相关实验视频
Updated: Jul 25, 2025

07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
8.6K
在MicroBooNE探测器中,第一次测量了子反中微子相互作用中的准弹性子产生
P Abratenko1, D Andrade Aldana2, J Anthony3
1Tufts University, Medford, Massachusetts 02155, USA.
Physical review letters
|June 24, 2023
概括
这项研究报告了使用MicroBooNE数据首次测量卡比博抑制的Lambda (Λ) baryons生产截面. 测量的截面为中微子相互作用模型提供了关键数据.
科学领域:
- 粒子物理学 粒子物理学
- 中微子物理学 中微子物理学
- 子光谱学 子光谱学
背景情况:
- 中微子相互作用对于理解核物理学至关重要.
- 卡比博抑制的过程为粒子相互作用提供了独特的见解.
- 精确的截面测量对于完善中微子相互作用模型至关重要.
研究的目的:
- 介绍Cabibbo抑制的Lambda (Λ) baryons生产截面的第一个测量.
- 为了利用MicroBooNE探测器暴露在费米实验室主注入器中微子束中的数据.
- 将实验结果与来自GENIE事件发生器的理论预测进行比较.
主要方法:
- 使用MicroBooNE探测器收集的数据,目标上有2.2×10^20个质子 (中微子模式) 和目标上有4.9×10^20个质子 (反中微子模式).
- 合并自动事件选择与手动扫描候选的L生产事件.
- 分析仅限于在MicroBooNE检测值以上衰变的L baryons.
主要成果:
- 观察到的候选事件与自动选择中的GENIE预测一致.
- 手部扫描发现了3-5个事件,而蒙特卡洛盲目的预测是3.7±1.0个事件.
- 测量了 2.0_{-1.7}^{+2.2}×10^{-40} cm2/Ar 的流量平均截面,用于 Cabibbo 抑制的 Λ 生产.
结论:
- 这项工作提供了Cabibbo抑制的L-baryon生产的第一个实验约束.
- 结果为提高中微子相互作用模拟的准确性提供了有价值的数据.
- 进一步的研究可以完善这些测量,并探索相关的罕见过程.
更多相关视频
相关概念视频
Nuclear Binding Energy
12.5K
The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect indicates a “loss” in mass of 4.0331 amu – 4.0026 amu = 0.0305 amu. The loss in mass accompanying the formation of an atom from protons, neutrons, and electrons is due to the conversion of that mass into energy that is evolved as the atom forms. The nuclear binding energy is the energy produced when the atoms’ nucleons...
12.5K
Thomson's e/m Experiment
3.9K
In a beam of charged particles created by a heated cathode, the particles move at different speeds. However, many applications need a beam with uniform particle speeds. An arrangement known as a velocity selector uses electric and magnetic fields to pick particles with a particular speed from the beam.
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The...
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The...
3.9K
Nuclear Overhauser Enhancement (NOE)
756
Irradiation of a spin-active nucleus causes an increase or decrease in the signal intensity of neighboring nuclei that are not necessarily chemically bonded or involved in J-coupling. This phenomenon, called the Nuclear Overhauser Enhancement (NOE), results from through-space interactions between the nuclear spins. The NOE effect decreases with increasing internuclear distance and is generally not observed beyond 4 angstroms. In NOE, dipole-dipole interactions between neighboring...
756
Atomic Nuclei: Nuclear Spin State Population Distribution
1.0K
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
1.0K
Atomic Nuclei: Nuclear Magnetic Moment
1.2K
All atomic nuclei are positively charged. When they have a nonzero spin, they behave like rotating charges. As a consequence of their charge and spin, these nuclei generate a magnetic field (B). This, in turn, gives rise to a magnetic moment (μ), which is randomly oriented in the absence of an external magnetic field. When an external magnetic field (B0) is applied, the magnetic moment vectors can align with the field or against it in 2 + 1 orientations. A hydrogen nucleus, which is just a...
1.2K
Types of Radioactivity
16.9K
The most common types of radioactivity are α decay, β decay, γ decay, neutron emission, and electron capture.
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
16.9K

