Nuclear Physics Consolidated Grant (Equipment)

核物理综合补助金（设备）

• 批准号: ST/L005735/1
• 负责人: Robert Wadsworth
• 金额: $ 2.65万
• 依托单位: University of York
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FL005735%2F1
• 关键词: Nuclear; Physics; Consolidated; Grant; Equipment

The atomic nucleus, which forms the tiny massive core at the centre of the atom, is composed of protons and neutrons and each of these particles are themselves comprised of quarks. However, this knowledge does not allow us to make a complete prediction of the behaviour of any given nucleus or isotope. The system is too complex, involving three of the four fundamental forces: the electromagnetic, weak and strong nuclear forces. The behaviour of the nucleus is often described as an emergent phenomenon as it cannot be readily predicted from its component parts. This drives theoretical effort and the need to benchmark theory with precision measurements. Our research is aimed at studying the funadamental properties of atomic nuclei, the origin of elements in the cosmos and applications of nuclear technology. We study nuclei on the very limits of stability, in particular those with an excess of protons, and those which have the same number of protons and neutrons (N=Z nuclei). The N=Z nuclei exhibit special symmetries and deviations from these symmetries tell us very detailed information on the validity of competing nuclear models. Such measurements are very challenging as these nuclei are very difficult to produce in any quantity to perform experiments on. Our programme uses some of the principal facilities for nuclear physics worldwide where such exotic nuclei can be produced. Our work involves studies of how protons and neutrons interact in N=Z nuclei and to what extent the clustering of nucleons (eg into alpha particles) occurs in such nuclei. In our work we aim to addess specific questions related to nuclei residing in three of these regions, (i) N=Z nuclei around mass 70, (ii) deformed nuclei around mass 150 and (iii) nuclei around the neutron deficient lead region, where one of the best examples of nuclear shape co-existence has been observed to date at very low excitation energy. A further aspect of our research into the structure of nuclei concerns their shape. It is a remarkable property of the nucleus that it can adopt different shapes: spherical, oblate (smartie-shaped) and prolate (rugby-ball shaped) often for a small costs in energy. Predicting the shape of a nucleus and how this shape evolves as the nucleus is excited (given more energy) is extremely challenging from a theoretical perspective. Determining nuclear shape experimentally can help to discriminate between competing models of the nucleus and pin down our theoretical understanding. Nuclear structure effects relating to nuclear shapes and the phenomenon of shape co-existence are found in many regions of the chart of the nuclides. A third strand of our research is into the origin of the chemical elements in stars, and the role played by nuclear physics in this question. Some elements and isotopes are only produced in very hot and exotic events such as exploding stars: novae and supernovae. In these events, a rapid series of nuclear reactions takes place. We seek to understand how rapidly such reactions take place by reproducing them in the laboratory. This is very challenging as many of the nuclei involved in these studies are themselves radioactive and difficult to produce. Nevertheless, we are able to advance our understanding of how the chemical elements are created. The final area of research is into the mechanisms of nuclear fission, with emphasis on exploring how these develop in nuclei that reside away from the well known transactinide region of nuclei which can undergo induced fisson or in the case of the heaviest nuclei even spontaneous fission following their creation. Our data on these new regions of fission, such as in the light mercury isotopes around mass 180, are presenting challenges to the present models of the nuclear fission process. Our proposed work in this area will provide new data on extremely exotic nuclei to help develop the models of the fission process further.

原子核在原子中心形成微小的质量核心，由质子和中子组成，而这些粒子中的每一个本身都由夸克组成。然而，这些知识并不允许我们对任何给定的原子核或同位素的行为做出完全的预测。这个系统太复杂了，涉及四种基本力中的三种：电磁力、弱核力和强核力。原子核的行为通常被描述为一种涌现现象，因为它不能从其组成部分中轻易预测。这推动了理论工作和需要用精确的测量来基准理论。 我们的研究旨在研究原子核的基本性质，宇宙中元素的起源以及核技术的应用。我们研究原子核的稳定极限，特别是那些质子过剩的原子核，以及那些质子数和中子数相同的原子核（N=Z原子核）。N=Z原子核具有特殊的对称性，偏离这些对称性告诉我们关于竞争核模型有效性的非常详细的信息。这种测量是非常具有挑战性的，因为这些核很难产生任何数量的进行实验。我们的计划使用一些主要的核物理设施，在世界各地的这种奇异的核可以生产。我们的工作包括研究质子和中子如何在N=Z核中相互作用，以及在这种核中核子的聚集（例如成α粒子）达到什么程度。在我们的工作中，我们的目标是addess具体的问题有关的核居住在三个这些地区，（i）N=Z核周围的质量70，（ii）变形核周围的质量150和（iii）核周围的中子缺乏铅区域，其中一个最好的例子，核形状共存已被观察到在非常低的激发能。我们研究原子核结构的另一个方面是关于它们的形状。原子核的一个显著特性是，它可以采用不同的形状：球形，扁球形（smartie形）和长球形（橄榄球形），通常需要很小的能量成本。从理论的角度来看，预测原子核的形状以及这种形状如何随着原子核被激发（给予更多能量）而演变是非常具有挑战性的。通过实验确定核的形状有助于区分核的竞争模型，并确定我们的理论理解。在核素图的许多区域中发现了与核形状有关的核结构效应和形状共存现象。 我们研究的第三个方面是恒星中化学元素的起源，以及核物理在这个问题中所起的作用。一些元素和同位素只在非常热和奇异的事件中产生，例如爆炸的恒星：新星和超新星。在这些事件中，会发生一系列快速的核反应。我们试图通过在实验室中重现这些反应来了解这些反应发生的速度。这是非常具有挑战性的，因为这些研究中涉及的许多核本身具有放射性，难以生产。尽管如此，我们能够推进我们对化学元素是如何产生的理解。研究的最后一个领域是进入核裂变的机制，重点是探索这些如何在远离核的已知transactinide区域的核中发展，这些区域可以进行诱导裂变，或者在最重的核的情况下，甚至在它们创建后自发裂变。我们对这些新的裂变区域的数据，例如在质量180左右的轻汞同位素中，对目前的核裂变过程模型提出了挑战。我们在这一领域的工作将提供有关极端奇异核的新数据，以帮助进一步发展裂变过程的模型。

