A direct measurement of the 17O(a,g) 21Ne cross section

核天体物理学是核物理学的众多应用之一，也可以说是最令人兴奋的应用之一。它试图解释我们周围的所有元素，空气中的氧气，血液中的铁，电脑芯片中的硅，都是从哪里来的。它们是在哪里以及如何形成的？除此之外，核天体物理学试图了解核反应如何影响所有恒星的生与死。如此微小的物体是如何影响像恒星这样巨大的物体的呢？大多数恒星通过长时间燃烧稳定的元素（如我们熟悉的碳和氧）获得能量。能量是由核反应产生的，将一种元素转化为另一种元素。然而，并非所有类型的碳都是相同的。不同的类型有不同数量的中子（但相同数量的质子），被称为同位素。天文学家可以通过观察恒星发出的光来研究它们。从这种光中，他们可以知道产生了什么元素，这给了核物理学家关于哪些核反应可能是重要的信息。我们知道，许多比铁重的元素都是通过所谓的s-过程，在现有的同位素中加入中子而产生的。拟议的研究方案将利用温哥华的TRIUMF实验室现有的束流来研究一种反应，这种反应会影响s过程中有多少中子，从而影响星星中产生的重元素的丰度。

Nuclear astrophysics is one of the many applications of nuclear physics and arguably one of the most exciting. It tries to explain where all the elements around us, the oxygen in the air, the iron in our blood, the silicon in computer chips, come from. Where and how were they formed? On top of this, nuclear astrophysics tries to understand how nuclear reactions affect the life and death of all stars. How do such tiny things influence such massive objects as stars? Most stars get their energy by burning stable elements, such as the carbon and oxygen we are familiar with, over long periods of time. The energy is produced by nuclear reactions, turning one element into another. However, not all types of carbon, for example, are the same. Different types have different numbers of neutrons (but the same number of protons) and are called isotopes. Astronomers can study stars by looking at the light that shines from them. From this light they can tell what elements are produced and this gives nuclear physicists information on which nuclear reactions could be important. We know that many of the elements heavier than iron are produced by the so-called s-process by adding neutrons to existing isotopes. The proposed research programme will use the beams available at the TRIUMF laboratory in Vancouver to study one reaction which influences how many neutrons are available for the s-process and therefore what the abundances of the heavy elements produced in the star are.