We present the first lattice result of the near threshold $ \Lambda_c\Lambda_c $ scattering with $ I(J^P) = 0(0^+) $ . The calculation is performed on two $ N_f = 2+1 $ Wilson-Clover ensembles with pion mass $ m_\pi \sim 303 $ MeV and lattice spacing $ a = 0.07746 $ fm. Lüscher's finite volume method is utilized to extract the scattering parameters from the finite-volume spectrum. The coupled channel $ \Xi_{cc}N $ is ignored in the scattering analysis based on the observation that the energy levels computed from the $ \Lambda_c\Lambda_c $ and $ \Xi_{cc}N $ operators do not mix. The $ \Sigma_c\Sigma_c $ channel is not included either since the energy range explored in this study is well below its threshold. Our results indicate that the interaction in the $ \Lambda_c\Lambda_c $ single channel is repulsive, and the scattering length is determined to be $ a_0 = -0.21(4)(8) $ fm, where the first error is statistical and the second is systematic.

China

Hanyang Xing

Yiqi Geng

Chuan Liu

Liuming Liu

Peng Sun

Jiajun Wu

Zhicheng Yan

Ruilin Zhu

Lattice QCD study of Λ $\textit{c}$ Λ $\textit{c}$ scattering * Supported by NSFC (12293060, 12293061, 12293063, 12175279, 12435002, 12322503, 12175239). L. Liu also acknowledges the Strategic Priority Research Program of the Chinese Academy of Sciences with (XDB34030301) and Guangdong Major Project of Basic and Applied Basic Research (2020B0301030008). We also acknowledge the Science and Education Integration Young Faculty Project of University of Chinese Academy of Sciences (YSBR-101)

We report a feasibility study for violation in   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   decays at a Super Tau Charm Facility (STCF). With an expected luminosity of 1 ab   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   collected by STCF per year at a center-of-mass energy of 4.26 GeV, the statistical sensitivity for CP violation is determined to be of order   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   by measuring the decay-rate difference between   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   and   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$  . The analysis is performed using a reliable fast simulation software package, which can describe the detector responses properly and vary the responses flexibly for further optimization. Moreover, the energy-dependent efficiencies for reconstructing   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   are presented. The expected CP sensitivity is proportional to   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   in the energy region from 4.0 to 5.0 GeV. The sensitivity of CP violation is of order   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   with 10 ab   $\tau^{-}\rightarrow K_{S}\pi^{-} \nu_{\tau}$   integrated luminosity, which is equivalent to ten years' data taking in this energy region at STCF.

Haoyu Sang

Xiaodong Shi

Xiaorong Zhou

Xianwei Kang

Jianbei Liu

Feasibility study of CP violation in decays at the Super Tau Charm Facility  

This exploratory study computes two-photon decay widths of pseudo-scalar (
					) and scalar (
					) charmonium using two ensembles of 
					 twisted mass lattice QCD gauge configurations. The simulation is performed using two lattice ensembles with lattice spacings 
					 fm with size 
					 and 
					 fm with size 
					. The decay widths for the two charmonia are obtained within the expected ballpark, but are however smaller than the experimental ones. Possible reasons for these discrepancies are discussed.
				

Ying Chen

Ming Gong

Ning Li

Yu-Bin Liu

Zhaofeng Liu

Jian-Ping Ma

Yu Meng

Chao Xiong

Ke-Long Zhang

Lattice study of two-photon decay widths for scalar and pseudo-scalar charmonium This work is supported in part by the National Science Foundation of China (NSFC) (11335001, 11275169, 11405178, 11935017, 11575196, 11875169, 11775229). It is also supported in part by the DFG and the NSFC (11261130311) through funds provided to the Sino-Germen CRC 110 symmetries and the Emergence of Structure in QCD. This work is also funded in part by National Basic Research Program of China (973 Program) (2015CB856700). M. Gong and Z. Liu are partially supported by the Youth Innovation Promotion Association of CAS (2013013). This work is also supported by the Scientific Research Program Funded by Shaanxi Provincial Education Department (19JK0391) andNatural Science Basic Research Plan in Shaanxi Province of China (2019JM-001)

The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics. The Higgs boson will be the subject of extensive studies of the ongoing LHC program. At the same time, lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC, with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs boson. The Circular Electron Positron Collider (CEPC) is one of such proposed Higgs factories. The CEPC is an e+e− circular collider proposed by and to be hosted in China. Located in a tunnel of approximately 100 km in circumference, it will operate at a center-of-mass energy of 240 GeV as the Higgs factory. In this paper, we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements.
				

