磁场测量是检验磁铁质量的重要手段，它为磁铁生产提供质量监督和加速器运行提供重要参数。随着新加速器技术发展趋势，小孔径、长等效磁长度多极磁铁完整、精确的测量是亟需解决的技术难题之一。为解决该难题，本基金课题基于张力线技术研究一种完整的磁场测量方法。它以张力线为磁场探针，通过优化磁铁孔径中的张力线运动轨迹，并对它们切割磁力线时感应的电压信号进行分析，从而获得磁场完整、准确的信息。通过本课题的研究，不仅能够解决小孔径、长等效磁长度这种类型磁铁的精确测量难题，而且还可对磁铁极头区域磁场进行研究，这对磁铁好场区范围的界定有着重要参考价值(优化磁铁孔径大小)，将有利于磁铁技术的进一步发展。

Magnetic field measurement is an important method to test the quality of the magnet, which provides quality supervision for magnet production and important parameters for accelerator operation. With the development of new accelerator technology, the complete and accurate measurement of multipole magnet with small aperture and long equivalent magnetic length is one of the technical problems that need to be solved urgently. In order to solve this problem, a complete magnetic field measurement method based on the technique of stretched-wire will be studied. Stretched-wires will be used as the magnetic field measurement probe. By optimizing the trajectory of the wire in the aperture of magnet and analyzing the voltage induced from the stretched-wire, the complete and accurate information of the magnetic field can be obtained. Through the study of this subject, it not only can solve the measurement problem of multipole magnet with small aperture and long equivalent magnetic length, but also can study the magnetic field at the region of the magnetic pole, which is very important for the determination of the magnet good field region(optimize the magnet aperture), and that will be beneficial to the further development of the accelerator magnet technology.