Transcript CEPC-SOI-July152016x

Overview of the CEPC Project
XinChou Lou
Institute of High Energy Physics, Beijing
July 15, 2016
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Outline
HEP Program in China – a brief reminder
CEPC and SppC
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Physics
Accelerators: progress and status
The detector at the CEPC
Site and civil engineering
Other activities
International collaboration
R&D Funding
Summary
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The High Energy Physics Program
China
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Experimental Particle Physics Program
pursued by physicists in China
Neutrino
physics
Daya Bay
Underground dark matter /bb decay experiment
New
hadrons
LHC
Pandax and CEDEX
BESIII experiment
BELLEII/PANDA
ATLAS/CMS/LHCb/Alice + upgrades
Future high luminosity,
high energy accelerators
 a variety of experiments ongoing or planned
 CEPC-SppC the very long term future
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CEPC-SppC
Phase 1: e+e- Higgs (Z) factory
two detectors, 1M ZH events in ~10yrs
Circular Electron Positron Collider (CEPC)
Ecm240GeV, luminosity ~21034 cm-2s-1, can also run at the Z-pole
Precision measurement of the Higgs boson (and the Z boson)
Phase 2: a discovery machine; pp collision with Ecm  50-100 TeV; ep, HI options
Super proton-proton Collider (SppC)
e+e-  ZH
e+
IP1
e-
LTB
e+ eLinac
BTC
BTC
(240m)
IP2
Ecm(GeV)
favored post BEPCII accelerator based particle physics
program in China
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CEPC Organization
•
Institution Board and Steering Committee formed in the kick-off
meeting in September 2013; conveners appointed for the three
working groups: Accelerator, Theory and Detector & Physics
Find out more: http://cepc.ihep.ac.cn/index.html
International workshops and regular group meetings to coordinate efforts
Schools and hand-on tutorials to train students – important to inspire more
young people to directly participate in the activities
–
•
•
 The CEPC management was reorganized in May 2015, after the preCDR,
July 15, 2016
to move forward with the CDR process;
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CEPC and SppC
Physics
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CEPC-SppC Accelerators
• e+e- collider
first phase
Higgs produced above the e+e-  ZH threshold
Collide e+e- at Ecm~240GeV，σ~ 200 fb
Need 250 fb-1/year/IP —> 1M Higgs particles in 10 years
Goal
• pp collider
after upgrade
Ecm ~70 TeV or higher
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CEPC design goal
• Limit SR power to 50 MW per beam
• CEPC: single ring, head-on collision, up to 250 GeV
• FCC-ee: double ring, large crossing angle, up to 350 GeV
CEPC:
106 Higgs
1010 Z
FCC-ee:
107 Higgs
1012-13 Z
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Science at CEPC and SppC
• Electron-positron collider (90, 250 GeV)
– Higgs Factory: Precision study of Higgs(mH, JPC, couplings)
• Similar & complementary to ILC
• Looking for hints of new physics
– Z & W factory: precision test of SM
• Deviation from SM ? Rare decays ?
– Flavor factory: b, c, t and QCD studies
• Proton-proton collider( 70 - 100 TeV)
– Directly search for new physics beyond SM
– Precision test of SM
• e.g., h3 & h4 couplings
Precision measurement + searches:
Complementary with each other
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CEPC

Precise measurements of the Higgs properties
as a Higgs Factory (similar to ILC@250 GeV)
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
Mass, JPC, couplings, etc. → reach (sub-) percentage accuracy
Precise measurements of Electroweak Symmetry-Breaking parameters
at Z-pole and WW threshold

m Z , mW , Z , sin 2Weff ,  S , etc. + searches for rare decays
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CEPC
Precision Higgs Physics by CEPC
% precision  M ~ 1 TeV
CEPC/FCC-ee to new physics  ~  10 over LHC
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CEPC preCDR Volume 1 (p.9)
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CEPC
Search for Deviations from SM
CEPC preCDR Volume 1 (p.10)
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CEPC and SppC
Accelerators progress and status
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CEPC Accelerator
(preCDR)
CEPC Accelerator Baseline Design
Single ring: cheap, low lumi.
