PPT Future High Energy Physics Accelerators under Studies

Introduction to CEPS-SppC Design Status

J. Gao

IHEP, CAS, China

Future High Energy Particle Colliders in China

Contents

1. Introduction 2. CEPC

3. SppC

4. Concluding remarks

Lepton and Hadron Colliders’ History

BEPC II LC

BEPC

History of BEPC

CEPC+SppC

CEPC: Ecm=240GeV e+e- Circular Collider SppC: Ecm=50-100TeV pp Collider

HIEPAF : High Intensity Electron

Positron Accelerator Facility

Strategy on High Energy Colliders in China

• On “The 464

Fragrant Hill Meeting”, Chinese High Energy Physics Community arrived at the following consensus:

1) China supports ILC and will participate to ILC construction

with in-kind contributions and requests R&D fund from government

2) After the discovery of Higgs, as next collider after BEPCII in China, a circular e+e- Higgs factory （ CEPC ） and a Super proton-

proton Collier (SppC) afterwards in the same tunnel is an important option and historical opportunity.

• On “The third China High Energy Physics based on Particle Accelerators”, Feb.

28, it was concluded that:“Circular e+e- Circular Higgs Factory(CEPC) +Super

pp Collider (SppC) is the first choice for China’s future high energy physics

accelerator.

CEPC-SppC Organization

Institutional Board Y.N. Gao (TU)

J. Gao (IHEP)

Steering Committee

Y.F. Wang(IHEP) , Y.N. Gao (TU), J. Gao (IHEP), X.C. Lou (IHEP), Q. Qin (IHEP), H.J. Yang (SJTU)

， L. Han (USTC), S. Jin (IHEP), H.J. He (TU), S.H. Zhu (PKU), Y.J. Mao (PKU)

Project Directors X.C. Lou(IHEP) Q. Qin (IHEP)

Detector Accelerator

Theroy

Internationalization

• This is a machine for the world and by the world: not a Chinese one

• As a first step, “Center for Future High Energy Physics (CFHEP)” is established

– Prof. Nima Arkani-Hamed is now the director

– Many theorists(coordinated by Nima and Tao Han) and accelerator

physicists(coordinated by Weiren Chou) from all the world have signed to work at CFHEP from weeks to months.

– More are welcome  need support from the related management – Current work:

• Workshops, seminars, public lectures, working sessions, …

• Pre-CDR

– Future works (with the expansion of CFHEP)

• CDR & TDR

• Engineer design and construction

– A seed for an international lab 

Organized and managed by the community

• We established closely collaborate with

FCC@CERN

A Good Start

Many workshops, seminars in China and in the world

– Sep. 2013, Dec. 2013, March. 2014, Oct.

2014…

CEPC-SppC and FCC

• CERN started the Future Circular Collider effort since last year

• FCC kick-off meting in Feb., 2014

• ICFA statement On Feb. 21, 2014 at DESY ：

ICFA supports studies of energy frontier circular colliders and encourages global coordination

ICFA: international committee for Future accelerators

http://www.fnal.gov/directorate/icfa/

Preliminary Conceptual Design Report of CEPC-SppC

Writing assigned for Pre-CDR (for example)

4 CEPC - accelerator physics

4.1 Main parameters Guo Yuanyuan, Geng Huiping, Wang Dou, Xiao Ming, Gao Jie

4.2 Lattice Geng Huiping, Wang Dou, Guo Yuanyuan, Wang Na, Wang

Yiwei, Xiao Ming, Peng Yuemei, Bai Sha, Su Feng, Xu Gang

, Duan Zhe, Gao Jie

4.3 IR and MDI Wang Dou, Geng Huiping, Wang Yiwei, Bai Sha, , Gao Jie

4.4 Beam instability Wang Na, Wang Yiwei

4.5 Beam-beam effects Zhang Yuan, Guo Yuanyuan, Wang Dou, Xiao Ming, Gao Jie

4.6 Synchrotron radiation Ma Zhongjian, Geng Huiping 4.7 Injection and beam dump Cui Xiaohao, Su Feng, Xu Gang

4.8 Background Yue Teng

4.9 Polarization Duan Zhe

 Visitors from other labs in the world participate the Pre-CDR

joint works

Visitors from April – May, 2014 to IHEP

Visitors name Period Topics

Dick Talman April 13th –May 15th Parameters and other topics Armen Apyan April 1st –April 30th GuineaPig and CAIN

