The State of Magnetic Axis Measurement of the Nica Collider Quadrupoles

As part of the NICA megascience project the magnetic-cryostat system of the superconducting Collider is being assembled. The structural units of the Collider are 88 dipole and 82 quadrupole magnets of various configuration. In order to improve the accuracy of alignment of quadrupole magnets to the theoretical closed orbit of the beam in the Collider, it is necessary to measure the position of the magnetic axis in the coordinate system of the magnet. Vibration wire technique is used to perform such measurements in VBLHEP. The system operates at ambient temperature and allows measuring the position of the magnetic axis with an accuracy of ±0.053 mm. The article presents the design of the magnetic measurement system, an accuracy assessment is made and the current results of measurements of the position of the magnetic axis of the NICA Collider quadrupole magnets.