Beijing Spectrometer

Beijing Spectrometer Detector (image by the BESIII Collaboration)

An international team of scientist, which operates the Beijing Spectrometer (BESIII) Experiment at the Beijing Electron Positron Collider in China, recently began a series of studies aimed at understanding the anomalous Y(4260) particle. As a striking and unexpected first observation from these new studies, the collaboration has reported that the Y(4260) particle in fact decays to a new—and perhaps even more mysterious—particle that they named the Zc(3900).

The University of Hawaiʻi at Mānoa’s High Energy Physics Group in the physics and astronomy department is part of the international collaboration that made this discovery. High energy physics involves the study of subatomic particles that are the building blocks of matter and the forces that act between them.

“The new observations challenge what was thought to be a well-understood system of possible configurations of charmed- and anti-charmed quarks, those that were considered to be among the simplest and most easily understood subatomic particles,” said Professor Frederick A. Harris, co-spokesperson for the experiment.

Recent discoveries of several new particles, including the Y(4260) and now the Zc(3900), suggest that more complex structures have to be considered.

A description of new particle was reported by the Chinese Academy of Sciences’ Institute of High Energy Physics and submitted to the Physical Review Letters. It is available at

For more information, read the UH Mānoa news release or the full text of the Chinese Academy of Sciences’ announcement.

Beijing Spectrometer collaboration

UH Mānoa joined the Beijing Spectrometer collaboration in 1993 and since then has had a strong impact on its research program.

In particular, UH Manoa has played a key role in developing a number of the critical instrumental components of the BESIII Experiment and its predecessor BESII. In 2010, UH Mānoa helped construct the beam energy measurement system for the Beijing electron-positron collider, improving the precision of BESIII’s particle measurements.

The BESIII Experiment research team is comprised of about 350 physicists from 50 institutions in 11 countries. U.S. groups include UH Mānoa, Carnegie Mellon University, Indiana University, the University of Minnesota and the University of Rochester.

Leave a Reply

Your email address will not be published. Required fields are marked *