1. IHEP Status and Future Plan
Yifang Wang
Institute of High Energy Physics
ALCW2015, April 23, 2015

2. Particle Physics in China: Unusual Support
Matter may be break up infinitely
---- Mao Zedong met Sakata Shyoichi in 1964
IHEP established at an unusual moment: Feb. 1, 1973
7 failed attempts to build a HEP accelerator in China since 50’s
Since the success of BEPC in 80’s, HEP in China started to be on a right track
New era since the completion of the upgrade of BEPC (BEPCII) in 2008.

3. Particle & Astro-Particle Physics at IHEP
Current
Future
Accelerator-based
Precision frontier
BESIII
International: ILC
CEPC  SppC
International projects:
Belle II、PANDA、COMET
Energy frontier
CMS、ATLAS
Non-accelerator-based
Underground
Daya Bay
JUNO
nEXO
EXO
Surface
ARGO/ASg
LHASSO
Space
AMS
HERD
XTP
HXMT

4. BESIII Experiment Modern detectors with excellent performance
1T SC magnet
Crystal calorimeter
Drift chamber, RPC muon chamber, TOF counters, …
Large international collaboration
~400 members from 52 institutions and 11 countries
Many interesting results
Zc(3900), Zc(4020), X(1835),…
> 70 papers
> 150 talks

5. BESIII Data Taking Status & Plan
Previous Data set
BESIII now
Goal
J/psi
BESII: 58M
1.2 B
10B
Psi’
CLEO：28 M
0.5 B 3B
Psi”
CLEO：0.8 /fb
3.0/fb
20 /fb
y(4040)/y(4160)/X(4260) etc.
CLEO：0.6/fb @ y(4160)
0.5/fb y(4040); ~4360;
~ 10 /fb
R scan & Tau
105 GeV
100K/pnts
BESIII will continue for the next 8-10 years: Unique in the world

6. The Future: CEPC+SppC
For about 8 years, we have been talking about “What can be done after BEPCII in China”
Thanks to the discovery of the low mass Higgs boson, and stimulated by ideas of Circular Higgs Factories in the world, CEPC+SppC configuration was proposed in Sep. 2012
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)
Low Energy Booster(0.4Km)
IP4
IP3
SppC Collider Ring(50Km)
Proton Linac
(100m)
High Energy Booster(7.2Km)
A km tunnel is relatively easier NOW in China

7. Scientific Goals CEPC ( e+e-: 90-250 GeV) SppC (pp: 50-100 TeV)
Higgs Factory: Precision study of Higgs(mH, JPC, couplings)
Z & W factory: precision test of SM
Flavor factory: b, c, t and QCD studies
SppC (pp: TeV)
Directly search for new physics beyond SM
Precision test of SM
e.g., h3 & h4 couplings
Three pillars: EW phase transition, naturalness, dark matter
CEPC-SppC complementary with each other

8. Timeline (dream) CPEC SppC Pre-study, R&D and preparation work
Pre-CDR for R&D funding request
R&D:
Engineering Design:
Construction:
Data taking:
SppC
Pre-study:
R&D:
Engineering Design:
Construction:
Data taking:

9. CEPC Accelerator Linac Booster 6~10 GeV Collision ring 45/120 GeV
Energy Ramp
10 ->120GeV
6~10 GeV
Electron
Linac
Booster
Positron
3 machines in one tunnel
CEPC & booster
SppC
Injectors
Compatibility issues
CEPC vs SppC
Detectors & beampipes
SR beamlines
Collision ring
45/120 GeV

10. Priliminary CEPC parameter list
Unit
Value
Beam energy [E]
GeV
120
Circumference [C] m
54752
Number of IP[NIP] 2
SR loss/turn [U0]
3.11
Bunch number/beam[nB] 50
Bunch population [Ne]
3.79E+11
SR power/beam [P] MW
51.7
Beam current [I] mA
16.6
Bending radius [r]
6094
momentum compaction factor [ap]
3.36E-05
Revolution period [T0] s
1.83E-04
Revolution frequency [f0] Hz
emittance (x/y) nm
6.12/0.018
bIP(x/y) mm
800/1.2
Transverse size (x/y)
69.97/0.15
xx,y/IP
0.118/0.083
Beam length SR [ss.SR]
2.14
Beam length total [ss.tot]
2.65
Lifetime due to Beamstrahlung (simulation)
min 47
lifetime due to radiative Bhabha scattering [tL] 52
RF voltage [Vrf] GV
6.87
RF frequency [frf]
MHz
650
Harmonic number [h]
118800
Synchrotron oscillation tune [ns]
0.18
Energy acceptance RF [h] %
5.99
Damping partition number [Je]
Energy spread SR [sd.SR]
0.132
Energy spread BS [sd.BS]
0.119
Energy spread total [sd.tot]
0.163 ng
0.23
Transverse damping time [nx]
turns 78
Longitudinal damping time [ne] 39
Hourglass factor Fh
0.658
Luminosity /IP[L]
cm-2s-1
2.04E+34

11. CEPC Detector Similar performance requirements to ILC detectors
Momentum: ← recoiled Higgs mass
Impact parameter: ← flavor tagging, BR
Jet energy: ← W/Z di-jet mass separation
Beneficial from 20 years of ILC study
ILD-like detector but (incomplete):
Shorter L* (1.5m) → constraints on space for the Si/TPC tracker
No power-pulsing → cooling issues Limited CoM (up to 250 GeV) → calorimeters of reduced size
Lower radiation background → vertex detector closer to IP …

