Particle Physics Research in China Hesheng Chen Institute of High Energy Physics Beijing 100049, China Outline 1. Introduction 2. BEPC/BEPCII 3. Daya Bay reactor neutrino experiment 4. Particle astrophysics experiments a) Yanbajing cosmic ray observatory b) Space experiments 5. Future plan 6. Closing remarks 2 Frontiers of Particle Intl. Cooperation: – LHCexp. Physics in China – ILC/CLIC? – … • BEPCII • Daya Bay ν • Daya Bay ν II • Cosmic rays • Space experiments • Deep underground Institute of High Energy Physics • Institute of Modern Physics: established at 1950 • Institute of High Energy Physics: independent Institute for Particle physics at 1973 → Comprehensive and largest fundamental research center in China – 1300 employees, 3/4 of them are physicists and engineers, – 550 PhD Students and 60 postdoctors • Goal of IHEP: multiple discipline research center based on large scientific facilities. 4 Major research fields at IHEP • Particle physics: – Charm physics @ BEPC – LHC exp. – Yangbajing cosmic ray observatory – particle astrophysics: HXMT, – Neutrino physics : Daya Bay reactor n exp. • Accelerator technology and applications – High Lumi. e+e- collider: BEPCII – High power proton accelerator: CSNS,ADS • Radiation technologies – Synchrotron radiation source and applications – Spallation neutron source and application • Construction and operation of large scientific facilities • Multiple discipline research: life science, nano-sciences, nuclear imaging, environment…… • 5 University Groups • Peking Univ. • Tsinghua Univ. • University of Sciences and Technology of China • Shandong Univ. • Huazhong Normal Univ. • Shanghai Jiaotong Univ. • Nanjing Univ. • …… 6 NSFC: one of major funding agencies for particle physics in China Supports particle physics research projects national wide, including • Research in experiments • Theory • International cooperation: LHC exp. …… • R&D of accelerator and detector • Innovation in the experimental facilities • …… 7 2. Beijing Electron Positron Collider (BEPC) BEPC: constructed 1984-1988 Ebeam~ 1–2.5 GeV BESI: run from 1989-1998 BESII: run from 1999-2004 BECPII upgraded 2004-2008 Ebeam~ 1–2.3 GeV BESIII: run from 2008 -charm energy region 8 With BESI and BESII data precision measurement of mass: a factor of 10 improved. Lepton universality! R measurements improve uncertainties by a factor of 2-3 2 (R/R6%). Large impact to MH.a(Mz ), g-2 New particles X(1835) observed. Hard to be interpreted as conventional hadrons. ppbar bound state? Precision measurements on the Charm physics require high statistics and small sys. errors → Major upgrade: BEPCII / BESIII (2004-2008) 9 9 BEPCII: a high luminosity double–ring collider SC RF Two rings 10 Interaction Region of BEPCII 11 8 800 ) -1 s Beam current (mA) -2 Peak [email protected]: 6.5x10 6 600 cm 32 • Luminosity enhanced: 4 coupling, and increasing beam current 400 2 200 对撞亮度 正电子流强 负电子流强 Luminosity (×10 0 0 日 日 日 日 日 日 日 日 日 日 日 日 日 1 3 9 8 23 月 15 10 21 月 月 14 17 23 n 24 12 月 月 2 月 月 月 5 月 月 月 月 月 4 1 2 3 3 12 x -- 1 12 12 12 12 > 0.5 (0.506), reducing 32 8XCESR emittance C 2010 2011 BESIII collaboration EUROPE (10) US (6) Germany: Univ. of Bochum, Univ. of Hawaii Univ. of Giessen, GSI，Mainz，HIM Univ. of Washington Russia: JINR, Dubna; BINP, Novosibirsk Carnegie Mellon Univ. Italy: Univ. of Torino，Frascati Lab Univ. of Minnesota Netherland：KVI/Univ. of Groningen Univ. of Rochester Korea (1) Univ. of Indiana Souel Nat. Univ. Japan (1) Pakistan (1) China(29) Tokyo Univ. Univ. of Punjab IHEP, CCAST, Shandong Univ., Univ. of Sci. and Tech. of China Zhejiang Univ., Huangshan Coll. Huazhong Normal Univ., Wuhan Univ. Zhengzhou Univ., Henan Normal Univ. Peking Univ., Tsinghua Univ. , Zhongshan Univ.,Nankai Univ. Shanxi Univ., Sichuan Univ Suzhou Uni., Hangzhou Normal Uni. Hunan Univ., Liaoning Univ. 48 institutions Henan Uni. of Sci. & Tech., ~ 300 collaborators Nanjing Univ., Nanjing Normal Univ. Guangxi Normal Univ., Guangxi Univ. Hong Univ., Hong Kong Chinese Univ. 13 BEPCII-BESIII-BSRF operation Accumulated the -1 J/ψ ψ' pb ψ(3770) largest directly ×106 1200 2900 1200 3000 produced J/y, y’ & y’’ 1000 2500 800 2000 samples in World： 600 600 1500 1.2 billion J/y 400 1000 （200 * MARK3 ） 200 500 0 0 0.6 billion y (20* CLEO ) 2.9 fb-1 y (3.5 * CLEO) Average daily lumi. at J/y increased by a factor of 120 compared with the one before upgrade. 5 – 6 months operation for HEP experiments, 3 months for dedicated SR mode @ 2.5GeV. During HEP run, parasitic SR mode works. 