论文标题
Ariadne源质量转子中磁场噪声的表征
Characterization of magnetic field noise in the ARIADNE source mass rotor
论文作者
论文摘要
Ariadne是一种基于核磁性的实验，它将在非极化源质量转子与附近的自旋偏振$^3 $ HE气体样本之间寻找新型轴突诱导的自旋依赖性相互作用。为了检测在亚第六型tesla级别的微弱轴轴信号，该实验依赖于低磁性背景和噪声。我们测量和表征来自原型钨旋翼的磁场背景。我们表明，我们目前的钨纯度和消灭过程水平满足了需求。我们进一步表明，噪声主要是由于几个离散偶极子引起的，这可能是由于制造过程中转子内部被困在转子内部的一些杂质所致。这是通过数值优化管道来完成的，该管道适合每个偶极子的位置和磁矩。我们发现，在当前的消极作用下，被困杂质的磁矩以$ 10^{ - 9} \ Mathrm {a} \ Mathrm {m}^2 $的限制。
ARIADNE is a nuclear-magnetic-resonance-based experiment that will search for novel axion-induced spin-dependent interactions between an unpolarized source mass rotor and a nearby sample of spin-polarized $^3$He gas. To detect feeble axion signals at the sub-atto-Tesla level, the experiment relies on low magnetic background and noise. We measure and characterize the magnetic field background from a prototype tungsten rotor. We show that the requirement is met with our current level of tungsten purity and demagnetization process. We further show that the noise is dominantly caused by a few discrete dipoles, likely due to a few impurities trapped inside the rotor during manufacturing. This is done via a numerical optimization pipeline which fits for the locations and magnetic moments of each dipole. We find that under the current demagnetization, the magnetic moment of trapped impurities is bounded at $10^{-9} \mathrm{A}\mathrm{m}^2$.