Yoshihiro Funakoshi April 1st-April 15th Parameter, injection and others Dmitry Shatilov April 1st- April 16th Beam-beam simulation

Kazuhito Ohmi April 16th-April 30th Beam-beam simulation

Yunhai Cai April 16th –April 30th Lattice and FFS

Indico for CEPC AP meeting

http://indico.ihep.ac.cn/categoryDisplay.py?categId=237

DocDB system for documents management



Contents

1. Introduction 2. CEPC

3. SppC

4. Concluding remarks

Parameter Unit Value Parameter Unit Value

Beam energy [E] GeV 120 Circumference [C] km 50.0

Number of IP[N

] 　 2 SR loss/turn [U

] GeV 2.96

Bunch number/beam[n

] 　 50 Bunch population [Ne] 　 3.52E+11

SR power/beam [P] MW 50 Beam current [I] mA 16.89

Bending radius [] m 6200 momentum compaction factor [

] 　 4.00E-05 Revolution period [T

] s 1.67E-04 Revolution frequency [f

] Hz 5995.85

emittance (x/y) nm 6.9/0.021 

(x/y) mm 800/1.2

Transverse size (x/y) m 74.30/0.16 

/IP 　 0.097/0.069

Beam length SR [

] mm 2.12 Beam length total [

] mm 2.42 Lifetime due to

Beamstrahlung min 80 lifetime due to radiative Bhabha

scattering [

] min 53.98

RF voltage [V

] GV 6.87 RF frequency [f

] GHz 0.7

Harmonic number [h] 　 116747 Synchrotron oscillation tune [

] 　 0.196 Energy acceptance RF [h] % 5.71 Damping partition number [J] 　 2 Energy spread SR [

] % 0.13 Energy spread BS [

] % 0.07

Energy spread total [

] % 0.15 n

　 0.21

Main parameters for CEPC

Sketch of CEPC

In current design:

• Circumference: 51.6 km

• 16*arcs: 48.4km

• 14*short straight: 14*144m=2.0km

• 2*IPs:2*576m=1.2km

 8 RF cavities are uniformly

distributed in every other straights.

 The other 6 straights can be used

for injection and dump.

Lattice of arc sections

 Length of FODO cell: 48m

 Phase advance of FODO

 Dispersion suppressor on

each side of every arc

Lattice of straight sections

 Length straight: 144m

 Phase advance of FODO cells: 60/60 degrees

 FFS is temporarily replaced by FODO cells

 Length of each IP section: 576m

 Used for workpoint adjustment

Dynamic aperture of the MR

 2 families of sextupoles are used for chromaticity correction

 Working point of the ring (.08,.22)

 Achieved dynamic aperture ： ~100

/1500

Pretzel scheme

 Use 2 pairs of electrostatic separators

 Beam separated at horizontal plane with orbit offset of 5

 Maximum bunch number: 96

Original FFS design by Dou WANG

IP

Total length: 670 m

betaX*=0.8m

betaY*=0.0012m

L*=2.5m

Half Quad of

dispersion suppressor IP

FFS entrance condition:

DX=DPX=0 x=y=0 betax=84m betaY=28m

Newest FFS design based on Yunhai’s idea

betaX*=0.8m betaY*=0.0012m L*=2.5m

• We use the same method as Yunhai’s example to make a new design of CEPC FFS.

Total length: 170 m

Maximum pole strength for different length

Lattice of whole ring

Dynamic Aperture-FFS 170m

(Zero sextupole length)

On momentum



0 . 0 0 3

0 . 0 0 2

0 . 0 0 1 0 . 0 0 0 0 . 0 0 1 0 . 0 0 2 0 . 0 0 3 X  m  1 .

1 0

7

2 .

1 0

7 3 .

1 0

7 4 .

1 0

7 5 .

1 0

7 6 .