6~10 GeV
Energy Ramp
10 ->120GeV
Electron
Linac
Double ring: expensive, high lumi
Local Double ring: a balance?
Booster
Positron
injection
CEPC Accelerator local double rings
Collision
ring
Pretzel scheme to separate
opposing beams at crossings
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CEPC main parameters
Parameter
Design Goal
Parameter
Particles
Beam energy [E]
Number
of IP[N
Center
ofIP] mass
Unit
Value
GeV
120
e+, eCircumference [C]
2
SR loss/turn
0]
240[UGeV
50 (48)
Bunch population [Ne]
energy
Bunch number/beam[nB]
Parameter
-1
Integrated
luminosity
(per
IP
per
year)
250
fb
SR power/beam [P]
MW
51.7
Beam current [I]
Unit
Value
m
54752
GeV
3.11
3.79E+11
mA
16.6
Bending
[ r]
No.radius
of IPs
m
6094
momentum
2 compaction factor [p]
Revolution period [T0]
s
1.83E-04
Revolution frequency [f0]
Hz
5475.46
emittance (x/y)
nm
6.12/0.018
b IP(x/y)
mm
800/1.2 (3)
Transverse size (x/y)
mm
69.97/0.15
xx,y/IP
Bunch length SR [ss.SR]
mm
2.14
Bunch length total [ss.tot]
mm
2.65
Lifetime due to Beamstrahlung
min
47
lifetime due to radiative Bhabha
scattering [tL]
min
51
GV
6.87
RF frequency [frf]
MHz
650
118800
Synchrotron
p, poscillation tune [ns]
0.18
5.99
Damping partition number [Je]
2
Parameter
RF voltage [Vrf]
Harmonic
number [h]
Particles
Energy acceptance RF [h]
%
Center of mass energy
Energy spread SR [s ]
%
d.SR
Energy
spread total luminosity
[sd.tot]
%(per
Integrated
0.132
0.118/0.083
Design Goal
70 TeV
Energy spread BS [s
0.163year) ng
IP per
3.36E-05
d.BS]
%
(TBD)
0.096
0.23
Transverse damping time [nx]
turns
78
Longitudinal damping time [ne]
turns
39
Hourglass factor
Fh
0.68
Luminosity /IP[L]
cm-2s-1
2.04E+34
No. of IPs
2
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J Gao et. al.
CEPC Accelerator
Preliminary
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CEPC accelerator layout
J Gao et. al.
Preliminary
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SppC Accelerator Design considerations
cross section of CEPC tunnel
•
Proton-proton collider luminosity
L0 
•
N p2 N b f repg
4e n b IP
F
 s
(F  1   c z
 2s
 x , IP
2

 )

x=
N p rp
4pe n
£ 0.004
Main constraint: high-field superconducting dipole magnets
–
50 km:
Bmax = 12 T, E = 50 TeV
–
50 km:
Bmax = 20 T, E = 70 TeV
–
70 km:
Bmax = 20 T, E = 90 TeV
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Bmin 
2 ( B r )
C0
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SppC accelerator general design
Parameter
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•
Value
Circumference
54.36 km
Beam energy
35.3 TeV
Dipole field
20 T
Injection energy
2.1 TeV
Number of IPs
2 (4)
Peak luminosity per IP 1.2E+35 cm-2s-1
Beta function at collision
0.75 m
Circulating beam current
1.0 A
Max beam-beam tune
0.006
shift per IP
Bunch separation
25 ns
Bunch population
2.0E+11
SR heat load @arc
56.9 W/m
dipole (per aperture)
8 arcs (5.9 km) and long
straight sections
(850m*4+1038.4m*4)
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SppC challenges
• High field magnets: both dipoles (20 T) and quadrupoles
(pole tip field: 14-20 T).
