Institute of High Energy Physics, CAS, China
Professor Hesheng Chen is a particle physicist and Academician of Chinese Academy of Sciences. He received his Ph.D. in Physics from the Massachusetts Institute of Technology. He is currently the Head of Command and Engineering Manager of China Spallation Neutron Source (CSNS). He was the Director of the Institute of High Energy Physics, President of the High Energy Physics Association of China, and Vice President of the Chinese Physical Society.
Professor Chen is the co-director of a joint laboratory co-established by City University of Hong Kong (CityU) and the Institute of High Energy Physics under the Chinese Academy of Sciences (CAS). The joint laboratory on Neutron Scattering was launched on 27 February 2019, it is the only laboratory in Hong Kong for research into this discipline.
Professor Chen had made major contributions to the discovery of gluon jet and the systematic study of gluon physics in the Mark-J experiment at DESY. He also made important contribution to the precision measurement of the electro-weak parameters and demonstrating the validity of the Standard Model.
He made very important contributions to the design and construction of the hadron calorimeter, and the physics analysis in the L3 experiment at CERN. His work was the key part in determining of the number of neutrino generations and the precision measurement of the electroweak parameters in L3.
He made major contributions to the study of the strategy of the particle physics and high energy accelerator in China. He led the team of the Beijing Electron-Positron Collider (BEPC) and obtained important physics results in the charm energy region, including the precision measurement of R value between 2 to 5 GeV and the discovery of new resonance X1835, which could be a ppbar bound state. He proposed the BEPC upgrade project (BEPCII), which is a double ring collider in the existing tunnel with the luminosity improving by two orders of magnitude for the study of Charm physics. He is the BEPCII projector manager. Under his leadership, the project was finished on schedule and within the budget. The daily integrated luminosity of BEPCII has been increased by factors of more than 100 respectively. The new resonance of Zc (3900), which could be explained as a 4 quark state was discovered recently. The Daya Bay reactor neutrino experiment was designed and constructed under his leadership. The most precision measurement on the neutrino mixing parameter ⊖13 from the experiment determined the future direction of the neutrino physics experiment.
The China Spallation Neutron Source (CSNS) is a multidisciplinary research platform with neutron scattering. The site of CSNS is Dongguan, Guangdong Province. The facility comprises an 80-MeV H- Linac, a 1.6 GeV proton rapid cycling synchrotron (RCS), a tungsten target station, and two experimental halls for 20 neutron instruments. The RCS provides a beam power of 100 kW on the target in phase I. There are three initial instruments in the experimental halls. The construction of CSNS was finished on schedule and reached the specifications. The first neuron beam of CSNS was obtained in August 2017. The construction of CSNS went through the acceptance review organized by the Chinese Academy of Sciences in March 2018, and opened to users. CSNS runs stable with high efficiency. The proton beam power on the target reached the design value of 100kW in February 2020, and increased to 140kW Sept. 2022.
Currently, four neutron instruments are running and open to users. Four more user instruments are under commissioning. Another two will be ready next year. There are 4000 registered users in CSNS, and more than 900 experiments were carried out. Many interesting scientific results were obtained. The phase II of CSNS was approved by Chinese funding agency, including increasing the proton beam power of the accelerators and the target station to 500kW, and the construction of 9 neutron instruments as well as the muon beam and a proton test beam.
The construction, scientific results, and upgrade plan of CSNS will be reported.