1 0

Y 7  m 

Dynamic Aperture-FFS 170m

(finite sextupole length)

On momentum

Off

momentum:

2%,  1%

FFS:170m

L=0.3m

ε

=7.67nm ε

=ε

/330=0.0232nm βx=0.8m βy=0.0012m

σx=78 μm σy = 0.167 μm

10.8σy

On momentum 2%,-2%

0

Dynamic Aperture-FFS 170m

FFS 670m

Dynamic Aperture-FFS 970m

CEPC Beam-beam simulation (Ohmi’s)

The current main

parameters has been

checked with beam-beam simulation, proved the reasonability.

It seems bety~2mm better

than 1.2mm from luminosity

and transverse distribution

Tune diagram of CEPC lattice

According to Ohmi’s simulation results, we choose the Work

point: (179.08, 179.22)

Primary calculations for Synchrotron Radiation Parameters at CEPC ring

– The radiated critical photon energy

– The flux density at the forward (direction(photons/s/mr2/0.1%bandwidth)

– The total emitted power in each bending magnet

2 2

[ ] 0.665 [ ] [ ] 0.665*120 *0.07 670.32

c

keV E GeV B T

keV

   

2 2

[ ] 1.27

[ ] [ ] [ ] [ ] 27.55 P kW  E GeV B T I A l m  kW

2 13 2

0 2

2

1.33 10

[ ] [ ] ( /

)

d F E GeV I A H

d

   



2 2

2

( )

( / 2) H y  y K y

: 16.9[ ]

For CEPC I  mA

Synchrotron Radiation at CEPC

– Synchrotron Radiation Parameters calculated

– realizable shielding structure design for the beam pipe can be critical

• LEP vacuum chamber structure was adopted preliminary

– Shielding model and method were important

• Simulation programs: FLUKA &

MCNP

• Model building and simulation were independently for

verification

– Primary shielding simulating results focus on

CEPC bending magnet synchrotron

radiation brightness

CEPC undulator and wiggler synchrotron

radiation brightness

CEPC Magnets’ specifications

Symbol Value

Frequency(MHz) f

700

Voltage(GV) V

6.87

Cavity Numbers N

433

Synchrotron phase(deg) φ

154.01

Power/cavity (kW) P

　 231

RF power(MW) P

108

Klystron Numbers (1MW ) N

109

Operating temperature(K) T 2

Quality factor (10

) Q

2

R/Q (Ω) R/Q 470

Total loss on cavity(kW) P

11.08

2K heat load(kW) W

14.1

Parameters Related to RF System

Cavity design

Frequency(MHz) f

700

Gradient(MV/m) E

15MV/m

Operating voltage Vc 15.885MV

Cell NO. N

5

Effective length Lc 1059mm

Equator diameter(mm) D 386.2

Iris diameter (mm) r

150 Module length(m) L

7 Module NO.

(4 cavities/ module) N

109

R/Q(Ω) R/Q 492.904

Quality factor (2K) Q

Q

=2*10

RF coupler Q

Q

2.22*10

RF System Distribution

 Total number of module: 109

• 4 cavities/module, 7m/module

• Total length: 7m*109=763m

 8 RF districts

• 14module/district*5+13module/district*3

• Length of district: 98m&91m

 Klystron number:109

CEPC RF System Cryogenic Loss

Beam current (mA) 16.60

P_c / cavity (W) 25.6

P_c (kW) 11.08

P_HOM / cavity (kW) 4.9

P_{HOM total} (MW) 2.1

SR power(MW/2 beam) 100

RF-beam power efficiency 95%

RF source efficiency 65%

2K efficiency W/W 700

5K efficiency W/W 200

80K efficiency W/W 16

Cryogenic safty factor 1.5

2K AC power (MW) 14.8

5K AC power (MW) 1.1

80K AC power (MW cold HOM absorber) 50.8 80K heat load (MW)

(HOM coupler and warm absorber) 0.1 Cryogenic AC power (MW)

(cold HOM absorber scheme) 67

Cryogenic AC power (MW)

(HOM coupler and warm absorber scheme) 16

RF AC power (MW) 165.2

Total AC power(MW cold absorber) 232.2 Total AC power(MW warm absorber) 181.2

CEPC four 5-cell 700 MHz cavity string (moderate technical challenge):

• HOM coupler (modes below cut-off

frequency < ~ kW; or larger beam pipe, no cut-off); extra

cryogenic load to be calculated.

