Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

Time-Domain Interpretation of PD Control01:07

Time-Domain Interpretation of PD Control

85
Proportional-Derivative (PD) control is a widely used control method in various engineering systems to enhance stability and performance. In a system with only proportional control, common issues include high maximum overshoot and oscillation, observed in both the error signal and its rate of change. This behavior can be divided into three distinct phases: initial overshoot, subsequent undershoot, and gradual stabilization.
Consider the example of control of motor torque. Initially, a positive...
85
Double Resonance Techniques: Overview01:12

Double Resonance Techniques: Overview

191
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
191
¹³C NMR: ¹H–¹³C Decoupling01:04

¹³C NMR: ¹H–¹³C Decoupling

1.0K
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
1.0K
Mean free path and Mean free time01:22

Mean free path and Mean free time

3.4K
Consider the gas molecules in a cylinder. They move in a random motion as they collide with each other and change speed and direction. The average of all the path lengths between collisions is known as the "mean free path."
3.4K
Fermi Level Dynamics01:12

Fermi Level Dynamics

228
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
228
Atomic Nuclei: Types of Nuclear Relaxation01:28

Atomic Nuclei: Types of Nuclear Relaxation

269
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers...
269

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

First Measurement of Time-Dependent CP Violation in the Flavor-Changing Neutral-Current Decay B^{0}→K_{S}^{0}μ^{+}μ^{-}.

Physical review letters·2026
Same author

Measurement of the Top-Quark Production Cross Section and Charge Asymmetry at LHCb.

Physical review letters·2026
Same author

Searches for B^{0}→K^{+}π^{-}τ^{+}τ^{-} and B_{s}^{0}→K^{+}K^{-}τ^{+}τ^{-} Decays.

Physical review letters·2026
Same author

First Evidence of the B_{s}^{0}→K^{-}π^{+}γ Decay.

Physical review letters·2026
Same author

Precision Measurement of CP Violation and Branching Fractions in B^{±}→K_{S}^{0}h^{±} (h=π, K) Decays and Search for the Rare Decay B_{c}^{±}→K_{S}^{0}K^{±}.

Physical review letters·2026
Same author

First Observation of the B[over ¯]_{s}^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Decay and Evidence for the B[over ¯]^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Decay.

Physical review letters·2026

相关实验视频

Updated: Jun 12, 2025

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
10:42

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh

Published on: May 3, 2019

6.7K

在D^{0}→π^{+}π^{-}π^{0}衰变中搜索时间依赖的CP违规.

R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3

  • 1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.

Physical review letters
|September 20, 2024
PubMed
概括

这项研究使用LHCb数据测量了D0衰变中的CP违规. 结果表明CP保存,在分析的D0→π+π-π0衰变中没有观察到显著的违规.

更多相关视频

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
11:33

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics

Published on: January 19, 2018

9.5K
Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting
08:40

Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting

Published on: February 14, 2019

8.2K

相关实验视频

Last Updated: Jun 12, 2025

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
10:42

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh

Published on: May 3, 2019

6.7K
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
11:33

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics

Published on: January 19, 2018

9.5K
Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting
08:40

Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting

Published on: February 14, 2019

8.2K

科学领域:

  • 粒子物理学 粒子物理学
  • 高能物理 高能物理
  • 量子色态动力学 量子色态动力学

背景情况:

  • CP 违规是粒子物理学中的一个关键现象,对于理解物质-反物质不对称性至关重要.
  • 由于其丰富的衰变模式,D0质子系统提供了一个独特的实验室来研究CP违规.

研究的目的:

  • 为了测量D0→π+π-π0衰变中的时间依赖的CP违规.
  • 为了测试标准模型对 CP 对称性的预测,在魅力领域.
  • 为了限制超越标准模型的新物理场景.

主要方法:

  • 利用了来自LHCb实验 (2012,2015-2018) 的大量质子-质子碰撞数据集.
  • 通过D*(2010)+→D0π+衰变确定了D0候选物的初始风味.
  • 使用D0→K-π+π0作为控制道来验证测量技术.

主要成果:

  • 测量了依赖时间的CP不对称度的梯度, ΔY,在D0→π+π-π0衰变中.
  • 得到的 ΔY = (-1.3 ± 6.3 ± 2.4) × 10^{-4}.
  • 该结果在统计学上与CP保存假设相兼容.

结论:

  • 该测量为D0→π+π-π0衰变中的CP保存提供了有力的证据.
  • 这一发现有助于精确测试在魅力领域的标准模型.
  • 增加亮度的进一步研究可能会提高对CP违规行为的敏感性.