• Beam screen and vacuum: very high synchrotron
radiation power inside the cold vacuum:
• Collimation system: high efficiency collimators in cold
sections: new method and structure ?
• ……
A R&D plan is developed.
Main focus is the magnet
seeking collaboration with industry, HT
conductor research units, international
partners
A Conceptual design of 20-T Nb3Sn + July
HTS15,common
coil dipole magnet from IHEP
2016
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Can be downloaded from
http://cepc.ihep.ac.cn/preCDR/volume.html
403 pages, 480 authors
328 pages, 300 authors
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Volume III: Civil Engineering (in Chinese)
International Review of pre-CDR
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CEPC and SppC
The detector at the CEPC
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CEPC Detector (preCDR)
ILD-like detector with additional
considerations (incomplete list):
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Shorter L* (1.5/2.5m) → constraints
on space for the Si/TPC tracker
No power-pulsing → lower granularity
of vertex detector and calorimeter
Limited CM (up to 250 GeV) →
calorimeters of reduced size
Lower radiation background → vertex
detector closer to IP
…
Similar performance requirements to ILC detectors
–
–
–
5
-1
Momentum: s1/ p  5 10 GeV
← recoiled Higgs mass
3
2
Impact parameter: s r  5  10 /( p  sin  ) mm
← flavor tagging, BR
sE
 3  4%
Jet energy:
← W/Z di-jet mass separation
E
Sub-detector groups consider design options, identify challenges, plan R&D
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Ouyang Qun, HB Zhu et. al.
CEPC Detector – Pixel Vertex Detector
S
CMOS Sensor design and production
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Funding from Key Lab, IHEP
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Ouyang Qun, HB Zhu et. al.
CEPC Detector – Pixel Vertex Detector
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CEPC Detector – TPC
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CEPC Detector – TPC
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CEPC Detector – Calorimeters
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T. Hu et. al.
Funding：IHEP IF
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CEPC Detector – Detctor Magnet
L. Zhao et. al.
Funding：IHEP IF
Key technology:
• Optimization of Magnetic filed
• Superconductor
• Inner winding and impregnating
• Coil cryogenic system
• Power lines with HTS
• Manufacturing and assembling of huge scale yoke
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G. Li, MQ Ruan, YQ Fang et. al.
CEPC Detector – Software & Tools
Funding：IHEP IF
Analysis Tools
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G. Li, MQ Ruan, YQ Fang et. al.
CEPC Detector – Software & Tools
shrink the ILD detector
an important
step towards
sizing, design &
optimization of
the CEPC detector
Plus:
• full simulation of all analyses
• two papers: one published and other answering the referee’s questions
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CEPC and SppC
Site and civil engineering
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A candidate site for CEPC
Qinhuangdao
Beidaihe
Beijing
Tianjing
• 300 km from Beijing
• 3 h by car
• 1 h by train
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Civil construction consideration
• A credible design with cost estimate
• The key to keep the cost low
– Find a site geologically the best(granite)
– Optimize of the design
– Choose the right designer & construction
contractor
– Management
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CEPC and SppC
Other activities
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Other activities
• International workshops
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ICFA Higgs factory workshop, Oct. 2014
Workshop on CEPC organized by IAS HKUST, Jan. 2015
ICFA workshop on SC Magnet, June 2015
IHEP-DOE CEPC physics workshop in Aug. 10-12, 2015
Beijing-Chicago workshop on CEPC in Sep. 2015
IAS Conference Accelerator Program(Jan. 18-21, 2016)
More in 2016
• Training & professional development
• Communication, education & Outreach
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Training and Professional development
First Weihai Summer School (July-August, 2015)
CAS Center for Excellence in Particle Physics & Ministry
of Education Innvation Center for Particle Physics and
Interactions co-hosted WHSS at Shangdong University
TeV Physics Series in Huairou (July 26–August 9, 2015)
4 parts focus on LHC run2, CEPC CDR discussion on 8/9
CEPC Analysis Week (August 17-28, 2015)
30 young physicists from 10 universities and institutes
participated in the CEPC analysis (2) weeks, organized
by IHEP staff Manqi RUAN and Gang LI in August 2015
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CEPC and SppC
International collaboration
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International Collaboration
• Why we need international collaboration ?
