学术报告:Transport Model Comparison Project

报告题目:Transport Model Comparison Project

报 告 人:Betty Tsang (Michigan State University)

报告时间:2015年11月4日(星期三)上午10:30-11:30

报告地点:嘉定学术活动中心307会议室

报告简介:

The importance of transport models to nuclear reactions is similar to the role of shell models to nuclear structure. However unlike nuclear structure the many-many body physics of nuclear reactions are much more complicated than shell models. While mean field theories like TDHF have been successful in describing low energy reactions (around Coulomb barriers) and cascade type of theories are successful in describing very high energy reactions, the regions between Fermi energy (~50 MeV/u) up to 400 MeV/u have presented numerous challenges to theorists as one has to take into account the effects of both mean field and nucleon-nucleon collisions which more often than not act against each other. Being creative in nature, there are often diverse ways to handle the mean fields and the NN collisions in different transport models leading to different and even at times contradictory interpretations of the same data. In January of 2014, the transport model communities met at Shanghai Jiao Tong University. As a result of work before, during and after the meeting, 9 BUU and 10 QMD codes were compared with heavy participations by the code authors. I will show the results of these comparisons in the hope that critical reviews of the results by the audience will lead to a better understanding of the differences of the codes and insights of the physics as the organizers are writing a paper on the results and a special volume book on the project.

Editors for “Simulations of heavy ion collisions using transport theories”, Springer

Lie Wen Chen, Shanghai Jaio Tung University, Shanghai, China

Betty Tsang, Michigan State University, East Lansing, USA

Hermann Wolter, University of Munich, Germany

Jun Xu, SINAP

Feng Shou Zhang, Beijing Normal University, Beijing, China

Ying Xun Zhang, China Institute of Atomic Energy, Beijing, China

报告人简介:

DEGREES AWARDED:

Bachelor of Science, California State University, Bakersfield 1973

M.S. Nuclear Chemistry, University of Washington, Seattle 1978

Ph.D Nuclear Chemistry, University of Washington, Seattle 1980

PROFESSIONAL ACTIVITIES:

Member, American Physical Society, American Chemical Society

Vice-Chair, Committee on the International Freedom of Scientists, 1994 (APS)

Chair, Committee on the International Freedom of Scientists, 1995 (APS)

Member, DNP program committee, 1995 – 1996

Member-at-large, Forum of International Physics, APS, 2005-2008

Vice-Chair, Nuclear Chemistry Gordon Research Conference, 2007

Chair, Nuclear Chemistry Gordon Research Conference, 2008

Member, APS Andrei Sakhorov Prize Selection Committee, 2007-2009.

AWARDS:

Heinz-Pagels Human Rights Award, New York Academy of Science, 2000

Citations: For extraordinary work in support of scientists under repression.

Fellow, American Physical Society, 2006

Citations: For her contibutions towards the understanding of reaction dynamics, the density dependence of the symmetry energy, and the extraction of spectroscopic factors”

APPOINTMENTS:

Professor, NSCL, Michigan State University May 1995 – present

Adjunct Professor, Physics Dept, Michigan State University Dec 1993 - present

Senior Physicist, NSCL, Michigan State University Sept 1993 - May 1995

Staff Physicist, NSCL, Michigan State University Sept 1988 - Sept 1993

Physicist, NSCL, Michigan State University May 1984 - Sept 1988

Research Associate, NSCL, Michigan State University Dec 1980 - May 1984

Core Faculty, Center for Advance Study of International Development, MSU May 2005 - present

Biography:

Betty Tsang is a professor at the National Superconducting Cyclotron Laboratory, an Adjunct Professor at the Department of Physics and Astronomy and a core faculty member of the Center for Advance Study of International Development at Michigan State University. She was born in Hong Kong and received her primary and secondary education there before moving to the U.S. She received her PhD in Nuclear Chemistry at the University of Washington, Seattle. After graduation in 1980, she went to Michigan State University as a postdoctoral fellow and has been working there ever since.

In her research Tsang has investigated the equation of state and liquid gas phase transition of nuclear matter, the production of rare isotopes, and single particle structure of the nucleus via transfer reactions. Since 1980, she has published nearly 270 articles in refereed journals including 54 PRL. She has about 13,000 citations in Google scholar. Her work has involved collaborations of scientists from China, Brazil, Canada, France, Germany, Italy, Japan, Russia, and Vietnam. She has organized numerous conferences with international participants including the upcoming NuSYM16 in Tsinghua University, Transport16 at BNU next June and Transport16 held in Shanghai Jiao Tung University, in January, 2014. She became an American Physical Society Fellow in 2006. In 2000, she received the Heinz Pagels award from the New York Academy of Sciences.

The understanding of the behavior of nuclear systems in a wide range of densities, temperatures and proton-neutron asymmetries, i.e. the investigation of the equation of state (EoS) of nuclear matter, is a main goal of nuclear research. It is also an important input to the study of astrophysical objects and processes like neutron stars or core collapse supernovae. The EoS can be studied in the laboratory only in heavy ion collisions (HIC), where depending on the incident energy of the collision and the size of the colliding system a wide range of conditions can be created. However, heavy ion collisions are very dynamic processes, in which the EoS is not observed directly, but has to be inferred from the reaction products. The method relies on non- equilibrium theories, which model the reaction and have as input the EoS and effective NN cross sections. For the energies under consideration here, i.e., from the Fermi energy regime to relativistic energies, transport theories are the essential tool to obtain information from heavy ion collisions 
In a recent international workshop on simulations of low- and intermediate-energy heavy-ion Collisions help at the Shanghai Jiao Tung University in January, 2014 (Transport 14), we compared the calculations of Au+Au collisions at beam energies of 100 and 400 MeV/u from 9 BUU-type codes and 9 QMD-type codes. Activities continued past the conference for more than a year. In this talk, we will discuss the results of the comparisons and what insight we learn from it as well as future project for Transport 16.