• HOM damper at room temperature (4.9 kW each damper); HOM damper at 80-100 K (forbidden by

cryogenics load: 80 K

cryo efficiency 16

W/W)

CEPC Multi Bunch Effects

Longitudinal τ

=0.007s

Transverse τ

=0.014s

Mode TM011 TE111 TM110

f(MHz) 1175.7 917.6 1040.7

R/Q 146.0Ω 1.0Ω/cm

2.7Ω/cm

Qe 1000 1000 1000

Ztot 0.06GΩ 0.2GΩ/m 0.5 GΩ/m

Z

8.58GΩ 3.02GΩ/m 3.02GΩ/m

Requirement Qe<10

Qe<10

No instability issues. There is no heavy instabilities if Q

<10

. Need both cold

Impedance budget

• Resistive wall impedance is calculated with analytical formulas

• Impedance of the RF cavities is calculated with ABCI

Object Contributions

R [k] L [nH] k

[V/pC] |Z

/n|

[]

Resistive wall (Al) 16.8 214.4 552.1 0.0075

RF cavities (N=378)

40.1 -- 1313.6 ---

Total 56.9 214.4 1865.7 0.0075

) ( )

( )

( s Rc s Lc

s

W      

-10 -5 0 5 10

-2000 -1000 0 1000 2000

z, mm

wake, V/pC

beam RW RF

Single-bunch effects

Parameter Symbol, unit Value

Beam energy E, GeV 120

Circumference C, km 53.6

Beam current I

, mA 16.6

Bunch number n

50

Natural bunch length 

, mm 2.58

Emittance (horz./vert.) 

/

, nm 6.79/0.02

RF frequency f

, GHz 0.7

Harmonic number h 125208

Natural energy spread 

1.5E3

Momentum compaction factor 

4.15E5

Betatron tune 

/

179.08/179.22

Pseudo-Green function wake (z=0.5mm)

-2 -1 0 1 2

-20000 -15000 -10000 -5000 0 5000

z, mm

wake, V/pC

beam wakeL

-5 0 5

0 5 10 15x 10¹⁰

z/z

Beam line density (a.u.) no wake with wake

Steady-state bunch shape

• Longitudinal microwave instability

– Keil-Schnell criterion:

– The threshold of the longitudinal

impedance is |Z

/n| < 0.026 .

l e p

th

n R Z

e E I

|

|

2   





• Space charge tune shif

• Coherent synchrotron radiation

 



/h

=35.2 (=> CSR shielded)

– The threshold of bunch population for CSR is given by

– The CSR threshold in BAPS is N

= 1.510

>> N

= 3.710

. – CSR is not supposed to be a problem in BAPS.

2 / 3

2 / 1 3

/ 4 3 / 1

2 , h

N

S r

z s

b

e

 















 



 0. 50 0 . 12 S

(K. Bane, Y. Cai, G. Stupakov, PRST-AB, 2010)

 





 ds

s s

s N s

r

y

x

( )( ( ) ( ))

) ( )

2 (

, 3

2 /

, 3

  







 

• Transverse mode coupling instability (TMCI)

– The threshold of transverse impedance is |Z

| < 11.7 M/m.

– The equivalent longitudinal impedance is 0.18 , which is much larger than that of the longitudinal instability.



 







 R eI Z Eb

b

4

• Eigen mode analysis

• Considering only resistive wall impedance

• Beam current threshold:

I

=0.76mA (I

=38mA)

0 0.2 0.4 0.6 0.8 1

-3 -2 -1 0 1 2

Ib, mA (- )/ s

Multi-bunch effects

• Transverse resistive wall instability

with 

= 2  f

 (pn

+ n + 

)





 









p

pn y

x b

b

e Z

e E

c I

n

) (

) Re / ( 4

1

,

 













 The growth rate for the most dangerous instability mode is 36 Hz (=28 ms) in the vertical plane with mode number of  = 21.

 The growth time is higher than the transverse radiation damping time.

 The resistive wall instability is not

-20 -10 0 10 20 30 40





(21, 36.1)

Electron cloud instability

KEKB SuperKEKB SuperB CEPC

Beam energy E, GeV 3.5 4.0 6.7 120

Circumference L, m 3016 3016 1370 53600

Number of e

/bunch, 10

3.3 9 5.74 37.1

Emittance H/V 

/ 

, nm 18/0.36 3.2/0.01 1.6/0.004 6.79/0.02

Bunch length 

, mm 4 6 5 2.58

Bunch space Lsp, ns 2 4 4 3575.8

Single bunch effect

Electron freq. 

