COLLEGE STATION -- As their football squads prepare to meet for the first time in Southeastern Conference history Saturday (Oct. 20) at Kyle Field, Texas A&M University and Louisiana State University are teaming up to study collisions of another variety -- the nuclear kind -- on one of the world's biggest stages for nuclear astrophysics, Japan's RIKEN Nishina Center for Accelerator-Based Science. While Johnny "Football" Manziel undoubtedly will have many Saturday moments in the sun, Texas A&M and LSU physicists are looking to that same sun and its fellow stars as both the architects and inhabitants of our universe in an effort to better understand nuclear reactions and the resulting energy that makes life on Earth possible. "When you have a nuclear reaction, you have a tremendous amount of energy released," said Robert E. Tribble, distinguished professor of physics at Texas A&M and director of the Cyclotron Institute. "Solar energy is a product of a nuclear reaction. We're trying to find out exactly how the elements were formed and, in the process, how the energy that makes life on Earth possible was created." Tribble and LSU physics professor Jeffrey C. Blackmon are co-principal investigators in a United States Department of Energy-funded international collaboration that is exploring the outer limits of nuclear reactions along with colleagues at two additional U.S. universities (Texas A&M University-Commerce and Washington University in St. Louis) and in five other countries (IFIN-HH Bucharest, Romania; Universite de Caen, France; INFN, Sezione di Pisa, Italy; Oxford University, United Kingdom; Kyushu University, Japan). Tribble notes that a critical early part of the study is a series of experiments using rare isotope beams (RIBs) at the newly commissioned Radioactive Isotope Beam Factory (RIBF) at RIKEN, widely recognized as the most powerful radioactive beam facility in the world. Tribble says researchers there are doing cutting-edge experiments with nuclei that only live fractions of a second -- rare, infinitesimal windows in which to gain valuable insight into energy‘s essence and answers. "These experiments will provide important information about rates of nuclear reactions that occur in stellar explosions," Tribble added. "Some of the reactions that happen in stars happen in nuclei at the edge of stability within the shortest possible time span during which we can access them. Stars are just big balls of particles that are undergoing nuclear reactions. The reactions in our sun, which is a relatively small star, provide heat and light to us on Earth. It's important to understand these reactions in order to understand the very basis of life as we know it." The collaboration will focus on both proton- and neutron-breakup reactions at intermediate energies, with the goal of using the resulting data to better understand single-particle properties and to determine reaction rates in larger stellar explosions, such as supernovaes and X-ray bursts. By understanding how nuclear reactions work at a base level from both single-nucleon removal and recapture standpoints, Tribble says they can extend that knowledge to predict likely patterns of atomic behavior in more complex situations and at stellar energies for nuclei far from stability, whether in the cosmos or here on Earth. "We don't know what the chain of reactions is within stars, but we can figure out what the probability of certain reactions is," Tribble said. "For this study, we are focusing on p-gamma and n-gamma reaction rates, which are important in calculating how stars are born." Tribble's individual research group within the Cyclotron Institute is helping to develop the necessary equipment for the collaboration's experimental program -- specifically, a large silicon detector array that will incorporate both existing state-of-the-art technology and generate cost-effective extensions of that technology to enable silicon detector readout. Meanwhile, Blackmon's LSU group is working with the Texas A&M and Washington University groups to incorporate front-end electronics into a working portable data acquisition (DAQ) system that will allow user-friendly inspection and analysis and ultimately easy integration between laboratories. Blackmon's team will be in charge of maintaining this software and providing the integration and linkages between the current software and the proposed systems at both Texas A&M and RIKEN. "We also plan to implement the hardware so that it can be inspected via an Internet interface from anywhere in the world," Tribble said. "This requires a merger of two technologies already in use by Washington University. Such a system can have all eyes on a problem in short order and should probably be considered a requirement of the new century." With Japanese funding now secured for a very large new spectrometer, SAMURAI, to be built at RIKEN, Tribble says the time is right to begin developing a detector system that can be used in conjunction with SAMURAI to carry out a broad range of reaction and breakup studies at RIKEN energies -- a program that eclipses the initial suite of experiments proposed by the collaboration in its original letter of intent to RIKEN in January 2008. "The technology that we will develop will have broad application at many existing nuclear physics laboratories using stable or rare isotope beams, in addition to future RIB facilities," Tribble said. "And the training of students and postdoctoral research associates will be important contributions to the future workforce in this field." To learn more about the project, overall scope of work or partners involved in the $800,000 Department of Energy award, which runs through 2014, visit http://cyclotron.tamu.edu.
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