– Not only because we need technical help
– But also for financial & political support in China
•
•
A way to integrate China better to the international community
A way to modernize China’s research system(“open door” policy)
• A machine for the community
• Right now the pre-CDR is mainly Chinese efforts with
international help
– An excise for us
– Build confidence for the Chinese HEP community
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International Collaboration
• 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 is formed to discuss
in particular this issue, together with others
– Working groups
– Workshops
– Preliminary organizations
next year
–…
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R&D Funding
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R&D Funding
• IHEP seed money
12 M RMB/3 years (2015-2017)
• Chinese Ministry of Sci. & Technology
~ 90 M / 6 years (2016-2021)
1st grant of ~36M RMB approved
• China National Commission on Dev. & Reform
No funding in 13th 5-year plan
we are seeking funding from other sources
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Summary
• CEPC is the first Chinese effort for a science
project at such a large scale; challenges are
everywhere
• Tremendous progresses up to now, but we
have a long way to go
• It is difficult but very exciting
• Let’s work together to make it happen
We fully support a global effort, even if the next
big circular collider is not built in China
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CEPC-SPPC Timeline (preliminary/ideal)
2nd Milestone: 13th 5yr-plan R&D (12M IHEP, ~100M MOST)
Pre-studies
(2013-2015)
R&D
Engineering Design
(2016-2020)
Construction
(2021-2027)
2035
2030
2025
2020
2015
CEPC
Data taking
(2028-2035)
1st Milestone: Pre-CDR (Spring of 2015) → R&D funding request to Chinese government in 2016
(China’s 13th Five-Year Plan 2016-2020)
R&D
(2014-2030)
2040
2030
2020
SPPC
Engineering Design
(2030-2035)
Construction
(2035-2042)
Data taking
(2042-2055)
This is a good schedule to follow
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CEPC-SppC
Physics wise，
CEPC+SPPC is ideal
Some considerations
•
•
•
•
•
•
Timing (after BEPCII)
Technological feasibility (experience at BEPC/BEPCII)
Economy  new funding to the community
Large & young population  new blood to the community
Affordable tunnel & infrastructure  still cheap in China now
Money will be taken by somebody anyway  It is a pity if we
miss it
• Too expensive ?
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–
–
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–
–
BEPC cost/4 y/GDP of China in 1984  0.0001
SSC cost/10y/GDP of US in 1992  0.0001
LEP cost/8y/GDP of EU in 1984  0.0002
LHC cost/10y/GDP of EU in 2004  0.0003
ILC cost/8y/GDP of Japan in 2018  0.0002
CEPC cost/6y/GDP of China in 2020  0.0001
SPPC cost/10y/GDP of China in 2036  0.0001- 0.0002
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Surface & underground
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Tunnel
• Concrete/Steel is not needed in granite
for the stability of the structure
• Water leaks are mainly cured by
Concrete + water proof material
• Concrete/Steel could bear more than half
of the tunnel cost
• Solution: steel plate  ~ 50% cost saving
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CEPC Detector – Calorimeters
July 15, 2016
T. Hu et. al.
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Current Status
• Initiated a global effort for the Conceptual Design
• pre-CDR completed
– No show-stoppers
– Technical challenges identified  R&D issues
– Preliminary cost estimate
• R&D issues identified and funding request underway
– Seed money from IHEP available: 12 M RMB/3 years
– MOST: ~ 100 M / 5yr, hopefully next year
– NCDR: ~1 B RMB / 5 yr, maybe 2017
• Working towards CEPC CD by 2016
– A working machine on paper
• Site selection
• Internationalization & organization
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