/2, GHz 35.1 150 272 191.4

Phase angle 



/c 2.94 18.8 28.5 10.4

Threshold density 

, 10

m

0.7 0.27 0.4 1.15

Multi-bunch effect

p-e per meter n

, p/(m) 5.0E8 1.5E9 3.6E9 1.1E10

Characteristic frequency 

, MHz 62.83 87.2 69.6 5.92

Phase angle 

L

/c 0.13 0.35 0.28 21.2

• Threshold density for the single bunch effect is considerable high.

• The phase angle for the multi-bunch effect is about two orders higher, so the

electrons are not supposed to accumulate and the multipacting effects is low.

Beam ion instability

• Ion trapping

– With uniform filling pattern, the ions with a relative molecular mass larger than A

will be trapped.

• Fast beam ion instability

– With uniform filling, the growth time considering ion

oscillation frequency spread is 11ms, which is lower than the damping time.

– Fast beam ion instability could occur with uniform filling.

y x y x

b p b y

x

S r A N

, ,

 2 (    ) 

2 / 1 2 / 1 2 2 /

3

c

– The ions will not be trapped by the beam.

0 0.5 1 1.5 2 2.5

x 10⁴ 0

0.5 1 1.5 2 2.5

3x 10⁴

z, m A x/A y

X: 1.077e+004 Y: 421.5

Ax Ay

Beam lifetimes caused by different sources in CEPC

 Quantum lifetime

 Radiation Bhabha lifetime

 Simulated by BBBREM



 q   i  e 

2  q  

min 98

.

 53

 RBB

Beam lifetimes caused by different sources in CEPC

 Beam-gas lifetime

 Touschek lifetime

) )(

, (

10 47

. 3 1 .

1    

p m

Torr hour

dt

dN

g

N

 

g  10 3 h



 

 



     













 



   



 

















) )(

2 ln

3 2 ( 1 ln

2 2

) 3 ( 1 ,

8

) ( 1

2 3 2

U dU dU e

Ue e U

D D c

 Nr

U rf U

l y x e tou

CEPC Layout

LTB : Linac to Booster

BTC : Booster to Collider Ring BTC

IP1

IP2

e+ e-

e+ e- Linac (240m)

LTB

CEPC Collider Ring(50Km)

Booster(50Km)

BTC

Booster bypass design

Booster: Outer of Collider Collider

CEPC CEPC

The outer-ring bypass computation

BYPASS:

BYPASS:

BPO1 , -DIS, DIS, BPO2

RING :

RING : IP1, -BPI, -ARC1, -STR, 6*SUP, ARC1, BPI, IP2,

IP2, -BPI, -ARC1, -STR, 6*SUP, ARC1, BPI, IP1

CEPC Injection Scheme

1. Betatron Injection

2.Two Kicker Bumps

Linac 240m 6GeV

Injection and beam dump

Booster 6GeV-120GeV

Main Ring 120GeV Rumping time (rump up/rump down) about 10s L decrease 10% , need reinjection(190s)

Booster and Main Ring have the same time structure

50 bunches kicker

167μs

Injection process ：

1) e+ injected from Booster to Main Ring:<167 μs 2) Booster magnets rump down : 10s

3) e- injected from Linac to Booster : 1s 4) Booster Magnets rump up : 10s

5) e- injected from booster to Main Ring:<167 μs

6) e+ Injected from Linac to Booster and rump up : (The e+ produce rate is low , so the e+ will take a longer time to be injected from the Linac to Booster . But this must be finished and get ready for the next injection before the luminosity drop 10% , maybe less than 40s.)

The total time for injrction is about 20s , while the

operation period is about 190s.

Injection linac-1

Beam energy:

E

= 6GeV

Energy Spread:

s

<110

；

Bunch population:

N

=(5%  N

)/0.9=2  10

Bunch structure:

f

= 50-100Hz, Dt=0.7 ns, Emittanch:

Depending on aperture selection of the booster. A=Y

/b

.