United States

Fenfen An

Yu Bai

Chunhui Chen

Xin Chen

Zhenxing Chen

Joao Guimaraes da Costa

Zhenwei Cui

Yaquan Fang

Chengdong Fu

Jun Gao

United Kingdom

Yanyan Gao

Yuanning Gao

Japan

Shaofeng Ge

Germany

Jiayin Gu

Fangyi Guo

Jun Guo

Tao Han

Shuang Han

Hongjian He

Xianke He

Taiwan

Xiaogang He

Jifeng Hu

Shih-Chieh Hsu

Shan Jin

Maoqiang Jing

Susmita Jyotishmati

Kiuchi Ryuta

Chia-Ming Kuo

Peizhu Lai

Boyang Li

Congqiao Li

Gang Li

Haifeng Li

Liang Li

Shu Li

Tong Li

Qiang Li

Hao Liang

Zhijun Liang

Libo Liao

Bo Liu

Hong Kong

Tao Liu

Zhen Liu

Xinchou Lou

Lianliang Ma

South Africa

Bruce Mellado

Xin Mo

Serbia

Mila Pandurovic

Jianming Qian

South Korea

Zhuoni Qian

Nikolaos Rompotis

Manqi Ruan

Alex Schuy

Lianyou Shan

Jingyuan Shi

Xin Shi

Shufang Su

Dayong Wang

Jin Wang

Liantao Wang

Yifang Wang

Yuqian Wei

Yue Xu

Haijun Yang

Ying Yang

Weiming Yao

Dan Yu

Kaili Zhang

Zhaoru Zhang

Mingrui Zhao

Xianghu Zhao

Ning Zhou

Precision Higgs physics at the CEPC Supported by the National Key Program for S&T Researh and Development (2016YFA0400400); CAS Center for Excellence in Particle Physics; Yifang Wang’s Science Studio of the Ten Thousand Talents Project; the CAS/SAFEA International Partnership Program for Creative Research Teams (H751S018S5); IHEP Innovation Grant (Y4545170Y2); Key Research Program of Frontier Sciences, CAS (XQYZDY-SSW-SLH002); Chinese Academy of Science Special Grant for Large Scientific Project (113111KYSB20170005); the National Natural Science Foundation of China(11675202); the Hundred Talent Programs of Chinese Academy of Science (Y3515540U1); the National 1000 Talents Program of China; Fermi Research Alliance, LLC (DE-AC02-07CH11359); the NSF(PHY1620074) ; by the Maryland Center for Fundamental Physics (MCFP); Tsinghua University Initiative Scientiﬁc Research Program; and the Beijing Municipal Science and Technology Commission project(Z181100004218003)

Using the one-boson-exchange model, we investigate the , , , , , and interactions by considering the one-eta-exchange and/or one-pion-exchange contributions. We further predict the existence of hidden-charm molecular pentaquarks. Promising candidates for hidden-charm molecular pentaquarks include a state with and the states with and . Experimental searches for these predicted hidden-charm molecular pentaquarks are an interesting future research topic for experiments like LHCb.

Rui Chen

Jun He

Xiang Liu

Possible strange hidden-charm pentaquarks from and interactionsSupported by National Natural Science Foundation of China (11222547, 11175073, 11675228), Major State Basic Research Development Program in China (2014CB845405) and Fundamental Research Funds for the Central Universities. Xiang Liu is also supported by the National Program for Support of Top-notch Young Professionals

The prompt and non-prompt production cross-sections for ψ (2S) mesons are measured using 2.1 fb −1 of pp collision data at a centre-of-mass energy of 7 TeV recorded by the ATLAS experiment at the LHC. The measurement exploits the ψ (2S) → J/ψ (→ μ + μ − ) π + π − decay mode, and probes ψ (2S) mesons with transverse momenta in the range 10 ≤ p T &lt; 100 GeV and rapidity | y | &lt; 2 . 0. The results are compared to other measurements of ψ (2S) production at the LHC and to various theoretical models for prompt and non-prompt quarkonium production.

France

Georges Aad

Brad Abbott

Jalal Abdallah

Samah Abdel Khalek

Azerbaijan

Ovsat Abdinov

Netherlands

Rosemarie Aben

Babak Abi

Maris Abolins

Canada

Ossama AbouZeid

Israel

Halina Abramowicz

Henso Abreu

CERN

Ricardo Abreu

Sweden

Yiming Abulaiti

Bobby Samir Acharya

Poland

Leszek Adamczyk

David Adams

Jahred Adelman

Stefanie Adomeit

Tim Adye

Montenegro

Tatjana Agatonovic-Jovin

Spain

Juan Antonio Aguilar-Saavedra

Switzerland

Marco Agustoni

Steven Ahlen

Faig Ahmadov

Italy

Giulio Aielli

Henrik Akerstedt

Torsten Paul Ake Åkesson

Ginga Akimoto

Russia

Andrei Akimov

Gian Luigi Alberghi

Justin Albert

Solveig Albrand

Argentina

Maria Josefina Alconada Verzini

Martin Aleksa

Igor Aleksandrov

Romania

Calin Alexa

Gideon Alexander

Gauthier Alexandre

Greece

Theodoros Alexopoulos

Muhammad Alhroob

Gianluca Alimonti

Lion Alio

John Alison

Benedict Allbrooke

Lee John Allison

Phillip Allport

John Almond

Alberto Aloisio

Denmark

Alejandro Alonso

Francisco Alonso

Cristiano Alpigiani

Andrew David Altheimer

Barbara Alvarez Gonzalez

Mariagrazia Alviggi

Katsuya Amako

Brazil

Yara Amaral Coutinho

Christoph Amelung

Dante Amidei

Portugal

Susana Patricia Amor Dos Santos

Antonio Amorim

Simone Amoroso

Nir Amram

Glenn Amundsen

Christos Anastopoulos

Measurement of the production cross-section of ψ (2S) → J/ψ (→ μ + μ − ) π + π − in pp collisions at s $$ \sqrt{s} $$ = 7 TeV at ATLAS