015 0.014
Laslett tune shift 0.053 < 0.0005 0.053 < 0.0005
Distance from IP to 1st FF quad m7 (downstream)3.5 (upstream)
34.5 (downstream)3.5 (upstream)
3
Luminosity per IP, 1033 cm-2s-1 2.4 6.0
MEIC Nominal Parameters at Design Point 50X5 GeV2
41EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Detector Type Full Acceptance High Luminosity
Lead Electron Lead Electron
Beam energy GeV 40 5 40 5
Collision frequency MHz 748.5 748.5 748.5 748.5
Ions/electrons per bunch 1010 0.005 2.5 0.005 2.5
Beam Current A 0.5 3 0.5 3
Polarization -- > 80% -- > 80%
RMS bunch length cm 1 0.75 1 0.75
Energy spread 10-4 ~ 3 7.1 ~ 3 7.1
Normalized emittance, x/y µm rad 0.3 / 0.1 54 / 5.4 0.3 / 0.1 54 / 5.4
Horizontal and vertical β* cm 10 / 2 10 / 2 8 / 0.8 5.5 / 0.55
Beam-beam tune shift, x/y 0.006 0.025 0.006 0.025
Laslett tune shift 0.044 < 0.001 0.044 < 0.001
Distance from IP to 1st FF quad m7 (downstream)3.5 (upstream)
34.5 (downstream)3.5 (upstream)
3
Luminosity per nucleon-IP, 1033 cm-2s-1 11.3 28
MEIC Nominal Parameters for Lead Ion at Design Point 40X5 GeV2
42EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014 43EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Item FY16 FY17 FY18 FY19 FY201. Optimize Research through Increased Weeks of Operation 6 3 3 7 7
Power/Cryogens 2.4 1.6 1.5 2.2 2.3Staffing to support 4-Hall operation 3.0 4.1 3.7 4.7 4.1Experimental Capital Equipment 0.5 0.8 1.3 2.3 2.3
Sub Total 5.9 6.5 6.5 9.2 8.7
• Reduce Risk of Major Disruptions in Machine and Experimental Hall Operations Spare Compressor for CHL-2 1.0 Spare C100 Cryomodule 1.0 1.5 0.5 End Station Refrigerator Upgrade/Replacement 0.5 0.5 0.5 0.5 0.5
CHL 1&2 Cold Compressor Controls 1.0 0.5 Sub Total 2.5 3.0 1.5 0.5 0.5
• Advance MEIC Research and Development 3.1 3.8 3.0 2.0 2.0
Sub Total 3.1 3.8 3.0 2.0 2.0
• Sustainability 4.0 3.0 2.0
MIE – MOLLER Experiment 4.7 10.7 6.2 0.7 LQCD / SciDAC – estimated funding based on discussion w/HEP/ONP 1.0 1.4 1.2 1.2 1.2
Priorities for Optimizing Scientific Output FY16-20(M$)
44EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Universal Spin Rotator
• Rotating spin from vertical to longitudinal• Consists of 2 solenoids & 2 (fixed angle) arc dipoles• Universal
energy independent
works for all energies (3 to 12 GeV)
orbit independent
does not affect orbital geometry
Compensation of solenoid x-y coupling
arc
dipolearc
dipole
Solenoid 1
Solenoid 2
α2≈4.4º α1≈8.8º
spin
φ1 Electron
beamφ2spin
17.90320
Tue Jul 13 23:59:50 2010 OptiM - MAIN: - C:\Working\ELIC\MEIC\Optics\5GeV Electe. Ring\sol_rot_2.opt
15
0
1-1
BE
TA_
X&
Y[m
]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
solenoid 4.16 m
decoupling quad insert
solenoid 4.16 m
V. Livinenko & A. Zholents, 1980
E (GeV)
1 BL1 (Tm)
1 2 BL2 (Tm)
2
3 /2 15.7 /3 0 0 /6
6 0.62 12.3 2/3 1.91 38.2 /3
9 /6 15.7 2/3 62.8 /2
12 0.62 24.6 4/3 1.91 76.4 2/3
45EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Proton/He-3 Polarization at IPs
IIP
IP
• Three Siberian snakes, both in horizontal-axis• Vertical polarization direction periodic• Spin tune: 1/2
IIP
IPVertical
longitudinal • Two Siberian snake, with their parameters set at specific values. Spin tune: 1/2
Three Siberian snakes, all longitudinal-axis
Third snake in straight is for spin tune
Spin tune: 1/2
Case 1: Longitudinal Proton Polarization at IP’s
Case 2: Transverse proton polarization at IP’s
Case 3: Longitudinal & transverse proton polarization on two straights
IIP
IP
longitudinal axis
Vertical axis
axis in special angle
46EICAC Meeting 2/28/14
EIC Users Meeting 6/25/2014
Deuteron Polarizations at IPs
Stable spin orientation can be controlled by magnetic inserts providing small spin rotation around certain axis and shifting spin tune sufficiently away from 0
Polarization is stable as long as additional spin rotation exceeds perturbations of spin motion
Polarization direction controlled in one of two straights
Longitudinal polarization in a straight by inserting solenoid(s) in that straight
Case 1: Longitudinal Deuteron Polarization at IP’s
IP
IIP
Solenoid
IP
IIP
Insertion
Case 2: Transverse Deuteron Polarization at IP’s
• Magnetic insert(s) in straight(s) rotating spin by relatively small angle around vertical axis (A. Kondratenko)
47EICAC Meeting 2/28/14