New light physics beyond the Standard Model

超越标准模型的新光物理

• 批准号: 2889508
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2889508
• 关键词: New; light; physics; beyond; Standard

The project will involve studying the properties of possible new light particles beyond the Standard Model of particle physics and their astrophysical and cosmological signatures and constraints, with the aim to make predictions relevant to high energy theories, such as string theory, as well as upcoming experimental searches. The initial aim will be to reliably calculate the constraints on Kaluza Klein gravitons coming from the observation of a neutrino burst from supernoava 1987a, correcting previous calculations by taking into account plasma mixing effects (which might change the resulting limits on the coupling constants of such gravitons to visible sector matter by orders of magnitude). Such particles have been (controversially) predicted by string theory models as an inevitable consequence of the cosmological constant, and a strengthened constraint could rule out this scenario or open an avenue to a discovery. Plasma mixing effects have previously been considered for scalars (spin 0) and vectors (spin 1) but this would be the first ever computation for a spin 2 particle. The methodology will involve using techniques from finite temperature field theory to account for the in-medium effects on the production rate, and in particular the possibility of resonant production building on the previous work for the lower spin case. Depending on the results, it might also be interesting to investigate the impact of such finite temperature effects on the cosmological history of Kaluza Klein gravitons; since the Universe was extremely hot at early times such effects could again lead to dramatic changes compared to the previous prediction. This will enable a precise prediction of the Dark Matter relic abundance of such particles (which has previously been only estimated) and it might lead to predictions that can be feed into an experimental search programme. Subsequently, the scope will be widened to consider the constraints on other classes of new particles including axions, which are especially well motivated, as well as possible new light scalars that might play a role in sourcing Dark Energy. Again in this case, finite temperature and density effects have not been consistently accounted for. The overall impact of the project will be 1. On the immediate field of researchers in physics beyond the Standard Model and astroparticle physics. 2. On the field of string theory phenomenology, (part of which) has predicted such new light particles exist. 3. The experimental programme searching for new light particles in the UK and world-wide, by providing predictions and targets and complementary constraints.

该项目将涉及研究超出粒子物理标准模型的可能的新光粒子的特性及其天体物理和宇宙学特征和约束，目的是做出与高能理论（例如弦理论）以及即将进行的实验相关的预测。搜索。最初的目标是通过对 1987a 超新星中微子爆发的观测来可靠地计算对 Kaluza Klein 引力子的约束，通过考虑等离子体混合效应（这可能会改变此类引力子耦合常数的最终限制）来纠正之前的计算到可见部门物质的数量级）。弦理论模型（有争议地）预测，此类粒子是宇宙常数的必然结果，而强化的约束可以排除这种情况或开辟一条发现之路。等离子体混合效应之前已被考虑用于标量（自旋 0）和矢量（自旋 1），但这将是自旋 2 粒子的首次计算。该方法将涉及使用有限温度场理论的技术来解释介质对生产率的影响，特别是在较低自旋情况的先前工作的基础上建立共振生产的可能性。根据结果​​，研究这种有限温度效应对卡鲁扎克莱因引力子的宇宙学历史的影响也可能很有趣。由于宇宙在早期非常热，与之前的预测相比，这种效应可能会再次导致巨大的变化。这将能够精确预测此类粒子的暗物质遗迹丰度（之前仅进行了估计），并且可能将预测结果输入到实验搜索程序中。随后，范围将扩大，以考虑对其他类别的新粒子的限制，包括受到特别良好激励的轴子，以及可能在暗能量来源中发挥作用的可能的新光标量。同样，在这种情况下，有限的温度和密度效应并未得到一致的考虑。该项目的总体影响将是 1. 对标准模型和天体粒子物理学之外的物理学研究人员的直接影响。 2.在弦论现象学领域，（部分）已经预言了这种新的光粒子的存在。 3. 通过提供预测、目标和补充约束，在英国和世界各地寻找新的轻粒子的实验计划。