Snow Mass RF Townhall Meeting Spectroscopy Hadron Physics

Snow. Mass RF Townhall Meeting : Spectroscopy Hadron Physics Potential of a Super Tau-Charm Facility (STCF) Haiping Peng penghp@ustc. edu. cn University of Science and Technology China (USTC) State Key Laboratory of Particle Detection and Electronics 1

SM & QCD p The asymptotic freedom of QCD in high energy region is precisely test p But need more experimental inputs in the low energy region, color confinement p Lepton and charmed quark provide excellent platform to study the QCD 2

QM & Spectroscopy Quark Model (QM) successfully describes the structure of sub-atom Conventional hadrons Exotic Hadrons meson baryon In last two decades, a series of new states (Tetraquark, Pentaquarks) are found, however, their internal compositions are not identified yet : p Main reason : imperfect on the perturbative QCD p Incorporating theory with experimental observation, to improve power of prediction 3 Comprehensively establish the hadron spectrum and intensively

Broad Physics at c energy region 7 • • Hadron form factors Y(2175) resonance Mutltiquark states with s quark MLLA/LPHD and QCD sum rule predictions • • • Light hadron spectroscopy Gluonic and exotic states Process of LFV and CPV Rare and forbidden decays Physics with lepton • • • XYZ particles Physics with D mesons f. D and f. Ds D 0 -D 0 mixing Charm baryons Unique features ： p Transition region between QCD and p. QCD p Rich of resonance and exotics p Threshold characteristics, Quantum Correlation… 4

-c Physics at China 30 years history, leading role in tau-charm and hadrons physic area BEPCI /BESI-II （1031 cm-2 s-1 ） 1990 2000 BEPCII/BESIII (1033 cm-2 s-1 ) 2010 2020 (1035 cm-2 s-1 )? 2030 Challenge of BEPCII/BESIII： p Limited by length of storage ring, no large space and potential for the BEPCII/BESIII Will end her mission in 5 -10 years， STCF is a nature extension. upgrade. p Physics study limited by the Statistics (luminosity), CME …… 5

STCF at China p Central mass energy : 2 -7 Ge. V (BEPCII 2 -4. 7 Ge. V) p Peaking Luminosity : > 0. 5 1035 cm-2 s-1 at 4 Ge. V (two orders of BEPCII) p Potential to increase luminosity and realize beam Deliver at least 6 1 ab-1/year

Charmonium(-like) Spectroscopy Tasks : p Precisely measurement the transition p Search for the ? missing states p Understand the nature of unknown states p Search for the new exotic states p Very activity and large progress in past decades, a new territory for exotic hadron p Remarkable developments : the fail of hadron models to anticipate the rich charmonium spectrum 7

Charmonium(-Like) Production p STCF : XYZ-Meson factory Expected event number per year at STCF p Opportunities : • Precision Argand plot analysis • Precise mass and width measurements • Rare decays and new states searching 8

Searching for 1 -- Hybrid • 9

Competition with Belle-II @ 4. 26 Ge. V for + -J/ BESIII = 46%, Belle = 10% p B factory : Total integrate effective luminosity between 45 Ge. V is 0. 23 ab-1 for 50 ab-1 data p -C factory : scan in 4 -5 Ge. V, 10 Me. V/step, every point have 10 fb-1/year, 5 time of Belle II for 50 ab-1 data p -C factory have higher efficiency and low background than 10 B Factory

Light hadrons p Glueballs, hybrids, exotic states searching are greatly motivated in light hadrons scope, but challenged obviously. p Great progress on Lattie QCD, more experimental inputs are necessary p Charmonium decays is an ideal hunting ground • “Glue-rich”process • Clean and high statistics sample 11 • I (Jpc) filter in strong