Y=16mm, b

=130m, A ～ 2 mmmrad, e ～ 0.05A ～ 0.1 mm 

mrad

Injection linac-2

1 、 If S-band, 6GeV

Linac length~450m

  t=0.7 ns ， single bunch

3 、 600MeV produce positron ， positron bunch charge 1nC?

6GeV Conventional Linac

Electron Source-1

• Unpolarized Conventional Electron Source

N

=(5% N

)/0.9=210

f

= 50-100Hz, t=0.7 ns,

Parameter Unit

Type Thermionic Triode Gun

Cathode Y824 (Eimac) Dispenser

Beam Current (max.) A 6.0

High Voltage of Anode kV 150 ~ 200

Bias Voltage of Grid V 0 ~ -200

Pulse duration 0.7 ns Single Bunch

Repetition Rate Hz 50-100

Electron Source-2

• Unpolarized Conventional Electron Source

0 10 20 30 40 50 60 70 80 90 100

0 10 20 30 40 50 60 70

R (mm)

Z (mm) 18.1KV/mm

13.9KV/mm -200KV

 High Voltage = 150 kV

 Beam Radius ~ 3.0mm (at gun anode, beam current is 6.0A)

BII Electron Gun

Positron Source-1

• Unpolarized Positron Source

Conventional Positron Source

 Electron energy at Target 600MeV?

 Electron beam at Target 240MeV, 8A

 Positron beam 80mA For BII

For CEPC

Positron Source-2

• Polarized Positron Source (R&D)

 Compton scattering based polarized positron source

1. Polarization for positron is very difficult.

2. Both scheme are very challenging.

3. Choose some key technologies R&D

Contents

1. Introduction 2. CEPC

3. SppC

Parameter LHC HL-LHC HE-LHC FCC-hh SppC Unit Main parameters

Circumference 26.7 26.7 26.7 100/83 50 km

Beam energy 7 7 16.5 50 31.7 TeV

Lorentz gamma 7459 7459 17581 53277 33779

Dipole field 8.33 8.33 20 16/20 20 T

Dipole curvature radius 5280.8 m

Arc filling factor 0.79 0.79 0.79 0.79 0.79

Total dipole magnet length 33180 m

Arc length 42000 m

Total straight section length 4224 4224 4224 16800 8000 m

Energy gain factor in collider rings 15

Injection energy 0.45 0.45 〉1.0 3.3 2.1 TeV

Number of IPs 2+2 2

Revolution frequency 11.26 11.26 11.26 3 6 kHz

Main Parameter List for SppC (version 1)

By Valkovich, Xiao Ming, Su Feng, Gao Jie, Tang Jingyu, Chou Weiren

2014.05.09

Physics performance and beam parameters LHC HL-LHC HE-LHC FCC-hh SppC Units

Peak luminosity per IP 1.0E34 5.0E34 5.0E34 5.0E34 1.2E+35 cm^-2s^-1

Beta function at collision 0.55 0.15 0.35 1.1 0.75 m

Circulating beam current 0.584 1.12 0.478 0.5 1.0 A

Number of IPs contributing to ΔQ 3 2 2 2 2

Max total beam-beam tune shift ΔQ 0.01 0.015 0.01 0.01 0.015？

Max beam-beam tune shift per IP 0.005 0.0075 0.005 0.005 0.0075?

Bunch separation 25 25 25 25

5 25 ns

Number of bunches

2808 2808 2808 10600（890

0） 53000（4450

0）

5333

Bunch population 1.15E11 2.2E11 1.0E11 1.0E11 2.0E+11

Normalized rms transverse emittance 3.75 2.5 1.38 2.2 3.3 mm

Beam life time due to burn-off 45 15.4 5.7 19.1/15.9 8.7 hour

Total / inelastic cross section 111/85 111/85 129/93 153/108 140 mbarn

Reduction factor in luminosity（F） 0.85

Full crossing angle 285 590 185 74 139 mrad

rms bunch length 75.5 75.5 75.5 80/75.5 75.5 mm

rms IP spot size 16.7 7.1 5.2 6.8 8.5 mm

Beta at the 1st parasitic encounter 19.5 m

rms spot size at the 1st parasitic encounter 43.3 mm

Stored energy per beam 0.392 0.694 0.701 8.4/7.0 5.4 GJ

SR power per ring 0.0036 0.0073 0.0962 2.4/2.9 1.5 MW

Beam-beam tune shift limit calculations

 

max

2845

6

p

IP

r

f x RN

 

 

t dt x

f

x

 





0

2

2 ) 2 exp(

1 2 )

( 

IP p

IP

r N

R x

f N

x

x f 





6 2845

) ( 4 )

(

4

max

2

 

03656 .

