相关实验视频

Updated: Jul 16, 2025

Setting Limits on Supersymmetry Using Simplified Models

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

来自SERF共磁计的axion-like暗物质的限制

Itay M Bloch^1,2, Roy Shaham^3,4, Yonit Hochberg⁵

¹Berkeley Center for Theoretical Physics, University of California, Berkeley, CA, 94720, USA.

Nature communications

|September 18, 2023

概括

纳斯达克协作为超轻的轴子类粒子,潜在的暗物质候选物,设定了新的地球界限. 这些发现显著改善了对质子和中子合的先前约束.

科学领域:

粒子物理学和宇宙学
暗物质检测暗物质检测

背景情况:

超轻的轴子样粒子是宇宙学暗物质的理论候选者.
这些粒子可以产生依赖时间的磁场,提供潜在的检测特征.
关于轴子类粒子合的现有天体物理界限是强大的,但可以通过地面搜索来补充.

研究的目的:

为了建立像轴子这样的粒子与中子和质子的合的地球边界.
使用新型探测器在特定质量范围内探索axion类暗物质的参数空间.
为了超越这些合的现有天体物理和地球限制.

主要方法:

使用了高贵和的自旋探测器,用于超轻连贯暗物质 (NASDUCK) 协作的探测器.
在高灵敏度的Spin-Exchange Relaxation-Free (SERF) 系统中使用了贵重气体和金属原子核.
进行了为期一个月的实验搜索,目标是像axion这样的暗物质场.

主要成果:

在质量范围为1.4×10−12 eV/c2到2×10−10 eV/c2的质子和中子的轴子状粒子合中,建立了新的地球界限.
实现了超越天体物理界限的极限,并将以前的地球限制提高了高达两倍的数量.
提供了第一个可靠的地球边界,对质子合到类似轴子的暗物质,探测以前未被探索的参数空间.

结论:

纳斯达克 (NASDUCK) 实验成功地制约了超轻的轴子类粒子合,大大推进了陆地暗物质的搜索.
这些结果突出了SERF磁力计在敏感检测axion类暗物质方面的潜力.
这项研究为探索与标准模型粒子的axion-like暗物质相互作用开辟了新的途径.

更多相关视频

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Published on: July 20, 2022

High-Speed Magnetic Tweezers for Nanomechanical Measurements on Force-Sensitive Elements

High-Speed Magnetic Tweezers for Nanomechanical Measurements on Force-Sensitive Elements

Published on: May 12, 2023

相关概念视频

Potential Due to a Magnetized Object

Potential Due to a Magnetized Object

Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...

Magnetostatic Boundary Conditions

Magnetostatic Boundary Conditions

An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...

Diamagnetism

Diamagnetism

Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....

Magnetic Moment of an Electron

Magnetic Moment of an Electron

Electrons revolving around a nucleus are analogous to a circular current carrying loop. This current produces a magnetic dipole moment proportional to the electron's orbital angular momentum. Since the orbital angular momentum is quantized in terms of the reduced Planck's constant, the dipole moment is quantized in the Bohr Magneton. The value of the Bohr magneton is 9.27 x 10-24 Am2. Electrons also have an intrinsic spin angular momentum, and the associated spin magnetic moment is...

Magnetic Damping

Magnetic Damping

Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...

Magnetic Vector Potential

Magnetic Vector Potential

In electrostatics, the electric field can be written as the negative gradient of the potential. In magnetostatics, the zero divergence of the magnetic field ensures that the magnetic field can be expressed as the curl of a vector potential. This potential is known as the magnetic vector potential.
Consider an ideal solenoid with n turns per unit length and radius R. If I is the current through the solenoid, the magnetic field inside the solenoid is expressed as the product of vacuum...