项目成果

Quadrupole collectivity in Ca 42 from low-energy Coulomb excitation with AGATA

• DOI: 10.1103/physrevc.97.024326
• 发表时间: 2018-02
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: K. Hadyńska-Klęk;P. Napiorkowski;M. Zielińska;J. Srebrny;A. Maj;F. Azaiez;J. Dóbon;M. Kicińska-Habior;F. Nowacki;H. Naïdja;B. Bounthong;T. R. Rodríguez;G. Angelis;T. Abraham;G. A. Kumar;D. Bazzacco;M. Bellato;D. Bortolato;P. Bednarczyk;G. Benzoni;L. Berti;B. Birkenbach;B. Bruyneel;S. Brambilla;F. Camera;J. Chavas;B. Cederwall;L. Charles;M. Ciemala;P. Cocconi;P. Coleman-Smith;A. Colombo;A. Corsi;F. Crespi;D. Cullen;A. Czermak;P. Désesquelles;D. Doherty;B. Dulny;J. Eberth;E. Farnea;B. Fornal;S. Franchoo;A. Gadea;A. Giaz;A. Gottardo;X. Grave;J. Grebosz;A. Görgen;M. Gulmini;T. Habermann;H. Hess;R. Isocrate;J. Iwanicki;G. Jaworski;D. Judson;A. Jungclaus;N. Karkour;M. Kmiecik;D. Karpinski;M. Kisieliński;N. Kondratyev;A. Korichi;M. Komorowska;M. Kowalczyk;W. Korten;M. Krzysiek;G. Lehaut;S. Leoni;J. Ljungvall;A. Lopez-Martens;S. Lunardi;G. Maron;K. Mazurek;R. Menegazzo;D. Mengoni;E. Merchán;W. Mȩczyński;C. Michelagnoli;B. Million;S. Myalski;D. Napoli;M. Niikura;A. Obertelli;S. Ozmen;M. Palacz;L. Prochniak;A. Pullia;B. Quintana;G. Rampazzo;F. Recchia;N. Redon;P. Reiter;D. Rosso;K. Rusek;E. Sahin;M. Salsac;P. Söderström;I. Stefan;O. Stézowski;J. Styczeń;C. Theisen;N. Toniolo;C. Ur;R. Wadsworth;B. Wasilewska;A. Wiens;J. Wood;K. Wrzosek-Lipska;M. Ziȩbliński

Test of digital neutron-gamma discrimination with four different photomultiplier tubes for the NEutron Detector Array (NEDA)

使用用于中子探测器阵列 (NEDA) 的四种不同光电倍增管进行数字中子伽马辨别测试

• DOI: 10.1016/j.nima.2014.08.023
• 发表时间: 2014-12-11
• 期刊: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
• 影响因子: 1.4
• 作者: Luo, X. L.;Modamio, V.;Wadsworth, R.
• 通讯作者: Wadsworth, R.

Testing microscopically derived descriptions of nuclear collectivity: Coulomb excitation of 22Mg

• DOI: 10.1016/j.physletb.2018.05.064
• 发表时间: 2017-09
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: J. Henderson;G. Hackman;P. Ruotsalainen;Steven Ragnar Stroberg;K. Launey;F. A. Ali;N. Bernier

Conceptual design of the early implementation of the NEutron Detector Array (NEDA) with AGATA

• DOI: 10.1140/epja/i2016-16055-8
• 发表时间: 2016-03
• 期刊: The European Physical Journal A
• 作者: T. Hüyük;A. Di Nitto;G. Jaworski;A. Gadea;José Javier Valiente-Dobón;J. Nyberg;M. Palacz;P. Söderström;Ramon Jose Aliaga-Varea;G. de Angelis;A. Ataç;J. Collado;C. Domingo-Pardo;F. J. Egea;N. Erduran;S. Ertürk;G. de France;R. Gadea;V. González;V. Herrero-Bosch;A. Kaşkaş;V. Modamio;M. Moszynski;E. Sanchis;A. Triossi;R. Wadsworth

Digital pulse-timing technique for the neutron detector array NEDA

• DOI: 10.1016/j.nima.2014.12.002
• 发表时间: 2015-11
• 期刊: Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
• 影响因子: 1.4
• 作者: V. Modamio;J. Valiente-Dobon;G. Jaworski;T. Hüyük;A. Triossi;J. Egea;A. Nitto;P. Söderström