STCF : factory 3 T J/ or 500 B /year p Systematic study of glueball, hybrid and conventional spectroscopy • Precision multi-variable analysis • Comprehensive measurement of all possible decay modes, e. g. J/ • … p Light hadrons / factory : important role in low energy QCD 1 T J/ p Baryon spectroscopy p Hyperon decays : CP asymmetry violation… 3 T J/ 12

Vector Mesons 13

r(2150) and (2170) r(2150) (2170) STCF : p Based on isospin and OZI rule, precisely measure resonances parameters, and decay strength, e. g. (2170) @ p Comprehensive study of decays ：e. g. e+ e- → KK , KK p Complicate intermediate states, large sample and PWA 14

Charmed hadrons Charmed hadron Spectroscopy provide an ideal role in studying the dynamics of the light quarks in the environment of a heavy quark, … 15

Activities and Progress Form the organization, build up working group (2018) Regular meeting, very active Toward to have CDR and TDR in 5 -7 years 16

Preliminary CDR Three volumes (Physics, Accelerator and Detector), will released (Physics/Detector) before the end of this year 17

International Collaboration SCT at Novosibirsk, Russia Budker Institute of Nuclear Physics Long history…. . l a n io t a n er t n i p Carry out joint efforts on R&D fore some key technology, v i s n n meeting monthly o e i p Joint workshop : China, nt Russia, t a i r o g b Europe n a i l k l e o C , • 2018 UCAS Se , Novosibirsk joint Orsay p • Others efforts： 2019 Moscow • • 2020 China) online FTOF(Guangzhou, for PID (LAL) • u. Rwell for inner tracking (Frascati ) 18

Summary p Physics at -c energy region is abundant, and is unique for the hadron spectroscopy and test QCD p A super -c facility (STCF) is nature extension of BEPCII/BESIII and a viable option for post. BEPCII era in China p Great progress has achieved for feasibility study of STCF p Strategy & Plan • Intend to have a CDR and TDR in five years • Construction site: Currently open 19

Tentative Schedule 20312018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 20412042 Form International Collaboration Conception Design Report (CDR) Technical Design Report (TDR) Construction Commissioning Upgrade 20

Funding Support USTC : Initial funds 15 M CNY (2018 -2020) CAS : Program for cultivation of international big science program 6 M CNY (2021 -2025) NSFC : Key technology R&D 3 Key programs + several general programs 10 M CNY Seeking for the funding support on R&D from MOST, CAS and local goverment 21

Budget Estimation R&D : 250 M CNY, Construction : 4 B CNY (Very Rough) 22

Candidate Site : Hefei One of three integrated national science centers, which will play important role in ‘Megascience’ of China in Hefei Integrated National Science Center near future p University of Science and Technology of China (USTC) p National Synchrotron Radiation Lab and Hefei Light Source, operated by USTC p The only National Lab operated by University in China. (Totally Four officially approved p Pay a lot of attention on accelerator National Labs in China) facilities p Hefei Advanced light source is under 23

Candidate Site : Canton Institute of Modern Physics, CAS, proposed building HIAFEic. C In Huizhou, Canton Proton/Ion Exploring feasibility and Electron strategy Eic. C p Complementarity in physics p Sharing e-ring and infrastructure p Joint R&D and Key technologies Eic. C IP-1 Eic. C IP-2 ERL-cooling Positron STCF HFRS SRing Positron Damping Ring Eic. C Ion-Ring STCF IP Eic. C E-Ring STCF E-Ring BRing HIAF STCF Positron-Ring i. Linac Electron/Positron Accelerator E-Injector A Hadron Physics Internal SECR 24

Accelerator based project in China Consensus in HEP community in China (about accelerator based particle physics project) Web of Division of High energy physics, Chinese Physics Society http: //www. ihep. cas. cn/xh/gnwlxh/zxdt/ CEPC and HIEPA (STCF) are the viable options … Carry out the work in both high energy frontier and intensive luminosity frontier Unanimity to consent to support R&D of STCF, …it is necessary to carry out the R&D 25