 2 x

0417 .

0 )

( x  f

0064 .

max

 0



For lepton collider:

For hadron collider:

where

SppC (actual parameter list)

FCC (pp) 0.005 (theory and design)

Formulae from private note of J. Gao

IP e

RN r



 max  6

1

 2845 r_e is electron radius

γ= is normalized energy R is the dipole bending radius

N_IP is number of interaction points

r_p is proton radius

SppC Layout

Medium Energy Booster(4.5Km) Low Energy Booster(0.4Km)

IP4 Proton Linac IP3

(100m) High Energy Booster(7.2Km)

SppC injector complex-1

(Yuhong Zhang)

High Energy Booster Medium Energy

Booster Proton Linac

Low Energy Booster

Peak Energy

(GeV)

Energy boosting (E

/E

)

Dipole

field (T) Circumference

(km) Length/Radius (m)

Electron linac 6 240

Proton linac 1 100

Low energy booster 16 16 0.1 

1.6 0.4 64

Medium energy

booster 250 15.6 0.1 

1.6 4.5 (7.2) 716(1146)

High energy booster 3000 12 1  12 7.2 1146

Collider ring 35000 11.7 1.7  20 50 7962

SppC injector complex-2

(Jingyu Tang,2014.06.05)

Peak Energy

(GeV)

Energy boosting (E

/E

)

Circumference

(km) Length/Radius (m)

Electron linac 6 240

Proton linac 1 300

Low energy booster 14 14 1.2 191

Medium energy booster 200 14.3 3.5 573

Some main parameters for the injector complex-2

Value Unit

Superconducting Linac

Energy 1.0 GeV

Average current 0.7 mA

Length ~300 m

Repetition rate 50 Hz

Beam power 0.7 MW

LEB

Energy 14 GeV

Average current 0.07 mA

Circumference 1200 m

Repetition rate 25 Hz

Beam power 1.0 MW

MEB

Energy 200 GeV

Average current 21 uA

Length 3500 m

Repetition rate 0.5 Hz

Beam power 4.2 MW

HEB

Energy 2.1 TeV

Accumulated protons 5.3E14

Circumference 7000 m

Repetition period 20 S

Protons per bunch 2.0E11

Dipole field 8 T

CEPC-SppC Schedule (Preliminary)

• CPEC

– Pre-study, R&D and preparation work

• Pre-study: 2013-15  Pre-CDR by 2014

• R&D: 2016-2020

• Engineering Design: 2015-2020

– Construction: 2021-2027 – Data taking: 2030-2036

• SPPC

– Pre-study, R&D and preparation work

• Pre-study: 2013-2020

• R&D: 2020-2030

• Engineering Design: 2030-2035

– Construction: 2036-2042

CEPC-SppC Layout

LTB : Linac to Booster

BTC : Booster to Collider Ring BTC

IP1

IP2

e+ e-

e+ e- Linac (240m)

LTB

CEPC Collider Ring(50Km

)

Booster(50Km

)

Medium Energy Booster(4.5Km) BTC

Low Energy Booster(0.4Km)

IP4 IP3

SppC Collider Ring(50Km)

Proton Linac (100m) High Energy Booster(7.2Km)

Contents

1. Introduction 2. CEPC

3. SppC

Concluding remarks

1. CEPC-SppC is the first choice of future high energy collider in China

2. The organizing and task forces for CEPC-SppC have been established

3. Pre-CDR for CEPC-and SppC is on the mid-way with progresses, and will be finished at the end of 2014

4. There are still many works to do in order to a good design 5. Collaboration between CEPC-SppC and FCC(ee,hh) has been established

6. International participation and collaboration are warmly

welcome

Acknowledgements

1. Thanks to program committee to invite me to give this talk 2. Many thanks to my colleagues for their hard works and

providing me necessary materials and useful discussions