12. Civil Construction A floor map for surface and underground facilities
Geological survey and site selection
Try to get a credible design with cost estimate
Try to keep the cost low
Utilities with power consumption estimate

13. Revisions after international reviews Can be downloaded from
March 30, 2015

14. Physics Cases Higgs studies at CEPC Precision EW tests at CEPC
Flavor physics at CEPC
Searches at SppC
Heavy ion and electron-ion collision physics
March 30, 2015

15. Current Status Pre-CDR completed R&D issues identified：
Machine design & optimization
SRF cavity fabrication & processing
Cryo. module & system design and fabrication
Beam diagnosis
Vacuum pipes & heat dissipation
SC dipole magnet for SPPC …
Seed money for R&D from IHEP
Proposal for R&D submitted
No show-stoppers for CEPC
Important for Tech. Dev. anyway
Important for CEPC
P.S.
IP1
IP4
IP3
IP2
D = 17.3 km
½ RF RF
(4 IPs, m each)
C = km

16. Complementary with ILC
Energy：
CEPC for Z and Higgs(250 GeV)
ILC can go to 500 GeV for all couplings(Htt etc)
Detector：
One detector each for ILC and CEPC . ILC can give up Push-Pull.
ILC & CEPC: cross check
Technology:
ILC can go to higher energy  FEL
CEPC can go to higher Luminosity  Synchrotron
Timeline:
ILC starts from 2020 ?
CEPC starts from 2022 ?
Why two ? One is enough ?
Two very different technology. Very different possibility for future.
Cross check：2 accelerator + 2 detector is better than 1 (ILC) + 2 detector

17. International Collaboration
Right now the pre-CDR is mainly Chinese efforts with international help
An excise for us
Build confidence for the Chinese HEP community
A new scheme of international collaboration to be explored:
Not the same as ITER, ILC, CERN, …
A new institution, a consortium, or just a new project ?
An international advisory board will be formed soon to discuss this issue and many others
Welcome suggestions

18. Particle & Astro-Particle Physics at IHEP
Current
Future
Accelerator-based
Precision frontier
BESIII
International: ILC
CEPC  SppC
International projects:
Belle II、PANDA、COMET
Energy frontier
CMS、ATLAS
Non-accelerator-based
Underground
Daya Bay
JUNO
nEXO
EXO
Surface
ARGO/ASg
LHASSO
Space
AMS
HERD
XTP
HXMT

19. Space Projects g-ray-burst detector Moon exploration HXMTME LE HE
Gamma-ray burst polarization (POLAR):

20. High Energy cosmic Radiation Detection (HERD) onboard the China’s Space Station
Science
Dark matter search: γ from 0.1 – 10,000 GeV
Spectral and composition measurements of CRs between 300 GeV to PeV
Complementary to LHAASO: directly measured composition & spectrum in space
Status
Mission concept selected
Design concept reviewed
Technical review for mission selection soon
Groups from China，Italy，Switzerland，Sweden,…
Launch in ~2023 (?)
PWO or BGO
X0(λ)
∆E/E for e
e/p sep
e GF
200GeV
p GF
HERD (2020)
55(3) 1%
10-6
3.1
2.3
Fermi (2008) 10
12%
10-3
0.9 --
AMS02 (2011) 17 2%
0.12
DAMPE (2015) 31
10-4
0.3
CREAM (2015)
20(1.5)
0.2 20

21. From ASg/ARGO to LHAASO
Cosmic-rays physics and g-ray astronomy
Altitude ~ 4400 Sichuan
International collaboration: China, France, Italy, …
Start construction: 2016 ?
2018/9/16

22. Daya Bay reactor neutrino experiment Probability of non-zero q13 5.3 s
In March 2012, Daya Bay reported the measurement:
Sin22q13 =  0.016(stat)  0.005(syst)
Probability of non-zero q s
F.P. An et al., Phys. Rev. Lett. 108, (2012)
citations ~1200

23. Next Step: Mass Hierarchy
Daya Bay
Huizhou
Lufeng
Yangjiang
Taishan
Status
running
planned
approved
Construction
construction
power/GW
17.4
18.4
Daya Bay
60 km JUNO
Previous site
Lufeng
Huizhou
Daya Bay
Current site
Hong Kong
Talk by YFW at ICFA seminar 2008, Neutel 2011; by J. Cao at NuTurn 2012 ;
Paper by L. Zhan, YFW, J. Cao, L.J. Wen, PRD78:111103,2008; PRD79:073007,2009
Taishan
Yangjiang

24. Schedule & Current Status
Civil preparation：
Civil construction：
Detector component production：
PMT production：
Detector assembly & installation：
Filling & data taking：2020
Grounding breaking on Jan. 10, 2015

26. Particle & Astro-Particle Physics at IHEP
Current
Future
Accelerator-based
Precision frontier
BESIII
International: ILC
CEPC  SppC
International projects:
Belle II、PANDA、COMET
Energy frontier
CMS、ATLAS
Non-accelerator-based
Underground
Daya Bay
JUNO
nEXO
EXO
Surface
ARGO/ASg
LHASSO
Space
AMS
HERD
XTP
HXMT