1997

Jul.

IHEP presented a proposal for a “BEPC Upgrade Program” to the Chinese Academy of Sciences (CAS), with the idea of a single-ring twist orbital.

1999

Jun.

CAS submitted the document “Strategy for the Development of High Energy Physics in China” to the 5th meeting of the Leading Group on National Science and Education, presenting near- and long-term targets for high energy physics in China, including the proposal for BEPCII. The National Science and Education Leading Group decided to increase the annual budget for BEPC, and to fund equipment upgrades and future R&D.

2000

Jul.27th

The National Science and Education Leading Group, at their 7th meeting, reviewed and agreed in principle with the CAS on their report “Targets for our National High Energy Physics and Advanced Accelerator Programme”, and agreed to upgrade the very successful BEPC accelerator.

2001

Apr.

Lu Yongxiang, the President of the CAS, wrote to Vice-Premier Li Lanqing that the CAS supported the idea of a double ring for BEPCII.

2002

Sep.4th

The China International Engineering Consulting Corporation evaluated the BEPCII project proposal.

2003

Oct.30th

The National Development and Reform Commission responded to the BEPCII feasibility study report.

2004

Nov.19th

BEPCII made step-by-step progress – the electron linear accelerator was installed and the electron beam successfully commissioned.

2005

Mar.19th

The positron beam was successfully commissioned in the BEPCII linear accelerator.

2006

Nov.18th

Electron beam was successfully accumulated in the storage ring.

2007

Nov.18th

Electrons and positrons successfully collided for the first time in BEPCII.

2008

Jan.29th

The storage ring realized collisions at 500 mA×500 mA, with luminosity over 1×10³²cm^-2s^-1, ten times the luminosity before the upgrade.

2009

Jul.17th

BEPCII passed the National Acceptance Test, which means that IHEP had successfully accomplished construction BEPCII on time, on budget, and to a high quality.

2010

Jan.13th

The Ministry of Science and Technology announced that BEPCII passing the National Acceptance Test was ranked top of the list of China’s Top Ten Basic Research news items of 2009.

2011

Apr.8th

BEPCII luminosity exceeded 6×10³²cm^-2s^-1, up to 6.492×10³²cm^-2s^-1.

2012

May.22nd

BEPCII/BESIII collected one billion J/Ψ events in one run, which is important for physics results in the J/Ψ energy area. In this run, BEPCII gathered 1.03 billion events, a great improvement over the 58 million events collected in two years of running from 1999-2001.

2013

March.8th

BEPCII luminosity exceeded 7×10³²cm^-2s^-1, up to 7.08×10³²cm^-2s^-1, at the design energy of 1.89 GeV.

Jul.17th

President Xi Jinping visited BEPCII at IHEP, greatly inspiring the scientists and engineers working on the collider.

2014

Nov.18th

The luminosity of BEPCII reached 7.15×10³²cm^-2s^-1, at the design energy of 1.89 GeV, with 620 mA double-beam collisions. On Nov. 19, the luminosity broke through 8.0×10³²cm^-2s^-1, reaching 8.04×10³²cm^-2s^-1, followed by 8.53×10³²cm^-2s^-1on Nov. 20.

2015

Jul.14th

Beijing Synchrotron Radiation Facility (BSRF) successfully ran in top-up mode, with the beam current controlled at 250 mA±0.1 mA, reaching an internationally advanced level. This was an important milestone in BSRF improving its performance.

2016

Apr.5th

The luminosity reached 1×10³³cm^-2s^-1, achieving the design goal of BEPCII. This means the performance is 100 times better than the old collider. This luminosity is a new world record in this energy range.