Yong-Zhong QianProfessor, School of Physics and Astronomy
Minneapolis, MN 55455
Minnesota Institute for Astrophysics (MIfA)
Research & Teaching
Publications & Awards
Ph.D., University of California, San Diego, 1993
B.S., University of Science and Technology of China, 1989
Editorial Committee for Annual Review of Nuclear and Particle Science, 2015-2024
Editorial Board for Science China - Physics, Mechanics and Astronomy, 2013-2022
Editorial Board for Physical Review C, 2018-2020
Annual Summer School on Computational Astrophysics and Related Workshop, Tsung-Dao Lee Institute, Shanghai, China, 2017-2019
Nucleosynthesis and Chemical Evolution, 5-week INT program, University of Washington, Seattle, 2014
The Origin of the Elements: A Modern Perspective, European Center for Theoretical Studies in Nuclear Physics and Related Areas workshop, Trento, Italy, 2011
National Advisory Committee for the Institute for Nuclear Theory (INT), University of Washington, Seattle, 2007-2009
Fellow, American Physical Society, 2008
The First Stars and Evolution of the Early Universe, 5-week INT program, University of Washington, Seattle, 2006
Google Scholar: https://scholar.google.com/citations?user=PzOAIxUAAAAJ
Our Solar System: What Triggered Its Formation?
About 4.6 billion years ago, some event disturbed a cloud of gas and dust, triggering the gravitational collapse that led to the formation of the solar system. One hypothesis is that a nearby supernova - a star exploding at the end of its life cycle - initiated this event. My collaborators and I have examined why earlier forensic evidence based on studies of extinct radioactive nuclei in meteorites have been inconclusive, and shown how recent results from modeling supernovae and their impact on star formation have opened up new directions in researching the formation of our solar system.
Click here for a news report on our work and here for our paper published in Nature Communications.
Flavor Oscillations of Astrophysical Neutrinos
Using neutrinos produced by nuclear reactions in the sun, by interaction of cosmic rays with earth's atmosphere, and by accelerators and nuclear reactors on earth, a number of experiments showed that neutrinos oscillate among different flavors and therefore have mass. Yet some key parameters characterizing neutrino oscillations are unknown. New experiments such as MINOS and NOvA, in which the University of Minnesota plays a prominent role, are being carried out to probe these unknown parameters. Interestingly, supernovae that signify the explosive death of massive stars are prodigious sources of neutrinos and provide another venue to study neutrino oscillations. In fact, the number density of neutrinos near the core of a supernova is so large that new phenomena of neutrino oscillations arise. In particular, the flavor evolution for neutrinos of different energies traveling in different directions may be coupled together to produce collective oscillations. This new phenomenon is extremely sensitive to the unknown neutrino oscillation parameters, thereby allowing possible extraction of these parameters from the detection of neutrinos from a future supernova.
Diverse Supernova Sources for Neutrinos and Elements
A lecture on Neutrinos & Supernova Nucleosynthesis: https://www.youtube.com/watch?v=o-Y0clHDSqU
A lecture on The r-Process: Status & Challenges: https://www.youtube.com/watch?v=Q-G3zECnApw
Chemical Evolution of Galaxies
A lecture on Hierarchical Structure Formation & Chemical Evolution of Galaxies: https://www.youtube.com/watch?v=yq9PDIrahJg
McKnight Presidential Fellow, University of Minnesota, 2004-2006
Department of Energy Outstanding Junior Investigator, 2000-2004