DarkLight at TRIUMF/ARIEL -- A Search for New Physics in e+e- Final States with an Invariant Mass between 10-20 MeV.

TRIUMF/ARIEL 的 DarkLight——寻找具有 10-20 MeV 之间不变质量的 e- 最终状态的新物理。

• 批准号: SAPPJ-2022-00032
• 负责人: Hasinoff, Michael
• 金额: $ 10.93万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Project
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762994
• 关键词: DarkLight; TRIUMF; ARIEL; Search; New

There are still many unanswered questions today in particle physics and cosmology. Although we now have a highly successful Standard Model (SM) of particle physics that links 3 of the 4 known forces it is very clear that the SM is incomplete. It does not contain any Dark Matter (DM) particles and it cannot explain Dark Energy (DE) which is the largest component of the energy budget and is responsible for the accelerating expansion of the universe. Moreover, our visible universe makes up only about 5% of the total mass of the universe while DM contributes about 23%. The search for an understanding of the elusive DM is one of the greatest scientific quests of our age. In our current understanding, the known, uncharged particles, the three neutrinos, cannot be a major component of the inferred dark matter mass, and so we posit at least one as-yet unobserved new particle. Recently, there has been a focus on a mediator of a new fifth force with mass e- Ta A' --> e- Ta (e+e-). The use of the ARIEL e-linac has the benefit of allowing a relatively low beam energy, thus reducing the boost of the produced boson and opening up the small angles of these forward-going decay leptons. We propose a two spectrometer setup optimized for the anomaly region and a thin foil target to achieve sufficient luminosity. The magnets will be designed and constructed by the MIT group. Each spectrometer will be instrumented with a focal plane detector consisting of 3 GEM detector planes, read out via standard APV electronics. They will be provided by the Hampton University group. The GEMs will be followed by a layer of scintillating paddles as the fast trigger detectors. A consortium of Canadian institutions (UBC, Manitoba, Saint Mary's, TRIUMF, & Winnipeg) will design & construct the scintillators. They will also provide the readout electronics for the trigger system and handle the integration with the ARIEL accelerator. Stony Brook University will take care of the data acquisition and slow control system. In a 2nd stage experiment TRIUMF would install a beamline chicane to allow re-circulation of the electron beam through the accelerating cavity to increase the beam energy to 50 MeV and extend the reach of the experiment. If our CFI proposal is successful TRIUMF would also install a 2nd cryomodule to increase the beam energy up to 75 MeV in single user mode and allow simultaneous operation of DL and ARIEL at 50 MeV to significantly increase the reach of our experiment.

在粒子物理学和宇宙学中，今天仍然有许多悬而未决的问题。尽管我们现在有了一个非常成功的粒子物理标准模型(SM)，它连接了4个已知力中的3个，但很明显，SM是不完整的。它不包含任何暗物质(DM)粒子，也无法解释暗能量(DE)，暗能量是能量收支的最大组成部分，是宇宙加速膨胀的罪魁祸首。此外，我们可见的宇宙只占宇宙总质量的5%左右，而DM贡献了大约23%。寻求对难以捉摸的DM的理解是我们这个时代最伟大的科学任务之一。在我们目前的理解中，已知的未带电粒子，即三个中微子，不可能是推断的暗物质质量的主要组成部分，因此我们假设至少有一个尚未观测到的新粒子。最近，人们关注的焦点是质量为e-Ta A‘--&gt；e-Ta(e+e-)的新的第五种力量的介体。使用Ariel电子直线加速器的好处是允许相对较低的束流能量，从而减少产生的玻色子的助推，并打开这些向前衰减的轻子的小角度。我们提出了一种针对异常区和薄箔目标进行优化的双光谱仪设置，以获得足够的光度。磁铁将由麻省理工学院的团队设计和建造。每个光谱仪将配备一个由3个宝石探测器平面组成的焦平面探测器，通过标准的APV电子器件读出。它们将由汉普顿大学集团提供。宝石后面会有一层闪烁的球拍，作为快速触发探测器。一个由加拿大机构组成的财团(UBC、马尼托巴省、圣玛丽、TRIUMF和温尼伯)将设计和建造闪烁体。他们还将为触发系统提供读出电子设备，并处理与Ariel加速器的集成。石溪大学将负责数据采集和慢速控制系统。在第二阶段的实验中，TRIUMF将安装一个光束线发光器，以允许电子束通过加速腔再循环，从而将束流能量增加到50 MeV，并扩大实验的范围。如果我们的CFI提议成功，TRIUMF还将安装第二个低温模块，在单用户模式下将束流能量增加到75 MeV，并允许DL和Ariel在50 MeV同时运行，以显着增加我们实验的覆盖范围。