14 Important results from BESIII • Publish papers in world top ranking journals： – 29 papers published (PRL 10, PRD 16，PLB 1，CPC 2) – 5 papers submitted (PRL 2，PRD 3) – More than 40 analyses under internal refereeing • More than 80 talks at the international conferences, of them, about 35 are invited, plenary talks. BES is playing a leading role in charm physics in the world! BESIII：confirmed BESII results and observed more new resonances Confirmed pp enhancement, X(1870) determined its spin-parity 0-+ f1(1285) h(1405) J/ypp First observation of X(1870) J/ywp+p-h • X(2120),X(2370) Confirmed X(1835) (support pp X(1835) bound state explanation） • Observed two new states X(2120) and X(2370)！ + - J/yp p h’ BESIII: PRL106, 072002 (2011) BESIII: PRL107, 182001 (2011) BESIII: PRL108, 112003 (2012) J/y3p BESIII：PRL 108 (2012) 182001 0 First observed large isospin breaking : h(1405)f0(980)p h(1405) h(1405) f1/h f /h f (980)p-p+ 1 f (980)p0p0 3.7s 0 1.2s 0 observed narrow f0(980) – much narrow than PDG value + - 0 0 f0(980)p p f0(980)p p M = 989.9 ± 0.4 MeV M = 987.0 ± 1.4 MeV 17 G = 9.5 ± 1.1 MeV G = 4.6 ± 5.1 MeV Precision measurement of hC(1S)mass, width from yh (1S) C BESIII: PRL108, 222002 (2012) KsKp K+K-p0 p+p-h KsK3p 2K2pp0 6p The interference between hc and non-resonant hc is taken into account for the first time. The asymmetric hc lineshape is understanded, which is crucial in the precision measurement. 18 First observation of yhc(2S) Statistical significance >10 s BESIII: PRL109, 042003 (2012) New discovery! Great effort since BESI! + - + - 0 • Observed signal in KsK p +c.c.，found evidence in K K p -4 • First measured Br(y‘ hc(2S))=(6.8±1.1±4.5) ×10 -4 • [Theoretical expectation: (0.1-6.2)10 ] • Experimental challenge: detect photon of 50 MeV! 19 Lithography 6 wigglers and 14 VUV Middle energy beam lines. LIGA Macromolecular > 500 exp./year from > 100 institutions Soft X-ray Optics High-pressure diffraction X-ray Diffraction Small angle scattering BEPC Photoemission SpectroscPopy [email protected] 1w1 Topography 4w1 X-ray fluorescence XAFS analysis Diffuse Scattering Beijing Synchrotron Radiation Facility 20 Distribution of user’s subject Misc Material 9% Environment Science Two modes running for users: 17% 18% Solid Life Science Physics Chemistry 18% Dedicated mode, E = 2.5 GeV, 15% and Chemistry 15 beam lines on Engiineering 23% Regional distribution of user Parasitic mode, 6 beam lines on when running for HEP 3. Precision measurement of n mixing 13 Daya Bay reactor n experiment • Daya Bay nuclear power plant: 6 reactor cores, 17.4 GW • Mountains near by, easy to construct a lab with enough overburden to shield cosmic-ray backgrounds • Tunnel construction finished. Begin data taking with Near sites middle 2011, Near-Far configuration Dec. 2012 • First results（March 2012） 22 Daya Bay Experiment: Layout Redundancy !!! Relative measurement to cancel Corr. Syst. Err. 2 near sites（360m & 500m), 1 far site (1600m & 1900m) Multiple AD modules at each site to reduce Uncorr. Syst. Err. Far: 4 modules，near: 2 modules Cross check; Reduce errors by 1/N Multiple muon detectors to reduce veto eff. uncertainties Water Cherenkov： 2 layers RPC： 4 layers at the top + telescopes 2013/7/16 23 Daya Bay collaboration Europe (3) JINR, Dubna, Russia Kurchatov Institute, Russia Charles University, Czech Republic North America (14) BNL, Caltech, George Mason Univ., LBNL, Asia (15) Iowa state Univ. Illinois Inst. Tech., Princeton, IHEP, Beijing Normal Univ., Chengdu Univ. RPI, UC-Berkeley, UCLA, Univ. of Houston, of Sci. and Tech., CGNPG, CIAE, Dongguan Univ. of Wisconsin, Virginia Tech., Polytech. Univ., Nanjing Univ.,Nankai Univ., Univ. of Illinois-Urbana-Champaign, Shenzhen Univ., Tsinghua Univ., USTC, Zhongshan Univ., Hong Kong Univ. Chinese Hong Kong Univ., Taiwan Univ., Chiao Tung Univ., National United Univ. ~ 200 collaborators China: civil construction+½ detector, US:1/2detector(34M$) Full data taking since the end of 2012 2 Precision Measurement of Sin 213 Observation of electron anti-neutrino disappearance: R = 0.940 ±0.011 (stat) ±0.004 (syst) announced on Mar. 8, 2012 2 F.P. An et al., NIM. A 685(2012)78 Sin 213 = 0.092 0.016(stat) 0.005(syst) c2/NDF = 4.26/4, 5.2 σ for non-zero θ F.P. An et al., Phys. Rev. Lett. 108, 13 (2012) 171803 2013/7/16 27 Updated results R = 0.944 ±0.007 (stat) ±0.003 (syst) 2 Sin 213 = 0.089 0.010(stat) 0.005(syst) 2 c /NDF = 3.4/4, 7.7 σ for non-zero θ13 2013/7/16 28 LHC Experiments 1. CMS: IHEP, Peking Univ. – 1/3 of CSC at muon end caps (IHEP) – RPC of barrel muon (Beijing Univ.) – Remote operation center – Data analysis and Physics studies 2. Atlas: IHEP, USTC, Shandong U, Nanjing U. – Drift Monitor chambers (IHEP) – TGC (Shandong Univ.) – Data analysis and Physics studies 3. LCG: Tier 2 with 2000 cores 4. LHCb: Tsinghua Univ. 5. Alice: Huazhong Normal Univ.