Detector Array and Chamber for Study of Nuclear Reactions with Low-Energy Short Lived Beams

该项目将资助升级现有的由美国国家科学基金会资助的密歇根大学(UM)-圣母大学（UND）低能核研究设备“TwinSol”，该设备位于密歇根大学的核粒子加速器上。具体而言，该项目将包括建设一个新的散射室和一个相关的大面积核粒子探测器阵列，以及提高粒子的飞行时间能力，更好的真空等。这一升级将允许新一代的核物理实验，涉及研究低能短寿命（即放射性）核束的核反应。具体的实验将着重研究接近核稳定极限的非常富中子和质子的核的结构和反应机理。这样的原子核通常寿命很短（例如1秒或更短），新的、升级的仪器将允许以比以前更高的精度对许多这样的原子核进行详细的研究。尽管如此，这种短寿命的原子核（例如氦的短寿命同位素，有4个中子和2个质子，而氦的正常稳定同位素，有2个中子和2个质子）对正常恒星、超新星（爆炸的恒星）和其他极端天体物理环境中原子元素的合成是重要的。这包括许多原子元素的合成，这些元素对行星的形成和生命本身都很重要（氧、硅、钙、铁……）。该项目将对研究生、本科生和高中教育产生广泛的影响，以及培养一支具有技术素养的劳动力队伍，因为它将涉及密歇根大学和圣母大学的研究生和本科生，以及来自中西部地区其他几所学院和大学（主要是本科生）的教职员工和学生，靠近UM和UND。因此，这些学生在使用先进的、最先进的核加速器和核粒子探测器以及相关的超导加速器磁体方面的“实践”培训将提供重要的培训，并在许多可能的职业道路上应用（例如，涉及核技术，包括核医学或教学）。它还将使这些学校的教师参与到前沿的物理研究中，然后将这些研究纳入他们的课程作业、公共宣传职能等。

This project will fund an upgrade to the existing NSF-funded University of Michigan (UM)- University of Notre Dame (UND) low-energy nuclear research apparatus "TwinSol" located at the UND nuclear particle accelerator. Specifically, the project will include the construction of a new scattering chamber and an associated large-area nuclear-particle detector array, together with improved particle time-of-flight capability, better vacuum, etc. This upgrade will permit a new generation of nuclear physics experiments involving the study of nuclear reactions with short-lived (i.e. radioactive ) nuclear beams at low energies. Specific experiments will emphasize the investigation of the structure and reaction mechanisms of very neutron- and proton-rich nuclei near the limits of nuclear stability. Such nuclei generally are very short-lived (e.g. 1 sec or less) and the new, upgraded apparatus will permit detailed studies of many of these nuclei with better accuracy than previously possible. Such short-lived nuclei (for example the short-lived isotope of helium, 6He which has 4 neutrons and 2 protons in contrast to the normal, stable isotope of helium, 4He which has 2 neutrons and 2 protons) nonetheless are important for the synthesis of atomic elements in normal stars, as well as in supernova (exploding stars) and other extreme astrophysical environments. This includes synthesis of many atomic elements important for the formation of planets and for life itself (oxygen, silicon, calcium, iron..).The project will have a broad impact on graduate, undergraduate, and high school education, as well as the development of a technologically-literate work force as it will involve graduate and undergraduate students from the University of Michigan and the University of Notre Dame, together with faculty members and students from several other (primarily undergraduate) colleges and universities located in the Midwest, in close proximity to UM and UND. The ``hands on" training of these students in the use of advanced, state-of-the-art nuclear accelerators and nuclear-particle detectors together with the associated superconducting accelerator magnets thus will provide important training with applications in many possible career paths (e.g. those involving nuclear technology including nuclear medicine, or in teaching) . It also will keep faculty at these schools involved in fore-front physics research which can then be incorporated in their course work , public outreach functions , etc.